In order to improve oil recovery,most of the domestic oil field is developing polymer flooding technology and gradually applied.In the process of industrialization of polymer flooding technology,it is inevitable to produce polymer-carrying produced water.The conventional disposal method is difficult to reach the standard of produced water reinjection,and the polymer-carrying produced water is increasing year by year,so it is urgent to study the process design of it.In this paper,the expansion project of a polymer-carrying produced water treatment test station(phase 2)in China is selected as the research object.In order to analyze and solve a series of problems in the 1st-phase project,and provide the theory and data support for the process design of the 2nd-phase project.By researching on the mature technology of water treatment in Daqing Oilfield,compared with the water quality conditions,anglicizing of the applicability of the process in this oilfield,it can confirm the main process.The optimization and improvement of the problems occurred in each operation module can be proposed through the laboratory test.(1)The settlement performance test confirm that the optimal residence time of the tank is 12 h.(2)When the temperature is 35 DEG C,and p H is 7~8,and dissolved oxygen is 4.0mg/L,and the oil content is bellow than 100mg/L,the biological treatment effect is good.(3)The oil content and SS can both be less than 20mg/L with coagulation and flotation and it need cost 5.6yuan for 1 tons of water.(4)We can set the scaling pool or add scale inhibit to solve the problem of scaling in biological pool.After investigation and experimental results,two primary processes of polymer-carrying produced water treatment are obtained and we can get the optimum process conditions for key modules. |