Chemical industry is the abbreviation of "chemical process", "chemical industry", "chemical engineering", etc. Any technology that uses chemical methods to change the composition and structure of substances or synthesize new substances belongs to chemical production technology, that is, chemical process. The products obtained are called chemicals or chemical products. At first, it was a manual workshop that produced such products. Later, it evolved into a factory, and gradually formed a specific production industry, that is, the chemical industry. Chemical engineering is a science to study the common laws of chemical product production process. The relationship between human beings and chemical industry is very close. Some chemical products have played an epoch-making role in the history of human development. Their production and application even represent a certain historical stage of human civilization.