Inplant Training Report (autosaved).docx

CANE MANAGEMENT SYSTEM ZONE WISE CANE SUPPLY FOR 2016-17 SEASON Zone RAMPUR

Division RAMPUR NAINEGALI BAGALKOT

RAMPUR Total HOOVANUR

HOOVANUR Total NIDAGUNDI

HOOVANUR HUNGUND KAMATAGI NIDAGUNDI EAST NIDAGUNDI WEST YALAGUR MUDDEBIHAL

NIDAGUNDI Total Zone Total Non-Zone Total Grand Total

Net Weight (MT) 35537.342 61973.238 51035.381 148545.961 17823.734 20664.143 27228.445 65716.322 52871.859 32881.678 38457.532 28367.791 152578.86 366841.143 80850.244 447691.387

TRANSPORTATION OF CANE Mode of transportation of cane Cane centres are situated at a distance 10-50 kms from the factory. Canes are transported to the factory through trucks and trolleys. The cane centres are always in contact with the factory by the help of cane field supervisors. Net Weight(lakh Sl.No Carrier Type % Tons) 1

C-Bullock Cart

24681.736

5.51

2

E-Tractor Drown Cart

22517.407

5.03

3

L-Lorry

79662.568

17.79

4

R-Double Tractor

319925.411

71.46

5

T-Single Tractor

904.265

0.20

447691.387

100.00

Grand Total

5|PAGE

METHOD OF IDENTIFYING The factory producers, the entire cane from crushing throughout the crop season. All the cane growers have to get the cane supply tickets to sell their cane to their factory. Sugarcane variety selection and development Varieties play a major role not only increasing cane productivity but also sugar recovery. In Karnataka, judicious varietal balance of improved high sugar early and mid-late maturing varieties have played an important role in increase in sugar recovery. The main target of organisational set up to persuade the farmers for adoption of the improved cultivation practice and educate them about high yielding varieties. Main functions are summarised as below:  Introduction of new varieties with the help of premium paid by factory.  By providing incentives in the form of free seed, free agro chemicals to propagate new varieties.The ultimate objective of any effective sugar cane breeding and selection programme is the development of new varieties capable of producing sugar at a low-cost thancould be attainable with existing varieties. Selected varieties in Karnataka Region

CO 86032

PI 00 1110

CO 92005

PI 00 1401

CO 94012

PI 11639

COC 671

PI 2218

SNK 632

CO 91010

SNK K7680

COM 0265

6|PAGE

CANE UNLOADER Double glider cane unloader cane unloaders with sling bar attachments mounted on two gantries that unload the cane on to the two feeder tables on either side of the main carrier.The feeder table has 7 Mts. width x 7 Mts. length with 8 studs of 150 mm pitch chain driven by 20 HP Sq. cage motor coupled with VFD & Gearbox regulated speed from 0 to 3 m/min.With breaking strength 40000 Kgs & final speed 3-10mts/min.

MAKE

UNLOADE UNLOADE UNLOADE R NO1 R MO 2 R NO 3 Kolar Engg. Kolar Engg. Structural Engg. 7.5 7.5 12.5

CAPACITY(M. T) HEIGHT OF 20 LIFT(M) POWER(HP) 40

UNLOADE R NO 4 Extract Engg. 12.5

20

10

10

40

40

40

CANE CARRIER The cane carrier is of apron type with steel carrier slats of Walchandnagar India Ltd make. It has a width of 2000 mm and depth 1500 mm. Horizontal loading length 30Mts. 3 Nos. of stands, 200mm pitch and slope of 16° (8.5+14.5)=23 Mts. Inclined Length, 80,000 Kgs Breaking Strength. Cane carrier driven by 75 HP motor, 1480 RPM. Motor directly coupled to electric dynamic, variable speed gear.

7|PAGE

CANE PREPARATION The process of reducing the cane fed to the mill into small pieces suitable for the subsequent extraction process is referred to as cane preparation. The efficiency and throughput of the extraction plant depend significantly on the preparation of the cane presented to it. The cane preparation equipment can use more than 25 % of total factory power requirements. The type of drive employed and the efficiency with which the power is utilized are therefore very important. Objective  To reduce the size of the pieces of cane to a size suitable for handling in the extraction process.  To rupture as many of the sugar bearing cells in the cane as possible to facilitate the extraction of sugar.  To produce a material that has the right characteristics for milling and diffusion.

Preparatory Devices  Cutter  Leveller  Fibrizor CUTTER: Cane chopper having 48 knives driven by 250 HP motor make by Kirloskar, IB – 621 frame, 735 RPM TEFC slipring electric motor having clearance of 950 mm and swing dia. 1600 mm .It has H1/315 type gear box ratio 20.76/1. Cutter uses double edge knives which has a tip speed of 22.37 m/s.The motion of the cutter is in the opposite direction to that of the carrier.

8|PAGE

LEVELLER: 60 blades driven by continuously rated slipring double motors each 250 HP and directly coupled to fly wheel type coupling – 585 RPM synchronous speed. It has a Clearance of 285 mm and swing dia of 1600 mm. Leveller uses double edge knives which has a tip speed of 49 m/s.The motion of the cutter is in the same direction to that of the carrier. FIBRIZER: It is of Uttam Industries Makeand has 152 Heavy duty swing hammer with 90 sq. mm tip, with swing dia of 2200 mm.Each hammer weighing 21 Kg. Fibrizor driven by 2 ,1000 Kw motors of 745 RPM made by Sumo. The fibrizor has a v-tip roller over which the bagasse enters the fibrizer and the distance between the roller and the tip is 220mm,while that between the rtip and the bottom is 25 mm,the distance between the tip and the squared cavity anvil plate is 80 mm.Fibrizer is the main cane prepation device while the cutter and leveller just prepare it for reducing the load on the motor of the fibrizer. Elevating Rake Carrier:- made by Uttam Industries which has a Size of 2.08mtr

x 17.63mtr, Breaking load 80 Ton & linear speed of carrier 27.61 mtr./min. It is driven by a VFD Drive 75.0 Hp motor with 1440 RPM.It has a planetry gear box with helical gears with rating of 16200kg.m. The elevating rake carrier drops the fibrised cane onto a belt conveyor.

9|PAGE

Belt conveyor

Belt conveyor Type : Nylon Grade : M-24

Motor Make : Alstom Power: 40 HP

Rating :800/5 Width : 2000mm Length: 15 Mts.

Speed : 1440 RPM Stator : VFD

Gear Box Make : Elecon Type : PC-16R11V-12.20 Ratio : 20:1

Magnetic Separator: One magnetic separator from Magnetic Corporation of

India make, CMB-2008/022 type, 18 – Kg. weight lifted 300mm height. Preperatory index

88.8 88.6 88.4 88.2 88 87.8 87.6 87.4 87.2

88.56

88.65

88.62

87.76

2013-14

2014-15

2015-16

2016-17

10 | P A G E

MILL The function of Mill is extraction of juice from cane by the effect of pressure. Milling has number of units  Roller.  Trash plate.  Housing.  Grooving.  Speed reduction system  Torque transmission system  Moisture reduction system  Mill hydraulic system  Scrapper.  Forced lubrication system  Inter rack carriers  Mill setting.  Imbibition.  Feed arrangement(Donnelly chute).

HOUSING The side frames of mills are generally called as either Housing or Mill Cheeks. Types of housing:  Standard housing.  Squire housing.  Standard inclined (coil) housing.  Fives housing. The purpose of the mill housing is to maintain the working elements particularly the rolls in their desired orientation. This orientation needs to be flexible to allow for different roll sizes and settings. The basic mill comprises three rolls: the top which needs to be able to "float" upwards during eration and the feed and discharge roils that need to be adjustable sideways. Some feed and discharge bearings can be packed up to adjust their vertical position.

11 | P A G E

ROLLER GROOVING: The capacity of mill with smooth rollers is much less than that of a mill of the same dimensions and the same speed, but with grooved rollers. Further, the grooved rollers break up the bagasse more completely. Grooves have following main significance in milling:  It provides grips in feeding.  It increases mill capacity.  It provides drain to extract juice. The main disadvantages of mill roll grooving are: • The roots of the grooves constitute "stress raisers" that can lead to fatigue failure of the shell and shaft. • For the same work opening between two rolls the free gap to pass any extraneous solid objects such as tramp iron or rocks is reduced,increasing the likelihood of roll damage. Common dimensions of roll grooves are: • Pitch: From 25mm (1") to 15 mm (3"), with 50 mm (2") probably the most widely used. • Groove included angle: From 40° to 55°. 12 | P A G E

Circumferential grooves: The universal type of grooving is formed by grooving the roller with notches describing complete circles in planes perpendicular to its axis.

Messchaert grooves: The grooving mainly adopted on feed rollers is also known by Messchaerts or Juice grooves. The only objective of such grooving is improvement of extraction. Special scrappers or combs are fitted so that the grooves are kept free of the bagasse.

13 | P A G E

Chevron grooves: Such kind of grooving is adopted for basically griping on bagasse so that we can achieve improvement in feeding of bagasse. Chevron is placed only on two feeding rollers i.e. on top roller and on feed roller.

DONNELLY CHUTE: In the gravity feed system closed feed chute is provided at an angle of 75ᵒ to 90ᵒ to the horizontal. The inner part of this chute, the side plates have to be very smooth and are preferably of stainless steel to avoid frictional resistance and for easy flow of bagasse or prepared cane.

14 | P A G E

UNDERFEED ROLLER: The most commonly used feeding device are made of cast iron and grooved, with diameter half to two thirds of the mill roller diameter. The clearance between the underfeed roller and the mill feed roller has to be minimum preferably 7 – 10 mm. TRASH PLATE AND SCRAPPER The trash plate and scraper both are used to scrap the bagasse from the rollers. It helps for the greater extraction of juice from the bagasse and also reduces re-absorption. Trash Plate:

Trash plate is a device, which assists the flow of bagasse from feed to discharge roller with minimum possible friction and minimum power

required. So profile of trash plate and position of trash plate is very much important for smooth operation. The trash plate has grooves similar to that of roller.

TORQUE TRANSMISSION SYSTEM The mill rollers are driven by either D.C. or A.C. motor the power is transmitted through the set of gear reduction system and finally the torque to rotate the rollers are transmitted by various methods.  Tail bar coupling  Rope coupling  Cardigan shaft  Hydraulic drives

15 | P A G E

ROLLER Mill rolls are usually constructed of a shaft of steel, onto which is shrunk a cast iron shell.

