采气废水中有机物去除方法

Methods of organic contaminants removal in natural gas-produced wastewater

新疆油田天然气开采过程中产生的大量高矿化度、高COD的含油废水,难以处理处置,严重影响了气田的正常生产活动,危害到气田周边土壤安全和荒漠植被的生存。为实现该类废水的达标排放,选取COD和总石油烃含量为考察指标,研究比较了紫外(UV)、臭氧(O3)及紫外臭氧联合处理(UV/O3)法对该类废水的处理效果,进一步考察了p H和O3发生量对UV/O3法处理效果的影响。研究结果表明,3种方法处理废水60 min后,废水COD由处理前的563 mg/L分别下降至处理后的479、334.9和314 mg/L,去除率分别达到14.9%、32.7%和44.2%;而总石油烃含量由处理前的3.86 mg/L分别降至处理后的3.05、1.26和0.20 mg/L,去除率分别达到21.2%、67.4%和94.8%;其中,UV/O3法处理90 min后废水COD降低至148 mg/L,达到《废水综合排放标准GB8978-1996》二级排放标准;p H为7,臭氧发生量为10 g/L时,UV/O3法可应用于采气废水的处理。

The natural gas-produced wastewater,discharged from the Xinjiang Oilfield Company,is difficult to treat because of its high salinity and COD. It seriously affects the normal production of gas,soil environmental safety and plant life around gasfield. In order to achieve standard discharge of wastewater,three methods including UV,O3 and UV / O3 were used to treat the wastewater. After 60 min of treatment by those three methods,the initial COD of 563 mg / L was reduced to 479,334. 9 and 314 mg / L with removal percentage of 14. 9%,32. 7% and 44. 2%,respectively from wastewater. Further,the total petroleum hydrocarbons decreased to 3. 05,1. 26 and 0. 20 mg / L from the initial value of 3. 86 mg / L,with removal rates of 21. 2%,67. 4% and 94. 8%,respectively. The COD of 148 mg / L in wastewater meets the second grade criteria, specified in Integrated Wastewater Discharge Standard( GB /8978-1996),after being treated by 90 min of UV / O3. The p H value of 7 and the amount of oxidation generation for 10 g / h can be used to enhance the treatment efficiency of wastewater.