What is caking property of coal?
Coal that softens and agglomerates on heating and after volatile matter has been driven off at high temperatures; produces a hard gray cellular mass of coke.
Why caking of coal is important?
This is a unique property of coals in the bituminous group of coals and is an essential property for coals which are required for coking. As a caking coal is heated it passes through a region where it becomes very plastic, softens, swells and then re solidifies. … The caking behaviour is critical to coke making.
What is G index of coal?
The value of G characterizes the content of active component of coal, and is considered as a measure of the degree of reduction of coal. The method using a plot of the volatile matter content (V, d.a.f.) vs. G can predict the coke strength and permits selection of the best economic coal blending ratios.
Is coke obtained from coal?
Coke is produced by heating coal at high temperatures, for long periods of time. This heating is called “thermal distillation” or “pyrolysis.” In order to produce coke that will be used in blast furnaces, coal is usually thermally distilled for 15 to 18 hours, but the process can take up to 36 hours.
What is rank of coal?
Coal is classified into four main types, or ranks: anthracite, bituminous, subbituminous, and lignite. The ranking depends on the types and amounts of carbon the coal contains and on the amount of heat energy the coal can produce.
What is M40 in coke?
The resistance, in Micum drum, is an international standardized method, being the most used one, indices obtained in the test are: M40= mechanical resistance M10 = abrasion For a high quality coke these indices must have values between M40= 80 ÷ 85% and M10 = 5 ÷ 7%.
What is CSR and CRI of coke?
Coke reactivity to carbon dioxide (CRI) determines percent weight loss of coke, as a result of carbon dioxide action on the coke sample in temperature 1100°C. The coke strength after reaction (CSR) determines >10 mm grain amount yield obtained after mechanical tumbling of coke after reaction with carbon dioxide.
What is difference between coking coal and non coking coal?
A non-caking coal is that coal which on heating in absence of air doesn’t from a coherent mass of residue. … A coking coal is that coal which on heating in absence of air leaves a solid residue. A non-coking coal also leaves a solid coherent residue which may not possess the physical & chemical properties of the coke.