盐穴储气库地面工程技术要点研究

Key Point Study on the Surface Engineering Technology of Salt Cavern Gas Storages

金坛储气库是我国仅有的1座已建成投产的盐穴储气库,对其设计、建设和运行经验进行总结,可为平顶山和淮安等盐穴储气库的建设设计提供指导。盐穴储气库是利用地下已有的盐层,采用人工的方式在盐层中水溶形成腔体,用于天然气回注、储存和采出的系统体系。盐穴储气库地面配套工程须额外增加造腔地面配套系统和注气排卤系统;注采气工艺中压缩机的选型也须兼顾注气排卤工况;盐穴采出气含有卤水,且各腔体独立,压力会有所不同,采气脱水工艺须能够适应腔体温度、压力变化。处理装置设计规模须根据盐穴储气库的功能定位、注采周期和注采能力等因素确定。多级离心泵作为造腔注水泵是最适宜的注气排卤设备,可满足各种工况条件下的快速造腔和盐厂的卤水回收要求。采出气处理工艺的选择须避免水合物生成并合理地控制水露点,三甘醇脱水和J-T阀+乙二醇技术是常用的脱水工艺。压缩机厂房的降噪是储气库建设的重要设计之一,采用吸声、隔声、隔振和通风消声等噪声控制措施可以实现整体降噪的目的。

Jintan Gas Storage is the only salt cavern gas storage that has been built and put into production in China.The design,construction and operation experiences are summarized to provide guidance for the construction design of other salt cavern gas storages such as Pingdingshan Salt Cavern Gas Storage and Huaian Salt Cavern Gas Storage.The salt cavern gas storage is a system that utilizes existing underground salt beds to form caverns in salt beds by the water-soluble artificial method and is applied for natural gas injection,storage and recovery.The gas injection and brine discharge as well as cavity making system should be added to the surface supporting system of the salt cavern gas storage.The selection of compressors in gas injection and production process should also take into account the working conditions of gas injection and brine discharge.Salt cavern produced gas contains brine,and the every chamber is independent,so their pressure will be different.The gas production and dehydration process should be able to adapt to the temperature and pressure changes of the chambers.The design scale of the processing device should be determined according to the function orientation,injection-production cycle and injection-production capacity of the salt cavern gas storage.The multi-stage centrifugal pump,as the water injection pump for cavity making,is the optimal device for gas injection and brine discharge,which can meet the requirements of rapid cavity making and brine recovery in salt plants under various working conditions.The treatment process for produced gas needs to avoid hydrate formation and control dew point reasonably.Triglycol dehydration and J-T valve+ethylene glycol technology are commonly used dehydration processes.The noise reduction of compressor workshops is one of the important measures in the construction of gas storages.Noise control measures such as sound absorption,sound insulation,vibration isolation and ventilation noise elimination can be used to achieve the overall noise reduction design.