HYDRAULIC SYSTEM Mill hydraulic system is to regulate the cane crushing in the mills, the top roller is connected to the hydraulic system,

16 | P A G E

during higher cane flow the top roller will move up, to prevent the over lifting of roller the counter weight is given by hydraulic operated RAM. The load is maintained 150 to 250 kg/cm2. Speed reduction system: Usually the mill rollers are driven by a Motors or Turbine the rated speed of the mill roller is 2- 7 rpm. To attain the specified speed gear reduction system is used. The gear reduction by  Spur or helical gear multi step reduction  Planetary gear box system

FORCED LUBRICATION SYSTEM FLS is provided to cool the oil which is circulated to the speed reduction gearbox at the required pressure. Oil is cooled by the water cooled heater. Capacity The crushing capacity of milling plant is quantity of cane crushed per hour. This capacity depends upon following factors: Mill size  R.P.M of mill  Pressure feeding devices 1. Underfeed roller (+10%) 2. Toothed roller pressure feeder(+15% - 20%) 3. Grooved roller pressure feeder(+20% - 25%)  Imbibition  Condition of mills  Personnel  Length of milling tandem

17 | P A G E

Calculation for mill capacity 𝐶=

0.9 ∗ 𝐶𝑝 ∗ 𝑛(1 − 0.06𝑛𝐷)𝐿 ∗ 𝐷 ∗ √𝑁 𝐹

Where, C =Capacity of the mill tandem in T.C.H. Cp = Coefficient of cane preparation=1.1-1.3 n=Roller speed in R.P.M N =No.of rollers in the tandem D =Diameter of the roller L =Length of the roller F = Fibre content per unit of cane Mills Mill Size(inch) Size of underfeeder Top Roller Angle Depth/ Pitch(mm) Feed Roller Angle Depth/ Pitch (mm) Disch. Roller Angle Depth/ Pitch(mm) UF Roller Angle Depth/ Pitch(mm)

Zero Mill 42”*84” 42”*84”

1st 36”*78” 36”*78”

2nd 36”*78” 36”*78”

3rd 36”*78” 36”*78”

4th 36”*78” 36”*78”

40

50

50

50

50

54/50

42/50

42/50

25/30

25/30

35

35

35

35

35

63/50

63/50

63/50

38/30

38/30

40

45

45

45

50

54/50

48/50

48/50

28/30

25/30

40

50

50

50

50

54/50

42/50

42/50

25/30

25/30

18 | P A G E

Journal Dia 600 (mm) Journal 700 Length

Drive Drive Detail s Make Powe r R.P. M

480

480

480

480

630

630

630

630

Zero Mill

1st

2nd

3rd

4th

ABB 750Kw(A. C) 1000

IEC 600Kw(D. C) 1000

IEC 600Kw(D. C) 1000

IEC 600Kw(D. C) 1000

IEC 600Kw(D. C) 1000

ROTARY SCREEN There is two rotary screens 1. One rotary screen make by Suviron capacity 227 MT/Hrs.Size Ǿ1800 x 3600mm. Screen size 0.5mm. Driven by 10 HP motor with 1440 RPM. 1P- 55 type gear box. 2. 2nd rotary screen make by Uttam Industrial Ltd capacity 310 Mt/Hrs. Ǿ1900 x 4500mm. Screen size 0.5mm. Driven by 10 HP motor with 1440 RPM. 1P- 55 type gear box.

19 | P A G E

INTERMEDIATE RAKE CARRIERS Totally there are 3 Inter rake carriers and 1 Bagasse elevator Zero mill Inter rake carrier made by Uttam Industries of Size 10.82 mtr. Length x 2.03mtr width. Linear speed of carrier 26.0mtr/min. VFD drive motor 50HP, 1440 rpm, and shaft mounted planetary gear box. 3 other intermediate rake carrier are 12 Mts in Length and has a speed of 3 m/min. Motor capacity 30 KW with VFD & 1440 RPM.Running by 4 stage H3-250 type Premium make gear box.52.1/1P1 1 Bagasse Elevator by Elecon Engineering Co. Ltd of 2000 mm. width and length of 20000 mm. Driven by motor of Alstom Make, 30 KW and 1470 RPM electric motor coupled to gear box of Elecon Make, Type: SCN 225, Ratio50/1.Gear box leaner speed 30.8 Mts. /min. Mill House Pump and Motor Details Pump and Zero Motor Mill Details Make Sintec h

1st

2nd

3rd

4th

Kirlosk ar

Kirlosk ar

Kirlosk ar

Kirlosk ar

R.J pump Imbibiti on pump SamTurb Kirlosk o ar

Capacity( m3/hr) Head

260

180

180

180

180

250

80

15

15

15

15

15

70

50

Speed

980

980

960

970

980

1470

1475

Power(K w/hp)

30/41

22Kw

30HP

15HP

15HP

75HP

30HP

20 | P A G E

Rotary Juice pump Geeta & KSB 35&3 0 40&5 5 2900 &289 0 15&1 2HP

IMBIBITION: Even when bagasse is subjected to high and repeated pressures, it never gives up all the juice which it contains. It approaches a minimum moisture, 45% in general, 40% in the most favourable cases; that is, it retains a high proportion of juice, amounting roughly to half its weight. In order to extract as much as possible of the sugar which it retains, it is therefore necessary to resort to an artifice: since this moisture content cannot be reduced, the effort will be made to replace by water the juice comprising it.It is this artifice which constitutes "imbibition". This system when used in each mill consumes much water, which has to be evaporated later. Starting from single simple imbibition, it has been observed that the dilute juice obtained from the last mill is mostly water; it has then been taken and sent back before the preceding mill. This is what is called "compound imbibition". Compound imbibition using Hot water of 70° C to 80° C. through pump is used through Flow meter. Capacity 0 to 150 m3/Hr.

MILL HYDRULIC SYSTEM -: One complete set of 8 nos. hydro pneumatic cylinders are provided for mill hydraulic system with oil storage tanks and pumps. Total hydraulic load applied on the top rollers of the mill is 160 to 180 kg/cm2 (g). Bagacillo Blower Fan There is two lower fans below the bagasse elevator to elevate the fine bagacillo particles passing through a .3mm sieve to the rotary vaccum filter.It

21 | P A G E

is of Airochem Industrial Fan make, S-1920 model. Driven by 15 HP motor with 1800 RPM, 5560 M3/Hr capacity. ACCUMULATOR When the mill is in operation, it will be overloaded in sometimes due to variation of load (when big amount of sugar cane pieces comes). In that case mill undergoes impact loads and however mill should be able to withstand them. To do this job, the damping system shown below is there. With this system the mill has a damping action and the mill can self-adjust the gap between the rollers. When more cane come, the top roller will tend to go up and gives force to the piston. This will send more oil in the accumulator, increasing the pressure of oil. The N2 is maintained at high pressure (200 kg/cm2) so it will re-expand and reject the oil, sending the piston down along with the top roller, again giving more force to the roller in order to keep the cane under equal pressure. The pressure can be increased by setting up the accumulator, even when the mill is working. Other settings can be changed only when the mill is stopped. Rollers have different depth grooves. This also will influence the mill performance and the mill wearing. For instance if the trash plate is too close to the roller, it will get worn and after that the extraction will decrease & is occurring more power loss.

22 | P A G E

MILL SANITATION Mill sanitation is important because Juice provides ideal media for growth of micro-organisms such as Dextran on mills. Sucrose is converted into reducing sugar by their enzymatic activity. The microbial activity is indicated by observing the purity drop Primary Juice to Mixed Juice which varies from 1.5 to 2.0 unit. The loss may not be completely avoidable but it can be minimized by using mill sanitation.

MEASURMENT OF WEIGHT OF RAW JUICE Mass flow meter with V.F.D. Juice stabilization System. Raw juice tank capacity 300 MT/Hr.

23 | P A G E

Mill House Calculations Capacity

𝐶=

0.9 ∗ 𝐶𝑝 ∗ 𝑛(1 − 0.06𝑛𝐷)𝐿 ∗ 𝐷 ∗ √𝑁 𝐹

Where, C =Capacity of the mill tandem in T.C.H. Cp = Coefficient of cane preparation Leveller & Fibrizer – 1.16 Leveller, Cutter & Shredder – 1.22 n =Roller speed in R.P.M N =No.of rollers in the tandem D =Diameter of the roller L =Length of the roller F = Fibre content per unit of cane

𝐶= 𝐶=

=4 = 4*5 = 20 = 1.08m = 2.15 m = 0.14

0.9 ∗ 1.22 ∗ 4(1 − 0.06 ∗ 4 ∗ 1.08)2.15 ∗ 1.08 ∗ √20 . 14

33.78 0.14

C=241.3T/hr

24 | P A G E

Brix Curve 𝑤 𝑓 Where w = imbibition % cane =30 f = fibre % cane =.14 𝑆=

S=

30 14

= 2.14

Brix obtained from lab analysis Feed roller 19.5 10.08 Discharge 19.42 10.82 roller Solids in Secondary juice =

5.85 6.69

3.21 3.94

1.98 2.11

(1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁−1 ) (1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁 )

Where N = No of mills in the tandem 17.5199 Mill No 2:

(1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁−1 ) (1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁 )

(1+2.14+2.142 +2.143 ) (1+2.14+2.14 2 +2.14 3 +2.14 4 )

Mill NO 3: =

(1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁−1 )

(1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁 ) (1+2.14+2.142 )

(1+2.14+2.14 2 +2.14 3 +2.14 4 )

Mill no 4: =

=.455

= 0.200

(1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁−1 ) (1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁 ) (1+2.14)

(1+2.14+2.14 2 +2.14 3 +2.14 4 )

= 0.0815

25 | P A G E

Mill no 5: =

(1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁−1 ) (1+𝑆+𝑆 2 +𝑆 3 +⋯.+𝑆 𝑁 ) (1+2.14)

(1+2.14+2.14 2 +2.14 3 +2.14 4 )

= 0.026

Ideal Brix Feed 19.5 19.5*.455=8. roller 87 Dischar 19.4 19.42*.455= ge 2 8.84 roller

25

19.5*0.2=3. 9 19.42*0.2= 3.88

19.5*.0815=1. 59 19.42*.0815=1 .583

19.5*.026= .5 19.42*.026 =.5

BRIX CURVE

20

15

10

5

0

1st mill

2nd mill

3rd mill

4th mill

5th mill

Ideal Curve

19.14

5.93

1.818

0.53

0.126

Actual Feed curve

18.96

7.12

3.64

1.71

1.11

Actual discharge curve

18.23

8.73

4.98

2.71

1.57

26 | P A G E

MILL EXTRACTION: It is the ratio of sucrose in Mixed juice to sucrose in cane.Higher the value better the efficiency. 11.98 𝐸= = .94 12.68 REDUCED MILL EXTRACTION Fibre % has an important role in extraction.As such while comparing effiencies of two milling plant the fibre % cane should be reduced to a standard 12.5 fibre % cane. 𝐸12.5 = 100 −

(100 − 𝐸)(100 − 𝑓) 7𝑓

= 100 −

(100−95)(100−14) 7∗14

= 95.6

Mill Sanitation Factor=

=

100 𝑅.𝑀.𝐸

∗

𝑃.𝐽 𝑃𝑡𝑦(100−𝑀.𝐽 𝑃𝑡𝑦) 𝑀.𝐽 𝑃𝑡𝑦(100−𝑃.𝐽 𝑃𝑡𝑦)

100 82.35 ∗ (100 − 80.84) ∗ 0.94 80.84 ∗ (100 − 82.35) = 117

A value above 100 is considered good.

