High Sulfur Content In Puguang Gas Reservoir Capacity Analysis Method Research And Its Application

With the increasing demand for natural gas. the proportion of gas reservoir with high content of H2S in the natural gas development is increasing.Gas reservoir with high content of H2S is very rich in china. The cumulative proved gas reservoir with high content of H2S has more than7000×108m3. accounting for about1/6of proved natural gas reserves. The gas reservoir with high content of H2S of carbonate rock in the domestic is still in early development stages. Puguang Gas Field, as the representative of high content of H2S of carbonate rock with burial depth, reservoir thickness, strong heterogeneity, with high content of H2S, with edge water etc,in which the production dynamic characteristics are more complex. In order to be able to efficiently mining and for the Puguang gas field and the surrounding block development to provide technical support and reference. The urgent work is to do in-depth research on well productivity evaluation method.The physical parameters of the reservoir fluid is the important parameters of gas reservoir engineering calculations. From the gas reservoir physical parameters calculations, the conventional calculation method of correction or improvement is suitable for the physical parameters calculation of the Puguang Gas Field. It will bring large calculation error used commonly Bruce E.Roberts model from sulfur solubility model.Using the measured data fitting model of Chrastil empirical formula and phase equilibrium solubility calculation is suitable for Puguang gas reservoir gas solubility prediction formula. Comprehensively considerated from simple and practical and calculation error two factors,it’s recommended using of empirical model for the prediction of the gas reservoir solubility. It’s seted up the sulfur deposition saturation prediction model respectively considering Darcy flow and non-Darcy flow and gived the example of calculation and analysis that the sulfur deposition mainly concentrated in near well within the range of1.5m. Respectively consider two aspects, the sulfur gas well deliverability equations are established. Apparent skin factor method and the two zone of the compound model of sour gas well productivity equation are binomial form.Adaption of conventional deliverability interpretation method is evaluated. On this basis, the Puguang gas field deliverability evaluation methods:Puguang improved one point method, wellhead pressure binomial method, formation coefficient method, yield ratio equation method, material balance and production method are established. Through a variety of methods compared, material balance and capacity method consider the effect of sulfur deposition and is a dynamic calculation of production process, which can reflect the production of the entire history, through the proceeds of the productivity equation A, B coefficients with pressure curves,the single well IPR curve, and the formation pressure curve,combined with actual output, flow pressure and calculation multi-objective function value of the output and flowing pressure fitting,single well production capacity under the current the formation pressure can be obtained.The calculation results can be getted the reliability and accuracy. Finally the new method on33single well productivity calculation for gas wells was carried out, the reasonable gas production were evaluated with oil pressure change on gas well.