交联胍胶返排液回注预处理工艺研究

Study on Pretreatment Technology of Cross-linked Guanidine Gum Backflow Fluid Reinjection

随着“水平井+体积压裂”开发模式的广泛应用,交联胍胶采出水的处置成为制约新疆油田发展的突出问题。交联胍胶采出水的处置去向主要有复配、回注和外排。其中,回注地层工艺存在现有工艺无法处理、特殊工艺成本较高的问题,为此开展了处理后的交联胍胶采出水掺入常规采出水处理系统的研究。针对电化学处理环节使用的药剂种类,采用正交试验筛选出每种药剂的合适加药量,制定出了一套针对交联胍胶采出水的“气浮—电化学—过滤”预处理技术,并将预处理工艺及相应药剂应用于现场试验中。结果表明:采用“气浮—电化学—过滤”处理技术对交联胍胶采出水进行处理,处理后水质悬浮物质量浓度≤20 mg/L,含油质量浓度≤20 mg/L;掺入常规采出水系统后,出水水质满足回注油田水质标准,从而实现了新疆油田交联胍胶采出水的有效循环利用,降低了企业的用水成本。

With large-scale applications of the development mode of“horizontal well+volume fracturing”,the treatment of cross-linked guanidine gum produced water becomes a prominent problem restricting the development of Xinjiang Oilfield.The main disposal directions of cross-linked guanidine gum produced water are compounding,reinjection and drainage.Because conventional technology cannot be used in dealing with cross-linked guanidine gum produced water and the cost of formation reinjection technology is high,the research of cross-linked guanidine gum produced water after treatment mixing with conventional produced water treatment system is carried out in Xinjiang Oilfield.According to the chemical types used in the electrochemical treatment,the orthogonal test is used to screen out the appropriate dosage of each chemical,and a set of"air floating-electrochemical-filtration"pretreatment technology is developed for cross-linked guanidine gum produced water.Then the pretreatment process and the corresponding chemical are applied in the field test.The results show that the"air floating-electrochemical-filtration"treatment technology is used to treat the cross-linked guanidine gum produced water.After treatment,the water quality reached the suspended mass concentration≤20 mg/L and the oil-bearing mass concentration≤20 mg/L.After mixing into the conventional produced water system,the effluent water quality met the water quality standard for injection into oilfield,thus achieving the effective recycling of cross-linked guanidine gum produced water in Xinjiang Oilfield,and reducing the cost of water for enterprises.