The gradation of non-coking coal is based on Useful Heat Value (UHV), the gradation of coking coal is based on ash content and for semi coking / weakly coking coal it is based on ash plus moisture content , as in vogue as per notification.
What is the difference between GCV and UHV of coal?
In GCV( Gross calorific Value) it is asumed that moisture & other elements present in coal(besides coal) can be used for generation of Heat and hence ‘ gross’. While in UHV( useful heat value) it is assumed that those elements cant produce heat and so are eleminated for the purpose of heat calculation.
What is washery grade coal?
Washery Grade -VI. Exceeding 42% but not exceeding 49% Grades of Semi-coking and Weakly Coking Coal. Grade. Ash+Moisture.
How is coal GCV calculated?
GCV= 7115.197 – 123.971*M – 81.3121*A + 20.7421*FC, Where GCV in kcal/kg and moisture, ash, fixed carbon in air dried percentage basis.
What is the relation between GCV and NCV?
Net Calorific Value (NCV) also known as lower heating value (LHV) or lower calorific value (LCV) is determined by the subtracting the heat of vaporization of the water vapour from the higher heating value. This treats any H20 formed as a vapor. Natural gas prices are decided on the basis of GCV and NCV.
What is heating value of coal?
The calorific value of coal is measured for almost all coal samples. Calorific value is a measure of the amount of energy produced from a unit weight of coal when it is combusted in oxygen. …
How many grades of coal are there?
What are the 4 grades of coal?
Coal is classified into four main types, or ranks: anthracite, bituminous, subbituminous, and lignite.
Why coal is washed?
In addition to the coal itself, pieces of rock, sand and various materials are contained in the mixture. Thus, before coal can be sold to consumers, it must be cleaned. … Washing coal increases its efficiency and quality, therefore increasing its price. Coal washing can also help to reduce emissions from burning.
Which grade of coal is used in thermal power plant?
Lignite is used in thermal power stations since it is of lower grade and contains less percentage of carbon. How satisfied are you with the answer?
How do you calculate coal?
Since coal has a heat value of 20,000 kJ/kg, for producing one kw.hr we require (10765 / 20000) 0.538 kg of coal. This translates to (0.538 x 100 x 1,000) 53800 kg/hr (53.8 T/hr) of coal for an output of 100 MW.
How can you tell the quality of coal?
Due to the fact that coal is typically used as fuel the calorific value is ideal to give a first impression of the product quality. For a first (“proximate”) analysis of coal, the calorific value, ash, moisture, and volatile content are measured. Based on these data the so-called fixed carbon content is calculated.
What is VM in coal?
Volatile matter is one of the most common parameters measured in coal. … It is measured as the weight percent of gas (emissions) from a coal sample that is released during heating to 950 C° in an oxygen-free environment , except for moisture (which will evaporate as water vapor), at a standardized temperature.
Why NCV is less than GCV?
Answer: This is because,NCV (net calorific value) is the quantity of heat produced by combustion when the water produced by combustion remains gaseous. Since water releases heat when it condenses, GCV is clearly bigger than NCV.
How do you convert NCV to GCV?
Calculate a) Gross calorific value, moist basis b) Net calorific value, dry basis c) Net calorific value, moist basis d) Gross calorific value, dry basis using Dulong formula. = 32060.2 KJ/Kg NCV = GCV – 24.44(9×%H + %M) = 30630.26 KJ/Kg Thus NCV = 0.955 times GCV in this case.
What is HCV and LCV?
A LCV is defined in the Motor Vehicles Act as a vehicle with GVW of not more than 6 ton. A HCV is defined as vehicle with GVW of more than 6 ton. Gross vehicle weight is defined as vehicle weight plus rated payload. Rated payload is the maximum weight permitted to be loaded on the vehicle under Motor Vehicle Act.