this ppt inclides the method to find the calorific values of fuel by bomb calorimeter.

1.  Muhammad Awais (15103122-011)
&
 Asif Mehmood (15103122-012)
Presents

2. AND Method for Calculation of Calorific
values

3.  The amount of energy produced by the
complete combustion of a material or fuel. Measured
in units of energy per amount of material, e.g. kJ/kg.
 The amount of energy available from an item
of food when digested, mostly
from carbohydrates and fats.

4.  The fluid can be looked upon as a source of energy
because of its high calorific value. The biogas from the
digester has a calorific value of 4,500 to 5,000 K.
cal/m³, and can be burnt in the boiler for raising steam.
 The calorific value of a substance is a measure of its
heating power, which depends on the composition of
the substance being burned.

5.  Calorific Value (CV) is a 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.
 The CV of gas, which is dry, gross and measured at
standard conditions of temperature (15o
C) and
pressure (1013.25 milli bars), is usually quoted in Mega
joules per cubic meters (MJ/m3
).
 Gas passing through the National Grid pipeline system
has a CV of 37.5 MJ/m3
to 43.0 MJ/m3
.

6.  Knowledge of the CV of natural gas is an essential part
of the day to day activities of National Grid as this
information is used to determine the amount of energy
transported by National Grid. CV information is
provided daily to gas shippers and suppliers, which is
then used to bill gas consumers. This data is also used
by National Grid to determine transportation charges
for gas shippers and suppliers.

7.  Lower calorific value of a fuel portion is defined as the
amount of heat evolved when a unit weight (or volume
in the case of gaseous fuels) of the fuel is completely
burnt and water vapor leaves with the combustion
products without being condensed.
 There are other names for lower calorific value (LCV),
which are:
 Net Calorific Value (NCV),
 Lower Heating Value (LHV).

8.  Higher calorific value of a fuel portion is defined as the
amount of heat evolved when a unit weight (or volume
in the case of gaseous fuels) of the fuel is completely
burnt and the products of combustion cooled to the
normal conditions (with water vapor condensed as a
result). The heat contained in the water vapor must be
recovered in the condensation process.
 Corresponding names for higher calorific value (HCV),
are:
 Gross Calorific Value (GCV),
 Higher Heating Value (HHV)

9.  The energy released when 1 gram of material is
combusted is called its fuel value

11.  Calorific value (CV) of a fuel is a characteristic of fuel
which is defined as the energy liberated per kg of fuel
burnt. Fuels are found in three phase i,e. solid, liquid
and gaseous. Junker's calorimeter is used to measure
the CV of gaseous fuels.

13.  It is used to measure the calorific value (CV) of solid as well as
liquid fuel. But to determine the CV of gas, one need to choose
Junker's calorimeter.
 A calorimeter contains thick walled cylindrical vessel and it
consists of the lid which supports two electrodes which are in
contact with fuse and fuel sample of known weight.
 The lid also contains oxygen inlet valve through which high-
pressure oxygen gas (at about 25 to 30 atm) is supplied.
 Entire lid with fuel sample is now held in a copper calorimeter
containing known weight of water. A mechanical stirrer is
provided to stirred well for uniform heating of water.
 A thermometer is also provided to measure the change in
temperature of water due to combustion of fuel in Lid

14.  A known quantity of fuel sample is added in the
crucible.
 Start the stirrer and note down the initial temperature
of water.
 Let the current pass through the crucible and let fuel
sample to burn in presence of oxygen.
 Heat released during combustion of fuel is taken by
water and hence temperature of water rises.
 Note final steady state temperature of water.

15.  Higher Calorific Value of fuel =
 (m1+m2) x (Tc + T1 - T2 ) x Cw / mf
 Where m1 and m2 are the mass of water in the copper
calorimeter and water equivalent of bomb calorimeter
respectively.
 mf is the mass of fuel sample whose calorific value is to be
determined.
 T1 and T2 are the final and initial temperature of the water
sample. Tc is temperature correction for radiation losses.
 Cw is specific heat of water

16.  Bomb Calorimeter is used for the measurement of the
calorific value of fuel oils, gasoline or petrol, coke, coal,
combustion waste, foodstuffs and building materials
etc.
 A bomb calorimeter is also used for energy balance
study in ecology and study of Nano-material, ceramics,
zeolite. The bomb calorimeter is helpful to study the
thermodynamics of common combustible materials.

17. So that’s all about calorific values
Thank you