27 | P A G E

BOILING HOUSE

28 | P A G E

BOILING HOUSE Juice Heater: Juice leaving the extraction plant is close to ambient temperature if a milling tandem is installed or at about 60˚C in the case of a diffuser. Filtrate is either returned to the raw juice tank, thus inflating the juice temperature somewhat, or to an intermediate tank after primary juice heating. The quantity of filtrate can vary from 5% to 25 % of the raw quantity, depending largely on the suspended solids content of the juice and the consistency of the mud withdrawn from the clarifier. The objective is to heat the juice up to a temperature a few degrees above boiling point just before the clarifier. The juice is then flashed in a flash tank, so that the juice temperature to the clarifier is always constant and dissolved gas in the juice is removed.The juice is generally heated in two or more stages, making use of lower pressure vapor in the first stage to improve steam economy. Thus most of the heat transfer considered here involves condensing vapour to achieve the heating required, though in the case of raw juice at lower temperature from a milling tandem, the first stage could be heating the cold juice with condensate from the evaporators. This saves steam and is useful in cooling down condensate if cooled imbibition water is desired and in providing cooled condensate for flocculant preparation. Juice heating is still mostly carried out using shell and tube exchangers or tubular heaters. Plate and frame heaters, generally known as plate heaters, are finding increasing use. Other types of heaters in use are platular heaters, and direct contact heaters, where the vapor is condensed in the juice to be heated. REASONS FOR RAW JUICE HEATING: Sulphide scales are formed under anaerobic conditions at temperature below 60°C. The formation of sulphides badly corrodes the metal surfaces of M.S. & brass tubes. Change of reaction and heat coagulates certain colloids. Albumin and certain other gelatins are dehydrated, denatured and coagulated by heat alone and are precipitated out. Reaction at lower temp than the optimum allowed delay the flocculation of colloids, which are not granular

29 | P A G E

and easy to filter. Due to heating of juice the phosphoric acid is precipitated as tri calcium phosphate with reaction of lime instead of Dicalcium Phosphate. Heated juice with lime precipitates more nitrogenous Matters. Reaction time with lime is very less due to heating of juice. Liming in heated juice is the only remedy to prevent the juice from being infected with Leuconostoc Mesentroroides & Mesophyllic bacteria. Raw juice temp. Should not go beyond 80°C, because of danger of inversion. The gums, wax and albumin made raw juice rather viscous and these impurities cannot be removed if the juice remains cold. CLEANING OF JUICE HEATER: Stop the Exhaust / Vapour valve, drain the juice. Recycle once the cold water and drain the same. Open both the cover plates. Descale the tubes using cutter in first round and then by brush. After ensured cleaning juice heater being tested by hydraulic test. If no tube leakage found, close the doors. Then check for body leakage. Open the Exhaust steam / vapour valve simultaneously with double beat valve. Start the condensate pump and non-condensable gas removal should be crack opened. Vapour Line Juice Heater Heating Surface Area 250 310 Size of tube 45*42 45*42 Height of tube 4000 4000 No of tube no of passes 504 580 No of pass 24 20 Tubes /pass 21 29 Final Juice 35-42 35-42 temperature(˚C) Steam is received from the last body of the evaporator

30 | P A G E

Duplex Juice Heater Heating Surface Area 250 125 Size of tube 45*16 45*16 Height of tube 5100 5100 No of tube no of passes 368 184 No of pass 8 4 Tubes /pass 46 46 Final Juice 45-56 45-56 temperature(˚C) The source of heat is the condensate water from the 2nd body evaporator. Dynamic Juice Heater Heating Surface Area Size of tube Height of tube No of tube No of pass Tubes /pass Final Juice temperature(˚C)

250 45*42 4000 504 24 21 70-75

310 45*16 4000 580 20 29 70-75

The steam used here is the steam from 3rd body and outlet of this body is also steam rather than condensed steam,which is fed to 4th body. The juice from here is sent for juice sulphitation. Sulphited Juice Heater Heating Surface Area Size of tube Height of tube No of tube No of pass Tubes /pass Final Juice temperature(˚C)

350(S.J.H)

310(S.J.H1)

310(S.J.H2)

45*16 4000 680 20 29 80-85

45*42 5100 464 26 18 90-92

45*42 5100 464 26 18 100-102

31 | P A G E

Sulphited juice heater 1 uses steam from the 2nd body evaporator while juice heater 2 uses steam from Semi kestner. Juice from here is sent to clarifier. Clarified Juice Heater Heating Surface Area Size of tube Height of tube No of tube No of pass Tubes /pass Final Juice temperature(˚C)

180

180

45*42 5100 288 16 18 110

45*42 5100 288 16 18 110

Clarified juice heater uses steam from Semi kestner. Juice from here is sent to Evaporator.

Cross sectional view of Juice Heater

32 | P A G E

Liming Liming is a main part of the Juice treatment. It set the PH of the clarified clear juice into 6.8 – 7.2 range. Therefore mix juice pH is set to (8.0-8.2). Because when the PH is lower sugar is convert to glucose and fructose by enzyme. Enzyme C12H22O11 + H2O C6H12O6 + C6H12O6 Sucrose glucose fructose The other purpose of liming is coagulating mud particles in the clarifier Normally a good lime contains 90-95% of CaO; in that case 400mg/L of clarified juice is required. The brix value of lime solution is 16. MILK OF LIME PREPARATION Capacity

1200 kg/hr (lime slaker)

2 number of MOL tank

200 HL

2 MOL pumps (Capacity)

12 m3/hr

Head of pump

20 m

Speed

6-8 R.P.M

QUALITY OF LIME:The Quick Lime coming to the factory should follow the following specifications. Active CaO

:

Above 80 %

MgO

:

Below 1%

Iron & Alumina

:

Below 2%

Silica

:

Below 1 %

Sulphates

:

Below 0.5 %

Moisture

:

Below 1% 33 | P A G E

Concentration of MOL

:

12.5o Bx Grit % of MOL : Below 7 % Chemical reaction LIME STONE TO LIME CaCO3 = CaO + CO2

LIME WITH WATER CaO + H2 O = Ca(OH)2 + 15.2 Kcal

Sulphitation Sulphitation processes are subject to almost as many modifications as simple defecation. The variations may include the following: 1. modifications of the sequence of addition of lime and SO2 (liming first, sulphiting first, simultaneous addition of lime and gas, fractional procedures); 2. temperature modifications (sulphiting cold or hot, stepwise heating); and 3. addition of reagents (batch, continuous, with either manual or automatic control). Obviously these variables permit a large series of combinations, and only the most commonly used are outlined here.

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COLD SULPHITATION The cold raw juice is pumped through a tower or box with a counter-current of SO2 to absorb as much gas as possible (acidity 3.0-4.0 ml 0.1 N alkali for 10 ml of juice; pH 4.0 or below). Liming to slight acidity (pH about 6.5) is followed by heating, settling, and decanting as in the defecation process. Evaporation to a thin syrup follows, and the syrup is settled for 6-24 h before vacuum pan boiling. One boiling, yielding a near-white sugar that is heavily washed in the centrifugal, is frequently followed by a second boiling to a raw sugar. The "boil-back" molasses is allowed to settle for several weeks before it is placed on the market. The success of the process is largely dependent on the quality and price of this molasses. Sulfitation can also be carried out by injecting SO2 (industrial liquid SO2 in cylinders) into the cold raw juice to a level of about 400 ppm SO2. This is for the production of raw sugar and A molasses. The A molasses is inverted to yield a sucrose-invert ratio of about 1:1, giving a total sugar of 65% at 80 Brix, with an SO2 level of 30-40 ppm.

SULPHITATION AFTER LIMING This process is termed alkaline sulphitation as opposed to acid sulphitation previously described. It uses about 8 gal (30 litre) of 26 Brix milk of lime per 100 gal (378 litre) of juice giving a large excess of lime. Sulphitation is then carried out to about pH 7.5 producing a heavy precipitate that may be removed with settling and decantation. Heavier liming (10-12 gal, 38 - 45 litre), will result in a precipitate that permit filter-pressing. After evaporation the syrup is cooled and sulphited to slight acidity (pH 6.5). Treating diffusion juice with lime and then sulphitation decreases the colour of syrup, raw sugar, and refined sugar by 25% 46% and 35% respectively The filterability is improved and molasses purity is lower, giving better sugar recovery

HOT SULPHITATION Hot sulphitation serves to reduce the solubility of calcium-sulphite, which is more soluble at low temperatures, the minimum solubility is at about 75°C (167 °F). The juice is first heated to this temperature then sulphited and limed boiled, and settled. Harloff's process is a hot treatment procedure in which the juice is heated to 75 °C and the lime and SO 2 are added simultaneously in such a way as to maintain the reaction acid to phenolphthalein and alkaline to litmus (pH about 7.4-7.8), except toward the end, when a quantity of lime is added to attain a strongly alkaline reaction (pH 10+), after which the sulphitation is completed to neutrality to litmus (pH about 7.2). As in all other similar processes, the juice is finally brought to boiling temperatures in juice heaters and settled.

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CONTINUOUS SULPHITATION Continuous sulphitation means the continuous addition of SO2 and lime to the constantly flowing stream of juice. Marches shows many different procedures with diagrams indicating construction details, methods of lime and gas addition, baffles to ensure proper circulation and other details. Many of the continuous liming processes may have different fractional procedures, but are not in general practice.

