Rubbish Journal

CALORIFIC VALUE OF RUBBISH PRODUCED IN MATARAM Mirmanto Mechanical Engineering Department, the University of Mataram Jl. Majapahit no. 62, Mataram, NTB, Indonesia 83125. e-mail: [email protected]

ABSTRAK Sampah adalah barang-barang yang tidak digunakan lagi dan merupakan hasil aktivitas makluk hidup atau industry. Sampah merupakan maslah bagi masyarakat dan lingkungan. Sampah menjadi masalah yang serius di kota Mataram. Manajemen pembuangan atau pengolahan sampah belum tertata dengan baik dan jelas. Sebagian masyarakat membuang sampah kemana saja termasuk ke sungai atau selokan dan sebagian lainya memilih untuk membakar sampah dari pada dibuang. Pemerintah dalam mengelola sampah masih menggunakan cara-cara konvensional yaitu mengumpulkan sampah dan membuangnya di TPA. Tidak ada aktivitas yang memanfaatkan sampah. Sebenarnya sampah dapat digunakan untuk mendukung kegiatan manusia. Penelitian terhadap sampah telah dilakukan. Bomb calorimeter dapat digunakan untuk memprediksi kalori dari sampah atau energy yang dikandung oleh sampah. Alat ini membakar sampel sampah dan menghasilkan temperature tertentu. Perbedaan temperature sebelum dan sesudah pembakaran memiliki kaitan dengan energy yang dibebaskan saat pembakaran. Penelitian menunjukan bahwa sampah plastic memiliki nilai kalor (energy) yang paling besar yaitu 12415,72 cal/gr. Karet, makanan, daun, kayu dan aneka kertas masing-masing memiliki nilai kalor 8640,8 cal/gr, 5875,57 cal/gr, 5334,49 cal/gr, 5975,59 cal/gr dan 4425,75 cal/gr. Sampah makanan prosentase kadar air yang palin tinggi yaitu 70,66%. Sampah daun menempati komposisi 20,65% dari total volume sampah produksi masyarakat kota Mataram. Kata kunci: Sampah, kadar air, nilai kalor dan komposisi. ABSTRACT Waste (rubbish) is unused matter resulted by life creature activities or industries processes. Waste is daily problem for the community and environmental. Waste becomes problem seriously in Mataram Town. Management of rubbish disposal is not clear enough yet. Some people throw rubbish anywhere, others throw it in to the river, and the rest burn it on the ground. Government manages the rubbish with conventional way. The rubbish is collected from several places and the thrown to the rubbish disposal (TPA). No activity advantages rubbish. Actually, rubbish has some advantages for supporting human being activities (life). Research on rubbish energy has been done. Bomb calorimeter can be used for predicting the waste’s calorific value. It burns the rubbish powder and results certain temperature. The difference temperature before and after combustion process indicates some energy released. The result shows that plastic waste has highest calorific value than others. It has calorific value 12415.72 (cal/gr). Rubber, food, leaf, wood, mixing papers have each calorific value 8640.8 cal/gr, 5875.57 cal/gr, 5334.49 cal/gr, 5975.59 cal/gr, 4425.75 cal/gr respectively. Food has greatest water contained than others. It has 70.66% of water contained. Leaf has highest percentage of waste composition in Mataram. It is about 20.65% of total waste volume. Keyword: waste (rubbish), moisture content, calorific value and composition 1

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burn it respectively. Actually, rubbish can

INTRODUCTION Waste is unused stuff (material).

be used for fertilizing, or be converted to

Usually, it is as a side result of human

become fuel or briquette.

being activities or industries processes.

Mataram Town can result electrical power

Population and human being activities

of 3.25 MW (Wiradarma, 2002). Based on

increase, so that wastes volume increase as

the BPPS 2002 data, population of

well.

Mataram

Town

consists

Rubbish in

of

27.759

Waste causes several problems for

households. If each household needs 1.3

human being and environment. Rubbish

KWH, so that Mataram needs at least 36.1

existence generates the growth of flies,

MWH. This research objects to knowing

mice, and others. It also makes ground, air,

the calorific value of rubbish produced by

water

human being or industry activities in

and

environmental

be

contaminated/polluted. Waste serves rotten

Mataram. The amount of maximum heat

smell as result of decomposition processes. Decomposition

process

results

CO2,

energy

released

from

fuel

during

methane and others. Un-organic waste

completed combustion process is called

causes the land unprocessed, bad view,

calorific value (Anonymous, 2005). It has

and flooding as well as health disturbance.

unit kJ/kg or kcal/kg.

