Application Of Cross-linking Acid Fracturing With Proppant Technique In Redevelopment Of Dolomite Reservoirs

In recent years, dolomite gas and oil reservoirs were being placed on productionone after another through exploration in China. Most of these reservoirs displayed thecharacteristics of deeper burial, lower permeability, better developed naturalmicrofractures, further stubborn vertical heterogeneity, higher bursting pressure andclosure stress, more difficult exploitation, and lower level of producing reserves. Soacid fracturing techniques have become one of the main measures of bring intoproduction in these dolomite reservoirs. In order to improve the development benefitsof these lower permeability reservoirs, this paper has carded the pilot tracey of newindependent-developed cross-linking acid fracturing with proppant on well site, on thebases of summarizing and analyzing the outcomes of predecessors, after some relatedlaboratorial experiments and demonstrations of related theories. This technique hasacquired good effects in redevelopment of dolomite reservoirs of JingBian Gas fieldof ChangQing. Besides, this technique has probed the practice of acid fracturing withproppant technique. By this paper, the main recognition can be concluded asfollowings:(1)This paper has tested the actions of kinetics of reaction between the newcross-linking acid and dolomite rocks, and acquired the related dynamic parametersand equations.(2) In view of the problems of filtration in dolomite reservoirs, this paper hasconsidered the effect of wormholes in course of acid corrosion on the bases ofanalysis of traditional filtration mechanism in limestone reservoirs. And finally, thispaper has rectified the synthetical filtration parameter.(3)This paper has operated the synthetical analysis of proppant-carrying theoryand related laboratory experiments and evaluations.(4)This paper has carried the synthetical analysis and evaluations on the effects of new independent-developed cross-linking acid fracturing with proppant techniquefor the first time, which aimed at the domestic low permeability dolomite reservoirs.Therefore, the new technique mentioned in this paper, not only as the guidance tothe stimulation and stable yields of treating regions, but also played an important rolein reservoir reform of other dolomite (and limestone) areas, from which draw thelessons.