Study Of Coking Coal Thermal Separation With Roller Screen And Its Influence On Coke Quality

In order to make coking coal dried and classified, this paper presents a thermal separation process. In this process, with the introduction of hot exhaust, wet coal is dried and graded by the roller screen. After the resulting fine part is thermoformed, type balls are sent into the furnace coke with the coarse fraction together. This paper experimentally determines the optimal operation parameters of the heat sorter-roller screen, and proceeds to coke through the thermal separation process to compare with other coking process for the practicability of this technology.Firstly, the optimum conditions for the roller screen are determined by changing the process parameters. The results shows that: the factors which influence the thermal separation device efficiency are wet coal feeding rate, hot exhaust temperature, the moisture content of the wet coal, roller screen speed, roller screen inclination and so on. Under the experimental conditions of the thermal separation device runs its optimum operation at the feed amount 18Kg/h, wet coal moisture content of 10%, the hot exhaust gas temperature 300℃, speed 8r/min and the inclination of 8°. With the increase of wet coal feed rate and the moisture content of wet coal, Tianhe 1/3 coking coal, Jiexiu coking coal and Zhongwei lean coal’s classification efficiency decrease; with the hot exhaust temperature rising the classification efficiency gradually increase; in a certain roller screen speed range, with an increase in speed the classification efficiency comes to decrease after its initial increase; in a certain roller screen inclination range, as the angle increases, the classification efficiency decreases; coal material residence time is related to roller screen’s inclination and speed. Secondly, under the optimum operating conditions for the device coking material is subjected to thermal separation process and coked. By comparison with conventional coking of coal blending, briquette coal coking process and coking coal preheating process, the following conclusions come: Compared with conventional coking coal blending, thermal separation process plays a role in improving coke quality. MIS increased by 4.5% ~ 7.3%, SS increased by 11% to 18%; CRI decreased from 1.2% to 6.6%, CSR increased by 10% to 17%; Compared with the briquette coal coking process and coking coal preheating process, the coking coal thermal separation process still shows a good process property. When used with Tianhe 1/3 coking coal and Zhongwei lean coal for 60 percent of the total, the thermal separation resulting coke quality compared to other pretreatment process or the quality is very slightly less; when used with Tianhe 1/3 coking coal and Zhongwei lean overall amount of 50%, the thermal separation resulting coke quality is superior to other pretreatment processes resulting coke quality.