Colloidal gas aphrons (CGA) are finding increasing application in depleted oil and gas reservoirs because of their distinctive characteristics. To overcome the limitations of its application in high-temperature drilling, a modified starch foams stabilizer WST with a temperature resistance of 160 °C was synthesized via radical polymerization. The chemical structure of WST was characterized by Fourier infrared spectroscopy and results showed that all three monomers acrylamide, 2-acrylamido-2-methyl-1-propane sulfonic acid, and N-vinylpyrrolidone have been grafted onto starch efficiently. Based on the microscopic observations, highly stable aphrons have been successfully generated in the WST-based CGA drilling fluids within 160 °C, and most aphrons lie in the range of 10–150 μm. WST can provide higher viscosity at high temperatures compared to xanthan gum, which helps to extend foam life and stability by enhancing the film strength and slowing down the gravity drainage. Results show that WST-CGA aged at elevated temperatures (120–160 °C) is a high-performance drilling fluid with excellent shear-thinning behavior, cutting carrying capacity, and filtration control ability. The significant improvement of filtration control and well-building capability at high temperatures is an important advantage of WST-CGA, which can be attributed to the enhancement of mud cake quality by WST.

中文翻译：

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改性淀粉在耐高温胶体气体泡沫（CGA）钻井液中的应用

由于其独特的特性，胶体气体泡沫 (CGA) 在枯竭的油气藏中得到越来越多的应用。为了克服其在高温钻井中应用的局限性，通过自由基聚合合成了一种耐温为160℃的改性淀粉泡沫稳定剂WST。WST的化学结构通过傅里叶红外光谱表征，结果表明丙烯酰胺、2-丙烯酰胺基-2-甲基-1-丙磺酸和N-乙烯基吡咯烷酮三种单体均已有效接枝到淀粉上。基于显微观察，WST 基 CGA 钻井液在 160 °C 内成功生成了高度稳定的 aphron，大多数 aphron 位于 10-150 μm 范围内。与黄原胶相比，WST 可以在高温下提供更高的粘度，这有助于通过增强膜强度和减缓重力排水来延长泡沫寿命和稳定性。结果表明，WST-CGA 在高温 (120–160 °C) 下老化是一种高性能钻井液，具有优异的剪切稀化行为、切削承载能力和过滤控制能力。高温下过滤控制和建井能力的显着改善是 WST-CGA 的一个重要优势，这可以归因于 WST 提高了泥饼质量。结果表明，WST-CGA 在高温 (120–160 °C) 下老化是一种高性能钻井液，具有优异的剪切稀化行为、切削承载能力和过滤控制能力。高温下过滤控制和建井能力的显着改善是 WST-CGA 的一个重要优势，这可以归因于 WST 提高了泥饼质量。结果表明，WST-CGA 在高温 (120–160 °C) 下老化是一种高性能钻井液，具有优异的剪切稀化行为、切削承载能力和过滤控制能力。高温下过滤控制和建井能力的显着改善是 WST-CGA 的一个重要优势，这可以归因于 WST 提高了泥饼质量。