Experimental Study And Mechanism Of Reservoir Damage In High Temperature And High Pressure Gas Reservoirs

High-temperature and high-pressure gas reservoirs are widely distributed and large in China.The reservoir damage caused by pressure failure and seepage process in high-temperature and high-pressure gas reservoirs has caused adverse effects on plugging reservoirs and reducing gas well productivity.The high temperature and high pressure gas reservoirs in the yingqiong basin are the research objects.The modern experimental analysis methods are used to make full use of the theory of seepage mechanics and well test analysis to complete the reservoir damage experiments and mechanism research in high temperature and high pressure gas reservoirs,and the salting out and scaling are obtained.Damage to the reservoir due to factors such as water lock and stress sensitivity.At the same time,the reservoir damage assessment method caused by pressure failure and seepage process in high temperature and high pressure gas reservoirs is obtained.Based on a large number of literature research,the main research contents of this paper are as follows:(1)Study on the relationship between reservoir rock stress change and rock characteristics;(2)Study on the original occurrence state and output capacity of reservoir water in high temperature and high pressure gas reservoirs(3)Study on gas-water two-phase seepage characteristics under high temperature and high pressure gas reservoir conditions;(4)Evaluation of salting out damage in high temperature and high pressure gas reservoirs;(5)Evaluation of reservoir fouling damage in high temperature and high pressure gas reservoirs;Research on water lock damage evaluation of high temperature and high pressure gas reservoirs;On the basis of summarizing and absorbing the relevant experiments and research results of yingqiong high-temperature and high-pressure gas reservoirs,the high-temperature and high-pressure core multi-parameter measurement system and the core experiental device are used to select different physical cores and comprehensively analyze different pore structures.Under the relationship of pore throat,the water occurrence state of different reservoirs under different displacement pressures,the distribution of gas and water in microscopic pore throat and the mobility of water,study the pore throat related parameters and water occurrence state.The relationship between the relationship and physical properties on reservoir bound water and mobile water saturation.By comparing dry core,water-bearing core and polluted core,the permeability damage assessment is carried out to study the damage law of salting,scaling and water lock on the reservoir.Through the above research,the reservoir damage assessment method caused by the pressure failure and seepage process in high temperature and high pressure gas reservoirs is formed.