大牛地气田压裂返排废液催化氧化联合处理实验

An experimental study of the combined treatment of catalytic oxidation and fracturing waste fluid treatment in the Daniudi Gas Field

压裂返排废液具有高COD值、高稳定性、高黏度等特征,处理达标难度较大。为此,以大牛地气田的压裂返排液为研究对象,在常规处理工艺基础上增加预氧化步骤,最终确定了"预氧化—混凝—催化氧化—吸附"的处理工艺。重点研制了压裂废液氧化处理的催化剂(Cu-C催化剂),通过实验确定了最佳工艺参数条件。重点考察了催化氧化处理工艺条件,即在pH值为6,氧化剂(ClO2)投加量为2g/L,催化剂投加量为0.6%(质量/体积)的条件下,COD值降至164mg/L,进一步吸附处理后COD值降至97mg/L,达到国家《污水综合排放标准》的一级标准要求,处理成本为73.15元/m3。该处理工艺简单,成本较低,具有一定的应用价值。

The fracturing waste fluid has a high chemical oxygen demand（COD） value,high stability,and high viscosity,so it is too difficult to handle to meet the standard requirement.In view of this,in a case study conducted in the Daniudi Gas Field,the pre-oxidation is added based on the regular treatment procedures,thus the developed technology follows the order from pre-oxidation to coagulation,catalytic oxidation,and adsorption.This study focuses on the research and development of the catalyst of Cu-C,on this basis,the optimal conditions of parameters are determined through experiments,especially the condition of catalytic oxidation,that is,when the pH value is 6,the oxidant ClO 2 dosage is 2g/L,and the catalyst dosage is 0.6%（m/v）,the COD value will be reduced to be 164mg/L then to 97mg/L after the further adsorption treatment.The achieved good results meet the requirement of the first grade written in The Comprehensive Wastewater Discharge National Standard with the treatment cost of only 73.15Yuan RBM per m 3.