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It is an important part of the chemical industry, plays an important role in the development of the national economy, and is one of the pillar industrial sectors in our country. Petrochemical refers to the processing industry that uses oil and natural gas as raw materials to produce petroleum products and petrochemical products. Petroleum products, also known as oil products, mainly include a variety of fuel oils (gasoline, kerosene, diesel, etc.) and lubricants, as well as liquefied petroleum gas, petroleum coke.

Mine refers to an independent production and management unit with a certain mining boundary. The mine mainly includes one or more mining workshops (or pits, mines, open-pit stopes, etc.) and some auxiliary workshops, and most mines also include beneficiation plants (coal washing plants). The size of the mine scale should be commensurate with the economic and reasonable service life of the mine, only in this way can capital construction costs be saved.