Based on the data from Dinas Kebersihan

Mataram

2004,

waste

3

production reaches 1029 m a day. The biggest composition of rubbish volume is waste from community dwelt. It reaches 525 m3 a day or 51.47% of total volume. Only 76.37% of total volume has been thrown to the waste disposal place (TPA). In other words, waste in Mataram will make serious problem in the future. Advantaging

waste,

until

nowadays, is not conducted yet. Many people throw rubbish to anywhere they like such as river, TPA, other places etc or

Table 1. Calorific value of several wastes Waste Calorific value (kJ/kg) Food 2,864.79 Papers 1,104.39 Plastic 2,077.56 wood 498.5 Textile 584.76 Rubber 550.83 Source: Ahmad, R. (2004) To generate electrical power, waste must hold high calorific value.

Wastes

such as plastics, wood, food, papers etc can be used for generating electrical power because they have high calorific value. Plastic has calorific value 6000 calories, 2

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 papers have 4000-5000 calories and leafs have 5000 calories (Apriadji, W.H, 1995). Waste

contains

50%

of

combustible waste (Budiman, 2005). Table 2. Energy produced from combustible materials. Material Energy content kJ/kg Btu/lb Town waste 10.500 4.500 Combustible 23.300 10.000 Papers 16.300 7.000 Organic waste 5.800 2.500 Solid deposit 17.700 waste Extraction of solid deposit 9.100 waste Oil fuel 46.500 - anthracite 28.000 - methane 49.000 Source: Eddy and Budi (1990).

7.600

According to reverence (Henry, J Glynn., 1989), rubbish can be classified as follows: a. Based on material contained: organic and inorganic rubbish. b.

Based on waste sources; household rubbish, industrial rubbish and life creatures waste.

c. Based on waste properties: - Food waste - Moldy waste and slowly moldy waste: wood, papers, can, iron etc.

3.900 20.000 12.000 21.000

Calorific value of several types of waste is presented below: Table 3. Energy produced from varies rubbish (waste) Rubbish Energy contents (kJ) Papers or carton 8.082 Wood 8.256 Wood branches 7.533 Leafs 5.170 Green grass 4.030 Fruits and vegetables waste 1.920 Textiles 6.795 Rubber 13.104 Leather 10.550 Papers candle covered 12.661 Plastic (Cellophane) 12.661 Plastic (polyethylene) 20.932 Plastic (polyvinyl) 18.464 Oil waste 18.991 Wet Semen 12.133 Source: Hadiwiyoto, S. (1983).

- Un-decayed waste: glass, plastics etc. Drying Drying process is a process of dewatering of material or substance until certain value. Process of drying contains two fundamental steps: 1. Heating is transferred from heating sources to the material heated. 2. Water mass is transferred to the heating sources. In other words, drying is a kind of mass and heat transfer phenomena, which occur simultaneously. Heat transfer occurs from high temperature to low temperature. The effectiveness of drying and combustion process depends on four conditions below (Anonymous, 1997): a. Vapor dispersion velocity b. Temperature difference

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 c. Steering process for accelerating the

Dry sample (Bk)

heat transfer d. Rubbish dimension Dry sample or other material can be

F = 100% – E Where: F = dry stuff (%).

classified into three models (Jupri, A. 2001):

Heating value:

a. As Fed

Heat analyzed of fuel objects to

b. Partially Dry

obtaining

heat

energy

released

in

c. Dry

combustion (El-Wakil, 1992). Heating value indicates the amount of heat released from perfect combustion. According to

Water contained When rubbish has high value of water contained, drying and combustion process need much energy. To know the water contained of dry stuff, someone can use an electrical oven for drying stuff at 105 oC (Elwakil, 1992). After being dried, dry stuff is analyzed by using equation

ASTMD standard 2015, heating value is determined by testing sample in Bomb calorimeter. There are two types of heating value; HHV and LHV. HHV is a heating value where H2O of combustion product is in the form of liquid, while LHV is a heating value where H2O of combustion product is in the form of vapor.

below: 

Heating value of almost dry waste is

Sample weight D=B–A Where: D = sample weight (gr). B = bowl and sample weight (gr). A = empty bowl weight (gr). Percentage of water contained:  B-C % water contained (E)    x 100  D 

Where:

called Gross Energy (GE).

