The Fracturing Fluid For Artificial Fracture Injury Evaluation And Factor Experimental Study Of Low Permeability Reservoir

In this paper, Have the M ultra-low permeability- tight oil reservoirs for the study, on the basis of reservoir rock and fluid properties comprehensive research study of the M reservoirs and indoor sensitivity analysis, with real sandstone microscopic model to study the cake artificial crack microscopic mechanism of injury; while established a fracturing fluid to hydraulic fracture evaluation of core damage experimental methods to study the factors, and the damage fracturing fluid system for artificial fractures were evaluated; Used this method Guar gum fracturing fluid produced by the extent of the damage and influencing factors were studied artificial fractures in the study area. This paper achieved the following results and understanding:(1) The main reservoir rock types in the study area is the lithic arkose, feldspathic sandstone and feldspathic lithic sandstone reservoir rock with fine sandstone, siltstone followed; cement content, water mica, ankerite, chlorite reservoir rocks is the main cement. Fracturing fluids for artificial fractures potentially major damage are: cake residue, fines migration, water sensitivity, water lock, acid sensitivity.(2)The three commonly used artificial fracture damage fracturing fluid is different in study area. At reservoir temperature, thickening water damage to the crack is relatively large, with an average of 27.1 percent injury rate, guar gum and PPQ system were 26.3% and 20.7%; thickening water damage because of cracks at reservoir temperature and reservoir rock some adverse reactions occur, resulting in crack surface mud and fines migration, thereby reducing the penetration of cracks rate; guar gum and PPQ system in the formation of cracks in the surface of the artificial cake, causing artificial fracture injury.(3) The viscosity of the fracturing fluid cake will increase stuck in the cracks in time increases, it is artificial fracture core damage rate increases; different fracturing fluid forms cake are different, have a certain impact on injury rates.(4) The guar gum fracturing fluid cake has significant relationship in artificial cracks injuries and broken glue viscosity. In this paper, no sanding artificial fracture injury evaluation experiments showed that the maximum viscosity guar gum fracturing fluid average damage rate of 82.09%, while the lowest was only 37.5%.(5) After sanding artificial fracture, guar gum fracturing fluid for sanding artificial fractures increased core damage; crack surface roughness greater the initial penetration is higher, artificial fracture injury rate is comparatively small; artificial fracture injury rate increases back to the displacement was decreased, and gradually stabilized.(6) Using artificial crack evaluation crack damage degree of fracturing fluid is a viable approach. In this paper, from a large number of experimental studies, established core evaluation methods and procedures of a fracturing fluid artificial fracture, and to determine the experimental conditions and specific experimental parameters boundaries.