Usman Report

Shakarganj Historical Background Shakarganj’s history dates back to 1967. The company was incorporated on 20 September 1967 with the object of setting up a sugar mill in district Jhang in the central Punjab. Commencement of business certificates was issued on 23 February 1970. A mill with a design capacity of 1500 TCD extendable to 2000 TCD was planed and ordered for supply of equipment was placed with Messrs. Stork-Werkspoor sugar B.V., of Netherlands. Letter of credit was opened on 31 December 1969 and 10 January 1970. Construction of building started in March 1971. The implementation of the project got delayed due to war in 1971 resulting in breakup of the country. Some shipment of machinery was delayed. Insulation of equipment stated on 1st January 1972 and project commenced trial operation on 7 January 1974. Public offer of shares was made on 21 may, 1979. Even since the team at shakarganj has never looked back. The sugar factory has been expanded to a capacity of 10000 TCD extendable to 14000 TCD and has become the largest sugar factory in the country. Shakarganj realized the need for research and setup shakarganj sugar research institute in 1983. This was to strengthen research activities in sugar cane agriculture, sugar manufacturing and engineering. Shakarganj has diversified into utilization of co-products, with the addition of a distillery in 1986 and particleboard plant in 1991.shakarganj took a major step in co-generation of electricity for sale to the national grid in 1983. Balancing and modernization of sugar plant was carried out between 1976 and 1980 and plant capacity was upgraded to 2000 TCD. By 1986 the capacity was increased to 5000 TCD(total cane / day). The team at shakarganj recognized technological advancements and kept constantly in step with the latest innovation and development in sugar industry. A modern distillery based on Biostill technology was addedin 1986. The distillery unit went into production on 20 september,1986 with an installed capacity of 45000 liters of industrial alcohol per day. In 1990 a particle board plant with a daily production capacity of 30 cubic meter was added to convert surplus bagasse into value added products. In 1991 work initiated on doubling the capacity of the plant with the provision to further extend the capacity to 14000 TCD. Entire designing and engineering work was done in house by the shakarganj team. The program was completed in 1992. It pushed the mill capacity to 10000 TCD extendable to 14000 TCD. This made shakarganj, Pakistan’s largest sugar mill. Shakarganj took a major step in co-generation of electricity for sale to national grid. Agreement with Water and Power Development Authority (WAPDA) was signed on 25 July 1993 at Lahore making shakarganj the first private sector power supplier in Pakistan. Shakarganj took care of 12.86 percent of Jhang City’s power requirement during crushing season. Since 1995, 2 MW electricity is being supplied to a neighboring textile company.

Shakarganj Research Institute:: Shakarganj research institute (SSRI) was set up in 1983to strengthen research activities in sugarcane Agriculture, sugar manufacturing and engineering. In first phase,

Internship Report activities in sugarcane agriculture were stared, which resolved around selecting new sugarcane varieties and providing guidance to sugarcane growers about agronomic, pathological and entomological problems of crop. This is the only institute of its kind in Pakistan. Facilities at the institute include laborites for Breeding, Agronomy, Soil Science, Plant Pathology and Biological control of Borers. In 1983 experiments were started on 10 hectors of land in vicinity of institute. The institute has 600 hectares of land at its disposal. Sugarcane is planted on 500 hectares for research experiments. By the year 1988 two verities, SPSG-26 and SPSG-394 were selected. Both were early maturing and sugar contents was higher than BL-4 (present commercial variety). On completion of agronomic and pathological tests these verities were released to farmers. Area under these varieties is gradually increasing. Two new varieties, SPSG-224 andSPSG-79 have been added to the list recently. Biological control of Pyrilla was stated in 1991. Control of borer complex was stated from 1995. During 1996, 4500 hectares of sugar cane crop was covered through biological control. The institute also organizes workshops and invites world-renowned sugar experts for interaction with Pakistani experts. Shakarganj Sugar Research Institute was selected by international society of sugarcane technologists to host the first ISSCT workshop in Pakistan on Engineering and Energy workshop on factory design from 23 February to 28 February, 1997.

Environmental Awareness: • • • •

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Shakarganj is clear about its responsibilities to the environment and is very active in conservation. We are constantly making efforts to reduce waste and recycle process chemicals. Our environmental policy evolves around three basic principles: Shakarganj assumes responsibility for environment Decision shall favor environment Information shell be open and free. Shakarganj takes active part in tree plantation with the community. To set an example 40000 trees have been planted around the sugar factory. The same piece of land had only one tree in 1974. Recycling of sugarcane nutrient to the field is done by mixing filter cake with distillery stillage.

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Cane is Brought from cane yard to Sugar Factories on the Trucks and Tralers .Cane weighing is take place with the help of Three Weigh Bridges. These Weigh Bridges are Avery England Design .02 Weigh Bridges are for Gross Weight and 01 Weigh Bridges is for Tare Weight..Capacity of the Weigh Bridges is 50 Tons. .

Cane Unloading: Cane Unloading is done with the help of Electric Hoists. Three Electric Hoist are attached to Mill Tandem .The Function of these Electric Hoists is to Lift the Cane loaded Truck and throw it to Dumping Carrier.

Electric Hoist: Motor Steel wire rope Rope Diameter Gear Lifting Speed Lifting Height

Brake Type 7/8 inch Reduction gear 13-20 ft/ min 20 m

Dumping Carrier: There are three dumping carrier in each mill tandom. In Which sliding plates are attached which carry the cane to the Main Carrier. Idler Pulleys are used to support the chain on which sliding plates move. These idler pulleys are coated with some material so that to stop wear and friction. V-Belt drive used to transmit power from motor driven shaft to gear system and from there with the chain sprocket mechanism it drives the Dumping. Dumping Carrier Length 42 ft Dumping Carrier Width 17 ft Dumping Carrier Angle 18deg Linear Speed 24 ft/ min Gear Ratio 1/80

Sliding Plates: Length Width Roller Chain pitch

6.5 feet 8-9 inches 9 inches

Chain Sprocket Mechanism: When high torque load is to be transmitted. We use chain sprocket mechanism. By the Formula of power as torque is very high and speed is low then slippage takes place. So belt could not be used there and chain sprocket mechanism is the better choice.

Mill Tandem NO. 02: Mill Size Dia of Mill Roller Shell Length of Mill Roller Shell

38*78 inches 38 inches 78 inches

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7500 TCD (Tons crushes per day)

Main Carrier: Purpose of feeding. Length Straight length Elevated portion Width Before Shredder Width After shredder Width Angle Before Leveler Angle after leveler Linear Speed Motor Speed Motor Power

giving an angle to the main carrier is evenly distributed and compact 150 ft 100 ft 50 ft 90 inch 90 inch 78 inch 09 deg 12 deg 30feet/ mint 980 rpm 100 hp

Leveler : As the name implies it function is to provide evenly feed to cutters. Leveler arms 38 Leveler angle 6-7 degree Leveler Speed 36 rpm Supply source motor driven Motor speed 980 rpm Motor Power 100 hp Bush coupling

Cutter #01: Cutters are driven by backpressure Impulse Turbine. Bush coupling is uses to join the driver shaft to the driven shaft. No. of knives 70 Hard face cutter Cutter speed 600 rpm Turbine Power 1200kw Live Steam Pressure 23-24 kg/cm2 Temperature 325-350c Exhaust Steam Pressure 01 kg/cm2 Turbine Speed 1500 rpm

Cutter # 02 : This cutter also uses Backpressure Impulse Turbine for its Operation . Bush Type coupling is used . Reduction gears are used to reduce the Turbine speed . Live steam pressure and Exhaust steam pressure and temperature remain the same for all Backpressure Impulse Turbines No. of knives 70 Turbine Power 750 kW Turbine Speed 1500 rpm Cutter Speed 600 rpm

Cutter # 03 : This cutter is driven by Electric Motor.

