The common practice of using chemicals and solid-entrained liquids to remove soft scales in production tubings is associated with a high risk of contaminating the environment and eroding pipe internal surfaces. Due to the suspended solids, the current practices are also characterized by high pumping costs and are more problematic to rotating parts of machinery than freshwater. As a cheap and less risky alternative to these corrosive chemicals and liquids, this paper investigates the feasibility of utilizing multiple high-pressure (HP) water jets for the same objective. A total of 54 experimental trials were conducted to study the effects of four factors on the efficiency of scale removal with multiple flat-fan nozzles at an orientation of 25°. The factors investigated are (1) number of nozzles; (2) spray injection pressure; (3) stand-off distance between the spray nozzle and target scale; and (4) condition of the production tubing: ambient and pressurized. Details of the experimental set-up, equipment and procedure are provided. The results of these controlled experiments show a positive correlation between descaling efficiency and spray injection pressure. The same set of experiments reveals a negative correlation between descaling efficiency and nozzle count, as well as between descaling efficiency and spray stand-off. However, for the scale samples and range of parameters investigated in this study, descaling efficiency did not exhibit significant dependency on the chamber conditions, i.e. ambient versus pressurized. The results of this study provide some insights into the feasibility of multiple HP water jets as a cleaner alternative to the use of corrosive chemicals and solid-entrained liquids to remove soft scales in production tubings in oil fields and other applications.

使用化学药品和固体夹带的液体去除生产管道中的软垢的普遍做法与污染环境和腐蚀管道内表面的高风险有关。由于存在固体悬浮物，目前的做法还具有抽水成本高的特点，与淡水相比，机器的旋转部件更容易出现问题。作为这些腐蚀性化学药品和液体的廉价且风险较低的替代品，本文研究了为同一目的而使用多个高压（HP）水射流的可行性。总共进行了54次实验，以研究四个因素对在25°方向上使用多个平扇喷嘴的除垢效率的影响。研究的因素是（1）喷嘴数量；（2）喷雾喷射压力；（3）喷嘴与目标刻度之间的间距；（4）生产管道的状况：常温和加压。提供了实验装置，设备和程序的详细信息。这些受控实验的结果表明除垢效率与喷射压力之间呈正相关。同一组实验揭示了除垢效率与喷嘴数量之间的负相关，以及除垢效率与喷雾支座之间的负相关。然而，对于本研究中所研究的水垢样品和参数范围，除垢效率并未显示出对腔室条件的显着依赖性，即环境与加压之间的关系。