Liquid sulfur condensate phenomenon exists in ultra-deep sour gas reservoir

which affects the reservoir permeability and reduce the gas well productivity.A numerical simulation model proposed in this paper for sour gas reservoirs considers such a two phase flow with both liquid sulfur condensate and gas fluids.On basis of the model

a numerical simulator is developed and used in research of sour gas well production.The results shows liquid sulfur mainly gathers near wellbore

and never extend further during the entire production life.Compared with solid sulfur deposition

condensation of liquid sulfur has less effect on the gas well production.However

the peak production period of gas well reduces obviously.In heterogeneous formation

the liquid sulfur mainly gathers where better reservoir property is present.The liquid sulfur preferentially occupies high permeability zones such as fractures or vugs

which leads to reservoir permeability reduction and the well production decline.Based on this technology

the liquid sulfur condensate behavior in sour gas reservoir can be predicted quantitatively.Thus the technology can provide reliable results for decision-making.