Abstract: According to the acid gas characteristics of low H₂S volume fraction (41%-48%) in Yuanba Natural Gas Purification Plant, sulfur recovery unit adopts the conventional Claus un-conventional divided flow method to recover sulfur. The technology has the advantages of simple process, flexible operation and advanced automatic control. The sulfur recovery process has been applied on the sulfur recovery unit in Yuanba Natural Gas Purification Plant for one year. The results showed while H₂S volume fraction in acid gas is 41%-48%, the Claus furnace temperature is above 1 050 ℃, the conversion rate of sulfur in furnace is 65%-68%, sulfur products reach the national high-class product quality index. The successful application of the technology in sulfur recovery unit of Yuanba Purification Plant will provide references for the similar equipment in natural gas purification plants.