The Research Of Freewater Knockout Facilities For The Polymer Flooding

This study aims to master the FWKO structure, the treating processes and oilfields applications' technology of FWKO.The FWKO is one of the key facilities in treating Produced fluid of polymer flooding in Daqing oil field. The study is divided into three steps, i.e. (1) indoor's coalescence test, (l)middle-scale production use. (3) the oilfields application uses.Through the indoor coalescence test and middle scale production use and the production application uses, the research processes have been finished. To sum up above researching results, we obtain the conclusions as follows.1. Through the indoor coalescence test, we have determined the structure parameter of coalescence materials of FWKO and determined the affecting factors of coalescence material; they were the bases for the use of FWKO in oilfields production use. The test and simulating calculation indicate that the factors influencing the removing efficiency of coalescence material are flow rate, the packing length of coalescence material, the ratio-surface the contents of coalescence material. The most influencing factor is flow rate. At a certain range of the packing length, increasing the length of packing is propitious to the separation of water and oil. If the length is more than a fixed length, increasing the length of packing, it is no use to increasing the efficiency. So determining the suitable packing length is valid for practical uses.2.Through the middle scale production use, we have gained that with the appear of polymer in the Produced fluid, the viscosity of water was increased, it made the separation of free-water become difficulty. The viscosity of waterincreased with the content increase of polymer in the Produced fluid. The quality of FWKO is respect to polymer contents of the Produced fluid, the less of polymer contents, the shorter of the settle time. The more of polymer contents, the longer of the settle time. Otherwise, the knockout efficiency of free-water is related to the type and the quantity of demulsifier. When treating the produced fluid with polymer, we recommend that it is better to use the demulsifier of fpw-320.3.Through the production applications use, the research results were been improved and the parameters suited for different oilfields have been taken out. The oilfields applications use proved that the developed FWKO were satisfied to the needs for daqing oilfield to continuously increase the treating Produced fluids of polymer flooding, and the parameters are satisfied for the preconcerted value. The achieved value are: the inlet water contents: : 60~90%, the operating temperature 38~42℃, settling time: 20min ,the demulsifier dosage: Fpw-320 20mg / L or Sp69 30~40mg / L , the outlet : water contents in oil < 30%, oil contents in water <2000 mg / L. at the same time ,we have established a set of FWKO suited for polymer flooding.4.to apply FWKO of polymer flooding, to construct a treating station can save capital construction investment 1.2 million, in one year 3.109 millions of production expenses could be saved. In daqing oilfiled 30 sets united stations have been constructed so only the saved capital construction investments would be 36 millions, in one year the production expenses would save to 93.027 millions. The economy benefits are tremendous.