The Puguang Natural Gas Plant has been in operation since 2010. It produced more than eight percent of China’s total natural gas output in its first year of operation. It has also become a major supply of domestic elemental sulfur in China.
The Puguang gas field is one of the largest of its kind in Asia. Discovered in 2003, the field’s raw natural gas is sour, which means it must be purified before it can be used for commercial purposes. The sour gas at Puguang contains large volumes of hydrogen sulphide, in addition to having appreciable carbon dioxide content.
Black & Veatch helped the client overcome this challenge through its proven Interstage Cooling technology. This enhanced selective treating configuration is one of the key features of the design that enables the facility to significantly reduce the volume of inerts processed in the SRU as well as reduce capital and operating costs compared to other technologies.
As part of a complete sour gas purification and sulfur recovery scheme, Black & Veatch provided process design engineering, technology licensing and field support services. The Puguang Natural Gas Plant can process up to 36 million normal cubic meters of raw natural gas per day. It removes virtually all hydrogen sulfide, which makes up nearly 15 percent of the raw gas volume, and converts it to elemental sulfur. It also reduces carbon dioxide content from 10 percent to three percent of total volume to meet sales gas specifications.
The processing plant also serves as one of the largest sulfur production facilities in the world, producing up to 8,400 metric tons per day and 3 million tons annually. China is currently the world’s largest consumer and importer of elemental sulfur, which is primarily used as feedstock to produce sulfuric acid and ultimately, phosphate fertilizers. In 2009, it consumed approximately 11 million tons, with approximately 80 percent coming from imports.
The Puguang Field, with its 3 million tons of annual sulfur production capacity, is capable of meeting more than 25 percent of China’s elemental sulfur demand.