SULPHITATION OF SYRUP Sulphiting the syrup leaving the evaporators gives a sugar of higher and more regular quality than juice sulphitation alone. The syrup density is lower than in ordinary defecation processes, 55 Brix against 65 Brix or higher Sulphited syrup is usually maintained at a distinct acid reaction, pH 6.1 - 6.5.

CONTROL OF TEMPERATURES AND REACTIONS Good circulation and thorough mixing both of the lime and of SO2 are very important A bent circulation baffle devised by Thompson gives the best results in cylindrical sulphitators Avoidance of high alkalinities at high temperatures or for extended periods is recommended for the same reasons as in defecation control: such high alkalinities result in decomposition of reducing sugars and in colour formation. Poor mixing of lime and juice may produce local over-liming. Temperatures above 75 °C are detrimental and some prefer not to exceed 70 °C until the final pH adjustment is made, to give a clarified juice to the evaporators of pH 6.9-7.0.

SULPHITATORS Generally the mixed cold juice is sprayed into tall vertical cylindrical tanks, 4ft (1.2 m) or more in diameter and possibly 15 ft (4.5 m) high, fitted for the upper two-thirds with a series of hardwood grids made of 2 x 4 ft (0.6 x 1.2 m) timbers set on edge. The juice enters the top of the tower in a spray and falls through the wooden grillwork, where it encounters the rising current of SO2. Either the flow of gas through the system is induced by an air ejector or the SO2 is under pressure. The sulphitated juices are drawn from the conical bottom of the tower at a pH of 3.8-4.0, limed in a separate liming tank to pH 6.5-6.8, then heated to boiling and settled. Continuous sulphitation can be carried out in cylindrical sulphitators holding a fixed volume of juice. Heated juice (75 °C) flows through the tank continuously, while the milk of lime is added constantly to the entering juice and a continuous pressurised flow of SO 2 into the liquid near the bottom of the tank supplies the needed circulation. The supply of gas is kept constant, and the lime addition is regulated by a controller. In actual practice,

36 | P A G E

the juice is pre-limed before entering the sulphiting tank, generally to neutrality, then is maintained near the neutral point by the sulphitation-lime addition. Zozulya et al. describe a new sulphitator which comprises a vertical tank with a feed-line at right angles to the top of the side wall. The juice is fed into the feed-line through a perforated disc and comes into contact with SO2 gas metered through a valve at right angles to the liquid stream. An internal cyclone at the top of the tank acts as exhaust gas-liquid separator and as supplementary mixer for the incoming gas and the juice. Performance data of this new design show results superior to the conventional spray type with better gas utilisation and decolourisation.

SULPHITATION WITH BENTONITE A process employing colloidal bentonite combined with sulphitation was developed in Argentina for the production of direct-consumption white sugars, especially with juices of deteriorated or frozen cane. Bentonite is a clay, and the material selected is sold in Argentina under the trade name Clarigel. The advantages claimed are lower sulphur and lime consumption, much greater removal of organic non-sugars, better boiling properties of syrups and molasses because of reduced viscosities, and less scaling of evaporators.

SULPHUR STOVES OR BURNERS The production of SO2 occurs when sulphur is burned in a current of air. Older-type stoves operate intermittently; modem burners provide for the addition of sulphur without interruption of the burning. In any type of sulphur burner the air supplied to the furnace should be dry, because moisture in the air will cause the formation of sulphuric acid, obviously detrimental to piping, and soon, and can be especially serious if it reaches the juice. The drying agent is generally quicklime spread on trays, and it should be replaced before it becomes saturated with water, about every 8 h. Rotary sulphur burners use induced draft. Mechanical feed ensures continuous operation. Best results are obtained with sulphur of high purity (99.6-99.9%). The sulphur melts by its own heat of combustion in the rotating cylinder, presenting a large surface for combustion as the sulphur drips through the air. Air is drawn in at an adjustable neck ring and anti-sublimation sleeve at the connection between the rotating drum and combustion chamber, a cast-iron or brick lined compartment with baffles, where the oxidation of the sulphur and mixing with the diluting air are completed. A uniform gas (5-16% SO2) free of sulphuric acid is delivered to the sulphitators. There are new methods of SO2 generation. The Swedish Celleco SBM-250 sulphur burner

37 | P A G E

has a burning capacity of 5 t/d but has a turn-down ratio of 20:1, or 250 kg/d. It is normally operated at 2.0-3.0 psig, but can also function effectively at 42 psig. A typical flow scheme for a modern SO2 generation plant is given

LIQUID SULPHUR DIOXIDE Where transportation costs will permit, liquid SO2 offers many advantages. MeGinnis diagrams a system for the introduction of liquid SO2.

38 | P A G E

The method is comparatively troublefree and adapts itself readily to automatic pH control. A large reduction in sulphur consumption results; freedom from sulfuric acid, precise control of SO2 addition, and elimination of sulfur-burning equipment are other advantages. HYDROGEN PEROXIDE Hydrogen peroxide has also been tried in sugar refining. and reduced white sugar color by 46% and ash by 20%. CURRENT TECHNOLOGY The carbonated liquor after the first filtration still contains an appreciable amount of calcium in solution which has to be removed. This is done. by treating the filtrate with sulphur dioxide to form calcium sulphite precipitate. The latter is then separated from the liquor during a second filtration to produce a final clear liquor. Sulphitation is not an essential part of a carbonatation refinery, another Process such as ion-exchange can also be used to remove excess calcium. EQUIPMENT Because sulphitation is only a minor operation in a carbonatation refinery, geared mainly to reducing excessive alkalinity to the neutral point, the amount used is relatively small and the apparatus sometimes a bit crude. especially the sulphur burner. The equipment in use in our refineries to perform liquor sulphitation consists of: 1. the sulphur burner for production of SO2 gas 2. a tower for contacting liquor and SO2

or a venturi system of contacting, such as the Quarez sulphitator. DESIGN CONSIDERATIONS Sulphur burner, Production of SO2 gas: The combustion of sulphur is required to produce sulphur dioxide, because the reaction takes place in the gaseous state between sulphur vapour and oxygen, according to the formula: S + O2 → SO2 + 293 kJ The reaction is exothermic and the combustion gas has an SO2content of 6 to 16%. A simple type of sulphur burner is normally used being of the stationary type and quite suitable for the light sulphitation of liquor required. Ideally the design and operation of sulphur burners require that some important points be recognised, in particular:

39 | P A G E

1. Keep to a minimum the formation of SO3 which will react with moisture in the air to produce sulphuric acid. The cooling of SO2 gas to below 200°C is essential, the production of SO3 then being negligible (5). The, drying of the air of combustion is also required to prevent the formation of H2SO4. 2. Prevent the sublimation of sulphur, which can cause blockages and impair SO2 production by controlling the furnace temperature to less than 300°C. 3. The air flow should be kept constant and controlled. 4. A regulated supply of sulphur should be provided, if possible. The points mentioned above are not easy to control in the type of furnace in use, but then the operation is not critical enough to warrant a more complex approach. THE SULPHUR TOWER As the name implies this is a tower containing splash trays, stacked on top of one another and designed to create a continuous passage for the liquor from the top to the bottom, while the SO2 gas travels up the tower. The liquor is broken into droplets in falling from one splash tray to the next. The gas is drawn up the tower by suction from a fan and the exhaust fumes are dispersed into the atmosphere. Reaction takes place as the SO2 conies into contact with the liquor. The sulphited liquor, with calcium sulphite precipitate in suspension, exits the tower at the base into a small seal tank, since the tower is under slight vacuum. THE QUAREZ The Quarez sulphitation system consists of a holding tank, a circulating pump, a venturi and sulphur furnace to produce SO2 The level in the tank is kept constant by means of an overflow. Liquor in the holding tank is circulated by the pump and a certain amount is forced through an injector creating a vacuum, which causes the SO2 gas to be sucked in and mixed. The rest of the liquor by-passes the injector by means of an adjustable valve, the setting of which controls the amount of gassing and the final pH of the liquor. PRACTICAL CONSIDERATIONS

Operating control Sulphitation is carried out to a pH of 7.0 and even at 6.9 – 6.8; but a lower pH than this will result in inversion of sucrose and must be avoided. It is therefore of paramount importance to reliably control the final pH set point. This is generally done by varying the proportion of SO2 gas to liquor by measuring liquor pH.

40 | P A G E

Filtration Filtration of the sulphited liquor should take place at or near 85°C to take advantage of the decreasing solubility of calcium sulphite at high temperatures as well as lower viscosity. A heat exchanger of the shell and tube type is normally used for this purpose. The amount of calcium sulphite precipitate is much less than the carbonate precipitate and less filtering surface is required.

Operational information:

 Melter and feeder: Dry sulphur is melted in melter and molten sulphur is taken into feeder. Both vessels are steam jacketed (there will be a steam jacket) charging and feeding valves are of gun metal both the valves should not be kept open at time.  Combustion chamber /furnace. Molten sulphur is feed to t6his combustion chamber it is made of cast iron [C.I] and water jacketed on the top. The compressed air inlet is near the entry of sulphur melt and so2 gas outlet will be from other end. The temperature is around 450 degrees to 550 degrees.  Coolers: This comprises of CI pipes with water jacket and used for cooling the hot SO2 gas.  Scrubber: It is water jacketed cylindrical tank and packed with bricks gas inlet is at the bottom and allowed to rise through the layers of bricks to trap the sublimed sulphur the outlet gas temperature should be 60 to 70 degrees.  Air dryer and air compressor: Air drier is required to supply dry air to the compressor the air compressor supply air at a pressure of 0.6 kg/cm2. And 4.3 kg of oxygen is required to produce I kg of sulphur.  Preparation of sulphur-di-oxide: Sulphur melting point is 115 degrees so2 gas is generated by burning sulphur in excess of air in sulphur burner. The reaction takes place at a temperature of 365 degrees the temperature of the furnace is maintained around 400 degrees to control the furnace temperature and water is circulated over top tray of furnace. S+O2 ------- SO2 + HEAT

The gas generally contains 12 to 16% SO2 depending on the proportion of the air used. The continuous type sulphur burner is suitable for burning 70 Kgs per hr. of sulphur. Each burner having a 0.6 sqm burning area. The melting

41 | P A G E

chamber of burner is made of 12mm thick MS plate. The combustion chamber is 16mm thick. The burner connects with electric motor drive stirrer, water jacket counter current cooling arrangement for the vertical gas, pipe, scrubber etc. SO2 lime from the entire burner is installed so that both syrup and juice could be sulphited from any of the furnace either separately or jointly. E.I.D parry Bagalkot has: 1 No. Film type sulphur burners, digitally controlled of 200 kg/hr. capacity. 1 No. Auto continuous sulphur burners, 70 kg. /hr. capacity. 1 No. Auto continuous sulphur burners, 40 kg. /hr. capacity. ONE E-MELT: One E-Melt system make by Digital Utilities. The operating

pressure 6.0 Kg/cm2, Hydro Pressure 9.0 Kg/ cm2, Operating temperature 150°C & Radiography 100%. JUICE SULPHITATION

Size Capacity(H.L) Absoption Ligament Retention Time Stirrer R.P.M Drive H.P R.P.M

No:1 Ǿ 3850*5515 mm 250

No:2 Ǿ 3000*4732mm 250

Ǿ1200*3133H

Ǿ1200*3730H

50 7-8 mins 16 15 960

50 7*8mins 16 10 960

42 | P A G E

Flash tank Clarifiers are normally preceded by a flash tank. This is a simple cylindrical tank placed just above and ahead of the clarifier, with a flue open to the atmosphere.

