中低渗枯竭气藏改建地下储气库难点及对策

枯竭油气藏是改建地下储气库的最佳类型，但在天然气用户区域，很多中低渗枯竭油气藏的储层条件不够理想。中低渗枯竭气藏改建储气库存在气井单井产能低、储层改造难度大、有效期持续时间短等难点。针对上述问题，在中低渗枯竭气藏改建储气库时，采取的主要措施是提高垫气比例，控制水体的侵入，利用水平井注采提高单井注采气能力，采用欠平衡钻井等方式加强储层保护，并且避免利用中低渗储气库进行日调峰，尽量使储气库的调峰平稳运行。通过这些措施，中低渗枯竭气藏改建储气库基本上可以满足局部地区季节调峰的需要。

Difficulties and measures in reconstructing underground gas storages based on medium to low permeability depleted reservoirs

The depleted reservoirs are best sites for reconstructing underground gas storages (UGS). However, in natural gas consumption area, there are a lot of depleted reservoirs with medium to low permeability. There are some difficulties in reconstructing the UGS under this situation, including low production capacity for an individual gas well, high reservoir reconstruction difficulties, short effective duration, etc. In view of these problems, some major measures should be taken, including boosting cushion gas proportion and controlling aquifer water inflow, utilizing horizontal wells to enhance gas injection and production capacity, strengthening reservoir protection through underbalanced drilling, avoiding using medium to low permeability reservoirs for daily peak shaving and maintaining sustainable peak shaving. Via these measures, UGSs which are reconstructed based on medium to low permeability reservoirs can basically meet seasonal peak shaving requirement in some local areas.