| Dazhangtuo Gas Storage is the first gas storage constructed on a condensate gas reservoir in china, which would be helpful to meet the need of stable natural gas in Beijing and Tianjing, is an organic part of long-distance pipeline from Shanxi to .Beijing. But how to construct a high efficient and safe gas storage, there are many technical problems that need quantitative or semi-quantitative conclusions trough simulation technique. According to the well-known advantages of simulation technique, it would be a necessary mean in the research of Dazhangtuo gas storage.The thesis would describe the research and results through simulation as far as some concerned problems, at the same time, it is the first to use 3D multi-component model to research Dazhangtuo Gas Storage too. The steps in this simulation study is as follows: First, taking advantage of the latest geological research results and combining with fluid properties research results ; secondly, selecting the right mathematic model, a good software GEM from CMG company and developing virtual well technique; thirdly, setting up the more real geological model trough history match. Fourthly, researching working mechanism of gas storage, analyzing its sensitivity, simulating its performance process, optimizing its design parameters. Finally, recommending the optimized plan combined with the need of market, and predicting the indexes.Through the above research, the following conclusions could be drawn: first, adopted the latest geological research results and combined with original components research of condensate gas, the geological model is reliable through history match. Secondly, the stable boundary problem of gas storage has been successfully resolved through the developed virtual well technique. Thirdly, When the pressure range ofDazhangtuo Gas Storage is between 29Mpa and 15MPa, the maximum reserve is 16.84 ×108m3, the basic reserve is 9.94× l08m3, and the available reserve is 6.9×108m3. Fourthly, Condensed liquid around well-bore will affect the production of gas well. With the quantity of condensate liquid increasing, the production of gas well would decrease sharply. With the period of gas storage working, the injected dry gas would lighten theformation fluid step by step, as a result, the production capacity of single well would increasing gradually. Fifthly, the edge water energy of Dazhangtuo condensate gas reservoir is not enough to influence the construction of gas storage. In order to decrease the influence of edge water and prevent trip gas, the distance from the new well sites to gas-oil boundary should be more than 200 meters. Sixthly, the ability of gas storage to meet an emergency or requirement is different at different pressure. The gas production rate could be 910 × 104m3/d or more if the reservoir pressure were more than 28Mpa during the preliminary period. Seventhly, the working course of gas storage would enhance condensate oil recovery largely. Eighthly, the recommended plan of gas storage is as follows: the total number of gas wells is 16, among which 8 wells would be used to injector during the gas-injection period, and the working pressure range would be from 16.5 to 28MPaSimulation conclusions have been adopted in Dazhangtuo Gas Storage Project. Since the gas storage had been finished, it had provided natural gas 9780 × 104m3 for Beijing first at the winter of 2000, during which period the maximum gas quantity is 311.9 × 104m3/d and the average quantity is 34.6 × 104m3/d provided by single wells. The facts have proved that the simulation study is useful and successful, at the same time it realizes the goal to provide the scientific evidence to construct a high efficient and safe gas storage.
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