The sand carrying capacity of heavy oil in horizontal well of loose sandstone reservoir

摘要

Based on the particle mechanics and fluid mechanics, using mechanism model of liquid solid two phase pipe flow, sand carrying mechanism model of heavy oil suiting for horizontal well have been established, which sand carrying capacity of heavy oil in horizontal wellbore were studied in this paper. The result show with the sediment of sand particles in horizontal wellbore bottom, cross-sectional area of wellbore flow reduces, the true liquid velocity increases. After reaching the steady state, sand particles are completely suspended, and the whole horizontal wellbore is the pattern which is inhomogeneous suspension layer in the top of the horizontal wellbore and fixed bed layer or flowing bed layer in the bottom. The heavy oil has limited capacity of carrying sand. At the same time, the height of fixed bed layer or flowing bed layer, the velocity of inhomogeneous suspension layer, the pressure gradient of horizontal wellbore change with the flowing velocity of the slurry of sand and heavy oil. With the decrease of the flowing velocity of heavy oil and wellbore pressure, the capacity of carrying sand decrease.