煤气化炉渣是煤气化过程中产生的固体废弃物。大量的炉渣堆积不仅造成了资源的浪费,而且增加了企业的运营成本,对当地环境造成危害。以内蒙古地区的煤气化炉渣为主要原料,加入水泥、生石灰、CaSO₄等,通过免烧结的方式制备陶粒。在制气炉渣、水泥、生石灰、CaSO₄质量比为70∶30∶2.5∶5的条件下制得的陶粒性能最优越,比表面积可达51.7 m²/g,堆积密度为809 kg/m³,颗粒破碎强度为6.61 MPa。将该陶粒用作反硝化生物滤池填料,相比于普通市售陶粒挂膜速度更快;在水力停留时间(HRT)为12 h时,化学需氧量(COD)由300 mg/L下降至60 mg/L以下,COD去除率在80%以上;硝态氮(NO₃^--N)由 60 mg/L下降至2 mg/L以下,NO₃^--N去除率在95%以上。利用煤气化炉渣制备免烧结陶粒实现了煤气化炉渣的资源化利用,同时为污水反硝化处理提供了一种新的填料。

Coal gasification slag is a solid waste generated during the coal gasification process.Coal gasification slag generated in Inner Mongolia region,China is mixed with cement,quicklime and CaSO₄ to prepare ceramsite through a non-sintering method.Result shows that the optimal raw materials mass ratio is coal gasification slag∶cement∶quicklime∶CaSO₄=70∶30∶2.5∶5.Specific surface area of non-sintered ceramsite prepared under this ratio can reach 51.7 m²·g^-1,bulk density is 809 kg·m^-3,and particle crushing strength is 6.61 MPa.Using this ceramsite as a filler for denitrification biofilters results in a faster biofilm formation rate than using ordinary commercially available ceramsite.Chemical oxygen demand (COD) decreases from 300 mg·L^-1 to below 60 mg·L^-1,with a removal rate over 80% when the prepared ceramsite is used as fillers for denitrification biofilters and the hydraulic retention time (HRT) is 12 h.The content of nitrate nitrogen (NO₃^--N) decreases from 60 mg·L^-1 to below 2 mg·L^-1,with a removal rate over 95%.This routine achieves re-utilization of coal gasification slag and provides a new filler for wastewater denitrification treatment.

张祎旸(1992-),女,博士,工程师,研究方向为污水处理,zhangyy.bjhy@sinopec.com;武陈(1985-),男,博士,高级工程师,研究方向为污水处理,通讯联系人,wuchen.bjhy@sinopec.com。