Study On The Performance Of Profile Control Agent Prepared By Polymer Flooding Produced Fluid Sediment

With the application of polymer flooding technology in oilfield development,a large number of polymer flooding produced fluid sediments are produced.Sediment not only causes environmental pollution,but also affects the water quality of sewage treatment pipe network and the normal operation of sewage treatment system.The produced fluid deposits of polymer flooding mainly exist in colloidal or oily sand viscous form,and contain polyacrylamide derivatives,which is feasible to be used as raw materials for preparing profile control agents.According to the characteristics of polymer flooding produced fluid sediments collected at different locations,this paper optimizes the treatment formula and process,and prepares profile control agent to realize the reuse of polymer flooding produced fluid sediments.By analyzing the composition and performance of polymer flooding produced fluid deposits,the reuse technology of polymer flooding produced fluid deposits collected at different locations was determined.Among them,the sediments washed out from polymer injection wells are mainly in the form of soft gel with viscoelasticity,and the main organic components are polyacrylamide derivatives,which have water absorption and swelling properties after drying.After drying,granulating,grinding and sieving,they are prepared into bulk swelling particle profile control agents.The main component of the sediment stored in the storage pool of the joint station is oily sand,with an oil content of up to 22.75%.The median particle size after filtration and grinding treatment is 8.7μm.It is preferred that HPAM with a molecular weight of 25 million be used as suspending agent and OP-10 as dispersant,and it can be compounded into suspension profile control agent,or it can be compounded into jelly profile control agent by adding HPAM and phenolic organic chromium compound crosslinking agent.Laboratory core experiments show that the plugging rate and erosion resistance rate of the three compound profile control agents are over 90%,and they have good performance and meet the requirements of field profile control.In this paper,the methods of collecting,transporting,separating,crushing,filtering,profile control and injection of produced fluid from polymer flooding are optimized,and the process flow of sediment surface treatment is optimized.The field profile control test was followed,and the high permeability Dong-2 member was selected as the main profile control reservoir.The field construction displacement is 10-40 m³·h^-1,and the construction pressure is 10-17MPa.The test shows that the profile control effect of combining sediment compound profile control agent with gel profile control agent prepared in original oilfield is better than that of using only a single profile control agent.When polymer flooding produced fluid sediments are used to prepare profile control agents,it is necessary to overcome the difficulties of screening,filtering,crushing and agent optimization,so as to obtain profile control agents with good suspension and stability,and to solve the problems of solid particle migration,water flooding breakthrough resistance and water absorption and expansion performance of the gel after drying.By adopting appropriate formula and technology,polymer-containing sediments can be prepared into profile control agents for use,so as to solve the problem that polymer-containing sediments are difficult to be disposed of harmlessly,and have good popularization and application prospects.