大张坨地下储气库井口温度影响因素

大张坨地下储气库是保障河北及京、津地区天然气调峰需求和安全供气的基础设施。为了防止地下储气库气井天然气水合物的形成，结合Ramey和Alves关于井筒流体温度计算的方法，从流体与环境之间的热传递和流体自身性质发生变化两方面的影响因素出发，综合应用能量守恒、传热学以及热力学，从而得出大张坨储气库井筒流体温度计算模型。同时应用得到的数学模型，研究了大张坨储气库气井井口温度影响因素，并掌握了井口温度的变化规律。结果表明，井口温度在开井初期迅速上升，然后逐渐达到稳定；不管是在开井初期还是在井口温度达到稳定时，产气量和地温梯度都是影响井口温度变化的主要因素；生产气液比和井身结构对井口温度略有影响；由于井筒热阻的存在，在开井初期井口温度的变化与地层导热系数无关，当开井达到稳定时，地层导热系数越大，井口温度略有降低。

ANALYSIS ON EFFECTING FACTORS OF WELLHEAD TEMPERATURE FOR DAZHANGTUO UNDERGROUND GAS STORAGE 1)

To prevent forming hydrate in the gas wells of Dazhangtuo underground gas storage, with Ramey and Alves temperature calculatin g methods of borehole fluid, according to the effecting factors from the 2 chang es of the heat transfer between fluid and environment and the fluid own property , comprehensively applying energy conservation, heat migration and thermodynamic s, the temperature calculating model of borehole fluid is developed for Dazhangt uo underground gas storage. With the mathematical model, the effecting factors o f wellhead temperature are studied and the changing law of wellhead temperature is known for Dazhangtuo underground gas storage. The results show the wellhead t emperature rises rapidly at the early stage of well opening and then reaches sta bility gradually. However, the gas production and the geothermal gradient are th e main factors to influence the change of wellhead temperature whatever at the e arly stage of well opening or the stable period of wellhead temperature. The gas /liquid ratio and the well-bore structure only have a little influence on the w ellhead temperature. The wellhead temperature changing is not related with the t hermal conductivity of the formation at the early stage of well opening. When th e wellhead temperature reaches stability, it reduces a little as the thermal con ductivity of the formation increases.