The petrochemical industry is an important basic and pillar industry of the country, covering the exploration, development, production and investment, operation and trade of oil and natural gas and its related products. According to Shenwan's industry classification standards, the industry can be subdivided into three categories: oil and gas exploitation, oil service engineering, refining and trade. The petrochemical industry has a huge total economic volume and a high degree of industrial relevance in the national economy, and is a key industry to support economic development.