Under the contract, Praxair will supply industrial gases for CNOOC’s refinery and downstream chemical production, starting in 2017.

Praxair will build, own and operate two 2,400t a day air separation plants in the Huizhou Daya Bay Chemical Industrial Park, located in Guangdong, to supply oxygen and nitrogen for CNOOC’s refinery.

CNOOC is expanding its refinery capacity from 250,000 to 460,000 barrels of oil per day.

Praxair Asia president John Panikar said: "This new agreement is a result of the strong relationship we have built with China National Offshore Oil Company over time, as we have provided them with the reliable supply of industrial gases they need to successfully run their operations.

"The project also expands Praxair’s operations in southern China, particularly in the coastal region, where we have already built a significant presence."

Currently, Praxair serves other customers in the Park including the existing CNOOC refinery and the CNOOC and Shell petrochemical complex.

Praxair produces atmospheric, process and specialty gases, and high-performance surface coatings.