Precipitation of the scale in the oil and gas reservoirs, surface and subsurface equipment, and processing and production facilities is a big problem as it affects petroleum production. The scale precipitations decrease the oil and gas production and cause economical loss. Solving this issue requires an engineering investigation to provide a safe, efficient, and economic solution. Consequently, this study proposed a developed dissolver for barium sulfate scales, where two field-scale samples were collected from different locations. The compositional analysis for scale samples showed that sample 1 is 100% barium sulfate where sample 2 has 97.75% barium sulfate and 2.25% of quartz. The composition of the developed dissolver has diethylenetriamine pentaacetic acid (DTPA) as a chelating agent, oxalic acid, and tannic acids as an activator, nonionic surfactant, and water as the base fluid. The new dissolver was investigated with extensive lab tests to determine the dissolution efficiency, precipitation tendency for the dissolved scale solids, corrosion rate, and fluid-rock interaction. The obtained successful results indicated that the developed dissolver had a dissolution efficiency for two real barium scale samples as the results showed 76.9 and 71.2% at 35°C and 91.3 and 78.4% at 90°C for samples 1 and 2, respectively. The new solution has a great performance compared with common scale dissolvers in the oil field as hydrochloric acid, ethylenediaminetetraacetic acid, and diethylenetriamine pentaacetic acid. The developed dissolver showed a very low precipitation tendency for the scale dissolved solids (1.9 and 3.2% for samples 1 and 2, respectively) under 35°C for 24 hours. Without any additives of corrosion inhibitors, the corrosion rate was 0.001835 g/cm² at 6.9 MPa and 100°C for 6 hours. Injecting the developed dissolver for damaged sandstone core sample with barite mud by flooding test showed a return permeability of 115%.

中文翻译：

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低温去除硫酸钡水垢

油气储层，地表和地下设备以及加工和生产设施中的水垢沉淀是一个大问题，因为它影响石油生产。结垢沉淀降低了油气产量，并造成了经济损失。解决此问题需要进行工程研究以提供安全，高效和经济的解决方案。因此，这项研究提出了一种开发的硫酸钡水垢溶解器，其中从不同位置收集了两个田间水垢样品。对水垢样品的成分分析表明，样品1为100％的硫酸钡，其中样品2为97.75％的硫酸钡和2.25％的石英。研制的溶解器的成分包含二乙烯三胺五乙酸（DTPA）作为螯合剂，草酸和鞣酸作为活化剂，非离子表面活性剂，并以水为基础液。对新的溶解器进行了广泛的实验室测试，以确定其溶解效率，溶解的水垢固体的沉淀趋势，腐蚀速率和流体-岩石相互作用。获得的成功结果表明，开发的溶解器对两个真实钡垢样品具有溶解效率，因为结果分别显示样品1和2在35°C时为76.9％和71.2％，在90°C为91.3％和78.4％。与盐酸，乙二胺四乙酸和二亚乙基三胺五乙酸等在油田中常见的规模溶解器相比，该新解决方案具有出色的性能。发达的溶解器在35°C下放置24小时后，对水垢溶解的固体显示出非常低的沉淀趋势（样品1和2分别为1.9％和3.2％）。²在6.9 MPa和100°C下放置6小时。通过注水试验，用重晶石泥注入损坏的砂岩岩心样品的溶解器，其回油渗透率达115％。