缓蚀剂引起气井油管堵塞原因分析及对策

在目前的技术条件下，对含硫气井井下油、套管，最经济、最有效的保护措施就是加注适宜的缓蚀剂。缓蚀剂的选择应有针对性，不同气井腐蚀因素不同，其缓蚀剂品种也将不同。针对四川盆地东部地区气井近年来出现的因缓蚀剂引起的油管堵塞和现场实际解堵情况，结合井下垢物分析及解堵过程中对堵塞物的推断，分析得出：缓蚀剂引起油管堵塞的主要原因是缓蚀剂适应性差、加注制度不合理、缓蚀剂质量缺陷以及腐蚀产物裹夹等综合因素，提出了缓蚀剂入井前需进行配伍型试验，并要求加注缓蚀剂的气井必须定期洗井，同时加强缓蚀剂质量控制、现场管理和生产管理等措施，确保了气井在加注适宜的缓蚀剂下腐蚀得以延缓，同时尽可能地减少了因缓蚀剂造成的井筒堵塞，为生产决策提供了依据。

ANALYSIS ON THE REASONS FOR THE GAS WELL TUBING BLOCKING CAUSED BY CORROSION INHIBITOR AND ITS COUNTERMEASURES

Under current technical conditions, to add proper corrosion inhibitor is the most economical and effective protective measures to protect the down hole oil and casing in sour gas wells. The selection of corrosion inhibitor should have its pertinence, which means different corrosion inhibitors would be chosen according to different corrosion factors to gas wells. In view of the tubing blocking caused by corrosion inhibitor appeared in the eastern Sichuan basin in recent years and its practical field solutions，combined with the analysis on the underground scale and inference to the stemming in the process of removing plugging, the paper summarized the main reasons that the corrosion inhibitor causes tubing blocking, which include the poor adaptability of corrosion inhibitor, the unreasonable adding system, the defect of corrosion inhibitor quality, as well as the wrapping and clip of corrosion product. It is proposed that a compatibility type experiment should be taken before putting corrosion inhibitor into wells and regular well cleanout should be implemented to the gas wells adding corrosion inhibitor. Meanwhile, strengthening the control of corrosion inhibitor quality, field and production management, are put forward to ensure that the corrosion can be delayed in the gas wells where suitable corrosion inhibitor is added and shaft blocking caused by corrosion inhibitor can be reduced as much as possible, which provide basis for production decisions.