Hejian Dongying Formation Oil Reservoir Depth Of The Ministry Of Acidification Research

Sandstone matrix acidizing is one of the main technologic measures applied in pressure release and augmented injection in water-injection wells.The flow and reaction of acid in the intercrystalline,pores and microcrack, the reaction between acid and bulkhead can lead to resolving particle, contaminant which are produced from well drilling, completion, workover in the formation near well bores.Then, damage to formation permeability is relieved, filtering passageway of fluid is dredged so as to recover and enhance injection capacity.According to statistics of home and abroad,there are many technologic measures applied in pressure release and augmented injection in water-injection wells,oil wells such as water packing off, paraffin removal and control, formation solid control,however, acidizing and fracturing are the most effective way.Hejian Dongying reservoir water injection development in the long run, the injected water damage exogenous and endogenous damage continued to promote the formation of deep and deep in the strata accumulated, Conventional pre-acidification measures, only to lift superficial strata of pollution, acidification are not ideal. Therefore, the lifting of deep formation pollution, restoration of ground water absorption capacity, to maintain balanced injection, become urgent problems.Based on the Hejian Dongying Reservoir Characteristics, rock mineral composition, over the years on measures, such as static and dynamic data analysis, and combined with laboratory and field practice reveal the factors causing formation damage, thus Defined measures of deep acidification program, and designed multi-hydrogen acid system. By means of testing of the reservoir rock resolution experiments, selection and appraise of acid additives and the appraise to the overall performance of acid formulas to determine a basic formula multi-hydrogen acid. Long core acidizing flow simulation results show that the acid system applies to Hejian Dongying reservoir, acidizing good effect. The acid system to multi-level multi-ionization of organic acids as the major component acid solution, with good retarded properties and Fe3+, Ca2+, Mg2+, Ba2+ chelating properties of the plasma is better to solve the secondary precipitation problems after acidification.Using the deep acidizing technology, between J127, J157 two wells on the field test conducted. Measures two wells, water pressure is reduced, formation water absorption capacity increased, injection profile is greatly improved, corresponds well to achieve output, measures the success rate of 100%.The research of this paper have reference value to other similar sandstone reservoirs to solve the problems of water injection pressure reduction and injection increasing.