ΔT  T2  T1  calorie of wire burned  (10  remain wir e) x 2,3 cal/cm

Where: Initial temperature is (T1) (oC) Final temperature is (T2) (oC) Temperature difference (∆T) - 2.3 (cal) is the amount of calorie needed for burning 1 cm of wire length.

C = bowl and sample weight, after being dried at 105 oC (gr). 4

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 Acid correction is usually used for testing GE wet  (2470 x T) - (wire heat  milliliter titration ) wet sample weight

sample that contains Nitrogen (N) and Sulfur (S). If acid correction is mixed with water, it results N2O3 and S2O3, which can

Where:

oxidize the water. Water oxidized can result

Wet sample weight is in gram, milliliter

HNO3 and H2SO4. Heat, which is released

titration is in calorie, GEwet (gross energy)

from HNO3 0.1 N in the bomb calorimeter,

is in cal/gram, wire heat is in calorie, 2470

is 13.8 kcal/ml.

(cal) is the amount of heat needed to increase 1 OC of stuff temperature, milliliter

MATERIAL AND METHOD

titration (Na2CO3) is heat correction of nitrate acid during combustion.

rubbishes that were taken from three

Analyzing the GEdry can use the equation below: GE dry 

Materials used in this research were Deposal places (rubbish disposal places) in Mataram.

100 x GE wet % Dry sample

Method was used in this research are:

Where: GEdry (gross energy) is in cal/gram.

a. Literature study: study the reverences that contain relevant topic with this

Chemical solution:

research.

Chemical solutions for heating value tested are:

heating value using bomb calorimeter.

a. Benzoate Acid: It has 6.32 kcal/gram of heating

value;

un-hygroscopic;

combustible.

Rubbish samples investigated were food rubbish, wood, plastic, rubber, papers.

b. Naphthalene: It has 9.61 kcal/gram of heating value.

Devices used were: a. Bucket.

c. Sucrose: It has 3.95 kcal/gram of heating value. Alkali

b. Weight scale. c. Ohaus weight scale.

d. Alkali solution is used for serving titration.

b. Experiment on determining rubbish-

solution

used

usually is Na-carbonate 0.0725 N, which is equivalent to 1 cal/ml. e. Methyl orange (methyl red indicator).

d. Analytical weight scale. e. Rubbish crusher. f. Brush g. Wood spoon. h. Oven 5

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 i.

Bomb Calorimeter unit

f. Install the bucket, which contains water.

j.

Bowl

g. Cover the calorimeter.

k. Thermometer

h. Switch on dynamo to steer the water.

l.

i.

Burette

m. Pipette

Connect the bomb calorimeter to the ignition unit and electrical power.

n. Pinsetter o. Flashing wire.

Testing:

p. Ruler

Clean bowl is dried in the oven at 105 oC as

q. Oxygen tank

long as one hour. After being heated, the

r. Beaker glass

bowl is cold in the desiccators for about 15

Reagents

minutes at room temperature. Then it is put

- Na2CO3 0.0725 N= 3.4821 gr/lt

on weight scale in order to know its weight.

- Methyl orange indicator (m.o)

Rubbish sample (1.5 gr) is put into the

After being taken from several

bowl. Sample and bowl together are placed

deposal places, rubbish samples were

into the oven as long as 8 hours at 105 oC.

separated by their classification. Samples

Next steps, they are cold for 15 minutes,

were putted on weight scale in order to

and then they are put on weight scale again

know their initial weight. They were dried

in order to know its dry weight.

under the sunshine and then were crushed Procedures of bomb calorimeter use

to be powder.

1. Check all devices completely and Procedure of bomb calorimeter used a. Clean the bomb calorimeter and its cover with water. b. Cut flashing wire 10 cm in length and install it. .

carefully. 2. Prepare the blank form for noting the data from Bomb Calorimeter and the time. 3. Run the dynamo for 5 minutes and

c. Put the bowl, which contains sample in to calorimeter, and adjust the flashing wire in order to touch the sample. 3

d. Put one mm of water into the bomb calorimeter.

note the temperatures appear in every minute. 4. At the fifth minute, burn the sample by turning on the red button on ignition unit.

e. Flow the oxygen into calorimeter with pressure of 35 atm. 6

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 5. Write the last temperature when the temperature shows the same degree or has been steady.