Clarifier The next important step is clarification. Without good clarification of cane juice, can’t produce good quality sugar. A clarifier is used to separate out the solids suspended in the cane juice. These solids originate from sand adhering to the cane stalks as well as from material inherent in the cane stalk. The separation takes place by allowing the solid particles to settle out onto a tray. The solids are swept from the tray into a mud compartment, from which it is pumped to filters for desweetening and dewatering. During the purification all non-sucrose is separated and sends out of the factory to manufacture compost fertilizer. After clarification clarified juice sent to the evaporators father treated using DSM screen for produce syrup. Muddy juice is filtered using rotary vacuum filter.

43 | P A G E

OPERATIONAL INFORMATION:

The factory has a 444 clarifier of 36 feet * 20 feet having a capacity of570 m3. This 444- Door consists of one flocculating chamber at the top and 4 juice compartments, each compartment consist of mud draw and juice overflow line. The treated juice after heating upto 102˚C – 105˚C is fed into the flocculating chamber of the Door through a flash tank. The flash tank is provided with a U-shaped outlet which connects the flue chamber to reduce the velocity of the juice which otherwise will disturb the settling in the clarifier. Treated juice enters the clarifier through the flash tank, when the isolation valve is the controled. Shaft of the second, third and fourth compartment successfully when the juice in the Door reaches the overflow level it can be converted to work as 444 Rapi-Dorr single Dorr by closing isolation valve. When the clarifier is working (fed continuously mud will settle in all the compartments. Mud can be drawn from the compartments simultaneously. The advantage of working the clarifier 444 as Rapi-Dorr single Dorr is to get a clear and brilliant juice. In the case of liquidation of juice from the clarifier the 444-Dorr should be converted into single Dorr. There is a central shaft being rotated by a drive mechanism. The central shaft is connected to the arms of each compartment which have scrapper blades to scrap thick mud settled without disturbing the clear juice. The mud and clear juice are drawn from the clarifier by overflow. The clarity and the color of the clean juice is good and the juice is of golden yellow color. During shut down Milk of Lime is added to the clarifier to maintain the pH of clear juice at 7.0. Formaldehyde is also added to minimize the sugar loss in clear juice due to inversion. Though the treated juice is heated upto 105˚C the temperature of clear juice coming out of the clarifier is only 96-98˚C. The drop in temperature is more than normal. Vent pipes are provided (3”) to all the compartments apart from the vapour releasing pipe from the flocculating chamber to the atmosphere. An inclined chute of (5 to the horizontal) 1½ feet width and fleet weight is connecting mud overflow box and the flocculating chamber to remove the form and other suspended materials if any the cylindrical portion and perfectly lagged. All the juice and mud drawl pipelines are also protected with lagging material.

44 | P A G E

MUD FILTER

The clarified mud still has sucrose close to 5% and is produced in large amounts, so it is not acceptable to run it to waste. The mud is filtered by rotary vacuum filters in order to recover the sucrose contained inside. PLSI use a rotary vacuum filter for mud juice filtration. The filter consist of a very small holes 625 holes per square inch, each of 0.5 mm diameter. It is inside divided into 24 sections of 15° each. The compartments are under vacuum but connected independently to the vacuum system. The drum is turning slowly (around 1 rpm). Hollow rotating drum covered with a perforated plate of stainless steel which partly dips into a bath contain the mud juice. The drum is rotated a horizontal axis and suction is applied to the different segments forming the thick cake on the filtering surface. There is large number of pipes inside of the rotating drum, these pipes is used to remove filtrated juice from 45 | P A G E

drum. All pipes are connected to distribution valve which is located at the center end of the drum. It is divided into three independent sections. Therefore there are three vacuum segments on filter, here under 1. Low vacuum zone(Suction) 2. High vacuum zone(Washing) 3. No vacuum zone(Remove mud) Low vacuum zone is submerged in the mud juice agitator bed, it is used to hold the weight of slurry and support the weight of drum in operation. Agitator is used to keep the slurry always is suspension and prevent it from setting. Mud agitator bed is included over flow connection from both ends and feed inlet connection. Wash of cake is done by sparing hot water at high vacuum section. It is done using seven drip pipes; each drip has a row of number of holes. To wash the cake efficiency reduces the pol losses in cake without excessive consumption of water. When wash filter cake using hot water (>90 0C), sucrose molecule will break. Finally the filter cake is sent to the compost plant and the filtrate juice is sent back to the clarification.

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EVAPORATION In evaporation process we use heat to remove water from clarified juice where evaporator works as heat exchanger. Juice flows through tubes and steam gives heating effect from outside. It is most important to use steam effectively and also steam should be superheated to get a good heat transfer coefficient. By evaporation effect juice becomes syrup as sugar will becomes concentrated on heating. Evaporation process makes juice of 60 brix which further increases by pan boiling and crystallization.Now a days we are using multiple effect evaporator system where transmission of heat is fast and less use of steam is beneficial. This was first introduces by Norbert Rillieux in mid of 1800’s and so their principles called Rillieux principle. In the research he resolved the problem of heating juice at atmospheric pressure by 110°C temperature and 0.5 Kg/cm² pressure by putting first vessel under vacuum and thus it become possible to create necessary temperature difference and to utilize the vapour arising from the juice in the first vessel to heat the juice in the second vessel, the vapour produced in second vessel to heat the third and so on. Rillieux Principles of multiple effect evaporation First principle: In a multiple effect evaporator of N effects, one Kg of steam will evaporate N Kg of water. Second principle: If vapour is withdrawn from the ith effect of a multiple effect evaporator of N effects and used outside the evaporator system in place of steam, the steam saving will be i/N times the quantity of steam used in this duty. Third principle: Whenever steam or vapour is condensed, provision must be made to withdraw incondensable gases continuously. Vapour Bleeding In heat economy point of view vapour bleeding is very advantageous. As we know that in multiple effect evaporators, vapour of one body is used to heat next body and hence at the same time condenser load is also reducing. Since the vapour bleed have less temperature than exhaust steam thus to gain steam

47 | P A G E

economy the bleed would be chosen to come from latest effect possible is uses in pan boiling and juice heating.

Semi Kestner Body No of Length tubes (mm)

A B C

10256 3062 1824

2200 5100 5100

I.D and Dia of Size of O.D the body the (mm) vapour pipe(mm) 45*42 7030 700 45*42 4500 600 45*42 3860 600

Heating surface area(m2) 3000 2100 1250

The steam entering the calandria is the 2nd extraction steam from the turbine at temperature of 120˚C and .8 kg/cm2 pressure.

48 | P A G E

Second Body Body No of Length tubes (mm)

I.D and Dia of Size of O.D the body the (mm) vapour pipe(mm) A 1018 1272 45*42 6800 700 B 4214 2250 45*42 4700 600 C 3844 2450 45*42 3850 700 The steam in the calandria is at 110˚C and pressure of .4 kg/cm2 Third Body Body No of Length tubes (mm)

I.D and Dia of Size of O.D the body the (mm) vapour pipe(mm) A 4214 2250 45*42 4700 600 B 4214 2250 45*42 4700 600 The steam in the calandria is at 98˚C and vaccum of .2 kg/cm2 Fourth Body Body No of Length tubes (mm)

I.D and Dia of Size of O.D the body the (mm) vapour pipe(mm) A 2768 2450 45*42 3675 500 B 1684 2000 45*42 2900 500 The steam in the calandria is at 80˚C and vaccum of 180mm Hg Fifth Body Body No of Length tubes (mm)

I.D and Dia of Size of O.D the body the (mm) vapour pipe(mm) A 1684 2000 45*42 2900 500 B 1318 2000 45*42 2800 750 C 748 2000 45*42 2000 400 The steam in the calandria is at 65˚C and vaccum of 430 mm Hg

Heating surface area(m2) 2700 1250 1250

Heating surface area(m2) 1250 1250

Heating surface area(m2) 900 450

Heating surface area(m2) 450 350 200

49 | P A G E

Centrifugal type catchalls, with drain pipes, are provided in all the bodies. External save all in the vapour line from 5th. Body to condensor & Poly baffle entrainment arrester in the vapour extractor of Semi- Kestner, 1st A, 1st B, & 3rd body.

Syrup Clarification Due to the inferior quality of cane, sometimes clarification of syrup is not so good or poor. So, clarification of the syrup required and also there is a need because after evaporation when it reaches at higher brix there are some impurities which are becomes insoluble. Clarification of syrup by settling is not possible because of the high density and viscosity of syrup. So floatation clarification is established. In this method very fine suspended matter which will not settles have been floated off. The mechanism involves physical capture of air bubbles within the flocs. Scum can be floated of with bubbles in the clarifier. For this purpose phosphoric acid is added and flocculants is added. Temperature was also found to have a significant effect on turbidity removal. The optimum temperature of the syrup is 85˚C I. The syrup from the evaporator will be heated up-to 85˚ C by direct contact heater. II. The heated syrup will pass through the reaction tank, in this tank phosphoric acid, alezene & Nalco chemicals will be added. III. The syrup from the reaction tank will enter into the syrup clarifier, the syrup clarifier works on the inverse principle of juice clarifier. IV. Due to gravity high density syrup will settle on the bottom of the clarifier and low density muddy foam will overflow. V. The launders will move the foam into the discharge channel and the foam will sent to the juice Sulphitor.

50 | P A G E

Pan Boiling Pan boiling step results in the formation of sugar crystals. This then is the process of evaporating still more water from the syrup to produce what is called a massecuites. This is a very problematic and qualitative operation that has to be done by experienced people. The pan boiling operation take place water is evaporated and sugar crystals form. Indeed the product has to be uniform with the right size of crystals, without wasting syrup.