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52 600 rpm 600 kw

Cane Shredder : The main function of the shredder is to rapture the structure in order to open the cells of the cane .It is driven by Backpressure Impulse Turbine.This Shredder is covered by anvil plate .It is below the Shredder. It has very low spacing in mm with hammers . Shredder has Stainless steel hammers with beadings . Shredder gets feed from below and takes it above .that is why its anvil plate is below .Its BMA Design Germany. Shredder Holders 57 No. of Bars 08 No.of Hammers 228 Weight of hammer 15.5 kg Turbine speed 1000-1100 rpm Turbine power 2000 kW

Magnetic Iron Separator: It’s ANDRIN France Design. Power

17.7 kW

Mill Tandem NO. 02 : No. Of Mills 04 It’s Walker Design Australia. All the four Mill units have same arrangements same number of Mills.Trash plate is used to clean the mill rollers . Mill top roller has tail box coupling with the driving shaft of the Turbine and it drives Mill feed roller and Mill discharge roller. These Mill units are turbine driven and input live steam pressure , exhaust pressure and temperature conditions remains same for all the Turbines. Separate Tail box drive for Mill roller and Pressure Feed Roller.

Mill # 01 : There are 6 rollers (1) - Pressure Top Roller. (2) - Pressure Bottom Roller. (3) – Underfeed Roller. 03 Mill rollers. (1) –Mill Feed Roller. (2) –Mill Discharge Roller. (3) –Mill Top Roller. Turbine power 850 kW Speed 1000-1100 rpm Live Steam Pressure 23-24 kg / cm2 Exhaust pressure 01 kg / cm2 Temperature 325-350c

Mill #02 : Mill unit #2 has same arrangement same type of turbine as mill #01.

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Mill#03 : Mill unit has same arrangement as above. Turbine power 750 kW Maximum Speed 2200 rpm Driven Speed 1000-1100 rpm Temperature 325-350 c

Mill # 04 : Mill unit has same arrangement as above. Turbine power 1044 kW

Reverse Pressure Gear/ Back Gear : This gear rotates the turbine in reverse direction slowly as in case when some obstacle comes in the mill roller to release it. It is driven by electric Motor.

Rotary Juice Screen : Unscreened juice comes from storage tanks here it passes through rotary screener and screened juice is sent to the process house.

Mill Tandom # 01 Mill size Dia of Mill Roller shell Length of mill roller shell Crushing Capacity No of Mills

36 *72 inches 36 inches 72 inches 5500 TCD ( tons crushed per day ) 05

Dumping Carrier : It has 03 rows. Sliding plates are attached Length 60 feet Width 17 inches Linear Speed 24 feet/ mint Sliding Plate Length 5.5 feet Sliding Plate Width 8-9 inches Carrier Angle 18 degree Roller chain pitch 06 inches Gear ratio 1/80

Leveler # 01 : Chain Procketer Mechanism is used. No. Of arms 26 Speed 39 rpm Motor power 100 kW 6

Leveler # 02 : Speed No of arms

39 rpm 24

Pusher Drum : The function of the pusher drum is to push the compact sugar cane to the Fabiriser. Reduction Gear are applied. Speed Ratio 22.4 Reduce Ratio 2.7 Dia of Drum 2250 mm

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Internship Report Length of the Drum Motor power

7200 mm 1000 Kw

Fabirizer: Fabirizer does the same function in Tandom #1 as Shredder in Tandom #2.In Fabirizer it takes input feed from the top and pushes it to the bottom. It has anvil plate on the top. Then it has feed rake bar and rake bar under carrier. It is Turbine Driven. Power 3 Mw Speed 1000 rpm No of holders 36 Stainless steel Bars 08 Hammers 108 Coupling type spring

Mill Tandem # 01 : No of Mills 05 Mill No 01 : It’s Walker Design Australia. Separate Tail Bar drives for Mill Roller AND pressure Feed Roller. 02 Tail Bar are used. 06 Roller mill 03 Pressure Feed Roller (1) - Pressure Feed Bottom Roller. (2) - Pressure Feed Top Roller. (3) - Under feed Roller. 03 Mill Rollers. (1) - Mill Top Roller. (2) - Mill Feed Roller. (4) – Mill Discharge Rsssssoller. Mill Rollers are Turbine driven. Turbine power 850 Kw Live Steam Pressure 23-24 kg/ cm2 Exhaust steam Pressure 01 kg/ cm2 Temperature 325-350 c Turbine Speed 1800 rpm Mill Roller Speed 5-6 rpm

Mill # 02 : Last Four Mills of Tandom # 01 are works poor Design. It is 05 Mill Tandom. Single Tail Box coupling is used to rotate both mill roller and pressure Feed Roller. Pressure Feed Roller is connected to Mill Roller with chain drive. Here slow Speed Gear is used instead of Bull Gear. Feed rake Bar is driven by Electric Motor. 02 Pressure Feed Roller. (1) – Pressure Feed Top Roller. (2) – Pressure Feed Bottom Roller. 03 Mill Rollers. (1) – Mill Top Roller. (2) – Mill Feed Roller. (3) – Mill Discharge Roller. Turbine power 600 Kw

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Mill # 04: Same arrangement as Mill #03. Turbine Power 750 Kw

Mill # 05 : Same arrangement as Mill # 04. Turbine Power 597 Kw Gear Ratio 1/52 Mill Roller Speed 5-6 rpm Turbine Speed 1800 rpm

Rotary Juice Screen ; Same as in Tandom #02.

Types of Bearing ; •

Roller Bearing.

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General Bearing.

As the name implies this type is Roller contact bearing. These are used for high strength and have a good alignment. These are used for low torque and high speed. These are sliding contact bearing and used for high torque and slow speeds.

Types of couplings: •

Bush Coupling.

It has sliding contact. It don’t need lubrication .it is self-lubricant. Used where distances are minimum. It is used for power transmission.

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Tail Box coupling. It is used for larger distances. These are shock absorber. Used for high load transmission. .

Mill House Output: Screened cane juice and bagass is the output of the mill house.

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There are several important aspects to extraction which involve the energy balance of the factory, the efficiency of extraction and therefore ultimately the profitability of operations: The manager needs to process the cane as soon as possible if sugar losses are to be avoided yet needs to have a sufficient supply in storage for times when cutting and transport are stopped, whether deliberately or not. Typically, cane is processed within 24 hours of cutting; Cane preparation is critical to good sugar extraction, particularly with diffusion extraction. This is achieved with rotating knives and sometimes hammer mills called "shredders". However shredding requires extra energy and more equipment; The extraction is actually conducted as a counter-current process using fresh hot water at one end being pumped in the opposite direction to the cane. The more water that is used, the more sugar is extracted but the more dilute the mixed juice is and hence the more energy that is required to evaporate the juice; The more accurately that the mills are set [adjusted], the drier is the residual fiber and hence the less sugar remaining in the fibre; A typical mixed juice from extraction will contain perhaps 15% sugar and the residual fiber, called bagass, will contain 1 to 2% sugar, about 50% moisture and some of the sand and grit from the field as "ash". A typical cane might contain 12 to 14% fibre which, at 50% moisture content gives about 25 to 30 tons of bagass per 100 tons of cane or 10 tons of sugar.

