Showing posts from August, 2018

calorific value/calorific value of coal

CALORIFIC VALUE/ calorific value of coalcalorific value GCV NCV It is defined as the total amount of heat librated when a unit mass of a fuel is burnt completely. Solid/liquid : cal/g or kcal/kg Gaseous : cal/cm^3 or kcal/m^3 CALORIE:- It is defined as the total amount of heat required to raise the temperature of 1grams of water through 1 digree centigrate.
GROSS AND NET CALORIFIC VALUE(GCV and NCV):-GROSS CALORIFIC VALUE(GCV):-It is the total amount of heat generateed when a unit quantity of fuel is completely burn in oxygen and the product of cumbustion are cooled down to the room temperature.
calorific value of coal It is alseo called as “higher calrorific value” (HCV) *HCV is determaine by bomb calorimeter.
NET CALORIFIC VALUE (NCV):-It is defined as the net heat produced when a unit quantity of fuel is completely burnt & the product of combustion are allowed to escape. It is also called as “lower calorific value”(LCV) LCV=HCV – Latent heat of water vapour LCV= HCV- Weight of hydogen × 9×la…


casting is the one of the oldest manufacturing processes,and is one of the first step in manufacturing most products. in this process material is first liquified by the properly heating in its suitable furnace and is then poured into a
 previously prepared mould cavity trimmed and cleaned to shape.the following need to be explored for casting process
1- preperation of moulds and pattern
2-melting and pouring of liquified matel
3-solidification and further cooling at room temperature
4-defects and inspection.

although there are several process assocaited with the casting process the following common
features are valid for the various casting process in the context of the four areas just mentioned.
1-the melting temperature of the job and the mould material
2- the solublity of and the chemical reaction between the job and mould material
3- the solublity of the atmosphere in the material at different temperatures to be encountered in the casting operation
4- the thermal properti…

what is fuel ?
INTRODUCTIONOF FUEL:- Any combustible substance which on burning in presence of oxyzen produce large amount of heatthat can be used for domestic and industrial purposes is called fuel. Example:-wood,charcoal, coal, kerosene etc. During cumbustion of fuels, a chemical reaction involving breakdown of bond of reactants and formation of new bond in the products and this results in large amount of heat release, therefore they are called as chamical fuel. CLASSIFICATION OF CHEMICAL FUELS:- 1.-PRIMARY FUEL I.Solid fuel(wood)
II.Liquide fuel( crude oil) III.GAS(natural gas)
2:-SECONDARY FUEL I.Solid(coke) II.Liquide(LPG) III.Gas(water gas)

Ualso visit - Https://  instagam-