Reinjection Plugging Mechanism Researching Of Sedimentary Basin Type Porous Geothermal Water

The sustainable development of the deep pore sedimentary basin geothermal resource isthe key to solve the problem of energy tension and environmental pollution in our country, itis also a new topic involving multi-disciplinary and multi-field. The topic for research andengineering application is a new research field in China, there are a lot of frontier scientificissues to study. Reinjection to deep and geopressured-pore type stratum of sedimentary basinis hard to realize, which has become the key problem for sustainable development andutilization of thermal groundwater in sedimentary basin. The quantity attenuation of waterrecharge of deep pore type used geothermal water is the key technical problems of restrictingthe geothermal water reinjection. In this project, based on hydrogeochemical stimulation ofthe solution and precipitation tendency for different mines during water-rock interactionprocess between used thermal groundwater and medium in geothermal reservoir, blockingmechanism for used geothermal water reinjection was studied with the indoor cloggingexperiment, hydro geochemical simulation method and scene experiment of reinjection. Thestudy not only is very important, and is around the corner, has important theoreticalsignificance and practical application value.The paper takes deep geothermal water in the northwest town of Xi’an city which itssedimentary basin deep pore type geothermal water is rich, mines, the levels of geothermalwater falling faster and the used geothermal water to be reinjected. Under the geothermalgeological and hydrogeological conditions, using the method of combining theoreticalsimulation-indoor simulation-reinjection test, it takes the relationship between geothermalwater-used geothermal water reinjection-reservoir mineral-sediment and its transformationmechanism as the main line, studys the plugging mechanism simulation test of usedgeothermal water reinjection. Generally speaking,the main factors causing clogging duringreinjection are physic clogging, chemical clogging, gas clogging, microorganism clogging andcompound clogging. The purpose of the paper is to understand what is the main reason andsecondary reason for clogging of reinjection by used geothermal water. And throughcomparison and analysis of used geothermal water reinjection in Xianyang, the paper draws asuitability of injection tectonic units of deep pore geothermal resource in Guanzhong basin,deepen and enrich the understanding of the basic theory of the large rift sedimentary basin deep pore porous aquifer used water reinjection in China. It provides a demonstration of thetheory in sedimentary basin deep pore geothermal water reinjection and prevention andcontrol practices, provides a good example for future treatment of blocking problem in deepporous stratum in sedimentary basin, and furthermore, to offer the scientific basis forsustainable exploitation and utilization of the deep pore reservoir fluid.