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What is Boiler: A boiler is a closed vessel in which water or other fluid is heated.

Types of Boilers : • Water Tube Boiler: In water tube Boiler a number of water tubes are arranged in and around the furnace.Water circulates in the tubes and outside is the fire. This type generally gives high steam production rates, but less storage capacity. water tube boilers are also capable of high efficiencies and can generate saturated or superheated steam. The ability of water tube boilers to generate superheated steam makes these boilers particularly attractive in applications that require dry, highpressure, high-energy steam, including steam turbine power generation.

•

Fire Tube Bioler:

In fire Tube Boiler There is a fire in the tubes and water is present outside the tubes in the big vessel or cylinderical drum. Fire-tube boilers usually have a comparatively low rate of steam production, but high steam storage capacity.

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Boiler # 01 : Make Fuel Capacity Heating Surface Working Pressure Steam Temperature Bagass Pole Moisture in Bagass

Stork Babcock and Wilcox. Bagass / Sui gas / biogas. 40 Tons / hr 1348 m2 23-24 kg/ g.cm2 325-350 C 1.5 50%

Boiler # 02 : Make Fuel Capacity Heating Surface Working Pressure Temperature

FCB France Bagass / Sui gas / biogas. 80 Tons / hr 2071 m2 23-24 kg / cm2 350c

Boiler # 03 and 04 : Make Fuel Capacity Heating Surface Working Pressure Steam Temperature

Yushmine Japan / Itefaq Brothers. Bagass / Sui gas / Biogas. 80 Tons / hr. 2220 m2 23-24 kg/ cm2 350 c

Main Bagass Carrier # 01 : Length 94 m Width 02 m Linear Speed 26 Feet/ mint Bagass elevator from Tandom # 01 in boiler #01.

Main Bagass Carrier # 02 : Length 50 m Width 02 m Linear Speed 30 Feet / mint Bagass elevator from Tandom #02 in Boiler #02. Return Bagass Carrier is attached to Boiler # 04. Surplus Bagass Carrier is attached to Boiler #05.

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Internship Report Three condensate storage tanks. One is large size have a capacity of 565m3 and two are small size have a capacity of 230 m3.

Dearation Station : This station has also three storage tanks. Two have a capacity of 22 Tons and one has a capacity of 33 Tons storage availability. Then there is reserve storage tank.

Feed Water Station : In feed water station there are 08-turbo pumps.04 are small size. Power 225 hp Speed 2980 rpm Capacity 96 Tons Pressure 35-kg/ cm2 Temperature 110 c 02 pumps are medium size. Power 215 hp Speed 2900 rpm Capacity 100 Tons Pressure 30 -kg/cm2 Temperature 110 c 02 are large size pumps. Power 300 hp Speed 2900 rpm Capacity 188 Tons

Make up Water Station : Total pumps in this station are 04 in number. 02 are 40hp and 02 are 30 hp power capacity. Pump Speed 1470 rpm Capacity 60 m3 / hr

Live Steam Header : This live steam header is used to store the steam. Header Dia 1524 mm Length 6705 mm

Boiler Fans:

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ID Fan (Induced Draught Fan):

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FD Fan (Forced Draught Fan):

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SD Fan (Secondary Fan):

Induced draught fan draw gases out of the boiler. The gas has already passed through the air heaters and precipitators before it has reached these fans.

Each unit has forced draught fan. The fan draws warm air from the top of the boiler house through large air heaters becoming the primary and secondary air used for the boiler combustion process. The air heater warms the incoming air by transferring heat energy from the outgoing flue gases. Secondary Fan is also admitted turbulently to complete the combustion. This fan supplies air to the furnace from the bottom surface to ensure complete combustion.

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Internship Report A furnace is a device used for heating

Super heater : A superheater is a device in a boiler that heats the steam generated by the boiler again, increasing its thermal energy and decreasing the likelihood that it will condense inside the header. Superheaters increase the efficiency of the boiler, and were widely adopted. Steam which has been superheated is logically known as super heated steam.

Air Pre-heater : This air pre-heater is used to heat the air inducted to the boiler by the hot flue gases. Thus raising the temperature of inlet air up to 110 C.

Economizer: Flue gases from large boilers are typically 450 - 650°F.Economizers recover some of this heat for pre-heating water. The water is most often used for boiler make-up water or some other need that coincides with boiler operation. Economizers should be considered as an efficiency measure when large amounts of make-up water are used.

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Origin of the Problem andits Treatment:

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Scaling:

Total hardness in the water if not properly removed will cause in scale formation. A layer of scale on the metal surface of the boiler will acts as an insulator and reduce the rate of heat transfer from hot zone to water. A layer of scale as thick as the surface of the boiler will reduce boiler efficiency by some 20%. Scaling results in  More fuel will be used to maintain boiler output at acceptable level.

 Since heat transfer is retarded the metal become hotter to a point where it deforms and even rapture with disastrous results.

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Corrosion:

The most common source of corrosion in boiler systems is dissolved gas: oxygen, carbon dioxide and ammonia. Of these, oxygen is the most aggressive. The importance of eliminating oxygen as a source of pitting and iron deposition cannot be over-emphasized. Even small concentrations of this gas can cause serious corrosion problems.

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Caustic embrittlement /Pitting:

The destructive action of highly concentrated caustic water on metal below the water line is called pitting or caustic embrittlement . It is actually formed if any basic impurity is being added water . It will form hydroxyl ions which when reach the periphery react with iron and form ironhydroxide. Thus it produces holes in boiler.It can be prevented as:

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Slight treatment with acid before water is taken into the boiler. The pH of boiler should be checked thereby we can only know that pitting is going on.

 By the addition of sodium based phosphates like Na H PO ,NaH PO etc . • Sludge formation: 2

4

2

4

The impurities which are floating on the surface in the form of light fluffy mass are called sludge’s .These are insoluble impurities that float at the surface of water at high temperature. Treatment is as follows: The impurities of Na , Ca , Mg ,react with ant scaling agent and form their sulphates and phosphates which are easily removed. However due to sludge formation the rate of water evaporation is decreased .The sludge formation starts at 40oc and maximum sludge is produced at 80oc, at this temperature it is automatically drained off .

Key Factors For Boiler Efficiency Calculations: • • • • • •

Flue gas temperature (Stack temperature) Fuel specification Excess air Ambient air temperature Radiation and convection losses. Flue Gas Temperature

High boiler efficiency is the result of specific design criteria, including

• • • • • • • • • • •

Number of boiler passes Burner / boiler compatibility Repeatable air/fuel control Heating surface Pressure vessel design Boiler efficiency calculations that are accurate and representative of actual boiler fuel usage require the use of proven and verified data, including: Proven stack temperature Accurate fuel specification Actual operating excess air levels Proper ambient air temperature Proper radiation & convection losses

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A Demineralisation Plant consists of two pressure vessels containing cation and anion exchange resins. Various types of ion exchange resins can be used for both the cation and the anion process, depending on the type of impurities in the water and what the final water is used for. Typically, the cation resin operates in the hydrogen cycle. The cat ions in the water (i.e. calcium, magnesium and sodium) pass through the cation exchange resin where they are chemically exchanged for hydrogen ions. The water then passes through the anion exchange resin where the anions (i.e. chloride, sulphate, nitrate and bicarbonate) are chemically exchanged for hydroxide ions. The final water from this process consists essentially of hydrogen ions and hydroxide ions, which is the chemical composition of pure water. Simple demineralisation plant consist of Composite resin vessels with charge of strong cation and anion resin; control-panel encompassing a conductivity measurement and alarms, etc; acid and caustic injection facility from bulk, semi-bulk or carboy containers.

