Design And Performance Analysis Of Surface Jet Sand Mixing Device For CO₂ Fracturing

Sand fracturing is widely used in the development of low and ultra-low permeability oil fields and stimulation of production Wells as a kind of reservoir permeability improvement.Sand mixing as an important part of sand fracturing operations directly affects the quality of sand fracturing.As the most widely used sand mixing equipment in oil fields,the sand mixing truck has many problems,such as equipment redundancy,poor adaptability to complex terrain,high failure rate,difficult maintenance,complex operation and so on.In order to solve the above problems,this paper designed a kind of ground jet sand mixing device and a kind of atmospheric ground sand adding device,which can replace the sand mixing car for sand mixing operation,has the characteristics of simple structure,strong adaptability to multi-terrain,simplified ground equipment,reduce the cost of sand adding fracturing.The main research contents of this paper are as follows:(1)Based on the research of domestic and foreign literature,this paper introduces the fracturing stimulation process and development status,and summarizes the technical characteristics of carbon dioxide sand fracturing and its field application.(2)A kind of jet sand mixing device based on the jet principle is designed,and the structure of the device is designed and optimized.(3)Based on the supporting requirements of the jet sand mixing device,an atmospheric pressure sand feeding device is designed,and its connection mode and component layout are described.(4)SolidWorks software is used to model the flow channel of the sand mixing device,and Fluent software is used to carry out numerical simulation of the designed sand mixing device.The research results show that the structure of the 45° double sand feeding pipe has a positive effect on the improvement of the sand mixing performance of the device.When the nozzle diameter is 13 mm,the throat diameter is 22 mm,the throat length is 90 mm,the throat distance is 160 mm,and the diffusion Angle is 7°,the sand mixing performance of the device is relatively best.(5)Structures,jet sand mixing device for test bench,the carrying capacity of the jet sand mixing device indoor experimental research,the study of the smaller size range of nozzle diameter,jet sand mixing device of the stronger proppant carrying capacity,when the throat mouth distance is 150 mm,the carrying capacity of the strongest jet sand mixing device,and presumably when throat mouth distance from 150 mm reduced constantly,Sand carrying capacity of the device is bound to appear an inflection point.