The main factors that control Value in Use for different end uses are:
- Power generation- $ per Giga Joule of useable energy ($/GJ), where the useable energy is
normally determined on a net basis ( gross calorific value less energy loss due to evaporation
of the as-fired moisture and water formed in combustion) subject to the constraints:
- Coking- $/ % net Carbon.Blending of coking and semi-soft coking coals is extensively carried
out to maximise the coke yield, coke strength and minimise costs. The coke yield from the
coke oven is dependent on the volatile matter of the coal blend whereas the coke strength is
strongly influence by the plasticity on the component coals.
- PCI- Replacement Ratio is the amount of coke replaced by the injection of coal into the base
of a blast furnace.