塔河油田苛刻环境下集输管线腐蚀防治技术应用

目的提升苛刻环境下油气集输管线的腐蚀防护能力,降低腐蚀速率,降低腐蚀穿孔造成的环境污染和人员伤害风险。方法针对塔河油田高H_2S、高CO_2、高H_2O、高Cl~-、高矿化度、低p H值的苛刻内腐蚀环境,通过科研攻关,揭示腐蚀机理,明确腐蚀规律特征,在借鉴国内外防腐技术的基础上,研发出集输管线内挂片法腐蚀监测装置,建立数据、形貌、位置的点腐蚀定量评价方法,以提高腐蚀监测的准确率与评价精度。结果研发出针对H_2O-H_2S-CO_2-Cl~-共存腐蚀环境体系的BX245-1Cr耐蚀钢种管材,其力学性能优异,耐蚀性好,现场试验中点腐蚀速率降低了37.8%,均匀腐蚀速率降低了11.0%。优化改进了非金属管材结构,提升了其耐强冲刷腐蚀性能,并通过添加碳黑与玻璃纤维同缠绕制管消除静电腐蚀。含高H_2S和高CO_2伴生气集输管线采用"预膜+连续加注+批处理"缓蚀剂防护技术,控制均匀腐蚀速率为0.001 mm/a,点腐蚀速率为0.0299 mm/a。含水原油集输管线采用涂层风送挤涂施工进行内涂层防护,解决了60 mm≤DN≤100 mm小口径管线内涂层补口的难题;应用PE管内穿插修复、涂层风送挤涂修复技术对腐蚀集输管线进行治理。结论形成了安全可靠、经济高效、节能降耗且实用的腐蚀防治关键技术系列,现场应用效果显著,为国内油田的腐蚀防治提供了技术借鉴与应用经验。

Corrosion Prevention and Control Technology Application of Gathering and Transportation Pipelines in Tahe Oilfield

Objective To improve the corrosion prevention ability of oil and gas gathering pipelines in the harsh corrosive envi-ronment , reduce the corrosion rate and the risk of environmental pollution as well as personnel injury caused by corrosion and perfo-ration. Methods The internal corrosive environment is very harsh with high H2 S, CO2 , H2 O, Cl-, high mineralization degree and low pH characteristics in Tahe Oilfield. By scientific research, the corrosion mechanism was revealed and the characteristics of cor-rosion law was determined. Referring to the corrosion prevention technology in China and foreign countries, the corrosion monitor was developed by self-dependent innovation and used in gathering and transportation pipeline, the pitting corrosion evaluation meth-od of data, morphology and position was established, in order to improve the accuracy of monitoring and the precision of evaluation. Results Corrosion resistant steel pipe BX245-1Cr was invented, which had excellent mechanical properties and good corrosion re-sistance in H2 O-H2 S-CO2-Cl- corrosion environment. The corrosion rate was decreased by 37. 8% and the corrosion rate was de-creased by 11% in the field test. The structure of nonmetallic pipe was optimized and improved, the resistance against strong erosion-corrosion was enhanced and electrostatic corrosion was eliminated by addition of the winding pipe of carbon black and glass fiber . The gas gathering pipelines with high contents of H2 S and CO2 used the corrosion inhibitor technology of"prefilming-continu-ous filling-batch processing", which controlled the average corrosion rate at 0. 001 mm/a, and the point corrosion rate at 0. 0299 mm/a. The anticorrosion coating with air blow compressive smearing technology was used in oil gathering and transportation pipe-line, which solved the problem of crack repair in the internal coating of 60 mm≤DN≤100 mm pipeline. The interpolation recovery technique of polyethylene pipe and the air blow compressive smearing technique were used in repairing of corroded gathering and transportation pipelines. Conclusion These results formed several corrosion prevention and control key technologies which were safe, economic, efficient, energy saving, and practical. The oilfield application effect was remarkable and the research provides technical reference and practical experience for corrosion control in domestic oil fields.