Table 1. The actual composition of several wastes in the disposal place. Waste types

6. Shut off the dynamometer. 7. Remove dynamo's steer. 8. Remove the bomb cover. 9. Remove the bomb and release the rest Oxygen by turning the button valve. 10. Take the bucket with clipper, wash the inside with water, pour the water

Food waste Papers Glass Plastic Wood/branch Textile Rubber Leaf waste Others Total

Waste weight (kg) 2.1 1.25 0.5 3.75 1.1 1.75 3 4.15 2.5 20.1

% 10.44 6.22 2.48 18.66 5.47 8.71 14.93 20.65 12.43 100

washer into beaker glass. 11. Wash the bomb with water, pour the

Kebersihan (2005), Mataram produces

water washer into beaker glass.

waste 1020 m3/day, but the waste that can

12. Penetrate the water washer with Na2CO3 0, 0725 N solution and methyl orange (m.o). 13. Remove the flash wire, straight it and measure its length.

The research data are served in tables and graphs below. Actual waste composition To determine the actual waste in

the

reach the disposal place is only 76.37 % or 779 m3 a day. Therefore, the prediction of waste composition becomes as follows: Table 2. Prediction of waste composition in the disposal place.

RESULT AND DISCUSSION

composition

Based on the data from Dinas

disposal

place,

researcher took 20.1 kg (0.1256 m3) of

Types of waste Food waste Papers Glass Plastic Wood Textile Rubber Leafs Others Total

Waste Volume (m3/day) 81.39 48.45 19.38 145.34 42.63 67.82 116.27 160.84 96.89 779

% 10.44 6.22 2.48 18.66 5.47 8.71 14.93 20.65 12.43 100

waste samples. They were then classified in accordance with their groups.

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 Water contained

contained in the sample. Thus, this work

 w  w2 % Naturaly water contained   1  w1  2534.6  1087.5    x100%  57.09% 2534.6  

results the percent of wet and dry weight

Calculation of water contained lost from

of sample. This testing is done on the

stuff (leaf waste) is able to be done by using

sample, which is dried first under the sun

formula below:

with

 Sample weight

Testing the water contained is in order to know the percent of water

neglecting

the

environment’s

influence.

D=B–A

After all of samples are scaled by using

analytical

  x100% 

weight

scale,

each

maximum weight is 1.5 gram, they are dried in the oven at 105 oC. The testing, that has been done, resulted data as follows: Table 3. Percentage of water contained of samples dried under the sun Types of w1 w2 Water waste (gr) (gr) contained (%) Leafs 2534.6 1087.5 57.09 Food 5511.7 1840.4 66.61 Wood 1288.8 902 30.01 Papers 2735.9 2317.5 15.29 Plastics 2052.8 1333.1 35.06 Rubber 668.1 657.1 1.65 Calculating percentage of water contained lost during drying process under the sun can be done by using formula below:  w  w2   x100% % Naturally water contained   1  w1  Example of calculation for leaf waste:

D = 21.1987 – 19.6970 D = 1.5017 gr  (%) Water contained B-C % water contained (E)    x 100  D  % water contained (E)  21.1987 - 21.0845    x 100 1.5017    7.6047 %  (%) Dry weight

F = 100% – E F = 100%– 7.6047% F = 92.3953 % c. Total water contained To know total water contained, one can use equation below: Calculation example for leafs waste. % Water contained = % naturally water contained + % water contained dried in the oven at 105 oC % Water contained = 57.09 % + 7.6926 = 64.7826 %

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 Heat released from waste combustion

 Dry Gross Energy (GEd)

Testing energy is for knowing the

100 xGE w % dry stuff 100 GE d  x 4920.2173 92.3074 GE d  5330.2523 cal/gr GE d 

calorific value, which is contained in rubbish

produced

by

community

in

Mataram. Types of waste that were tested are leafs, papers, rubbers, plastics, woods and foods. Calculation

of

testing

energy

contained in wastes can be done by using equation below: An example calculation for leaf wastes:

Based on testing data, which is found from experiment, and actual waste composition data, one can determine the amount of total energy contained in each sample.

