页岩气采出水处理工艺试验研究

Research on Treatment Process of Shale Gas Wastewater

页岩气采出水具有含盐量高和污染物成分复杂的特点,污染物中含有机物、悬浮物和油等,针对页岩气采出水特点,提出采用“旋流气浮-三维多效电催化氧化-脱盐系统”联合处理工艺对页岩气采出水进行试验研究,其中脱盐系统包括过滤装置、电渗析装置和反渗透装置。中试结果表明:旋流气浮对CODcr、石油类和SS的去除率分别为49.3、51.2和51.9;三维多效电催化氧化对CODcr、石油类和SS的去除率分别为66.7、96.6和93.6;脱盐系统产水CODcr52mg/L,Cl-230mg/L,SS和石油类未检出,满足GB8978-1996《污水综合排放标准》和DB51/190-93《四川省水污染物排放标准》一级排放标准。试验研究为页岩气采出水达标外排处理工程化应用提供了技术支撑。

The shale gas sewage contains high salinity and complex pollutant composition, such as different organics, suspended solids and oil, etc. According to the characteristics of the shale gas wastewater, we propose a treatment process containing swirl type air floatation, three dimensional multiple effect electric catalytic oxidation and a desalination system. The desalination system consists of filtration equipment, electrodialyzer and reverse osmosis equipment. The results of the pilot experiment show that the removal rates of CODcr, oil and SS are 49.3 ,51.2 and 51.9 respectively during the swirl type air floatation;while during three dimensional multiple effect electric catalytic oxidation, CODcr, oil and SS are removed by 66.7.,96.6 and 93.6 respectively. The CODcr and Cl-concentration of the effluent from the desalination system is 52mg/L and 230 mg/L, respectively. The oil and SS are not detected. The effluent quality indicators meet the requirements specified in the first class of the Integrated Wastewater Discharge Standard(GB 8978-1996) and the Sichuan Provincial Wastewater Discharge Standard(DB51/190-93), which provides technical support for engineering application of shale gas wastewater discharge.