Quality Comparison Between Coal Drying Of Low Temperature Low Pressure With High Pressure High Temperature Coal Jambi

Abstract

Coal Jambi (PT. CTSP) belongs to the low rank coal (lignite), which has total moisture of 47.05% with a calorific value of 3829 kcal / kg. Drying technology can lower water levels in the low rank coal that will improve the quality of coal. Coal drying can be done at low temperature low pressure (oven) and at high temperature high pressure (autoclave).
In the drying process with low temperature and low pressure, it is obtained an inherent moisture content in equilibrium after being placed in the open air for approximately 700 hours which are 15.88%, 12.00%, 12.70% and 6.53% for coal dried at 200â°C, 150â°C, 110â°C and 75â°C. While the inherent moisture content of raw coal is at 15.14%. A high temperature drying and high pressure (autoclave) can reduce the total water content of 47.05% to 3%. The inherent moisture content of less than 5% moisture is stable after its contact with the open air for 2000 hours. Based on the laboratorium experiments, it shows that the method of drying with low temperature and low pressure to the heating temperature 150â°C has a inherent moisture content approaching inherent moisture content of coal measured in water conditions dried basis (adb) is 12:00%, whereas with the method of the high temperature and high pressure, the coal produces moist moisture under humid water levels on water conditions dried basis (adb) which is about 3%. Based on the research data, the method using high temperature high pressure is better because it produces a stable dry coal with a moisture content of relatively small water about 3%, while the low-temperature low-pressure method to produce coal which has a moisture content above 10% moisture.