渤海J 油田生物酶-化学复配解堵技术

Biological Enzyme and Chemical Unplugging Treatment of Crude Oil in Bohai J Oilfield

渤海J油田开发过程中,因原油中微晶蜡含量较高,其对温度、压力较为敏感,从而在采出过程中易析出沉积,导致生产井出现井筒及近井地带堵塞、井底流压上升等现象,严重影响油田的正常生产。本文利用生物酶WZ7与化学解堵剂LV复配开展原油堵塞解堵技术研究,研究了复配体系的配伍性、乳化、原油剥离、降黏、界面活性、溶蚀、储层渗透率恢复性。结果表明:5%生物酶WZ7/1%化学解堵剂LV复配体系在油藏温度(57℃)和90℃下对垢样溶蚀率分别达到42.79%和92.03%,垢样剥离效率达到80%以上,原油降黏率达83%~92%之间,形成的油水乳液稳定性较高,并表现出良好的乳化性能;储层渗透性恢复物模实验发现,该体系油藏温度(57℃)下渗透恢复率为43.96%,在90℃条件下渗透恢复率达74.97%,显示该解堵体系针对渤海油田因重质组分沉积造成的原油堵塞具有较强的解堵能力。

During the development of Bohai J Oilfield,because of the high content of microcrystalline wax,the crude oil is more sensitive to temperature and pressure,and easily precipitates and deposits during the production process,which leads to blockages in the wellbore and near-wellbore areas of production wells,and increases in bottom hole pressure,etc.This phenomenon has seriously affected the normal production of oil fields.In response to this problem,the combination of biological enzymes and chemical plugging agents was used to carry out crude oil unplugging technology research,and the compatibility,emulsification,crude oil stripping,viscosity reduction,interfacial activity,dissolution,and reservoir permeability recovery of the compound system was studied.The results showed that the 5%bio-enzyme WZ7/1%chemical unplugging agent LV compound system could reach 42.79%and 92.03%of the scale sample at the reservoir temperature(57℃)and 90℃,respectively,and the scale sample peeled off,the efficiency being of more than 80%.The viscosity reduction rate of the crude oil was 83%—92%,and the formed oil-water emulsion had higher stability and better emulsification performance.the reservoir permeability recovery physical model experiment indicating that the permeability recovery rate at temperature(57℃)was 43.96%,while the permeability recovery rate at 90℃was 74.97%,indicating that the system had a strong ability to remove the plugging of crude oil caused by heavy component deposition in Bohai oilfield.