bomb & BOYS s gas calorimeter numerical with solution

 NUMERICALS: BOMB & BOY’s Gas Calorimeter

 1] 0.84 gm. of fuel on complete combustion in BOMB calorimeter increased the temperature of water in the calorimeter from 14.390C to 18.120C. The mass of water in calorimeter was found to be 1350 gm. and water equivalent of calorimeter is 135gm, calculate GCV and NCV of the fuel in J/gm. if it contains 9% hydrogen and latent heat of steam is 590cal/gm. [Ans.: GCV=27609.53 J/gm. , NCV= 25608.558 J/gm.] 

2] Following observations were recorded in the BOMB calorimeter experiment, Weight of coal used =0.9 gm., Wt. of water in calorimeter= 2500gm., Water equivalent of calorimeter= 440gm., Rise in temperature= 2.40C , Fuse wire correction= 10 cal., Cooling correction= 0.0520C. Calculate GCV and NCV of coal if contains 8% hydrogen and latent heat of steam is equal to 600cal/gm. [Ans.: GCV= 7998.755 cal/gm, NCV= 7566.755cal/gm]

 3] 1.2 gm. A coal sample containing 6% hydrogen on complete combustion in BOMB calorimeter gave following results, Wt. of water in calorimeter= 2000gm., Water equivalent of calorimeter = 500gm., initial temperature of water= 24. 50C , final temperature of water= 26. 20C, Fuse wire correction= 12 cal., Cooling correction= 0.040C, Acid correction = 55 cal. If latent heat of steam is equal to 580 cal/gm. Calculate GCV & NCV of coal sample. [Ans.: GCV=3569.167 cal/gm, NCV=3255.967cal/gm]

 4] The following observations were noted for gaseous fuel samples in Boy’s gas calorimeter experiment, Volume of gas burnt of STP= 0.08 m3, Mass of water circulated=30kg. , Rise in temperature of water= 8.20C, Mass of steam condensed= 0.04kg, Calculate GCV and NCV of the gaseous fuel sample. [Ans.: GCV=3075 kcal/m3, NCV= 2781.5 kcal/m3] 

5] The following data was obtained in Boy’s gas calorimeter experiment: Volume of gas burnt of STP= 0.1 m3, Mass of water circulated= 28 kg. , inlet temperature of water= 24.20C , outlet temperature of water= 32.40C Mass of steam condensed= 0.05kg, Calculate GCV and NCV of the gaseous fuel sample. [Ans.: GCV=2296kcal/m3, NCV=2002.5 kcal/m3]

 6] The following data was obtained in Boy’s gas calorimeter experiment: Volume of gas burnt of STP= 0.25 m3, Mass of water circulated= 25 kg. , inlet temperature of water= 25.40C , outlet temperature of water= 36.40C Mass of steam condensed= 0.056kg, Calculate GCV and NCV of the gaseous fuel sample. [Ans.: GCV=1100 kcal/m3, NCV=968.51kcal/m3]

 7] 0.7 gm. Of coal sample containing 5% hydrogen on complete combustion in BOMB calorimeter gave following results, Wt. of water in calorimeter= 2200gm., Water equivalent of calorimeter = 750gm, Rise in temperature= 2.620C , Fuse wire correction= 11 cal., Cooling correction= 0.020C, Acid correction = 55 cal. Calculate GCV & NCV of coal sample. [Ans.: GCV= 11031.43 cal/gm, NCV=10767.28 cal/gm] 

8] The following observations were noted for gaseous fuel samples in Boy’s gas calorimeter experiment, Volume of gas burnt of STP= 0.095 m3, Mass of watercirculated=32kg. , Rise in temperature of water= 11.40C, Mass of steam condensed= 0.045kg, Calculate GCV and NCV of the gaseous fuel sample in KJ/m3. [Ans.: GCV=16078.08 KJ/m3, NCV=14913.87 KJ/m3]

  NUMERICALS: Proximate Analysis of Coal 

1] 1.564 gm. The coal sample after heating in silica crucible at 1100C for 1 hour weighed 1.502 gm. The crucible is then covered with a vented lid and strongly heated further at 9500Cfor exactly 7 min. The coal on cooling weighed 1.1 gm. The crucible is further heated without a lid at 7250C for 30 min. The residue weighed 0.224 gm. Calculate Proximate analysis result. [Ans.: Moisture%= 3.96, V.M. %= 25.7, Ash%= 14.32, Fixed carbon%= 56.02]

 2] 1.24 gm. Coal sample when subjected to proximate analysis following observations were recorded, Wt. of coal after heating at 1100C (1Hr) = 1.21 gm. Wt. of coal after heating at 9500C (7min) = 1.05 gm. Wt. of residue after heating at 7250C (1/2Hr) = 0.135 gm. Calculate fixed carbon percentage in coal sample. [Ans.: Fixed carbon % = 73.81] 

