浅析玛湖油田双节流水合物冻堵防治技术

Disscusion on double throttling process to prevent hydrate freeze plugging in Mahu oilfield

目的针对玛湖油田高含气油井的水合物冻堵防治问题,采用井下与井口双节流喷嘴,进行水合物冻堵预防、调产及放喷解堵研究。方法基于PIPESIM软件计算了油管与喷嘴压力及温度,研究了井下喷嘴对井下油管与井口管线水合物冻堵的影响、井口喷嘴对产量调整的影响。结果双节流喷嘴极差对水合物预防与产量调整具有直接影响,增大双节流喷嘴极差可以大幅降低水合物发生的风险,减小双节流喷嘴极差可以提高井口喷嘴的调产能力,井下喷嘴可以降低井口放喷解堵对储层的不利影响。结论现场试验结果表明,井口油嘴在保持调产能力的同时,井下喷嘴具有水合物冻堵预防与放喷解堵的双重作用,提高了玛湖油田高含气油井的开发效率。

Objective For the special hydrate freeze plugging prevention and control problem of high gas-bearing oil wells in Mahu oilfield,a study on hydrate freeze plugging prevention,production regulation,the release of spray and unblock was conducted by using downhole and wellhead dual throttling nozzles.Methods Based on PIPESIM software,the pressure and temperature of tubing and nozzle were calculated.The effects of downhole nozzle on hydrate freeze plugging in downhole tubing and wellhead tubing were studied.The effect of wellhead nozzle on production adjustment was studied.Results The double throttle nozzle diameter polar difference has a direct impact on hydrate prevention and production adjustment.Increasing the double throttle nozzle diameter polar difference can significantly reduce the risk of hydrate occurrence,and reducing the double throttle nozzle polar difference can improve the production adjustment ability of the wellhead nozzle.The downhole nozzle can reduce the adverse impact of wellhead release unplugging on the reservoir.Conclusions The field test results show that while the wellhead nozzle maintains the production regulation capacity,the downhole nozzle has the dual function of hydrate freeze plugging prevention and blowout unplugging,which improves the development efficiency of high gas-bearing wells in Mahu oilfield.