Finally the massecuites will then go to the centrifugal separation unit where the sugar crystals are separated from the molasses.

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Operational information: After Sulphitation of syrup, Syrup clarification , the syrup is subjected to vacuum pan boiling process. The pan boiling essentially consists of the removal of water by evaporation in single effect vessel known as vacuum pan &crystallizing out sugar by increasing the concentration. The function of vacuum pan is to produce & develop sugar crystals of desired size from syrup or the molasses known as mother liquor.  Height of pans: The Massecuite level above the top level tube plate of the pan should not be more than 1.5 meter A vapour space equal to 85% of the maximum height of the Massecuite above the top tube plate to the provided.  In-condensable gases: For better heat transfer the removal of noncondensable gases from vacuum pan Calendria is essential.  Syrup for molasses unit: Feeding to the pan is made by a pipe terminating in the center near the bottom.  Discharge valve: The discharge valve of a vacuum pan is provided for dropping Massecuite after completion of the boiling.  Numbers 5 2 2 Capacity 80T 60T 33.5,20T Duty for boiling 5 A pan boiling 2 graining , B,C boiling low head calandria Type Batch Type Pans, Continuous pans,

Heating Surface 398 m2 Area No of tubes 1607 Size of tubes 800*102mm

342,280

760,632

1630,1220 800*102mm

1382,2428 900*102

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Condensation plant Total 9 Number of Single entry S.S. condensing system with a Common header arrangement for quintuple and pan condenser. 02 Number of condenser pumps type WPC 100/325+J, capacity: 125 M3/hr., Head - 30 Mtrs. Motors: 18.5 KW/1450rpm. 4 Number of Centrifugal pumps, type MF 50x65 with a capacity of 20 M3/hr and Head: 30 Mtrs. The Motors is of 9.3 KW/1450rpm. There is also an injection pump type 8 AD 13.5 of capacity: 500 M3/hr and Head 30 Mtrs. Motors is of 55 KW/1450rpm. Water cooling system SPRAY POND Spray pond is a reservoir in which warm water from condenser comes and cools before use. This is done by spraying warm water with nozzles into the cooled air. Evaporation of water cools the water down before it reaches the pond surface. By this, temperature drop of 10 to 15˚C is achieved. 3 Number of Industrial cooling Tower( Hubli )Make 1 Induced Draft- counters flow cooling Tower of two stage cooling towers capacity 3200M3 ,2 cells,2 fans. Quantities per cell is 1600 M3/Hr. Two Pump of rating220KW, 1440 RPM, Cap. 1600 m3/ Hr. 1 No. Induced Draft counters flow cooling Tower of two stage cooling towers capacity 1600M3 of 1 cell and 1 fan. Quantities per cell 1600 M3/Hr. Two Pumps of rating 220KW, 1440 RPM, cap. 1600 m3/ Hr.

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CRYSTALLIZER Crystallizer is consisted of tube bank, heating room, juice and steam room, bottom cover and juice capture device etc. heating room is suspending drum type, using supporting member to suspend the heating room on the wall of the jar. The circular liquid descendent channel is formed between the heating room and wall of the jar. The central down comer makes the massecuite, which is raised by the heating in the heating pipe, is divided into inner circulation branch and external circulation branch on the tube plate. The heating room of the crystallizer uses the structure of incline tube plate. Up and down tube plate adopts the same angle of inclination. The bottom cover is taper one, using the electric valve to discharge the materials. The diameter of juice and steam room is bigger than the heating room; it can reduce the liquid level of the tube in down tube plate when boiling massecuite at same volume so as to reduce the effect of static pressure and strengthen the circulation of the massecuite. There is mechanical agitator installed in the forced circulation crystallizer. Driving the massecuite to make forced circulation in the container so as to improve the heat transfer coefficient and evaporation intensity also increase the speed of the crystallization. The agitator has top placing type and middle placing type. It is easy to discharge sugar and it owns relatively big liquid – descend cross section so its convection circulation rate is good and condensate water is fully discharged. VERTICAL CRYSTALLIZER This equipment is consisted of cylinder, cooling device, agitator, transmission device etc. it can be installed in open air, reducing the infrastructure cost. Moving components are installed on the centre vertical shaft which rotates among the heat exchange tubes, agitating massecuite and cleaning the cooling surface. The connector of cooling pipe is placed out of the vessel to avoid the cooling water leaking into massecuite. It is especially suitable crystallizing the C massecuite. There are multi-layer cooling snake tube in the machine and equipped with agitator, of which improved the cooling speed rate massecuite. So the generating the pseudo crystal is avoided. The main feature of vertical crystallizer is that it makes homogeneous cooling down; technical performance is stable and reliable. The average cooling temperature different is 2°C/hr. High capacity with less space required

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makes it more especial also it can reduce the purity of waste molasses about 4% comparing with horizontal interval crystallizer, improved the ratio of recovery of sugar. 2 Vertical crystallizers, 1 for B M/c of 250M.T while the other for C M/c of 300 M.T AIR COOLING CRYSTALLIZER This is a kind of air cooling crystallizer among the interval crystallizer series. It is crystallizing equipment for cooling and crystallizing the massecuite. It is suitable to be a storage container for A-massecuite before separating or for crystallizing of any massecuite. The equipment is consisted of U shaped body, agitator, transmission device etc. there are symmetrical left and right agitation plates that are installed on the long horizontal shaft, which prevents the crystal grain from sediment. The turning is driven by electromotor through the worm wheel reducer, massecuite reduce heat in open air by contacting with surface of metal shell, and cooling through the surface of the massecuite, which is exposed in the air, to reach the purpose of crystallizing. 5 U shaped Air Cooled crystallizer for A-M/c of capacity 90 M.T. each 4 U shaped Air Cooled crystallizer for B-M/c of capacity 85 M.T. each 1 U shaped Air Cooled crystallizer of 85 M.T. for C M/c. Seed Crystallizers : 2 For Dry seed For B-seed

: Cap-50 MT (stirrer RPM: 1, HP: 7.5) : Cap-50 MT (stirrer RPM: 1, HP: 5)

Vacuum Crystallizers : 4 a) 3 (AF-1, B-grain-1, and C-grain-1) 75 MT each (stirrer RPM: 1, HP: 5) b) 1 for A footing 30 MT (Stirrer RPM 1, HP 5)

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Centrifugal Operation After crystallization process we need to separate massecuite from the sugar crystals for which we uses high speed centrifugal machines. After centrifugal operation, if extracted sugar is high grade then delivered to drier house otherwise low grade sugar either be melted or return to pans for footing or as a seed. Types of centrifugal machine  Batch type centrifugal machine  Continuous type centrifugal machine Batch type centrifugal machine This type of centrifugal machines are being used for the purging of high grade massecuite. Batch type machine take the massecuite feed and discharge the sugar in batch operations. In batch machines there are two phases. 1. The initial purging and washing below spin speed. 2. Drying of sugar at spin speed. Here batch centrifugal machine is done for the purging of A-M/C. here double curing is done with in a single machine. Sugar discharges from the centrifugal goes for the hopper with 99.9 purity. A Heavy Molasses[70 pty] goes to the A heavy run off tank and A Light molasses[93 pty] goes to the A Light run off tank. 4 Batch Pans for A M/c single curing with Four speed fully automatic, Flat Bottom, WIL make, 1750 Kg. per charge capacity, DC driven IE make motor having speed based microprocessor control system.Sieve size is .35mm CAPACITY The capacity of batch centrifugal machine usually depends upon,  Time duration of cycle  Volume of massecuite in basket  The thickness of layer massecuite

Continuous centrifugal machines This type of centrifugal machines are being used for purging of low grade massecuite.

56 | P A G E

Special B-M/C curing Curing of special-B M/C is done in batch machine. Here B-seed sugar(96pty) discharged from the machine continuously and it magmaised with water and pump it to B-seed storage crystalliser in pan floor. The molasses(69-70 Pty) run off to the A-Heavy run off tank. 1 Four speed fully automatic batch type for B M/c Flat Bottom,WIL make, 1250 Kg. per charge capacity,centrifugal machines DC driven IE make motor having speed based microprocessor control system.

B-M/C curing Curing of B M/C is done in continuous machine. B single cured sugar (92 pty) discharged from the machine melted and sent to the melt storage tank in pan floor. The B heavy molasses (49 pty) goes to the B Heavy run off tank. Then pump it to the pan floor B heavy storage tank. 3 Continuous vertical WK 1500 of WIL make with basket diameter of 1500mm and RPM 1700, belt driven by 110 KW (75 HP) motor, Basket cone angle 30 deg. Gravity factor 1150 capacity (15 T/Hr).Sieve size is of .09 mm C-M/C curing C-M/C is double cured. First C-M/C cured in C-fore machine. C single cured sugar (84 pty) magmaised and sent to C-after pug mill. Molasses leaves the machine is the final molasses. Purity about 29. Goes to the final molasses run off tank. It cool down to 40oC then sent it to the molasses storage tank. From the C-after pug mill, C-fore magma feed into the C-after machine. Cure it into C double cured sugar (92 pty). Melt it and sent it to the syrup sulphitor. C light molasses(60 pty) goes to the run off tank and then pump it to the pan floor. 3 Continuous vertical for C-fore M/c WK 1500 of WIL make with basket diameter of 1500mm and RPM 1700,belt driven by 110 KW motor, Basket cone angle 30º, capacity 10 T/hr. having 3 Transient heater of 22 M2 H.S. each for heating C-Massecuite. Sieve size is .04mm 2 Continuous vertical for C-after M/c WK 1500 of WIL make with basket diameter of 1500mm and RPM 1700, belt driven by 110 KW motor, Basket cone angle 30 deg.Capacity 6-10 M. T./Hr. Sieve size is .06mm . 57 | P A G E