RO Plant : Reverse osmosis plants have at their heart a membrane that if damaged reduces output, increases costs and gives poor water quality so it is important to keep it clean and operating efficiently. Most reverse osmosis membranes are formed from hollow fibre or thin film composite sheets with the membrane allowing passage of pure water and rejecting the dissolved solids contained in the water. As water passes along the membrane surface the solids concentration increases and some sparingly soluble salts start to exceed their solubility and precipitate. When precipitated onto the membrane surface this causes fouling that may reduce output and increase product water conductivity. The worst of these solids being calcium carbonate and calcium sulphate and so the prevention of their precipitation is vital if the membrane is to function efficiently.

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RO Membrane Antiscalant : Effective membrane Antiscalant should be;

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Safe to use and safe to handle.

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Good scale inhibitors.

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Membrane compatible.

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Effective across a wide range of ph.

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Compatible with other products.

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Cast effective.

Deaerator : Mechanical and chemical Dearation is an integral part of modern boiler water protection and control. Deaeration, coupled with other aspects of external treatment,

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Internship Report provides the best and highest quality feed water for boiler use. Simply speaking the purposes of deaeration are 1.

To remove oxygen, carbon dioxide and other non-condensable Gases from feed water.

2.

To heat the incoming makeup water and return condensate to an optimum temperature for: a.

Minimizing solubility of the undesirable gases

b.

Providing the highest temperature water for injection to the boiler

Reasons to deaerate : The most common source of corrosion in boiler is dissolved gas: oxygen, carbon dioxide and ammonia. Of these, oxygen is the most aggressive. The importance of eliminating oxygen as a source of pitting and iron deposition cannot be overemphasized. Even small concentrations of this gas can cause serious corrosion problems.

Operation: Mechanical deaeration is the first step in eliminating oxygen and other corrosive gases from the feed water. Free carbon dioxide is also removed by deaeration, while combined carbon dioxide is released with the steam in the boiler and subsequently dissolves in the condensate. This can cause additional corrosion problem.

Back Pressure Turbine # 01,02: • • • • •

Rated power Inlet temperature Rated Speed Inlet Pressure Outlet Pressure

06MW 325 C 3000 rpm 2.35 Mpa 0.245 Mpa

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Rated power Rated Voltage Rated Current Rated Speed Rated Frequency Rated Power Factor

6000 Kw 11000 Kv 393.6 A 3000 rpm 50 Hz 0.8

Turbine # 03: • • • •

Rated Power Rated Speed Gear Ratio Weight

2200 Kw 1500 / 5269 rpm 3.51 3000kg

3-Phase Generator: • • • •

Rated Voltage Rated Current Power Factor Speed

440 V 351 A 0.75 1500 rpm

Condensed Turbine # 04,05 : • • • • •

Rated Power Rated Temperature Rated Speed Inlet Pressure Exhaust Pressure

6 MW 350 C 3000 rpm 2.40 Mpa 0.392 Mpa

Generator • • • • • • •

Rated power Rated Voltage Rated Current Speed Frequency Phase Number Power Factor

06 MW 11000V 393.6 A 3000 rpm 50 HZ 03 0.8

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Back Pressure Turbine : First three Turbines in the powerhouse are backpressure Impulse Turbines. Backpressure means that the exhaust of these turbines is not also steam of pressure above than atmospheric pressure. Noncondensing or backpressure turbines are most widely used for process steam applications. The exhaust pressure is controlled by a regulating valve to suit the needs of the process steam pressure. These are commonly found at refineries, district heating units, pulp and paper plants, and desalination facilities where large amounts of low pressure process steam is available.

Advantages of Back pressure Turbines: 1234-

Process Heat For various Operating loads can be provided. Electrical power to meet the own and for Feeding into the Public grid is available. Balancing of operational Fluctuations between Power and steam requirement. Avoidance of exceeding the maximum Demand limits for power imported from the Public grid.

Condensed Turbines: Condensing turbines are most commonly found in electrical power plants. These turbines exhaust steam in a partially condensed state, typically of a quality near 90%, at a pressure well below atmospheric to a condenser.

Turbine Efficiency : To maximize turbine efficiency, the steam is expanded, generating work, in a number of stages. These stages are characterized by how the energy is extracted from them and are known as impulse or reaction turbines. Most modern steam turbines are a combination of the reaction

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Internship Report and impulse design. Typically, higher pressure sections are impulse type and lower pressure stages are reaction type.

Juice that is coming from milling house has following properties: • Acidic • Opaque • Greenish color

•

Brix (thickness) 10 – 15 • Soluble impurities Insoluble impurities like proteins, waxes, gums etc. Physical and chemical processes are required for the production of sugar. These operations carried out in process house. Main units in process house are:

Primary Heaters: Juice which is coming from Tandem 1 and Tandem 2 is pumped to primary heaters, there are six (6) primary heaters for tandem 1 and tandem 2, three (3) set for each tandem. Heaters used for heating juice coming from tandem 1 is called primary heaters set no.1 and that is used for heating juice of tandem 2 is called primary heater set no. 2. These are shell and tube heaters, heating is done by vapors coming from evaporators, juice moves in tube side and vapors in shell side, duplex valves are used for the transfer of juice in heaters. heating is done for proper reaction with lime in reaction tank. Specifications of heaters are given below: Outer diameter of each tube = 38 mm Thickness of tube walls =2.50 mm Inside diameter of each tube = 38 – 2.50 =35.5 mm Length of each tube = 4500 mm Total no. of tubes in each primary heater = 696 tubes No. of passes in each primary heater = 12 No. of tubes in each pass = 58 Juice heating temperature = 60-770C Heating surface = 3.1416*d*L* no.of tubes = 3.1416 * 35.5 * 4500 * 696 = 349301937.6 mm2 = 349.3019376 m2

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Defication: Defecation is process of removal of impurities by the action of lime and heating. Defication is carried out in following equipments.

Lime Dozer: Juice coming from primary heater set no. 1 and primary heater set no. 2 enters in lime dozer from top. Here we add lime {Ca (OH)2} to it. Lime is used to combine impurities that is present in juice because juice is acidic in nature and when lime is added which is basic in nature then PH is maintained at 7.8 to 8.2

Retention Tanks: In retention tanks juice enters from the bottom. The object of these tanks is to mix juice with lime and to give the reaction to lime and juice and reaction time is provided. There are four retention tanks in SML. In retention tanks plates are arranged in manner that one plate is below and other is above, this arrangement is done for proper mixing and mixing is done by agitation.

Defecation Tanks: There are two defecation tanks in SML. Juice coming from retention tanks enters in defecation tanks separatelyondary Heaters: Neutralized juice coming from defecation tank no.1 and defecation tank no.2 is heated in secondary heaters set no. 1 and secondary heaters set no.2 respectively. These are total eight (8) in numbers and four (4) for each set. Heating media in first three secondary heaters is vapors that is coming from evaporators and in forth one heating is done by exhaust stream (stream that is exhausted from turbine). Exhaust stream is used because we require high temperature to clarifier the juice and vapors can’t do this job. The specifications of secondary heaters are given below: Outer diameter of each tube = 38 mm Thickness of tube walls = 1.25 + 1.25 = 2.50 mm Inside diameter of each tube = 38 – 2.50 = 35.5 mm Length of each tube = 4500 mm Total no. of tubes in each primary heater = 468 tubes No. of passes in each primary heater = 12 No. of tubes in each pass = 39 Juice heating temperature = 100 - 1050C Heating surface = 3.1416*d*l*no.of tubes = 3.1416 * 35.5 * 4500 * 468 = 234875440.8 mm2 = 234.8754408 m2 = 2528.17 ft2

Flash Tank: Juice that is heated in secondary heaters set no.1 and secondary heater set no. 2 is now brought to flash tank with the help of duplex valves (to bypass the juice).Flash tank is simply a conical tank where juice is entered from the side of conical section. There are four(4) flash tanks one for each clarifier. The purpose of flash tank is to remove non condensable gases and air from juice. Now juice is transferred to next equipment from bottom of flash tank.