Known: Tinitial = 25.60 oC Tfinal

= 27.70 oC

Titration milliliter

= 6.80 ml

Dry stuff

= 92.3953%

Sample weight

= 1.0491 gram

 Temperature difference (∆T) ΔT  Tfinal  Tinitial ΔT  27.70 - 25.60 ΔT  2.10 o C

 Heat of wire burned Heat of wire burned  (10 - rested wire)x2.3  (10 - 2)x2.3  18.40 cal

 Wet Gross Energy (GEw) 2470 xΔT - (Titration milliliter ) GE w   Sample weight heat of wire burned Sample weight 2470 x2.10 - (6.80) - (18.40) GE w  1.0491 GE w  4920.2173 cal/gr

Table 4. Calorific value of wastes in Mataram No. Waste Composition Calorific types (%) value (kJ/kg) 1 Leafs 20.65 4612.0587 2 Foods 10.44 2568.222 3 Woods 5.47 1368.516 4 Glass 2.48 5 Papers 6.22 1152.548 6 Plastics 18.66 9699.867 7 Textile 8.71 8 Rubbers 14.93 4151.095 9 Others 12.43 Total 23552.30 Sarofim (1977, in J Glinn Henry, 1989) revealed that energy contained in combustible materials such as organic waste was 5800 kJ/kg. As shown in table 4, total combustible organic waste is 22.13 % or 333.36 m3.

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

80.00

Leaf s 20.65%

70.00 60.00

Glass 2.48%

% total water contained

Textile 8.71%

Others 12.43%

50.00

Food 10.44%

Rubers 14.93%

Wood 5.47% Plastics 18.66%

Papers 6.22%

40.00 30.00 20.00 10.00 0.00

Leafs

Food Spesimen

Papers

Figure 1. Waste composition in the disposal place

Plastics

Woods Rubbers

Figure 2. Water contained of waste

As shown in figure 1, leaf has highest percentage that is 20.65% from

As shown in figure 2, food’s water

total waste volume in the disposal place.

contained

is

74.66%,

However, Achmad R (2004) elucidated

contained

is

that waste such as yard rubbish, kitchen

contained is 43.76%, plastic’s water

rubbish, papers and so on dominates waste

contained is 35.63% and paper’s water

composition.

contained is 21.47% as well as rubber’s

64.79%,

leaf’s

water

wood’s

water

Composition of food waste in

water contained is 3.22%. Food’s water

temporary disposal place differs from that

contained occupies biggest percentage

in TPA because animals eat food waste in

than others because food does not only

TPA. Therefore, composition of food

contains of much water but also gets much

waste in the temporary disposal place is

water when it is processed. Thus, it is

greater than that in the TPA. In addition,

confident that food has greatest water

rubber waste almost consists of tire waste

contained. Plastic also contains much

and sandal waste.

water because it is produced from plastic stuff and water. Figure 3 shows wet gross energy of several types of waste. Plastic has the highest wet gross energy because it has high temperature difference when it is 10

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 tested in the bomb. This temperature 14000

stuff composition. Bound of plastic’s stuff

12000

composition is too strong so that it needs a lot of energy when it is decomposed. Higher temperature difference resulted bigger energy needed. In addition, other wastes have no bound as strong as that belongs to plastic, so that they have lower calorific value. However, rubber waste has bound close to that of plastic so that rubber has almost the same calorific value to that belongs to plastic.

Dry Gross Energy (cal/gr)

difference is resulted by bound of plastic’s

10000 8000 6000 4000 2000 0 leafs

Food

Woods

Papers

Plastcs

Rubbers

Figure 4. Dry Gross Energy of several types of waste. Research

Wet Gross Energy (cal/gr)

from Enri’s result. Enri (2005) revealed that calorific value of paper was between 4000 to 5000 kcal/kg, while this research

2000 0

resulted calorific value 18531.5 (kJ/kg) or

Leaf s Papers

Food Plastics

4412 (kcal/kg).

Woods Rubbers

Figure 3. Wet Gross Energy of several types of waste. 4

indicates

the

same

phenomena of calorific value of several types of waste. It is believable because calculation

particularly

calorific value of paper, are not too far

14000 12000 10000 8000 6000 4000

Figure

results,

of

dry

gross

energy

is

proportional to wet gross energy. Greater wet gross energy had, greater dry gross energy had as well. Therefore, plastic has the greatest dry gross energy than others.

