蜀南地区煤层气智能精细化排采技术及管控模式

Intelligent and fine CBM production technology and management & control mode in South Sichuan area

煤层气井的产出机理决定了其生产方式必须通过排水降压,排采是煤层气开发中十分重要的环节。四川盆地蜀南地区煤岩具有高煤阶、高临界解吸压力、低渗透的特征,规模效益开发面临着巨大的挑战,先进的排采技术与智能精细化管控模式是实现该区域煤层气规模、经济开发的保障。中国石油浙江油田公司在蜀南地区从事煤层气开发近五年,通过引入排采规律指导下的智能排采专用设备,落实煤层气"连续、稳定、缓慢、长期"的排采原则和精细化排采技术路线,针对煤储层特点及煤层气井生产规律,精细划分为排水降压期—憋压期—控压提产期—稳产期—产量递减期等5个排采阶段,系统分析各阶段生产特征及排采风险,总结出了"五分技术攻关、三分管理创新、两份多专业融合"的煤层气管控模式,制定出合理的排采制度和管控办法,并依托智能化设备,实现了精细排采管控,从而降低了储层伤害、提高了单井产量、提升了管理效率、促进了该区煤层气的高效开发。

The production mechanism of CBM wells allows them to be recovered by water drainage to reduce the pressure, so the recovery by water drainage is an important part of CBM development. The coal rocks in South Sichuan Basin are characterized by high rank, high critical desorption pressure and low permeability, bringing huge challenges to the large-scale beneficial development. Advanced production technologies and intelligent and fine management ＆ control mode are the basis of large-scale economic develop- ment of CBM in this area. PetroChina Zhejiang Oilfield Company has carried out CBM development in South Sichuan area for nearly five years. The ＂continuous, stable, slow and long-term＂ CBM production principles and the fine production routes are implemented by adopting the specific intelligent production equipment. Based on the characteristics of coal reservoirs and the production laws of CBM wells, the production was divided into 5 stages, i.e., pressure reduction by draining water, pressure building up, production in- creasing by controlling pressure, stable production, and production decline. The production characteristics and risks in each stage were analyzed systematically. The CBM management ＆ control mode of ＂50%0 technology research, 30% management innovation and 20% multi-discipline integration＂ was established. Rational production systems and management ＆ control methods were formulated. By virtue of intelligent equipment, precise management and control over production by water drainage was realized. All these measures are designed to reduce reservoir damage, increase single-well production rate, improve management efficiency, and promote high-effi- ciency CBM development.