Fracturing Optimization Technology For Tight Sandstone Reservoir Of Surig

Surig gas field is in a typical low permeability, low pressure, low abundance of the "threelows" field.Therefore fracturing transformation as a means of effective development of lowpermeability gas reservoir and widely applicated.In the actual fracturing process, newtechnology and new fracturing material have been used.How to form suitable fracturingtechnology for tight sandstone reservoir becomes an urgent problem.Basis on statistics and researching about the dense sandstone reservoir parameters, fromthe macroscopic structure characteristics and sedimentary characteristics to microscopicdiagenesis, pore permeability, clay minerals and micro pore structure characteristics, analyzedthe effect to the reservoir characteristics of fracturing.Thinking in that nose structure don’tdirectly influence on oil and gas gathering, but the property at low point of nose structure isgood, is conducive to improve the effect of fracturing; On the center of the beach atmosphereof sedimentary microfacies, fracturing effect is good. East of the reservoir in a quartzbrittleness and mineral content under the influence of diagenesis content decreases, thereservoir more dense, influenced and restricted the fracturing effect;The porosity from8%to10%, the permeability from0.4to0.8×10-3μm2reservoir, gas well fracturing effect isbest;Compared with the central gas field of Surig,the east field in a higher clay mineralcontent in the reservoirs, the porosity and permeability, water sensitive damage can easilycaused by fracturing process;East is mainly in a complex pore structure, a large number ofnative gap loss, secondary pore development, pore connectivity is poor, seriously restrictingthe fracturing effect. On this basis, the corresponding hydraulic jet for horizontal well stagedfracturing and open hole packer staged fracturing technology, applied on vertical Wells,directional well casing sliding sleeve layered fracturing packer multilayer fracturingtechnology is optimized, and determine the various technology construction under the condition of displacement, sand ratio and pump injection procedures, etc.Under laboratoryconditions, in accordance with the relevant experimental standard evaluation of a newfracturing fluid and proppant, the best fracturing fluid is chemical system, then is Jia Yisystem, Jiang Han system is worst;Chemical system is suitable for horizontal well fracturing,Jia Yi system is suitable for vertical well and directional well fracturing;Propping agentsystem, in the high closure pressure formation, should choose small particle size: the40/70orders YuanQu corundum proppant;acid in a bottom water or edge water underlyingconditions, should choose20/40mesh tongchuan Qin Han proppant.