CONCLUSION AND RECOMMENDATION After collecting and analyzing data resulted from research, researcher can make conclusion as follows: a. Highest

composition of waste

in

Mataram is leaf waste (20.65%). b. Highest water contained percentage is about 74.66%, which belongs to food waste. 11

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 c. Lowest water contained percentage is about 3.22%, which belongs to rubber waste. d. Plastic has highest calorific value than others. Plastic’s calorific value is 12415.72 (cal/gr), while paper has lowest calorific value. It is about 4425.75 (cal/gr). e. Harder to be decomposed higher calorific value had. f. Wastes such as leaf, paper, wood, food etc, are combustible wastes that occupy 22.13% (333.36 m3) of total wastes in Mataram. g. Calorific value of materials depends on the material composition. Recommendation a. It is better to examine chemical composition of wastes for determining calorific value. b. It is necessary to do research further about wastes usage such as for electrical power generation instead of disposing them only. c. It is recommended that solid waste crusher, waste dryer etc be produced in order to make research be easier.

REVERENCES , 2002, Sekilas, Dinas Kebersihan Kota Mataram, Mataram, NTB. , 2002, Mataram dalam Angka 2002, BPS Mataram, Mataram, NTB. , 2002, Petunjuk Pengelolaan Persampahan, Dinas Kebersihan Kota Mataram, Mataram, NTB. Anonymous , 2005, Waste Technology lecture 3, http://www.scu.edu.au/staff_pages/mculle n/wt_lec3.html Achmad, Rukaesih., 2004, Kimia Lingkungan, Andi Offset, Yogyakarta. Apriadji, W. Harry., 1995, Memproses Sampah, Penebar Swadaya, Jakarta. Budiman, 2005, Mengelola Sampah Tak Perlu Teknologi Mahal, www.bppt.go.id/berita/news2php?id=698 Eddy dan Budi., 1990, Teknik Pembakaran Dasar dan Bahan Bakar, Jurusan Teknik Mesin, Fakultas Teknologi Industri -ITS, Surabaya. Hadiwiyoto, Soewedo., 1983, Penanganan dan Pemanfaatan Sampah, Yayasan Idayu, Jakarta. Henry, J Glynn., 1989, Environmental Science and Engineering, Prentice Hall, Engle Wood, Cliffs, New Jersey. INFIC., 1997, International Feed Data Bank System, Publication No. 3 Nebraska, USA Jupri, Ahmad., 2001, Manajemen Sampah Padat (Solid Waste Management), Jurnal Biologi Tropis Vol. 2 No. 1, Program 12

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 Studi Pendidikan Biologi PMIPA FKIP, Universitas Mataram, NTB M. M. El-Wakil., 1992, Instalasi Pembangkit Daya Jilid 1, Erlangga, Jakarta. Sitompul, Darwin., 1989, Prinsip-Prinsip Konversi Energi, Erlangga Jakarta. Tanudi dan Sukardi, Eddi., 1998, Membuat Bahan Bangunan dari Sampah, Puspa Swara. Wiradarma, 2002, The Energy Potency of Municipal Solid Waste to Supply Electricity in Mataram Regency, Rekayasa Vol. 3 No. 1, Fakultas Teknik, Universitas Mataram, NTB.

Green logs Evergreen shrubs Flowering plants Wood and bark

16770 25930 16120 38020 22590 18870 15970 14790

18120 26230 17320 38090 22640 19240 17720 15640

Household wastes Leather shoe Rubber Upholstery Polystyrene PVC Linoleum Rags Vacuum cleaner dirt Source: Paul T Williams (1998)

APPENDICES Table I. Calorific value of town wastes Component As Dry received (kJ/kg) (kJ/kg) Paper/paper product Paper mixed 15750 17530 Newsprint 18550 19720 Corrugated 16380 17280 boxes 17070 17910 Plastic coated 26350 27290 paper 14160 14830 Waxed milk cartons Junk mail 4170 19230 17730 28940 Food /Garden 38300 38300 Wastes Vegetable food 4760 19250 waste 18490 20540 Meat scraps 4870 9740 (cooked) 6270 20230 Fried fats 8560 18580 Lawn grass 19570 19940 Leaves

Adiabatic Oxygen Bomb Calorimeter Specification: 1. Thermometer 19 – 35 oC 2. Thermometer bracket 3. Thermometer support washer 13

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 4. Thermometer reading lens 5. Thermometer support rod 6. Motor assembly with pulley 7. Motor pulley 8. Stirrer drive belt 9. Stirrer pulley 10. Stirrer bearing assembly 11. Ignition wire 12. Stirrer shaft with propeller 13. Oval bucket 14. Bomb body cover/blanket. 15. Oxygen combustion bomb Ohaus weight scale

Samples Oven

Kongok disposal place

14

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