METHOD FOR EVALUATING WEATHERING DEGREE OF COAL, METHOD FOR EVALUATING COKING PROPERTIES OF WEATHERED COAL, METHOD FOR CONTROLLING WEATHERING DEGREE OF COAL, AND METHOD FOR PRODUCING COKES

• Main Authors: SUMI, Hiroyuki, DOHI, Yusuke, ANYASHIKI, Takashi, FUKADA, Kiyoshi, FUJIMOTO, Hidekazu, SHIMOYAMA, Izumi
• Format: Patent
• Language: English; French; German
• Published: 06.10.2021
• Subjects: CHEMISTRY; DESTRUCTIVE DISTILLATION OF CARBONAGEOUS MATERIALS FORPRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS; FUELS; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; LUBRICANTS; MEASURING; METALLURGY; PEAT; PETROLEUM, GAS OR COKE INDUSTRIES; PHYSICS; TECHNICAL GASES CONTAINING CARBON MONOXIDE; TESTING

Provided are, by using an index with which the influence on the strength of coke can be evaluated, a method for evaluating a weathering degree of coal and a coking property of weathered coal within the ranges in which the weathering degree and coking property cannot be determined by using conventional methods, and a method for controlling the weathering degree of coal with which it is possible to add weathered coal to a coal blend to be used for producing coke without decreasing the strength of coke by using the index. The weathering degree of coal is evaluated by using the surface tension of semicoke which is prepared by performing a heat treatment on weathered coal as an index. Moreover, the surface tension of each brand of semicoke which is prepared by performing a heat treatment on each of the plural brands of coal included in coal stock is previously determined. In addition, the proportion of each brand of coal to the whole coal stock is also previously assessed. The weathering degree of each brand of coal is controlled so that the interfacial tension ³ inter of a semicoke blend which is prepared by blending the plural brands of semicoke in accordance with the proportions is 0.03 mN/m or lower.