Sulfur deposition in the formation, induced by a reduction in the solubility of the sulfur in the gas phase, may significantly reduce the inflow performance of sour gas wells and even wells have become completely plugged with sulfur in sour gas reservoir within several months. Accurate prediction and effective management of the sulfur deposition are crucial to the economic viability of sour gas reservoirs.

In this paper, the influences of gas flow rate, initial hydrogen sulfide concentration and reservoir rock permeability on sulfur deposition in the core samples from X sour gas reservoir are investigated from a laboratory and simulation perspective. Displacement experiments were conducted using the gas sample with hydrogen sulfide concentration of 19 %. The gas sample were flooded through the actual carbonate core sample of permeability in the range of 0.85 to 20 millidarcy and under different flow rates of 0.82, 1.25 and 3.50 cc/min. In-situ sulfur deposited was measured using Scanning Electron Microscope (SEM) to provide the amount of sulfur deposited along the core samples. In addition, a three-dimensional, multi-component model was developed to evaluate the influences of gas flow rate, initial hydrogen sulfide concentration and reservoir rock permeability on sulfur deposition.

The results indicated that the higher of gas flow rate can reduce the deposition of sulfur, while the higher of hydrogen sulfide concentration have a severe effect on sulfur deposition in sour gas reservoir. In addition, the depositional rate is accelerated rapidly as the rock permeability decreases. This work can help predict exactly the permeability damage rate as a function of flow rate, or initial rock permeability and production performance during the development of sour gas reservoir.

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