Study On Optimization Of Fracturing Parameters In Karamay Gas Field

The Karamay gas field is a low-porosity and ultra-low permeability reservoir with high level of heterogeneity and poor pore type.At present,it has experienced the end time of stable production,the production of old wells is declining with lower the production of new wells.The bottom water is active,and the investment income deficit is severe.How to develop new wells cost-effectively is a serious problem.In order to solve the problem on the spot,this paper mainly focuses on the DX14,DX17 and DX18 well areas,and carries out research on the stimulation and stimulation technology of gas reservoirs.Based on the statistics and research on reservoir physical parameters,the effects of clay mineral composition,fracture development characteristics,sensitivity and geostress characteristics on fracturing transformation were analyzed.It is believed that there is potential for water sensitivity in reservoirs;reservoir fractures are unevenly distributed,and natural cracks account for 80%of crack types.The reservoir is moderately strong-strong water sensitive,medium strong-strong speed sensitive,strong-extremely strong acid sensitivity.The upper part of the partially fractured well layer has no shielding layer,and the crack easily extends upward.Through the evaluation of the construction of the old well fracturing in the early stage,the main influencing factors of different types of reservoir construction pressure variation characteristics and the small length of the fracture crack and the low conductivity are revealed.Based on the characteristics of volcanic reservoirs,the fracturing design software was used to invert the formation parameters to correct the formation permeability.It was found that the true permeability is higher than that of the laboratory evaluation,and thus the geometrical size and scale of the hydraulic fractures and the cracks.Optimization of support length,sanding scale,construction parameters and other indicators.New fracturing fluid systems and proppants were evaluated under laboratory conditions in accordance with relevant experimental standards.It is clear that when the ratio of 20-40 mesh and 30-50 mesh proppant combination is 2:1 and 3:1,the conductivity of the proppant crack is stable;the CMHPG system fracturing fluid has delayed crosslinking time and temperature resistance.The comprehensive performance of shearing,viscoelastic properties,proppant settling and gel breaking performance is better.