Question

chacteristics of lignite
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Answer 1

Answer:

Lignite has low levels of sulfur (less than 1%) and ash (approximately 4%), but it has high levels of volatile matter (32% and higher by weight) and produces high levels of air pollution emissions.

Answer 2

$\huge\underline\mathfrak\red{Answer:}$

• Lignite is brownish-black in color and has a carbon content around 70%, a high moisture content sometimes as high as 75 %, and an ash content ranging from 5-19% compared with 7-12% for bituminous coal.
• The energy content of lignite ranges from 10 to 20 MJ/kg on a moist, mineral-matter-free basis. The energy content of lignite consumed in the United States averages 15 MJ/kg, on the as-received basis (that is, containing both inherent moisture and mineral matter). The energy content of lignite consumed in Victoria, Australia, averages 8.4 MJ/kg

• Lignite has a high content of volatile matter which makes it easier to convert into gas and liquid petroleum products than higher-ranking coals.
• Unfortunately, its high moisture content and susceptibility to spontaneous combustion can cause problems in transportation and storage. It is now known that efficient processes which remove latent moisture locked within the structure of brown coal will relegate the risk of spontaneous combustion to the same level as black coal, transform the calorific value of brown coal to a black coal equivalent fuel, and significantly reduce the emissions profile of 'densified' brown coal to a level similar to or better than most black coals.
• However, removing the moisture increases the cost of the final lignite fuel.