Operational information: The machine in which sugar crystals from the Massecuite are separated from the surrounding molasses or syrup by centrifugal force is called centrifugal machine. The centrifugal machine comprises of  Pug mills for Massecuite receiving:The pug mill is a u shaped provided in centrifugal section with constant stirring arrangement. At 5 to 6 rpm these pugmills are equipped with arrangement to keep the Massecuite in constant motion the level of Massecuite in pugmills is always kept at about 3/4th of the vessel so as to provide +ve Massecuite head when charging to centrifugal machine.  Transient heaters For heating low grade Massecuite upto saturation temperature a heat transfer unit used is called transient heater. A low grade Massecuite is heated uniformly with vapour oblique steam.  Magma mixersThe sugar separated from Massecuite after centrifugation is to be mixed with syrup or clarified juice or hot water to form magma. This is done in magma mixers these mixers are double padded type.  Molasses receiving tanks The molasses receiving tank are of usually one to two cubic meter capacity are of M S construction the function of these tanks is to receive the molasses from centrifugal machine and pumps this to huge molasses storage or supply tankers.  Air compressors For pneumatic controls air compressors with receiver is installed shall be of suitable capacity and is generally operated at a pressure of 6kg/cm2 to7 kg/cm2.  Pumps for magma /molasses This magma is pumped to a pugmills or sent to seed crystallizers or to Melter depending upon the boiling scheme with the help of pumps.  Water wash systemTo get better quality of sugar crystals a super-heated steam or a super-heated water is sprayed for washing

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CONSTRUCTION AND WORKING:

The basket of these centrifugal is in the form of an inverted cone with an angle of 30 and 34˚C, mounted with its axis vertical and driven by 'v' belts from a motor also mounted vertical. The basket rotates at speed of 1500 to 2100 rpm. The Massecuite is heated at 52˚C is fed in to the accelerating cup from vertical zero movement. The Massecuite is gradually accelerated while it is spreading out to the actual separating surface of the basket. This completely prevents damage to sugar crystal. In order to reduce the viscosity of Massecuite, the hot water or diluted final molasses is also added or sprayed with Massecuite for better centrifugation. This hot water or diluted final molasses prevent the Massecuite from adhering to surface of basket. The quantity of wash water used is about 35 –50 lit / m3 of Massecuite ( 2.5 to 3.5 % on mass max. ) with water pressure of 2 kg/ cm2 . It is specified that the wash water is to be applied with nozzle( having orifice of 1.2 to 2 mm ) at the lowest point of basket and it may be extended up by 150 to 200 mm. This length may vary as it will again depend upon Massecuite viscosity. The cold Massecuite when reaches near the bottom cone of centrifugal basket, strikes the bottom plate and it is thrown outwards against the wall of basket and get disintegrate in to fine stream and this fine stream passes over the working screen of centrifugal force get separated out and collected in molasses chamber. If required the use of secondary wash water or steam may be used (This may be done at 4" to 6" distance from bottom of centrifugal basket.)The angle of basket to horizontal is generally 30o for B Massecuite and 34o for C Massecuite. The speed of centrifugal machine used for B Massecuite is 1500 RPM, while for C Massecuite 2100 RPM and having a motor 45 KW. Basket is conical with sides at an angle of 28o to 34o from the vertical. Angle is chosen such that Massecuite will climb up basket screen under the influence of centrifugal force. The thickness of Massecuite layer is very small i.e. 2 to 5 mm and at the discharge it almost equal to the dimension of biggest crystal. Sugar is discharged over the top lip of basket whereas molasses flows through filter screen and out of inner casing via a molasses discharge pipe. There is stationing baffle or seal arrangement close to basket top lip to prevent remixing of molasses and sugar within the casing. Filter screen is located on a backing mesh in similar way to that of batch Centrifugal. Drive mechanism is simple belt drive. Basket speed ranges between 1500 to 2100 rpm with basket diameter from 1000 mm to 1500 mm (39" to 59").

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Vapour Bleeding For Process For Different Effect At Flow 240 TPH Crushing Rate

:

240 TCH

Mixed juice / Clear juice % cane

:

102 %

Quantity of M.J. / Cl. Juice

:

244.8 TPH

Treated juice % cane

:

105 %

Sp. Heat of juice

:

0.91

Exhaust temperature

:

1240C

Latent Heat of 1240C

:

522.4

Temperature 114 104 97 56

Latent Heat kcal/kg 529 536.2 542 566

R.J. 1st heating by Q5 vapour

=

C.J.Qty.x Sp.heat of juice x T Latent heat

R.J. 1st heating by Q5 vapour

=

244.8 x 0.91 x (42 − 32) = 3.9𝑇/ℎ𝑟 566

R.J. 2nd heating by Q2 condensate

=

C.J.Qty.x Sp.heat of juice x T Latent heat

R.J. 2nd heating by Q2 condensate

=

244.8 x 0.91 x (65−42) = 9𝑇/ℎ𝑟 566

R.J. 3rd heating by Q3 vapour

=

C.J.Qty.x Sp.heat of juice x T Latent heat

60 | P A G E

244.8 x 0.91 x (75−60) = 6.17𝑇/ℎ𝑟 542

R.J. 3rd heating by Q3 vapour

=

T.J. 1st heating by Q2 vapour

=

T.J.Qty.x Sp.heat of juice x T Latent heat

T.J. 1st heating by Q2 vapour

=

252 x 0.91 x (85−70) = 6.41𝑇/ℎ𝑟 536

T.J. 2nd heating by Q1 vapour

=

C.J.Qty.x Sp.heat of juice x T Latent heat

T.J. 2nd heating by Q1 vapour

=

Cl.J. heating by Q1 vapour

=

Cl. J. heating by Q1 vapour

=

252 x 0.91 x (103−85) = 7.8𝑇/ℎ𝑟 529 C.J.Qty.x Sp.heat of juice x T Latent heat

252 x 0.91 x (103−112) = 3.9𝑇/ℎ𝑟 529

For PAN A Massecuite -: 29% cane B Massecuite-: 11% cane C Massecuite-: 8% cane For A Massecuite

Vapour /Steam requiments

=

Pan Factor x(A Mc Brix – A Heavy Brics)x 𝑀/𝑐 A massecuite (Brics)

Consider Pan Factor For Continuos Pan -1.2 For Batch Pan – 1.5

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Vapour /Steam requiments

=

1.5 x(91.65 – 80.44)x 67.2 91.65

= 12.33𝑇/ℎ𝑟

For B Massecuite Vapour /Steam requiments

=

1.2x(92.6 – 82.83)x 26.4 92.6

= 3.34𝑇/ℎ𝑟

For C Massecuite Vapour /Steam requiments

=

1.2 x(97.8 – 78.82)x 19.2 97.8

= 4.47𝑇/ℎ𝑟

Steam consumption for Sulphur Burner

= 2 TPH

Steam Consumption for Dearator for 89 TPH Boiler

= 3 TPH

Steam condensed in the condenser of the turbine

=12

For Centrifugal station

=2%+2% losses=9.6 TPH

Total Steam Consumption

= 83 TPH

Stem% cane

= 34.9 % from calculation

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CO-GEN HOUSE

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Co-gen House This factory has a water tube boilers which having 94 Tons/hr of capacity for each boiler with 65 bar pressure and 520◦c. The steam generated by the boiler is used to generate electrical power and operate the mil. Exhaust steam from those turbines is used to heating purposes in process house.

Water tube boiler Water tube boiler has two main drums, lower drum and upper drum. These are connected with bent tubes. In addition to that, headers have been installed at the bottom of brick walls to collect hot water of the down comers from the upper drum. These down comers are on the brick walls facing one side to hot gasses, hence they covers the walls and reduces heat losses through the walls by absorbing heat on the wall. Headers have been connected to the lower drum from which generating tubes go to the lower side of the upper drum facing whole tube surface to hot gasses. In this generation tube, water becomes steam. The lower portion of steam drum, to which generating tube is connected, is covering with a baffle plate so that steam coming out will not affect the neutral water level of the drum. Initially the steam, from steam water saturated mixture passes through buffles. At the buffles the water droplets contained in the steam will be removed. When the steam hits on buffles the water droplets will condense and fall into the water. Steam then goes up along the baffle plate and passes through a set of inclined baffles, which separate steam with higher momentum. Then steam goes to the steam separator where water droplet is separated and condensate is sent down through the condensate pipe. Separated steam then passes through the super heating tubes to produce superheated steam. To make a steam flow from the steam drum to the superheated steam drum, pressures of the two drums are kept at 60 bar and 65 bar respectively.

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DESIGN SPECIFICATION Steam pressure maximum Working pressure Steam temperature Feed water temperature Feed water rate Actual steam evaporation Heating surface

= 66 kg/cm2 g = 66 kg/cm2 g = 510 ± 5˚C = 105˚C = 255ton/hr = 255 tones/hr = 5245 m2

Maximum cane crushed per day is 5250 tons. This will approximately produce 1425 tons of bagasse. Average moisture content is 49% and current boiler performance is taken as 72%. The main feature of boiler is that it consists of a 100% bagasse load and a 100% coal load. When the bagasse load becomes low, coal is also used as a mix to get the desired steam rate.

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FURNACE (COMBUSTION CHAMBER) This boiler is a dual fuel boiler. Bagasse is used as main fuel. But in some special causes such as moisture content of bagasse is too much (>54) or the bagasse will not enough for fire the boiler, furnace oil can be used. Combustion chamber has steam vaporizer tubes. It is built with bricks between tubes, so that there is no chance of tubes becoming dislocated or melting. The outer surfaces of the entire boiler is constructed with fire – bricks and adiabatic bricks to withstand high gas temperatures. The entire welded casing keeps aired tight, and prevents cooling air from entering into the casing. The outer surfaces of the bricks are further converted with heat insulation panels, and fully incased with total welds. Thus the boiler guarantees airtightness and protection from leakage of cool outer air. The combustion gas goes up the combustion chamber, turns a u – turn through the vent cut at the top part of the separating panel, passes through the steam tubes at a moderate speed, runs through the smoke duct, and finally leaves of the chimney. BOILER DRUMS

Water tube boiler has two drums. It is used for water & steam circulation. 1. Upper drum 2. Lower drum Upper Drum This is the upper drum of water tube boiler. Where steam is collected from the boiling water. The steam drum contains various features to ensure that water is removed from the steam. Feed water supply present in the upper drum only. But any special cause such as boiler drum level will too low, there is a small by pass feed water supply to the lower drum to prevent damage to the drum. The water is feed to this drum from the deaerator tank. This is connected to other lower drum and headers by number of tubes. The water level is kept in a constant height by the feed water system. The water level is maintained by feed water pump.

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Lower Drum Lower drum is contain water, the upper drum and lower drum are connected by a series of tubes, water circulation occurs between top and bottom drum. When the water is heated, Steam circulation occurs from bottom drum to top drum. Boiler Headers Headers are tubes, having larger diameter than water tubes. There are several headers inside the combustion chamber. They are; 1. Front header 2. Rear header 3. Two side headers 4. Super heater header BOILER TUBES There are used many types of boiler tubes present in the boiler according to their applications. 1. Down comers - These tubes are connected between upper drum and lower drum, that the boiler feed water comes from upper drum to the lower drum through these tubes. Totally 84 tubes are connected in two raw. 2. Generating tubes - Saturated steam generated in the lower drum going through these tubes to the upper drum. Totally 953 tubes are connected.

