Solid-liquid Flow Law Of Horizontal Wellbore And Design Of Sand-carrying Production System

For the mining of sand-bearing reservoirs,moderate sand drainage and sand-bearing oil production are targeted and important solutions.The flow law of solid particles in the wellbore is one of the basic problems involved in the above-mentioned sand-carrying production process,and the sand-carrying flow rate is the main design parameter of the above engineering problems.At present,domestic and foreign scholars have studied more on the flow rate of sand carrying in vertical wells,but pay less attention to the variation law of sand carrying flow rate and its influencing factors in different dip angle sections in horizontal wells,and also ignore the different well sections of horizontal wells under the same conditions.Comparison of sand carrying capacity.Based on the above problems,the wellbore inclination angle is 0-90°,the fluid viscosity is 1-50 m Pa.s,the quartz sand and the ceramsite particle size is 0.015 mm,using the sandcarrying simulation experiment device for the whole-incline variation process of the wellbore from horizontal to vertical.The comparison of the flow rate of the wellbore carrying sand under the condition of 0.8mm and the inner diameter of the wellbore 40-100 mm obtained the sensitivity relationship between the flow rate of the sand and the fluid viscosity,particle size,particle density,and the inner diameter of the wellbore under different wellbore inclination angles.The experimental data were used to fit the empirical model of the sand flow rate of the horizontal section,the inclined section and the vertical section.The results show that for the medium coarse sand,the wellbore is at 0°,30°,45° under the same experimental conditions.The ratio of the flow rate of sand carrying at 75° and 90° is about 1.71: 3.35 : 2.86 : 2.28 : 1;for ultra-fine fine sand,the critical characteristic flow rate is very close,and the critical characteristic flow rate in horizontal section,inclined section and vertical section They are about 0.268,0.312,and 0.061 m/s,respectively.Based on the experimental phenomena and fitting results,the flow and method of correcting the current characteristic flow rate are given.Combined with the production conditions of an A well in an overseas oilfield,a reasonable sand carrying flow design is completed.