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Clarifiers: There are four (4) clarifiers. Clarifiers are used for the clarification of juice. Bagasse and mud are removed here.Poly electrolyte (poly acryl amide) solution is added in clarifier from coagulation tank (tank where solution is prepared) . The stock solution of polyelectrolyte is prepared in one tank and then diluted in two tanks. The dose of polyelectrolyte is in ppm. The stock solution of polyelectrolyte is prepared before 8-10 hours. There are two coagulation tanks in SML one is sufficient for two clarifiers. Overflow Juice from clarifier is collected in juice tank at the side of clarifier then it is passed through 80- mesh screen where particles present in juice are removed then it sent to clear juice tank. In sugar industry, clarifiers are the complicated and more sensitive point. These clarifiers are actually responsible to run an industry or shut down. It is the process where the juice is clarified.

Preheaters: Clear juice after screening goes to preheaters where juice is heated up to 1050C.There are two(2) prheaters in SML.Juice is preheated before evaporation. The specification of preheaters are given below: Outer diameter of each tube Thickness of tube walls

= 38 mm = 1.25 + 1.25 = 2.50 mm Inside diameter of each tube = 38 – 2.50 = 35.5 mm Length of each tube = 4500 mm Total no. of tubes in each primary heater = 564 tubes No. of passes in each primary heater = 12 No. of tubes in each pass = 47 Juice heating temperature = 100 - 1050C Heating surface = 3.1416*d*l*no.of tubes = 3.1416 * 35.5 * 4500 * 564 = 283055018.4 mm2 = 283.0550184 m2 = 3046.7781 ft2

Mud Level in Clarifiers: The mud level in the clarifiers is determined by dipping iron rod with thread. When it touches the mud, the length of the thread is measured and we came to know the level of the mud in clarifiers. Then the clear juice is passed through 60 to 80mesh plate into the clear tank. This juice must be clear. If juice is not clear, then it increases many problems: •

• •

Suspended and dissolved particles decrease brix in evaporators due to scale formation. More energy is required to get same level of brix of syrup. The sugar produced contains fibrous material as foreign matter.

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Mud Boot: Impurities which are settle down in clarifier are collected in tank known as mud boot placed at the bottom of the clarifier. There are four mud boots, one for each clarifier.

BD (begasse dust) Mixer: Mud from mud boot is pumped to BD mixer and baggasse from mill house is added with the help of conveyer. It is simply a vessel and baggasse is added just to increase pore size of mud so that we can easily separate juice from mud.

Vacuum Filter: Mixture of mud and baggasse is brought to vacuum filter. There are ten (10) vacuum filters in SGL.Here vacuum pressure about 30-35 cm Hg is applied by the vacuum pumps.Vacuum filters are use to remove sweetness from mud. Sweetness of input juice = 75% Sweetness in output juice = 2-2.5% Clear juice goes to turbid juice tank and then to reaction tank for further clarification.Mud is sent to bio-composting plant where after composting with stillage (waste of distillery) biocompost is prepared.

Evaporators: The clarified juice (85% water) in clear juice tank is pumped to evaporators where it is concentrated to a heavy clear syrup. Evaporation is done in multiple effect evaporators to achieve maximum steam economy .Each effect is arranged in series and operated so that each succeeding one operates under high vacuum (low pressure). This arrangement allows the juice to be drawn from one vessel to the next and permits it to boil at low temperature. Evaporation is done in two stages. The first in an evaporator station to concentrate the solution and second in a vacuum pan is to crystallize the sugar from solution. First step is done generally in multiple effect evaporators for improved thermal economy; and second is performed in single effect vessels e.g vacuum pans to control the batch crystallization. The evaporator station in raw sugar manufacture typically removes 90% of the water from the clarified juice from about 15 brix to about 65-70 brix. There are different terms, which are used here in factory for evaporators, bodies and quads are more common. When four bodies are combined then it is called quad.The triple, quintuple-effect evaporators are also used but quadruple-effect type is more common. In this one pound of steam evaporates four pounds of water. Juice from clarifiers goes to the vapor cell. Vapor cell is used before each quad for steam economy . There are three vapors cells. The exhaust Steam is applied on vapor cell and temperature is raised to about 110oC.Then juice goes to evaporator No.1. Its temperature is kept at 110o C. The Vapors of 1st body are used in 2 nd body as heating media and hence there is no use of steam in body No.2.

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Internship Report The temperature of 3rd and 4th body is 85oC and 60o C respectively. Creating vacuum of 60-65 mm Hg decreases the temperature of 4th body. The 4th evaporator is attached with condenser, which removes condensable gases through jet and condenses the vapors by spraying the cold water. Syrup of 60 to 65 brix is obtained from the 4th evaporator. Then this syrup is sent to syrup tanks called syrup storage tank. The cleaning of evaporator is necessary to maintain the brix. After 12-15 days every evaporator has to be cleaned. Summary of evaporation process is as such:

Clear juice: Temperature

890C

Pressure

1 kg / cm2

Brix

15

Vapor cell: Temperature

1040C

Steam inlet Pressure

0.31 kg / cm2

Vapor pressure

0.33 kg / cm2

Brix

22

Evaporator # 1: Temperature

1030C

Vapor Pressure

0.29 kg / cm2

Calendria pressure

0.37 kg / cm2

Brix

35

Evaporator # 2: Temperature

930C

Calendria Pressure

0.13 kg / cm2

Vapor pressure

0.11 kg / cm2

Brix

38

Evaporator # 3: Temperature

89 0C

Calendria Pressure

-17.88 kg / cm2

Vapor pressure

-28.13 kg / cm2

Brix 41

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Internship Report Evaporator # 4: Temperature

580C

Calendria Pressure

-29.38 kg / cm2

Vapor pressure Brix

-53.63 kg / cm2 s65

Syrup storage tank: Syrup from syrup storage tanks is sent to syrup storage tank,from there it is sent to raw crystallization pans.

