Coal production mainly includes screening, coal preparation, coal forming, coal pulping, coal combustion, coal conversion and so on.
Screening: Use screening equipment to divide the mined raw coal into different sizes, and remove the visible gangue and debris in the specified size.
Coal preparation: The process of processing the screened coal by physical or physical-chemical methods, and sorting out products of different quality or particle size. According to whether the separation medium is water, air or oil, coal preparation is divided into wet coal preparation, dry coal preparation and oil group coal preparation. Wet coal preparation is the most widely used, and it includes many operations, such as raw coal storage, coal blending, crushing, jigging, dense medium separation, flotation, special separation, coal slime water treatment, dehydration, dust removal, drying, storage, etc. Yun, etc., their mutual cooperation constitutes a variety of different coal preparation processes. According to the characteristics of raw coal, user requirements for products, geographical environment and other conditions, different coal preparation processes are selected to meet the requirements of metallurgy, steel, electric power , railway, fertilizer and various civil applications. Coal preparation is the basis of coal processing, which fundamentally improves the quality of coal products, improves thermal efficiency and reduces environmental pollution .
Coal forming: Processing pulverized coal into a job with a certain shape, size and specific properties at higher pressure, appropriate temperature or blending a certain amount of binder. After the coal is formed, due to the normalization of the external dimensions, the reduction of moisture and the change of the combustion method, it is conducive to the improvement of clean combustion and thermal efficiency. In particular, the lignite with high internal moisture and low calorific value can significantly improve the quality after processing and molding, which is convenient for storage and transportation, expands the use and improves the use value.
The molding method is divided into binderless molding and binder molding. The forming process includes cold pressing, hot pressing and pellet forming. The shapes of briquette are oval, pillow, cylindrical and square column.
The briquette is divided into two types: industrial briquette and civil briquette. The former includes fuel briquette and raw material briquette, while the latter is mainly honeycomb briquettes and briquettes.