METHOD FOR DETERMINING CHANGES IN THRESHOLD FILED OF ROCK SPECIMEN IN ACID COMPOUNDS Russian patent published in 2002 - IPC

FIELD: inspecting rock-container forming pay sections in acid treatment area. SUBSTANCE: specimen is saturated with strata water, weighed out, centrifuged, weighed out after each cycle, and initial pore size distribution histogram is constructed. Specimen is saturated with kerosene in vacuum, placed in specimen holder of device simulating strata conditions, and kerosene penetrability is determined. Acid compound is injected, then injection is ceased to allow specimen to enter in reaction with acid for an hour, specimen is washed out with kerosene to remove remnants of reaction at pressure equal to depression at well management. Kerosene permeability is determined, specimen is removed from specimen holder, extracted with alcohol-benzene mixture, dried out at 105 C, weighed out, saturated with strata water in vacuum under same conditions, final pore size distribution histogram is constructed, data of initial and final histograms are compared, and amount of pores dissolved by acid compound is counted using known method. EFFECT: provision for determining degree of acid compound reaction with threshold field of rock-container to enhance productivity of wells.