Research on coking process of coking-coal blended with plastic and sulfur sorbent
焦煤中添加废塑料和脱硫剂的焦化过程研究

Under the simulated conditions of coking chamber, the coking process of coking coal blended with plastic and sulphur sorbent was investigated. The H_2S removal efficiency of coking oven gas (COG) and the contents of residues of sulphur and zinc in the coke were also analyzed. The experimental results indicate that for the coking process of coking coal blended with ZnO, Fe_2O_3 or metallurgical dusts (MD), the removal efficiency of H_2S in COG was satisfying when the molar ratio of sorbent (ZnO and/or Fe_2O_3) to the volatile sulfur in the mixture of coal and plastic (n_(Zn+Fe)/n_S) is 1.2. The desulfurization activity of MD is relatively lower than that of ZnO and Fe_2O_3. Because of the thermal cracking behavior and chemical composition of plastic, the coke yield decreases from 81.5% for the coking-coal to 77.61% for the coking-coal with 5% of plastic added. However, if 5% of plastic and ZnO are added into the coking-coal, a satisfying removal effect of H_2S in COG can be obtained when n_(Zn+Fe)/n_S is increased to 1.7 due to the relative higher sulphur content in the plastic, while the contents of sulphur and zinc in the coke increase to some extent.