青海油田亲水钝化膜防蜡技术研究
An Inactive Water-Wet Film for Paraffin Inhibition in Qinghai Oilfield
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摘要: 青海油田油井结蜡现象严重,结蜡问题已经成为影响该油田正常生产的重要因素。为了有效解决该问题,实现稳产、增产并降低生产成本,对青海油田清蜡防蜡技术应用现状进行了综合分析,提出了亲水钝化膜防蜡技术。该技术通过加入油管表面处理剂,使其与油管表面反应生成亲水钝化膜,达到防蜡、防腐、防垢的目的。通过理论分析和室内红外光谱试验,从微观角度详细阐述了该技术的防蜡机理:亲水钝化膜中的基团与水发生强氢键作用形成稳定螯合物,从而抑制蜡沉积。室内试验表明,与传统化学防蜡法相比,该技术防蜡率更高,尤其适合于含水30%~50%的油井;现场试验也表明,该技术具有更好的防蜡、防垢、防腐效果,可以延长洗井周期、检泵周期,同时可大大降低油管腐蚀速率,提高油井产量,具有良好的经济效益和广阔的应用前景。Abstract: Paraffin precipitation is seriously affecting crude oil production in Qinghai Oilfield.In order to solve the increasingly worsening problem of paraffin precipitation and achieve the goal of high and stable yields at low cost,this paper comprehensively analyzed the application status of paraffin inhibition technologies in Qinghai Oilfield on the basis of investigation,and proposed a new paraffin inhibition method,namely water-wet inactive film technology.A new chemical is added into tubing to form a water-wet inactive film on tubing surface to inhibit paraffin,corrosion and scale precipitation.Through theoretical analysis and laboratory infrared spectroscopy experiment,the paraffin inhibition mechanism of the new technique was shown in detail from the microscopic view,that is the hydrophilic groups of the inactive film strongly interact with water through hydrogen bonds to form a stable chelate,preventing paraffin deposition.Laboratory experiment and field application show that the new technology works better than traditional chemical paraffin inhibition methods, especially for oil wells with 30%-50% water cut,it can effectively control paraffin,slow corrosion,prevent scale formation,extend purge period and pump inspection interval,raise production,which shows good economic benefits and promising prospects of application.