Pieridae is also buying three sour gas plants.

Chevron is an experienced sour gas developer, and has partnered with PetroChina to develop gas in Australia.

Gas pumped from the Sichuan basin, both conventional and unconventional, is mostly sour gas that contains H2S.

The plant mentioned in the new letter processes sour gas so it can be sold to the public.

It has trebled output since 1999, overcoming technical challenges such as high reservoir pressures and very sour gas.

Chevron, an experienced sour gas developer, is the operator of the project, and holds a 49 percent stake.

Chuandongbei is a sour gas development.

The full development will include two sour gas processing plants and five natural gas fields with gathering systems and tie-ins to the plants.

Bab, and the almost as technically challenging Shah sour gas project, are vital to limit the UAE's growing gas imports over the next decade.