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Raw crystallization: Syrup from evaporators is pumped to a vacuum pan in which it is evaporated to supersaturation in order to cause sugar to crystallize .This is done in pans which may be either Batch pan or Continuous vacuum pans The function pan is to produce satisfactory sugar crystals from syrup. The concentration of feed used in pans is usually 60-65 brix and may reach to 74 here. These pans are specified for different boiling of different massecuite and seeds. Batch Pan # 1,2 Seed for A massecuite, Continuous Pan # 1,2 forA-massecuite ,Batch Pan # 3 seed for c-massecuite, Continuous pan # 3 for c- massecuite and Batch Pan # 4,5,6,7,8 for B-massecuite

Massecuite = molasses + crystals Crystallization is done through following pans that work mutually. A pan B pan C pan

A pan: Syrup from syrup storage tank is taken into A pan. Through vacuum boiling brix level is increased to 70, where crystals start to form. Vacuum boiling (pressure 76 mm Hg) is done at 60°C. Now A massecuite is done by the addition of B seed( added upto 1/4 or 1/8 of total tank volume). Here A grain (brix 90-95) is formed that is further transfer to continous vacuum pans continuous vacuum pans consists of 12 parts where syrup and A grain is brought in contact to each other in tubes and steam is applied as heating media. The product from continous pans is A massecuite and that is dropped into A crystallizer by vacuum breakage. Sugar is formed with in three to four hours. This material is further transferred to A centrifugals where high . In centrifugals speed is applied separate grain of sugar and molasses comes out. These machines work mechanically, centrifugal force works when basket of the centrifugal rotates with high speed i.e 1600 rpm. There are 10 Nos. of A-centrifugals, 9 Nos. of B centrifugals, 8 Nos. of C centrifugals. From the centrifugation of massecuite A, A melt, A heavy and A wash are obtained. Raw melt is sent for clarification while A heavy and A wash are brought into B pans for preparation of massecuite B. No of tubes in batch pan A = 840 tubes Diameter of each tube

= 100 mm

Length of each tube

= 1300 mm

Vacuum pressure

= 76 mm Hg

B Pan: There are five nos. of B pans in SML. Physical parameters are same as that is pan A. Here B massecuite is formed which is dropped into B crystallizer. Centrifugation of massecuite gives B seed and B heavy. First of all B seed that is used for A massecuite is prepared by slurry ( crystals + isopropyle alcohol) and syrup. Isopropyl alcohol is added for proper size of grains. No of tubes in batch pan B = 840 tubes

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Internship Report Diameter of each tube

= 100 mm

Length of each tube

= 1300 mm

Vacuum pressure

= 76 mm Hg

C Pan: There is a single C pan in SML. Here C massecuite is prepared from B heavy taken from B pans and slurry. Here C grains are formed that are than droped to C continous pan where syrup is added and product is than sent to vertical crystallizers( two in numbers) then it is sent to cassettes (four in numbers)where temperature is dropped to 40°C which is best temp. for crystallization. Then it is sent to reheaters (four in numbers) The purpose of reheaters is to increase the temp. of massecuite to such a level suitable for centrifugation. Centrifugation (single curing centrifuges) of massecuite C gives C seed along with final molasses. This final molasses is sent to distillery for production of alcohol. C seed is sent to double curing centrifuges from where we get C Light (purity 56 to 58) and C seed that is used for preparation of soft sugar. No of tubes in batch pan B = 840 tubes Diameter of each tube

= 100 mm

Length of each tube

= 1300 mm

Vacuum pressure

= 76 mm Hg

CRYSTAL SIZE: A massecuite = 0.7 nm B massecuite = 0.5 nm C massecuite = 0.3nm

CRYSTAL % AGE: A massecuite = 55 % B massecuite = 45 % C massecuite = 38 %

BOILING TIME: A massecuite = 2 to 3 hours B massecuite = 3 to 4 hours C massecuite = 4 to 6 hours

Sugar Refining: The raw sugar produced in industry as described in preceding section is LIGHT BROWN in colour and contains 98% sucrose .In order for it to be competitive for marketplace, it is necessary to bring about level of sucrose to 99.9% to make it white. There are four routes for production of white sugar from sugar cane or raw cane sugar . (1): traditional plantation white , obtained directly from sugar juice with settling clarification and sulfitation. (2): improved plantation white with carbonation and sulfitation. (3): refined white, from a white end refinery attached to raw sugar factory, involving remelting raw sugar and

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Internship Report refinery classification and decolorizing process; and (4) refined white, refinery not incorporated into raw sugar factory.

Phosphitation Process: A-melt which is the final product of the raw process is further transferred for melt clarification. The process involves following steps. .

Buffer tank Raw melt goes into buffer tank. Its purpose is to store the raw melt. The capacity of buffer tank is 65 cubic meter.

Supply tank: Raw melt from buffer tank comes into supply tank situated at ground flour.

Liquor Heaters: Liquor from supply tank is sent to liquor heaters for heating up to 80 to 85°C that is suitable for purification. Outer diameter of each tube Thickness of tube walls

= 38 mm = 1.25 + 1.25 = 2.50 mm Inside diameter of each tube = 38 – 2.50 = 35.5 mm Length of each tube = 4500 mm Total no. of tubes in each primary heater = 408 tubes No. of passes in each primary heater = 12 No. of tubes in each pass = 34 Juice heating temperature = 80 - 850C Heating surface = 3.1416*d*l*no.of tubes = 3.1416 * 35.5 * 4500 * 408 = 204763204.8 mm2 = 204.7632048 m2 = 2204.05273 ft2

Reaction tank: After heating the product is taken into reaction tank. In reaction tank following chemicals are added. • • • •

Phosphoric acid (300-400 ppm) Talofloc : It is used as decolorizing agent Talofloat: It is used to float the ppt. sludge, colloidal solution so that it can easily removed from the upper surface. Lime Socrates: To maintain the pH of the raw melt.

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Telo Clarifiers: From reaction tank the liquor comes in telo clarifiers. Due to the addition of low molecular weight coagulants (Taloflot), the mud floats on the surface of liquor. Here mud is collected with the help of scrappers and sent to vacuum filters. Liquor is collected into liquor tank and sent for sulphitation.

Sulfitation/sulfer tank: Sulphitation is an eminent process done to decolorize the liquor. For this purpose liquor is taken in a tank and SO2 is passed from the bottom of this tank. After sulphitation liquor is collected into smear tank and then passes through pressure filters with the help of pumps.

Filteration: The liquor from phosphatation/ carbonation/ sulphitation clarifiers contain small amount of finely dispersed particulate matter that require filteration for removal . This process is done in the pressure filters

Pressure filters: There are eight pressure filters in SML, four are big and four are small. Small press. Filters have 48 plates and 24 out let and large press. filters have 36 plates and 24 out let. Here small dust particles are removed and clear liquor is obtained. Pressure upto 1-2 kg / cm2.

Deep Bed Filters: Liquor from vacuum filters is sent to deep bed filters where layers of different sizes of stones are applied for further filtration. Fine liquor is dropped from top and moves towards bottom. Layers classification are as such: ………………………….. (carbon media) ……………………..… (sand)

…………………… (3 mm)

……….………… (6 mm)

..…………….. (12 mm)

……………… (18 mm) Decolorization: The filtered clarified liquor is a clear, dark brown liquid having solid contents b/w 55 to 65 Brix, a pH of 6.7 to 7.2 and temperature b/w 65-----85oc. At this stage certain decolorizing agents are added to remove colour such as charcoal ,bone char , ion exchange resins etc and this send for refine crystallization and centrifugation in the refine pans and centrifugals which are discussed as next topic .

Refine crystallization and centrifugation: Clear liquor obtained after melt clarification is brought into refinery pans for final crystallization. There are six nos. refinery pans in SML.

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Internship Report Massecuite Charging: First of all massecuite is drawn from refinery crystallizer at 200 rpm.

Washing with hot water: Then this massecuite is washed with hot water coming from nozzles. Water comes out for few seconds. The purpose of washing is to wash the sugar and to make it white.

Steaming When hot water stops, then steam comes from the same nozzle for few seconds. The purpose of this steaming is to dry the sugar.

High spin Centrifugal rotates with high speed almost to 1600 rpm.

Ploughing Then machine starts to stop with low speed. It rotates with 50rpm.

