PROCEDURE FOR DETERMINATION OF CRITICAL RATES OF FLUID Russian patent published in 2011 - IPC G01N15/10 

FIELD: gas-and-oil producing industry.

SUBSTANCE: procedure for determination of critical rates of fluid corresponding to beginning of sand production from porous samples of rock consists in purging fluid free from particles through porous sample of rock and in production collecting. Also, compressed fluid is purged through a porous sample of rock. Purging is performed in several stages with more and more increasing consumption of fluid and at constant time spent for each stage. Upon each stage completion there is calculated amount of evacuated particles of various cross dimensions. There are plotted graphs of dependence of amounts of evacuated particles with certain cross section on consumption of fluid on base of obtained results. Further, critical consumption corresponding to beginning of production of particles of certain cross section is found on base of graphs. There is plotted a graph of dependence of critical consumption on dimension of particles and there is calculated critical rate of fluid by formula: where ν is critical rate of fluid corresponding to beginning of production of sand particles of certain dimension out of porous sample, m/s; q is critical consumption corresponding to beginning of production of particles of certain cross section, m³/s; m is porosity of rock sample; S is area of cross section of rock sample, m².

EFFECT: determination of critical rates of well compressed fluid corresponding to beginning of sand production from porous samples for evacuated particles of different dimensions.

6 dwg