To identify a scientific and rational process route for meeting tail gas emission standards all the time in sulfur-containing natural gas purification plants, this paper examines the status quo of tail gas treatment technologies and the technical attributes of various sulfur-containing tail gas treatment processes. According to the different sulfur recovery and tail gas treatment processes adopted by existing plants, several potential process routes that comply with the emission standard are proposed. The pros and cons on technical and economic aspects of each process route were compared and analyzed, Finally, this paper concludes by advocating for a tailored approach—“one plant, one policy” “site-specific strategies” and “integrating short-term and long-term emission reduction”—in developing optimum process routes. This is intended to offer technical support for the standardization and upgrading of tail gas treatment units in future sulfur gas purification plants.