一种泡沫钻井液废水的处理

Foam Drilling Fluid Wastewater Treatment

空气(氮气)泡沫可循环钻井过程中,泡沫钻井液会产生大量废水,直接排放会对环境造成严重污染。泡沫钻井液废水COD值高,且富含表面活性剂,其单一处理技术存在一定的局限性。本研究对各种处理剂及其效果进行了比较,并对各处理过程中的关键影响因素进行对比分析,制订了"混凝-氧化-吸附"的组合处理工艺。实验结果表明,废水的pH值,处理剂的加入量,处理剂的作用时间等对于COD的去除均有一定影响。按照国家标准对处理后的废水进行COD测定,结果表明:聚合氯化铝、钠基膨润土、次氯酸钠和活性炭4种处理剂对此种泡沫废水的处理效果较好,其加入量分别为0.2%、1.4%、11.2%和1.2%,处理时间分别为5h、6h、7h和8h。通过多步骤的处理,成功将泡沫钻井液废水COD值从高达4560mg/L降至200mg/L以内,使其得到有效治理。

Foam drilling fluid used in recirculated air(nitrogen) foam well drilling technology will produce a large quantity of wastewater,direct discharge of which will seriously pollute the environment.Such wastewater has high COD values and contains large amounts of surfactant.No single technology is able to treat such wastewater solely.This article compares the effects of all types of treatment agents,analyzes the key affecting factors to various treatment processes and presents a coagulation-oxidation-absorption integrated treatment process.Experimental results show that pH of wastewater,the dosage of treatment agent used and the duration of treatment agent action all have an effect on the removal of COD.Measurement of COD in treated wastewater according to the relevant national standard shows that polymeric aluminum,Na-based bentonite,sodium hypochlorite and activated carbon treatment agents are the most effective to such foam wastewater.The dosages of these four agents needed are 0.2%,1.4%,11.2% and 1.2% respectively and their action durations are 5,6,7 and 8 hours.The COD value of such foam drilling fluid wastewater could be reduced to below 200mg/L from as high as 4560mg/L.