Calorific Test of Gaseous Fuel

Calorific Test of Gaseous Fuel

Boys CalorimeterGroup 4Tito VilallunaData InterpreterAldwin ReantasoResearcherMico TanResearcherAnjo SantosData AnalysisEl king PosadasSubject/Topic Analysis

What is Calorific Value?

the measure of heating power and is dependent upon the composition of the gas. The CV refers to the amount of energy released when a known volume of gas is completely combusted under specified conditions.Specifically,Quantity of heat released during the complete combustion of one cubic meter of gas under normal temperature and pressure conditions (1.01325 bar or 101 325 Pascal at 0C) when the water formed during combustion remains as steam and the combustion products are evacuated under normalised test conditions.Combustion is the chemical reaction that occurs between a fuel and a combustion agent, for example oxygen in the air in the presence of a heat source. The result of complete combustion is essentially carbon dioxide (CO2), water (H2O) and heat.Boys CalorimeterMethodThe calorific value of a gaseous fuel can be found by burning the gas in a water cooledvessel under standard test conditions. The equipment used is the Boy's Calorimeter.ApparatusThe calorimeter consists of a water-cooled copper chimney set over a wooden basecontaining a central burner. This equipment may be used for the determination of the calorific value (CV) of anygaseous fuel provided that the correct burner nozzle is fitted. A known volume of gassample is metered and burned inside the chamber surrounded by a cooling coil, fedfrom a constant head apparatus with a known volume of water. The CV is calculatedfrom the rise in temperature of the water after making suitable corrections.ExperimentalThe Boys Calorimeter is set up prior to the laboratory beginning to allow the system to stabilise.

At the beginning of the experiment (e.g. starting point a 100 on the gas meter);1. Begin to collect water in the 2L measuring cylinder. At the same time push the25cm3 measuring cylinder under the spout at the base of the calorimeter (thevolume collected for the whole of the experiment must be recorded).

2. The water in the 2L measuring cylinder does not have to be retained, but the totalvolume over the whole of the experiment must be recorded.

3. At some point during the experiment a sample temperature of the water must betaken and recorded.

4. Note the Inlet temperature and record for every 2 revolutions till the end of theexperiment.5. Note the Outlet temperature and record for every revolution till the end of the experiment.

The experiment is carried out for a period of 8 revolutions

At the end of the experiment:Stop collecting water to the 2L measuring cylinders.Stop collecting water to the 25cm3measuring cylinder.Record effluent gas temperature.Record ambient temperature.Record barometric pressure.Gas Sample

Getting the CV of sample (Easy Way)

Getting the Calorific Value (Hard Way)CV (Rise in water temperature.) x (mass of water) Corrected volume of gas burnt = x specific heat of water =(Ti - To) x ' a' x V'wVg x 4.187 kJ / li (ie MJ / m3)= - = (37.23 15.00) x 1.033 x 7.62118.88 x 4.187 MJ/ m 38.81 MJ/ m 3 3This is the gross CV and has not included the inlet water temp. or the effluent gas corrections.Thus the gross C.V. of the gas is = 38.81 - 0.564 + 0.0643= 38.18 MJ/m3.The heat in the water produced from the hydrogen present in the gas is :vol. collected x Latent heat = 29.0 x 2.45 = 71.05 kJ.But gas vol. used = 0.01888 m3 therefore heat in water = 71.05/ 0.01888 = 3.76MJ/m3 and Nett .V. = 38.18 - 3.766 = 34.42 MJ/m3

Calorific Values of Gaseous Fuels