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3. Up rises – This is used for increasing rate of generating steam. These tubes connected between side headers, front header, rear header and the upper drum Generated steam in the above headers goes to the upper drum via these tubes. 4. Super heater tubes - Dry saturated steam separated from the upper drum is super-heated and goes to the super heater header via these tubes. Totally 24 tubes are connected.

FORCED DRAUGHT FAN (FD FAN) The Forced Draft fan (FD) is used in the boiler to supply natural air for increase the burning rate of fuel. The air from the fan goes to the combustion chamber. Capacity = 22 m3/sec Power = 75 kw Brake power = 100kw Speed = 1440 rpm Air temperature = 36 ◦c

INDUCED DRAUGHT FAN (ID FAN) ID fan is used to remove burned air from the boiler. ID fan is operated when the bagasse fired at a higher level, otherwise extinguish quickly. Before start the ID fan, exhaust gas by pass to the chimney without passing through air pre heater. Capacity = 45 m3/sec Power = 220kw Brake power = 100kw Speed = 990rpm Gas temperature = 150◦c

AIR PREHEATER For done the combustion process easily and with better efficiency, the air is heated before entering the combustion chamber. The flue gas, which is coming out (4th pass) from the boiler is used to heat the air. In the air preheated, the flue gas is gone through pipes to out from the boiler and the air is gone among the pipes to the combustion chamber. There are two fans for removing flue gas and to supply fresh air to combustion chamber. I.D fan is used to supply air and F.D fan for removing flue gasses. Those fans are help to control combustion and increase boiler efficiency by about 10%. Heating surface = 3455 m2 Inlet temperature = 36◦c Outlet temperature = 165◦c

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CHIMNEY The combustion gases (flue gases) are disposed into the atmosphere through the chimney, it also can be used to assist with the draught in the furnace. The ash fling is controlled by spraying water to the exhaust gas.

Boiler Feed Water Treatment The water should be treated before feed to boiler because of normal water may cause to corrode boiler tubes. Condensate water is used as feed water. First O2, CO2 and N2 gases are removed in deaerator, then add N2H4 (hydrazine) for further remove O2 and N2, Ph value of feed water is kept as 11 for reduce corrosion. Caustic soda is added to decreased acidity. DE-AERATOR

De-aerator is used to remove oxygen from feed water for prevent the corrosion of boiler tubes. PLSI uses spray type De-aerator. Here, there are no chemicals added and pure mechanically removed gasses. Here water spray from the top and steam supplied to the bottom. Because of that gasses are heated and remove from the top. Since steam is added here, the temperature of the feed water will increase it also will increase boiler efficiency. Deaerator water quantity = 100,000kg/hr Outlet temperature = 103◦c Feed water quantity = 97290 kg/hr

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The de-aerator water input is the condensate of 1st evaporators and the heater and it has by pass from the water storage tank. The capacity of this is 130m3/h and the input and output temperatures are 95˚C and 105˚ C FEED WATER PUMP The boiler feed water pump is a multi-stage centrifugal pump which having 65 bar delivery pressure. Since the upper drum of the boiler is having about 65 bar pressure, this type of pump being used. There are two main feed water pumps present. One is driven by an electric motor and another is by a steam turbine. At the beginning steam is not present and electric motor driven pump should be operated. SOOT BLOWERS This direct high-pressure steam from the boiler to the outside of the boiler tubes for removal of Soot. It will increase the rate of steam generation. BLOW DOWN Blowing down is done to maintain the dissolved and suspended solids within the rated value. Control of concentration is obtained by two methods, both involving draining off some of the concentrated boiler water. 1. Periodic manual blow off. Specially employed in smaller plants and where ppm of solids in feed water is low. 2. Continuous blow down, usually accompanied by heat-saving. STEAM DISTRIBUTION SYSTEM The super-heated steam is distributed through a common header. Then the low pressure steam from the turbine is collected to a common header and distributed to the process. Branch line connections, supports and hangings of this steam distribution system have been made correctly at required points.

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INSULATION In general, condition of the insulation of steam distribution system is good. But there are point in the lines where insulation is damaged and most of the fittings such as valves, flanges have not been insulated. 50

STEAM HEADER Steam header is the beginning point of steam distribution system. The size of steam header is depending up on the number of boilers, capacity of boiler and steam distribution system. Steam headers enables steam supply take from the main to high pressure users and pressure reduce applications. Following figure shows a steam header and its operation.

STREAM TRAPS It is very essential since it is the important link between good steam and condensate management. A steam trap retains steam within the process for maximum utilization of heat, but releases condensate and incondensable gases 71 | P A G E

at the appropriate time.The duty of a steam trap is to discharge condensate while not permitting the escape of live steam. This allows steam to reach its destination in dry a state to perform its task efficiently and economically. Steam traps can operate in a wide pressure range.

SAFETY VALVES This boiler is designed for a maximum working pressure of 65 bar.When pressure increased above that level it can be damaged. Safety valves are installed to avoid that. When pressure increased above 65 bar valves are opened automatically and release pressure. There are 2 safety valves for steam drum and one for super heater coil. The steam drum is set to pressure 67 bar and super-heated header is set 70 bar.Always steam drum set pressure is less than super-heated header pressure. If is negative when the pressure relief through the upper drum safety valve that time supper-heated coil is heated without steam in the coil.

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Steam Turbine The steam turbine has two rows of moving blades and one row of fixed blades. Steam enters the turbine through the combined stop and emergency valve and trough the control valves. Steam then passes via the nozzle ring to the first row of the moving blades. The fixed row of blades redirects the steam flow in to the second row of moving blades and then steam passes to exhaust. Normal speed of the turbine is 6915/1500 rpm and over speed trip set at 7500/1650 rpm. Turbine speed is control by governor. Data about Turbine Turbine model : Shin Nippon Mach. co. Ltd Rated steam flow : 85 000 kg/hr Inlet steam pressure : 66 kg/cm²g Inlet steam temperature : 500 ºC Exhaust steam pressure : .1 kg/cm² Max 1st Extraction pressure: 10.1 kg / cm2 Max 2nd Extraction pressure : 2.5 kg / cm2 Exhaust steam temperature at full load : 40 ºC Normal speed : 6915/1500 rpm Over speed trip set at +10% : 7500/1650 rpm Gears ratio : 1/ 4.129 Rotation of gear output shaft looking from turbine towards alternator: clockwise

Governor Steam turbine governing is the procedure of controlling the flow rate of steam into a steam turbine so as to maintain its speed of rotation as constant. The variation in load during the operation of a steam turbine can have a significant impact on its performance. In a practical situation the load frequently varies from the designed or economic load and thus there always exists a considerable deviation from the desired performance of the turbine. The primary objective in the steam turbine operation is to maintain a constant speed of rotation irrespective of the varying load. This can be achieved by 73 | P A G E

means of governing in a steam turbine. It has gerotor oil pump, accumulator, power piston, pilot valve system and ballhead.

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CO GEN CALCULATIONS Sensible heat of feed water (h) Total heat of superheated steam (H)

= 1200C = 774 KJ---For 65 Kg/cm2

1) Pol % Bagasse 2) Moisture % Bagasse 3) Bagasse % cane 4) Boiler Efficiency 5) Boiler Efficiency 6)Boiler Efficiency Therefore,

= = = = = =

1.5% 49 % 27 % 61 % ---For 21 Kg/cm2 64 % ---For 45 Kg/cm2 61%--- For 14 Kg/cm2

GCV

= 4600 - 12S - 46 x W = 4600 – 12 x 1.5 – 46 x 50 = 2344 Kcal/kg

NCV

= 4250 - 12S – 48.5 x W = 4250 – 12 x 1.5 – 48.5 x 50 = 1859 Kcal/kg

H SOURCE OF LOSS DRY GAS LOSS(4.96%) MOISTURE LOSS(22%) UNBURNT LOSS(2) RADIATION LOSS(.37%) UNACCOUNTED LOSS(0.4) TOTAL LOSS G.C.V-Losses Steam Fuel Ratio

=1647Kcal/Kg 𝐺.𝐶.𝑉−𝐿𝑜𝑠𝑠𝑒𝑠 = =

Efficiency

LOSS 116 516 46.88 8.67 9.38 697Kcal/Kg

=

𝐸𝑛𝑡ℎ𝑎𝑙𝑝𝑦 𝑜𝑓 𝑠𝑡𝑒𝑎𝑚 1647 774

= 2.12

𝐺.𝐶.𝑉−𝐿𝑜𝑠𝑠𝑒𝑠 𝐺.𝐶.𝑉

=70.2% 75 | P A G E

FORM R.T 8C

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Conclusion The maintenance period of the factory is very useful to mechanical engineering trainee if trainee has enough training period. Because all machines and equipments are completely dismantling, repairing and installed again for the new crushing season. We can collect lot of mechanical engineering knowledge in the maintenance period than production season. Pelwatte Lanka Sugar factory has Boiler, Mill, Power house, Process house and Factory workshop. So that covers more of mechanical engineering field. This place is very good for mechanical engineering undergraduate trainees. Large scale agriculture, Engineering, Operation, Human Resources Management and Financial handling are available in the company. Number of workshops and labs that help for the production are also available. An Undergraduate trainee can covers a vast practical aspects in the company including Mechanical Engineering, Electrical Engineering, Chemical Engineering and Agriculture engineering. Large land preparation, Harvesting and Loading equipments and machines can be seen here. Agriculture work shop is an ideal place for an Automobile engineering student. Dismantling and assembling of various kinds of vehicle engines are frequently happening. In the factory workshop every kind of essential workshop equipments such as lath machines, shapers, drills, presses, cutting tools, and welding plants is available. There is a generators which produce 15 MW in the power house. In addition there are 4 huge diesel generators sum of approximately 2720KVA are available for sudden power fallers. In industry most of workers does not have theoretical knowledge but they have more technical experience. Always as a practice I asked questions when they were working in shops and they explained me deeply. Finally I could get maximum benefit out of this training. It will help to my future career activities. Sometimes I worked at shops I did not disturb on going works of the shops. Perhaps I helped them by instructing and guiding them how to work. In addition to those things by speaking to engineers, formants I caught lot of managerial aspects and experiences how human resources are handled. According to my feeling E.I.D Parry is ideal place for mechanical engineering trainees.

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