Analysis Of Production Decline And Study Of Mitigating Decline For Low-Permeability Reservoir

The research on production decline law is one of important content in reservoir dynamical management. During the exploration and development of low permeability reservoir, the analysis of production decline becomes more and more important, and the study is more completely than ever before. Aimed at decline law and the technology for slowing down production decline, the theses did some research work based on reservoir geology and reservoir engineering, used geological description and mathematical analysis, and did numerical simulation. The theses included some contents as following:1. The theses studied of geological and development characteristics in low permeability reservoir. Low permeability reservoir has features of low porosity and low permeability. In addition, the important factors that influent development effect include different sedimentary facies, high heterogeneity and fracture. The theses analyzed the relationship between geological characteristics and dynamical development characteristics by related data. The theses calculated individual well recoverable reserves and evaluated development effect by decline equation, water drive curve, and model prediction.2. Composite declining could not accurately reflect the production decline after compared natural decline and composite decline. The theses established new thought based on analysis of natural decline, and analyzed transient decline by dimensionless average daily production.3. Deeply studied decline law after dealing with production data and dividing decline process. The theses used new thought to studied composite declining, natural decline, and well production changes. The researcher collected development information of domestic and abroad low permeability reservoir and compared studying area. Based on these, it studied prediction equation of water-cut and liquid-producing capacity.4. Established geological factors analysis method of decline by studying producing effect from sedimentary facies, heterogeneity, fracture, and interlayer distribution. Compared decline law in different sedimentary facies, and heterogeneity reflected decline. Derived weight analysis equation on the basis of yield component and analyzed decline factors. Sorted decline factors by grey correlation theory. The point of weight analysis was evaluation importance of decline factors among producing process. Grey correlation theory sorted decline factors by making producing as a whole.5. Studied development technologies from flooding parameters optimization, injection-production system adjustment, and well pattern thickening. And then, it optimized technologies by reservoir engineering and numerical simulation.The theses widened and developed study method of production decline law and analysis method of effect factors through studied. The research results have certain theory value and application prospect, and supply study thought of development evaluation and adjustment for low permeability reservoir.