煤焦油全馏分萃取预处理及副产物利用研究

STUDY ON EXTRACTION PRETREATMENT OF FULL DISTILLATE OF COAL TAR AND UTILIZATION OF BY-PRODUCT

以研究煤焦油改质工艺开发与应用为目标,选择由甲苯和正庚烷组成的二元混合溶剂对原料焦油进行改质处理,得到净焦油与煤沥青。结果表明,在甲苯/正庚烷质量比为0.5∶1、剂油质量比为1.5∶1、温度为70℃的条件下,对原料焦油进行萃取精制,焦油中灰分含量由1.89%降至0.03%,甲苯不溶物(TI)含量由9.56%降至0.31%,正庚烷不溶物(HI)含量由15.26%降至4.09%,残炭由4.07%降至0.39%,净焦油收率为83.2%。所得净焦油可尝试作为煤焦油全馏分加氢原料。同时,将副产物煤沥青与抚顺页岩油沥青按照不同质量比进行了掺混,试验发现,当煤沥青掺入量(w)为10%时,所得调合沥青的性能均达到重交通道路石油沥青AH-90标准,可用作重交通道路沥青。

The goal of this study was to develop a new processing method for coal tar modifica- tion. Coal tar was extracted by binary mixed solvents which consist of toluene and n-heptane. Purified tar and coal tar pitch were obtained in the process. The results indicate that the ash content of coal tar is decreased from 1.89% to 0.03G ,TI content is reduced from 9.56% to 0.31% ,HI content is lowered from 15.26G to 4. 09% ,and carbon residue is decreased from 4.07% to 0. 39% under the conditions of mass ratio of toluene to n-heptane of 0.5： 1, the mass ratio of binary extractant to coal tar 1.5 ： 1, and the ex- traction temperature 70 ℃. The yield of purified tar which can be used as hydrogenation feedstock is 83.2%. Meanwhile,the by-product,coal tar pitch,was investigated to be used as petroleum asphalt to prepare heavy traffic road pavement by mixing with shale oil pitch from Fushun. The study finds that when the content of coal tar pitch is 10% ,the performance of the mixed asphalt meets the quality standard of AH-90.