Discharging Then centrifugal is discharged by dropping the sugar into the hopper. In refinery centrifugal we can refine 1500 kg sugar at once.

Sugar Drying And Grading: Sugar obtained from centrifugals contains 1---2% moisture and is too wet to be placed in storages or packages .The wet sugar is fed to drying equipment called granulators , which are usually rotating drums , 15------35 feet long and 6------7 feet in diameter , inclined slightly so as to be discharged by gravity . Heated air is blown through dryer concurrent with the flow of sugar. Two types of granulator are used commonly either Roto –Louver granulator or Standard Hershey granulator. The 1st one consists of a single rotating drum in which hot air from Louvers in the wall dried a moving bed of sugar .The Hershey granulator consists of a rotary dryer followed by second unit in which sugar is cooled to 45 to 55oc after leaving the dryer at 52---55 oc. Sugar is then graded to A, B and C grades depending on size of grains and their purity. Then sold to market after packaging in the bags.

Packaging and storing of refined granulated sugar: In recent decades, there have been significant changes in the methods of handling refined sugar as it leaves the dryer. Bulk delivery of refined granulated sugar to customers has made it necessary for the refiner to store finished products in bulk rather than in bags .Granulated sugar remains free flowing for a long period of time if it is CONDITIONED as conditioning reduces the handling , packaging and storing problems resulting from caking.Conditioning involves following factors , including control of moisture contents , the temperature ,and grain size , as well as good inventory management .

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Analysis Of Intermediate Products Of Sugar Different samples of juice are collected for the determination of brix and pol. One sample is collected from clarifier, three from mill No.1 and three from mill No.2 after 1 hour. The sample collected from last mill called “last mill sample.” It is collected from front side of last mill. The sample collected from 1 st mill is called “1st sample”. It is collected from backside of 1st mill. The sample collected from rotary screen is called “mix sample” Sampler collects samples during each hour after 5minutes and conveys to the lab after one hour

Brix determination: The equipment used for the measurement of brix is called brix hydrometer. The sample is added in hydrometer measuring cylinder and then brix hydrometer is put down into it. It floats and gives the reading of brix at any temperature. Then this reading and temperature are seen in table. For example our Observed brix reading is 19.6 at 26oC temperature. Draw a line horizontally from temp and vertically from brix reading. It will give “temperature correction”. For observed brix reading 19.6 at 26o C Temp, correction is 0.40. Then corrected brix is calculated from formula. Corrected brix = Observed Brix + Temp. Correction = 19.6 + 0.40 For brix reading at temperature lower than 20C. It is not added but subtracted. Then sample is mixed with half spoon of lead acetate and filtered. The pol reading of clear solution is measured by sucromat. Suppose it is 63.

Pol % determination: Pol% is determined by using table. Draw horizontal line from pol reading and vertical line from brix reading. The joining point will be the Pol%, but if you have pol value in decimal like 19.6. Then add 0.6 reading value to it. Purity is determined by the following formula. Purity = Pol% / corrected brix x 100

Dilution Corrected =

brix of 1st sample −corrected brix of mix sample Corrected brix of mix sample

×100

Example: If following is the data than we can determine the purity as follows; Brix 19.6 Temp. 26 Temp. Correction 0.40 Corrected brix 19.6 + 0 .40 = 20

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Internship Report Pol Pol % Purity:

=

63.4 16.22 + .10 = 16.32 Pol %/ corrected Brix*100

Inlet spray pond and outlet spray pond The sample is taken from pond coming and going out of the boiling house. We determine its pH and pol. This tells us the sugar in inlet and outlet pond. The pH of this water should be around 7.2, 7.3. Samples are analyzed twice a shift. Drain water pol determination: The sugar goes into the drain water of glands of the pumps leak or some spillage occurred. We determine pol. of drain water. This leads us to determine the sucrose in drainage water. Sample is analyzed twice a shift. Mud: Mud sample is drawn from rubber belt below the vacuum filters and is mixed thoroughly. We take 50g mud from mud sample and dilute to 200mL. Then we determine pol after clarification. It tells us the sugar loss in mud. Mud sample is analyzed twice a shift. Bagasse pol determination: For bagasse pol determination, we take 550 of bagasse and 7900 ml of H2O (1/4 normal) in Jeff co machine. Then we run machine for 5 minutes. The aliquot is clarified with lead pol% is determined. Bagasse sample is analyzed twice in a shift. Analysis of Syrup, A. melt, Polish melt samples: Syrup samples are taken from the 4th body of evaporators and from pan storage tank. Sample of A. melt is taken from the density bottle at A. centrifugals. Sample of polish melt is taken from sulphitation tank. Samples of A. melt and polish melt is analyzed twice a shift and syrup sample is analyzed after two hours. We take 250g of sample and dilute it to 1000 g. We determine Brix and pol% to get purity. Analysis of Massecuite, Seed, A.H, A.W, B.H and Final Molasses: Massecuite A, C, B-seed, C-seed, Pan Syrup, B Heavy, A Heavy and A Wash are analyzed one time in a shift. We take 100 g of sample and dilute to 1000g with water. We determine Brix and pol% to get purity. Single cured seed, Final molasses, C Lite are analyzed twice a shift. We take 100 g of sample and dilute to 1000g with water. We determine Brix and pol% to get purity. Analysis of Refinery Masscuite: R1, R2, R3 masscuites are called refinery masscuites. We take 100 g of sample and dilute to 1000 g with water. We determine Brix and pol% to get purity. These masscuites have no limits. Analysis of Raw Sugar. Following tests of raw sugar according to ICUMSA method (explained latter) are performed daily.Approx.results are given below as

Analysis of sugar All tests are carried out by ICUMSA method in Process Labortory.Icumsa means International Commission of Uniform methods of sugar analysis. This commission was made by Germany in 1897. By ICUMSA, there are three types of methods given below as a) Official Method b) Accepted Method c) Tentative Method First of all, tentative method develops, after combining results it becomes Official. After recommendation from long time, it becomes accepted. There are specifications by

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Internship Report Icumsa as: Raw Sugar method known as G.S-1. White Sugar as G.S-2. G.S-2 . Special Sugar as G.S-3 . Molasses as G.S-4 . Sugar Cane etc G.S-5 Now I give an account of some tests/experiments which are mainly used in process. Labortary of shaker gang mills limited Toba Road Ghang and recommended by ICUMSA (international commission of uniform methods of sugar analysis)

EXPERIMENT Determine the Moisture of Refined Sugar using G.S 2/1/3-15 method (Loss on drying method) Apparatus: Oven, Dissector, Glass, Aluminum, Platinum Dishes (No heavy but light thickness) , Balance (0.1mg accuracy) and Thermometer (Electronics) Method/Procedure:

• • • • •

• •

• • •

Dry aluminum/glass plates (two) at 105 oC in oven for 30 min. Place it in dissector till its temperature becomes two degrees above room temperature. Take 20-30g sugars in both Petri dishes such that its layer is not more than 1cm. Keep it in oven for 3 hour. Again keep it in dissector till its temperature becomes two degrees above room temperature. Loss on Drying%=100(m2-m3)/(m2-m1 ) Where m1=wt of empty dish m2 =wt of dish +sugar (Before keep it in oven)

m3 = wt of dish +sugar (After drying) Results expression: Take mean of both results. In sugar loss on drying is only of water and it is usually less than 0.5 %. Not keep any other chemical in oven during moisture of sugar. No constant weight on balance is required. EXPERIMENT Determine the polarity of refined sugar using G.S 1/2/3-1 method: APPARATUS 100 ml measuring flask, Analytical Balance, thermometer, sucromat, watch glass CHEMICALS Sugar, distilled water.

