免烧法煤气化粗渣制备陶粒工艺及其性能研究

Research on preparation of non-sintered ceramsite from gasification cinder and its performance

为实现煤气化粗渣处置资源化、无害化利用,以煤气化粗渣为主要原料,采用改进后的免烧养护法制备9组不同配比的免烧煤气化粗渣陶粒,测试各组陶粒的堆积密度、筒压强度和吸水率,并进行性能优异度评价。根据结果筛选出进入浸出毒性测试的试验组,检测浸出液中铬、砷、镉、铅4种重金属含量,评价其环境安全性。结果表明:陶粒筒压强度均符合GB/T 17431.1—2010《轻集料及其试验方法第1部分:轻集料》的要求,其值为5.59～8.71 MPa;吸水率随煤气化粗渣含量增加而升高;陶粒性能优异度得分最高且符合环境安全标准的原料配比为煤气化粗渣掺加量73%,水泥投加量15%,石英砂投加量12%(均为质量分数);浸出毒性测试结果显示,免烧工艺对煤气化粗渣中重金属的固定化能力较高。

In order to realize the resource disposal and harmless utilization of gasification cinder,we took it as the main raw material,and nine sets of non-sintered ceramsites from gasification cinder with different proportions were prepared by the improved method of non-sintered curing.The stacking density,cylinder compressive strength and water absorption of each ceramsite were tested,the attained performance was evaluated.Accounting to the result of which,experimental groups that could enter the test of leaching toxicity were selected.With the detection of the contents of four kinds of heavy metals:Cr,As,Cd and Pb in the leaching solution,their environmental safety was evaluated.The results showed that the cylinder compressive strength of ceramsites all met the requirement of GB/T 17431.1-2010“Lightweight aggregates and its test methods-Part 1:Lightweight aggregates”,the value with the range of 5.59~8.71 MPa.And the water absorption increased with the increase of the content of gasification cinder in ceramsite.The best formula for preparing the ceramsite with the highest attained performance score and the conformity of environmental safety standards was gasification cinder 73%,cement 15%and quartz sand 12%(mass fractions).The results of leaching toxicity showed that non-sintered method posted high immobilization ability of heavy metals in gasification cinder.