地质钻探废弃冲洗液固化处理技术研究及应用

Research and application of solidification treatment technology for waste drilling fluid in geological drilling

摘要:

在地质钻探废弃冲洗液无害化处理过程中，经固液分离后的废弃固相主要由大量磨细的岩粉和细砂构成，但含水率较高，还含有大量的有机物和重金属离子等有害物质。针对地质岩心钻探废弃固相的固化问题，首先从P.O42.5普通硅酸盐水泥、粉煤灰和石灰3种固化主剂中优选了水泥作为主剂，而后通过正交实验确定了固化剂基础配方为：25% P.O42.5普通硅酸盐水泥+2% PF-3型促凝剂+3% RES-1型复合早强剂，并通过极差分析进行了验证，然后进行了支撑剂加量的确定，7%支撑剂加量既能有效增加固化强度，又不会增加搅拌难度。最后将固化剂配方应用于YK11-2井废弃冲洗液处理野外试验中，固化后的固化体抗压强度达1.41 MPa，各项污染指标和重金属离子符合国家二级排放标准，取得了较好的处理效果。

Abstract:

In the process of harmless treatment of waste geological drilling fluid， the waste solid after solid-liquid separation contains a large amount of ground rock powder and fine sand with high water content， as well as a large number of harmful substances such as organic matter， heavy metal ions. In view of the problems with solidification of the waste solid phase in geological drilling， cement was selected as the main agent from three main curing agents： P.O42.5 ordinary portland cement， fly ash and lime； then the basic formula of the curing agent was determined by orthogonal experiment as 25% P.O42.5 ordinary portland cement + 2% PF-3 accelerator +3% RES-1 composite early strength agent， and verified by range analysis. The adding amount of the proppant was also determined at 7%， which can effectively increase the curing strength without increasing mixing difficulty. The curing agent formula was field tested at YK11-2 well for waste drilling fluid treatment with the compressive strength of solidified body up to 1.41MPa， and the pollution index and heavy metal ions meeting the national secondary discharge standard， achieving good treatment effect.