Coal Quality

Written by Administrator

Sunday, 30 August 2009 22:13

Coal is sediment organic which the quality is hardly determined by some factor for example place there is of hollow, age and the many contamination. In its use machine design utilizing coal as component of burning must correspond to quality of the coal that machine utilized durable. RECOGNITION of PUBLIC QUALITY OF COAL Coal is generating raw material energy utilized for industry. Quality of from coal would of vital importance in determining equipments utilized. To determine quality of coal, some things which must be paid attention is : High heating value (kcalkg), Total moisture (%), Inherent moisture (%), Volatile matter (%), Ash content (%), Sulfur content (%), Coal size (%), Hard grove grindability index (< 3mm, 40mm, 50mm), Fixed carbon (%), Phosphorus/chlorine (%), Ultimate analysis : (carbon, hydrogen, oxygen, nitrogen, sulfur, ash), ash fusion Einstein characteristic temperature. a. High Heating Value (HHV) High heating value hardly having an effect on to operation of equipment, like : pulverizes, coal pipe, wind box, burner. Excelsior high heating value hence coal stream every hour is increasingly low so that speed of coal feeder must be accommodated. b. Moisture Content Content moisture influences number of usages of the primary air, at coal with high moisture content will require primary air more to dry the coal at permanent mill exit temperature. c. Volatile Matter Volatile content matter influences perfection of combustion and flame intensity. perfection of Combustion determined by : Fuel Ratio = Fixed Carbon / Volatile Matter Excelsior fuel ratio hence carbon which is combustible not more and more. d. Ash Content and Composition Ash content will brought with combustion gas through combustion chamber and convection area in the form of fly ash or base ash. Around 20% in the form of elementary ash and 80% in the form of fly ash. Ash content excelsior and depends on the composition influencing level of defilement (fouling), abrasion and equipments corrosion passed by. e. Sulfur Content Sulfuric content had an effect on to level of cool side corrosion happened at element of air heater, especially if activity temperature lower than situation of sulfur dew, beside influential to dusty arrest effectiveness at equipments of electrostatic precipator. f. Coal Size Coal grain size limited at granule spread and harsh item. Softest item for measure < 3 mm, medium of harshest measure of 50 mm. softest item is limited dustiness and level of amenity controlled the flight of wind causing defiles area. Level of dustiness and amenity flies that there are still be determined also by content moisture coal. g. Hard grove Grindability Index (HGI) Capacities mill (pulverizes) designed at Hard grove grindability certain index, hence for lower HGI of the capacities lower than the measure value to yield the same fineness. h. Ash Fusion Characteristic Ash Fusion Characteristic will influence level of fouling, slagging and operation of blower. http://bestcoaltrading.blogspot.com

Last Updated on Sunday, 06 December 2009 18:51