煤沥青是焦粉成型最有效的粘结剂,为了提高型焦强度,采用配加添加剂和细化沥青来强化煤沥青粘结性能,同时对强化机理进行分析。研究结果表明:助剂BJ可显著强化煤沥青的粘结性能,使型焦湿块和炭化块强度均明显提高;添加BJ后的煤沥青由固体颗粒态转变为粘稠的胶体态,粘结方式由以固相粘结为主变为以液相粘结为主;对煤沥青进行细磨处理可降低煤沥青热挥发产生的大孔洞数量;与煤沥青共混共磨的超细磨焦粉可填充煤沥青热处理产生的孔隙,与煤沥青共炭化而强化煤沥青的炭化骨架;当煤沥青粒度细磨至粒度小于0.15 mm时,配加质量分数为2.0%的BJ和12%平均粒度为8.6μm的焦粉可显著强化煤沥青粘结性能,大幅度地提高型焦强度。
Coal tar pitch is the most effective binder for the production metallurgical formed coke. In order to improve the strength of the briquettes, the additives of BJ and ultra-fine coke and the pitch refining were adopted to intensify the pitch cohesiveness. Moreover, the intensified mechanism was analyzed. The results show that BJ can intensify the cohesiveness of the pitch and make the strength of the wet briquettes, and the carbonized briquettes significantly improve. After added BJ, the state of the pitch changes from solid particle to colloid and the bond mode transforms from solid phase to liquid phase, which indicates the pitch adheres around the coke particles and bonds them to a firm briquette. The pitch refining reduces the large holes of the briquettes. And after co-grinding, the ultra-fine cokes fill the pores produced by heat volatilization of the pitch and carbonize with the pitch to intensify the carbonized skeleton. When co-grinded 12% coke with average diameter of 8.6 μm and 2.0% BJ are added in the pitch, the cohesiveness of the pitch is intensified and the strength is improved after refined the pitch to less than 0.15 mm.