破胶絮凝-预氧化-深度氧化处理压裂返排液

以四川德阳某气田作业现场的压裂返排液为研究对象,通过对其水质特征、治理现状进行分析,提出了破胶絮凝-预氧化-深度氧化的处理工艺。通过实验研究,确定了性能优良的破胶絮凝剂、预氧化剂及Fenton氧化体系;并得出最佳实验条件:CaO、Al2(SO4)3及FeSO4的投加量均为5 000 mg/L;在不调节出水pH、加入预氧化剂高锰酸钾500 mg/L、反应时间15 min的条件下,CODCr去除率达到58%;调节废水pH至3.0~4.0,再采用Fenton氧化处理,其投加量为H2O2(30%)6 mL/L、及FeSO4·7H2O 5 000 mg/L,反应时长2 h。采用上述处理工艺,处理后废液的主要污染指标CODCr降低了79%,从而为达标处理创造了条件。

Gel breaking-coagulation-pre oxidation-advanced oxidation treatment of fracturing flow-back fluid

Focus on the research of fracturing flow-back fluid of a gas field workplace in Sichuan Deyang, analysis the quality characteristics and treatment situation of the fluid, and investigate the treatment process of gel breaking-coagulation-pre oxidation-advanced oxidation. Through the experimental study, the excellent-property system of gel-breaker, inorganic coagulants, pre-oxidants and Fenton oxidation has been established and the optimum experimental condition has been concluded as follow: respective dosing quantity of 5000mg/L of calcium oxide, aluminum sulfate and ferrous sulfate; keep constant of the water pH, adding pre-oxidant potassium permanganate 500mg/L, CODCr removal rate reached 58% under the reaction time 15min; changing the water pH to 3.0-4.0 and using Fenton oxidation treatment with the dosage of H2O2(30%)6ml/L and FeSO4?7H2O 5000mg/L , CODCr removal rate reached 79% after the reaction time 2h. Overall, the major pollution indicator of CODCr in waste liquor is effectively reduced by means of those treatment processes, which create the condition for standards.