Abstract: In the previous studies, the data of the high sulfur gas reservoir development research are difficult to obtain in the actual operation. Considering sulfur deposition near wellbore, the mathematical model of production decline in sulfur deposition composite gas reservoir is established. The production decline Blasingame type curves of single gas well in high sulfur gas reservoir are drawn with Stefest numeric inversion. Then, the characteristics of curves and influence factors are discussed. The non-dimensional production decline integral derivative curves concave down deeper at middle period of production decline curves with the growth of sulfur saturation. When the sulfur saturation increases to 50%, the integral derivative curves sink to the deepest level and the integral derivative value is minimum. The smaller the radius of sulfur deposition is, the earlier the flattish stage of the non-dimensional
production decline curves will appear. A straight line with slope of -1 is emerged in both the integral and integral derivative curves at late period of the production decline curves, which is the indication of harmonic decline. The
study findings are superior to the pressure build up test, therefore, this study is of great value in the exploration and development of gas reservoir with high sulfur.

Key words: high sulfur, sulfur deposition, production decline, Blasingame curve, production performance