AN ENGINEERING METHOD FOR CALCULATION OF BOTH THEORETICAL COKE RATE AND EFFECTS OF DIFFERENT FACTORS ON COKE RATE

Theoretical coke rate means the necessary amount of coke to satisfy the thermal and chemical requirements under given conditions of raw materials, blast temperature, etc. The newly proposed method is characterized by combination of material and heat balance into one equation, and by that, the only thermal income is the heat of combustion before the tuyere with subtraction of heat carried away by the hot top gas. With this thermal balance, the necessary tuyere carbon is found. By adding to this carbon the solution carbon in pig iron and direct reduction carbon, the total carbon is finally obtained.By partial differentiation, a convenient and practically accurate method is derived for calculating effects of different factors on coke rate. Calculations for some Chinese and Japanese blast furnaces are given to show how this method might be used to examine operational efficiency, to calculate effects on coke rate of new technology like fuel injections through tuyere, and used for design purposes. Comparisons of this method with others like that of Runm and Pavlov are briefly given.