Research On Water Blending Above Hollow Rod Pump For Heavy Oil Viscosity Reducing Technology In Hekou Production Plant Zhan18

Hekou production plant has jurisdiction for heavy oil block.Through field investigation,a total of 18 wells using electrical heating for exploitation,8 wells by dosing viscosity technology exploitation,and another 2 wells should be shut off to meet low temperature in winter because of their low yield and low water cut,and also the transportation is difficult when temperature is extremely low.While Chen jiazhuang heavy oil reservoir is exploited through water blending above hollow rod pump technology for viscosity reduction,the cost is low and its application is successful.With the enhancement of saving energy and reducing consumption standards in oilfield,the production process of using electrical heating,dosing and production difficulties wells in Zhan 18 block does not conform to the requirements,and needs to be modified.The main research work of this paper includes the following aspects:(1)Field investigation of Hekou production plant.We have investigated the wells whose production process need to be modified of Zhan 18 block,the fluid production,oil content,moisture content,the amount of water mixed,wellhead temperature in different oil wells are analyzed.At the same time,investigation of Chen Jiazhuang reservoir production status was conducted.Based on the comparison,we analyzed the feasibility of modification process of production wells in Zhan 18 block.(2)Comparison and analysis of the production process for viscosity reduction currently used in Hekou production plant.The advantage and economic efficiency of water blending for viscosity reduction above the hollow rod pump technology is analyzed.(3)Experimental study.According to the viscosity-temperature characteristics of heavy oil by indoor experiment and successful experience of water blending above hollow rod pump process in Chenjiauzhuang reservoir,the water mixed of single well in Zhan 18 block is determined that crude oil moisture content is not less than 75% after watered and the temperature is 50 degree Celsius.(4)Craft calculation.The temperature field of wellhore is calculated according to the wellhore heat transfer mathematical model in order to determine the scale of water mixed for single well.Combining with field production practice,by scheme comparison and for the goal of the lowest energy consumption,we finally confirm that the water mixture temperature is 60 degree Celsius and the water mixture scale is 584.8 m3/d for 26 wells using electric heating,dosing,or the wells having production difficulty.(5)Efficiency analysis.The economic contrast analysis is made among the three kinds of wellhore viscosity reduction process in Zhan 18 block.Through comparison,we find that it is feasible to make the modification of water blending for viscosity reduction above hollow rod pump of Zhan 18 block in Hekou production plant.(6)Process modification.The water mixing scheme is designed,including building new hollow rod wellhead mixing device;adding water diversion process in the relay station and set up water mixing pipeline network system.Meanwhile,the water hydraulic and thermodynamic calculation is carried out for the pipeline network.