3] 1.65 gm. The coal sample after heating in silica crucible at 1100C for 1 hour weighed 1.62 gm. The crucible is then covered with a vented lid and strongly heated further at 9500Cfor exactly 7 min. The coal on cooling weighed 0.768 gm. The crucible is further heated without a lid at 7250C for 30 min. The residue weighed 0.224 gm. Fixed carbon percentage in coal sample. [Ans.: Fixed carbon % = 86.37] 

4] 1.37 gm. Coal sample when subjected to proximate analysis following observations were recorded, Wt. of coal after heating at 1100C (1Hr) =1.29 gm. Wt. of coal after heating at 9500C (7min) =1.05 gm. Wt. of residue after heating at 7250C (1/2Hr) =0.15 gm. Calculate proximate analysis result. [Ans.: Moisture%= 5.83, V.M. %=17.51, Ash%= 10.94, Fixed carbon%=65.72] 

5] Analyse following two coal sample and which coal sample is of good quality? Justify. Test Coal sample 1 Coal sample 2 Wt. of coal 1.52 gm. 1.49 gm. Wt. of coal after heating at 1100C (1Hr) 1.48 gm. 1.45 gm. Wt. of coal after heating at 9500C (7min) 1.31 gm. 1.36 gm. Wt. of residue after heating at 7250C (1/2Hr) 0.172 gm. 0.212 gm

.Numericals on Ultimate Analysis of coal:

 1. Following observations were obtained in Ultimate analysis of coal a] 2.5 gm coal is burnt in the combustion chamber, the gaseous product after passing through Anhy. CaCl2 tube increased the weight of CaCl2 by 0.85 gm and increased the weight of KOH tube by 8.25 gm. b] 0.95 gm coal in Kjeldahl's experiment released NH3 which when passed in 50ml of 0.15 N HCl required 39 ml of 0.15 N NaOH (if blank reading for same Hcl & NaOH is 49.5 ml) c] Washings of bomb pot when 1.65 gm coal is combusted in BOMB calorimeter, on treatment with BaCl2 solution formed 0.325 gm BaSO4 dry. Calculate% of C,H,N,S and if G.C.V. of coal is 8245 kcal/kg calculate N.C.V. [% C = 90, % H= 3.78, % N =2.32, %S= 2.7].

 2. 0.12 g of coal sample on burning in combustion chamber in current of pure O2 was found to increase the weight of CaCl2 U-tube by 0.09 gm and KOH U-tube by 0.35 gm.Find the % C and % H in the coal. [C= 79.545 % , H =8.33%].

 3. 2.1 gm of coal sample in Kjeldahl expt. liberated ammonia which was absorbed in 40 ml sulphuric acid.The resultant solution required 17 ml of 0.1 N NaOH for complete neutralisation of H2SO4 in back titration.The blank titration reading was 28 ml.Find % N in coal.[0.733%]. 

4. 0.25 gm of coal sample was burnt in a stream of oxygen in a combustion tube.Increase in Mg-perchlorate tube was found to be 0.030 gm and that of lime soda tube 0.5 gm after combustion.Find % C and H of coal sample.[C=54.55%, H= 1.33%].

 5. 0.4 gm of coal sample was used in a bomb calorimeter to get GCV =8592 cal/gm.The ash obtained is extracted with acid and fluxed with barium nitrate to get ppt. of BaSO4.After drying the ppt weighed to be 0.05 gm.Calculate % S in coal and NCV if hydrogen in sample is 2%.[1.72 %, NCV =8486 cal/gm]

 6. One gram of coal sample was burnt in oxygen.CO2 was absorbed in KOH and water Vapour in CaCl2.The increase in weight of KOH and CaCl2 U-tubes is 3.157 and 0.504 gm respectively.Determine % C and % H in the sample.Comment on the quality of the coal.[C=86.1%, H =5.6%].

 7. Calculate the % C,H,N,S from the following observations for a coal sample. (i) 2.05 gm of the coal is burnt in combustion tube apparatus.The increase in the weight of CaCl2 U-tube is 0.55 gm and increase in weight of KOH U-tube is 5.75 gm. (ii) 0.75 gm of coal in Kjeldahl expt. released NH3, which is passed in 50 ml of 0.12 gm N HCl.The HCl requires 41 ml of 0.12 N NaOH to neutralize in back titration. (iii) Washings in bomb pot when 1.

8 gm of coal sample in bomb calorimeter is treated with BaCl2 solution to give 0.31 gm BaSO4. [ C= 76.50%,H= 2.98, % N = 2.016,% S= 2.36]. 8. Calculate the % S in coal sample when 2.5 gm is combusted in a bomb calorimeter. The washings on treatment with BaCl2 solution formed 0.222 gm BaSO4 ppt. [S=1.21 %].………………………………………………………………………………………… ………………………………………