不同预处理法对PEM钻井废液固-液分离影响研究

Effect of different pretreatment methods on solid-liquid separation of PEM waste drilling fluid

固-液分离方法对钻井废液处理的工艺与设备设计具有重要的指导意义。本文对比了絮凝剂对经不同预处理的钻井废液固-液分离的影响。结果表明:单独使用FeCl3的浓度为6250mg·L^-1时脱液率为53%,水相pH值为4.9;加水稀释后FeCl3浓度为7407mg·L^-1时,脱液率为40%,水相pH值为3.73;HCl预处理时钻井废液起泡,添加高分子聚合物助凝剂PF-Plus而未加絮凝剂的HCl预处理钻井废液的固、液分离效果最佳,处理后水相pH值均小于1;CaCl2/NaOH共沉淀处理后,脱液率为46%,水相pH值位于11~12之间。本文对PEM钻井废液处理的现场工艺与设备设计具有重要指导意义。

Solid-liquid separation(SLS) method has the great directive significance to the equipment and technique design of waste drilling fluids(WDF)treatment. In this paper, the effects of different flocculants on the SLS of PEM WDF without any pretreatment were compared with those which were under three different pretreatments(dilution pretreatment, HCl pretreatment and NaOH pretreatment). The results show that the dehydration rate is 53% and pH value of the water is 4.9 when the concentration of FeCl3 is 6250 mg·L^-1. The dehydration rate of the SLS of WDF with dilution pretreatment is 40% and p H value of the water is 3.73 when the concentration of FeCl3 is7407 mg·L^-1. The WDF foams when it was pretreated by HCl. After HCl pretreatment, the WDF with coagulant PFplus but without any flocculant showed the best SLS result. Through CaCl2/NaOH coprecipitation treatment,the dehydration rate is 46% and the pH value of the water is between 11 and 12. This paper shows the great directive significance to the equipment and technique design of PEM WDF treatment.