MATERIALS THAT ARE BURNED TO
value Bomb calorimeter
A bomb calorimeter is a device that is designed to measure th
amount of heat that is given off or taken in by a reaction.
It is designed to be isolated from the surroundings, meaning
no heat can leave or enter the device..
In order to accomplish this, the outside wall of the calorimeter
is a vacuum sealed wall similar to an insulated mug you might
carry coffee in. Inside the calorimeter is a vessel in which the
reaction occurs surrounded by a water bath. The temperature
the water bath can be monitored via thermometer.When a
reaction takes place in the calorimeter, the temperature of the
water bath changes. If an exothermic reaction occurs, the wate
bath temperature goes up. If an endothermic reaction occurs,
water bath temperature goes down.In an ideal calorimeter all t
heat exchange would take place with the water. However, in re
the materials from the calorimeter itself, the stainless steel, th
etc., exchange heat with the system as well. We can correct fo
using a heat capacity for the calorimeter in our calculations.Be
the heat is exchanged inside the calorimeter, we can set the t
value What is carbonisation?
Heating of coal in absence of air to produce coke is called
Types of carbonisation:-
• low temperature carbonization
• High temperature carbonisation.
Low temperature carbonisation(LTC):-
Heating of coal at temperature of 500-700℃ and the amount
of coke obtained is about75-80% of carbon and it contains
High temperature carbonisation:-
Heating of coal at temperature 900-1200℃ and the amount of
coke obtained is about 98% of carbon and it contains only 1-3%
value Synthetic petrol
Petroleum produced by synthetic processes instead of from the
natural (fossil) reserves
The Bergius process is a method of production of liquid hydrocarbons
for use as synthetic fuel by hydrogenation of high-volatile
bituminous coal at high temperature and pressure.
• The coal is finely ground and dried in a stream of hot gas.
The dry product is mixed with heavy oil recycled from the process.
A catalyst is typically added to the mixture.
• The whole is heated with hydrogen at 450®C and under
pressure 200-250 atm for about 1.5 hours,during which hydrogen
combines with coal to form saturated hydrocarbons.
• The issuing gases are led to condenser,where a liquid resembling
crude oil is obtained,which is then fractionated to get
1.gasoline,2.middle oil,3.heavy oil.
• The middle oil is hydrogenated in vapour phase in presense of a
solid catalyst to yield more gasoline.The yield of gasoline is about
60% of thr coal dust used.
Tropsch (FT) process, originally developed by Franz Fischer and Hans
Tropsch in early 1920s, is a series of chemical reactions that involve th
conversion of hydrogen and carbon monoxide into liquid
hydrocarbons by using a catalyst.
The FT process involves a catalytic chemical reaction in which
carbon monoxide (CO) and hydrogen (H2) present in the synthetic
gas are converted into hydrocarbons of different molecular weights
based on the following equation
The reactions involved in the FT process are highly exothermic
therefore, the elimination of heat is important when designing a
commercial reactor. Three types of reactors are generally used for
Slurry bed reactor
Fluidized bed reactor
Fixed bed reactor
value KNOCKINGKnocking is a sharp sounds caused by premature combustion of
part of the compressed air-fuel mixture in the cylinder.
In a properly functioning engine , the charge burns with the flame
front progressing smoothly from the point of ignition across the
combustion chamber .
1)Knocking is generally caused in an old engines .
2) Knocking is due to auto-ignition of fuel in the cylinder during
3)Knocking is mainly caused by the “ deposits of carbon” on the
walls of the cylinder.
4) One should be noted that carbon deposits absorb heat and it
won’t release it. And it made the fuel auto-ignited before the spark
5) When the fuel is auto-ignited before the spark plug, the fire from
below the TDC ( top dead centre) moves upwards and the spark from the spark
plug moves downwards , both coincides towards each other then it
causes the knocking
Moving bed reactors are reactors in which the catalytic material
flows along with the reactants and is then separated from the
exit stream and recycled.
Moving bed reactors are catalytic reactors in which the catalyst
moves through the reactor along with the reactants.
They are open systems and operate at steady state .
Moving bed reactors are frequently used in wastewater
treatment processes.They can be tuned to the application by
selecting specific microbes, but these types of reactors are
very effective at nitrification, denitrification, and chemical oxygen
demand (COD) reduction processes.
• Easy to regenerate catalyst
• Have plug flow characteristics
• Flow of solids not easy to maintain
• Poor heat transfer characteristics
octane number is a measure of the performance of a fuel.
cetane number is the measure of the
delay of the ignition of a fuel.
octane number is important for predicating the knocking of an engine.
octane number is given for gasoline.
cetane number is given for diseal.
cetane number is important for predicting the ignition of an engine.
It is the total quantity of heat liberated when a unit mass of fuel is
burn completely. It judge the efficiency of fuel. The quantity of heat
liberated can be measured in different units.
3.British thermal unit
1 BTU= 252 cal.
Types of calorific value:-
1. Gross calorific value:-
It is the amount of heat generated when a unit quantity of fuel
is completely burn in oxygen & the products of combustion are
cooled down upto room temperature.
2. Net calorific value:-
It is the amount of heat produced when a unit quantity
of fuel burnt is completely escape. It is also called as
Lower calorific value.