威远页岩气井低压低产期稳产技术与实践

威远页岩气井具有初期产量高、递减快的特征，根据生产特征可分为压后返排、快速递减、低压低产三个生产阶段，不同阶段生产特征差异明显。低压低产阶段，气井产量低、压力低、递减速度慢、生产周期长，产量贡献达60%,是稳产技术实施的主要阶段，但生产效果易受井筒积液、压裂窜层水淹、外输压力波动、井筒堵塞等因素影响。针对各种产量影响因素及不同类型问题井，形成了以增压、泡排、柱塞、气举、井筒清洗及其组合措施的老井稳产技术对策，以实现快速复产，例如轻微积液井优先开展增压并采取泡排措施，间歇积液井优先采取泡排或柱塞工艺，严重积液井优先采取反举或关井气举措施，井筒堵塞井采取井筒清洗或连油冲洗，压窜水淹井优先采取同步降压气举、连油气举及替喷等措施。通过页岩气井低压低产期稳产技术的实践，形成专项技术模板，有效治理气井各类生产难题，最大程度挖潜气井产能，提升老井持续稳产能力，实现页岩气区块高效开发。

Stable Production Technology and Practice in Weiyuan Shale Gas Well at Low Pressure and Low Production Stage

Weiyuan shale gas well has the characteristics of high production and rapid decline in the initial stage of production. According to the production characteristics, it can be divided into three production stages:flowback after fracturing stage, rapid decline stage, low pressure and low production stage. There are obvious differences in production characteristics in different stages. At low pressure and low production stage, gas well production is low, pressure is low, decline rate is slow, production period is long, and production contribution reaches 60% . The production is easily affected by many factors, such as liquid loading of gas well, frac hit water flooding, system export pressure fluctuation, wellbore plugging and so on. It is the main stage for the implementation of stable production technology. In view of the factors affecting the production and different types of problem wells, technical countermeasures for stabilizing production of old wells with pressurization, foam drainage, plunger, gas lift,shaft cleaning and their combination has been innovatively formed. For instance, priority should be given to pressurization and foam drainage measures for wells with slight fluid accumulation, foam drainage or plunger technology is preferred for intermittent effusion wells, gas lift measures such as opening or closing wells are preferred for wells with serious fluid accumulation, wellbore cleaning or coiled tubing flushing shall be adopted for blocked wells, for water flooded wells with fracturing and channeling, priority should be given to synchronous depressurization gas lift, coiled tubing gas lift and displaced flow. Through the practice of stable production technology at low production stage, a special technical template is formed to effectively solve various production problems of gas Wells, maximize the production of gas Wells, improve the sustainable and stable production capacity of old Wells, and realize the efficient development of shale gas.