声化学集成臭氧技术处理钻井废液实验研究

目前国内外油气井钻井废液的处理方法主要有直接排放、填埋、坑内密封、土地耕作、固化法、焚烧法、微生物法等，这些方法都存在处理费用高、处理不彻底、适用范围窄等问题，其中钻井废液的脱稳混凝处理是关键。针对钻井废液组成、特点、危害及目前国内外处理现状，根据声化学、臭氧氧化作用机理，提出了采用声化学复合臭氧氧化集成技术达标处理钻井废液的研究思路。实验分析了影响声化学脱稳及声化学复合臭氧深度处理因素，并得出如下钻井废液达标处理优化工艺：①声化学脱稳混凝处理，声强30 W/cm²、声频35 kHz、作用时间20 min、无机混凝剂PAC加量0.6%；②声化学复合臭氧氧化深度达标处理，声强35 W/cm²、声频35 kHz、O₃浓度1 000 mg/L、反应时间20 min。同时，采用电镜扫描分析了声化学脱稳混凝处理后絮体表面特征，分析了其混凝作用机理。实验研究的结果表明：该处理技术具有化学试剂加量少、二次污染较低、药剂成本低、处理效果明显等优点，同时，钻井废液处理后能够实现达标排放。

An experimental study of waste drilling fluids treated by the combination of sonication and ozonation

The commonly used methods of treating waste drilling fluids in the world mainly include direct emissions,landfill,sealed pits,land cultivation,curing,incineration,bioassay,etc.However,all the above methods are not good enough to treat waste drilling fluids in fields owing to a high treatment cost,an incomplete treatment,and a narrow application scope.The clincher of waste drilling fluids treatment is the coagulation,the destabilization of colloids by addition of chemicals that neutralize the negative charges.In view of this,this paper first introduces the components,features,potential hazards of waste drilling fluids as well as the present status of treatment all over the world.Then,according to the mechanism of sonochemistry and ozone oxidation,the technology of sonication combined with ozonation is put forward to treat waste drilling fluids so as to reach the standards.Through the experimental analysis of the influencing factors of this technology,the optimal treatment process is determined as follows.First,sonochemical coagulation and destabilization treatment: sound intensity of 30 W/cm2,acoustic frequency of 35 kHz,the O3 content of 1000 mg/L,operation time of 20 min,and the addition of inorganic coagulant PAC of 0.6%.Second,sonochemical ozone oxidation treatment to reach the standards: sound intensity of 35 W/cm2,acoustic frequency of 35 kHz,the O3 content of 1000 mg/L,reaction time of 20 min.Meanwhile,the SEM analysis is done of the surface characteristics of flocs after the treatment and the mechanism of coagulation is also studied.The results of this experimental study show that this new technology has advantages such as less addition of chemical reagents,a low degree of secondary pollution,low cost of chemical reagents,obvious treatment effects,and so forth;and the most important of all,the waste drilling fluids will be discharged after being treated by this new method,which completely meets the emission standard.