钻井液与砂岩混合产气模拟实验研究

Study of mixed gas production simulation test for drilling fluid and sandstone

为了验证在高压环境下井筒钻井液及岩屑是否产气,及对气测录井是否产生影响,选择4种常用的钻井液和海拉尔盆地6块不同深度、不同层位砂岩,在100℃、150℃温度条件下分别进行4种钻井液及其与砂岩混合物的模拟加热实验。结果显示,常用的4种钻井液在低温时基本不产气,高温时均产气,温度是影响其受热产气量的主要因素;产出气中以非烃气为主,钻井液类型是影响产出气中N2和CO2含量的主要因素;当地层温度较高时,存在钻井液受热产出CO2并对气测录井产生影响的可能。

In order to verify whether wellbore drilling fluid and cuttings produce gas or not and influence gas logging under the high pressure environment,four types of common drilling fluid and six lumps of sandstone from different depth and horizons from Hailar Basin were selected,the simulation test for the mixture of respective four types drilling fluid with sandstone were made under the temperatures 100℃ and 150℃. The results showed that the conventional four types of drilling fluid basically did not produce gas under the low temperature instead of producing gas under the high temperature,the temperature was the main element that affects how much of gas would be produced,the producing gas was the dominant non-hydrocarbon gases,the type of drilling fluid is the main element of affecting N2 and CO2 content in producing gas. When the formation temperature is high,CO2 will be produced as the drilling fluid is heated,which exerts effects on gas logging.