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Show vi" V) o -J WLL -J LL £Xl W 3.0~--~----~----~--~----~----~--~ B&W DRY.ASM-REMOVAL FURNACE VOLATILE IN DRY ASH-FREE COAL. % 2.0~~~~--~~--~----~-----4-----+----~ t:; ~ 20 ::>0 £Xl 1.0 1~~=-~-;-;;;;.;;::::;t;:=;;;;;1iiiiiii130--~=--+----1 ~ 40~----r---1 o 48-~--+----' °5~--1~0 ----I~~ ---2-0 ~--~25- ---3~0 ---3-5 ~--~40 FURNACE LIBERATION, 1000 BTU/CU FT, HR 2.5,---------- FINENESS, % THRU en ~ 65 200 MESH ~O 66 ~ 0 1.5 ~--'67~=--~~~--I z < 68~ __ ~;:::::: u: LL 70t----..... - ----8730~l-.------~t---- O.5'-=~----1.----1 20 30 40 50 VOLATILE, IN DRY ASH-FREE COAL, % 2.0 r---~.._-_ o ~_-,L-_-" o 20 40 EXCESS AIR AT BURNERS, % Figure 6. Figures from "Steam/lts Generation and Use," 37th edition, by the Babcock & Wilcox Company, New York, 1963, page 17-21. The curves give the furnace liberation, volatile matter, particle size, and excess air dependence of the fraction of heat input lost as unburned char from Babcock & Wilcox dry-ash-removal pulverized coal-fired furnaces. The procedure is to locate the volatile matter content curve for the coal of interest, read the base loss at the appropriate furnace liberation, and mUltiply the result by factors obtained from the two lower curves, adjusting the base loss for effects of grind and excess air. 10 |