Research And Application Of Oil-based Drilling Fluid System With Low Oil To Water Ratio

In the drilling process,the oil-water ratio of oil-based drilling fluids currently used is generally high,usually up to 85/15.Therefore,these oil-based drilling fluids have high cost and strict preparation conditions.If water intrusion occurs,it is extremely easy.Affect the performance of the system,which may lead to fires caused by leakage of volatile substances.Therefore,for the on-site construction requirements,this paper proposes a low oil-water ratio oil-based drilling fluid system,which is the basis for the formation,thermodynamic properties,physical properties,rheological properties and interfacial properties and mechanism of the water-in-oil emulsion.The treatment of low oil-water ratio oil-based drilling fluid system,such as emulsifier,fluid loss additive,organic soil,etc.,is determined to determine a low oil-water ratio oil-based drilling fluid system formulation,and low oil-to-water ratio oil In the base drilling fluid system,the water phase content is greatly increased,and the performance of the system will be affected.In order to enable it to be put into application,various properties such as temperature resistance,inhibition performance,anti-pollution performance,etc.The settlement stability,pressure bearing capacity and leakage prevention ability were evaluated,and good results were obtained in the indoor evaluation process.The research contents are as follows:1)According to the analysis of the formation of water-in-oil emulsion,the effective components of the stable water-in-oil emulsion are determined.On the basis of this,the properties of the drilling fluid and various mechanisms of action are studied,including the system.The stability mechanism,the fluid loss mechanism,and the lubrication mechanism were evaluated for the treatment agent preference and performance.1)When constructing a low oil-water ratio oil-based drilling fluid system,the type and amount of emulsifier,fluid loss additive,organic soil,wetting agent and alkaline regulator in the drilling fluid system were mainly carried out.Preferably,the basic formulation of the system is thus determined.3)Based on the basic formula of the oil-based drilling fluid system with low oil-water ratio,the indoor temperature resistance,inhibition,pollution resistance,sedimentation stability and wellbore pressure capacity were evaluated.The effect required by the site has been achieved.Considering the low oil-water ratio of the drilling fluid system studied in this paper,it may affect the leakage accident during the operation.Therefore,the article finally evaluates the plugging and sealing ability of the plugging effect.good.4)For the field application of low oil-water ratio oil-based drilling fluid in two wells of Jiaozuo Formation,it is found that the low oil-water ratio oil-based drilling fluid system has no rheological instability,leakage and wellbore collapse in the application process.The drilling fluid has maintained excellent performance during the drilling maintenance process,which provides a good guarantee for the smooth construction of the drilling.Through the research on oil-based drilling fluid system with low oil-water ratio,the blank of low oil-water ratio oil-based drilling fluid in oil-based drilling fluid is further filled,and it provides reference and reference value for the further development of oil-based drilling fluid.