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Internship Report PROCEDURE • Take 100 ml measuring flask and weigh 26 g of sugar in watch glass using Analytical Balance. • Transfer this sample in the 100 ml measuring flask and add 60- 70 ml of distil. Water. • Shake till all the crystals have been dissolved; make up the volume up to 100 ml by keeping the flask before the eyes. • Mix and filter, discard first 20 ml of filtrate • Note the temperature of the solution-using thermometer • Fill a 200 mm pol tube and put it into the sucromat and read • Determine the polarization for temperature by using the following formula • Polarity(pol) = Pt + (0.0015 x (Pt – 80) x (t-20)) • Where t = Temperature of Solution • Pt = Pol reading at Temperature t EXPERIMENT Give an assay of Color of Refined Sugar using GS 2/3-10 Method APPARATUS Conical flask, 0.45 micrometer pore size membrane, spectrophotometer, Abbemat.

vacuum

pump,

CHEMICALS Sugar, distilled water. PROCEDURE • Weigh 50 g of refined sugar in a conical flask. • Add 50 g of distilled water. • Dissolve the sugar till all crystals dissolves. • Filter the solution through 0.45 micrometer pore size membrane with the help of vacuum pump. • Calibrate the spectrophotometer with distilled water filtered through above membrane at 420 nm. • Pour the filtered sample in a quartz cell and place in the chamber of spectrophotometer and note the absorbance of sugar solution. • Note the brix of sugar solution with the help of Abbemat. Calculation Color of refined sugar =

Absorbance x 1000 ---------------------------------Concentration x Cell Length

Results expression Color of sugar is always indicated in I.U (Icumsa Unit). Precaution This method is only valid when color of sugar is below 50 I.U. EXPERIMENT Give an account of Color of Raw Sugar using GS 1/3-7 Method APPARATUS 0.45 micrometer pore size membrane, vacuum pump, spectrophotometer measuring cylinder.

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Internship Report CHEMICALS: Raw Sugar, distilled water. Procedure • Brix is adjusted to obtain absorbance range from 0.17 to 0.70. • Dissolve the sugar till all crystals dissolves.

•

Adjust PH of solution up to 7.0 with the help of 0.1 M (HCl) or 0.1M (NaOH). • Filter the solution through 0.45 micrometer pore size membrane with the help of vacuum pump. • Calibrate the spectrophotometer with distilled water filtered through above membrane at 420 nm. • Pour the filtered sample in a quartz cell and place in the chamber of spectrophotometer and note the absorbance of sugar solution. • Note the brix of sugar solution with the help of Abbemat. Calculation Absorbance x 1000 Color of raw sugar = ---------------------------------Concentration x Cell Length Expression of Results: Color of sugar is always indicated in I.U (ICUMSA Unit). Precaution: This method is only valid when color of sugar is above 250.

EXPERIMENT Check quality of given sample of alcohol Samples to be drawn from 24 hours production for operated Plants. Start G.C well before injection so that it achieved the desired conditions. Load the standard method and inject 0.5 micro L of sample. Get the results such as Methanol, Ethyl Acetate, Acetaldehyde, so Propyl Alcohol, Fusel Oil etc.

Cane Molasses The final mother liquor obtained during the processing of sugar cane into sugar is known as cane molasses. ANALYSIS OF MOLASSES: EXPERIMENT Pol Determination APPRATUS Wide mouth glass bottle, filter paper, sucroma, stopper. CHEMICALS Lead acetate, molasses sample. PROCEDURE

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Transfer about 120 ml of above sol to wide mouth glass bottle. Add 2-3 g of lead acetate and stopper it. Shake well and filter the solution. Discard first 20 ml of filtrate. Rinse a 200 mm observation pol tube with portion of solution, fill and place it in the sucromat for reading and note it. With the help of table, its pol% is to be determined. By knowing corrected brix and pol%, purity can be determined by following formula

•

Purity = Pol% x 100/ corrected brix EXPERIMENT NO 2 Sucrose% In Molasses APPARATUS: Spatula, two 100ml measuring flasks, filter paper spatula. CHEMICALS Molasses sample, NaCl solution, Lead sub acetate, HCl solution, distilled water. PROCEDURE • Take 1000 ml of 13% of final molasses solution. • Add 20 – 25 g of Lead sub acetate, mix with spatula and filter the solution • Transfer the filtrate in two 100 ml measuring flasks, 50 ml each. • In the first flask, put 10 ml of NaCl solution (231.5g + Dist. Water = 1000 ml ) add •

distilled water to make volume up to 100 ml

•

In the second flask, put 10 ml of HCl (350 ml HCl + 200 ml dist. Water) and heat it up to 65oC for a short while. Allow cooling the second flask in the air to room temperature and make volume up to 100 ml. Filter the solution through filter paper. Examine the pol in 200 mm pol tubes of both flasks.

• •

•

First pol will be the direct pol & 2nd pol will be the inverted pol. Calculations Sucrose %

=

Direct pol – Inverted pol / (132 – (0.5 x (t- 20)) x 4x 100

EXPERIMENT NO 3 Determine the amount of reducing sugar present in molasses. APPRATUS: Burette, pipette, Erlenmeyer flask, electric heater. CHEMICALS: Potassium Sodium Tartar ate, distilled water, sodium Hydroxide solution, molasses sample. PROCEDURE

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Internship Report Take 25 ml of 10% diluted molasses in the burette.

• • • •

Pipette 5 ml of fehling A(69.278g of CuSO4 in one L distilled water) and 5 ml of Fehling B (346g of Potassium Sodium Tartarate in 400 ml d-H2O+100g of NaOH in 300 ml d-H2O ,shake well and make its level up to 1 L with d-H2O) in Erlenmeyer flask. Add 20 ml of d-H2O and add 2-3 ml of diluted molasses from burette in above solution. Place the flask on an open top electric hot plate and heating it to boiling. Continue boiling for exactly two minutes. Add five drops of methylene blue indicator, color of solution becomes dark. While heating, titrate it against solution from burette till reddish color appeared. By knowing ml used of 10% diluted molasses and with help of table, reducing sugar and total sugar of molasses can be determined. Sucrose% Sugar as Invert = ------------+ R.S % 0.95 Total sugar = Sucrose% + R.S%

EXPERIMENT NO 4 Determination of Brix of given molasses sample APPRATUS: Beaker analytical balance, Brix hydrometer, 500 cylinders. CHEMICALS: Molasses sample, distilled water. PROCEDURE • Tare a large metallic beaker on a balance. • Weigh 100 g of molasses in it. • Add distilled water to a total weight of 1000 g. • Stir until molasses is thoroughly mixed with water. • Pour it into a 500ml cylinder until it overflows. • Lower the clean spindle into the cylinder after the air bubbles have escaped. • Blow away the froth and solid matter floating at the surface of the liquid while • • • • •

Lowering the Spindle. Lower the spindle until it floats freely. Make sure that the spindle does not touch the sides or the bottom of the cylinder. Let the spindle float for 2 minutes. Note the reading where liquid meniscus intersects the Scale. Note the temperature

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Internship Report • •

With the help of table, corrected brix can be determined as Corrected Brix = (observed brix+ temperature correction) x10

BRIX: The Brix scale is a density scale for sugar (sucrose) solution. The degree brix are numerically equal to the percentage of sucrose in solution. The term brix solid refers to the solids as determined by brix hydrometer.

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