In recent years, with the implementation of the compulsory classification policy of domestic waste and the promotion of the four-division classification method, kitchen waste will be treated separately and resourced, and the dry anaerobic comprehensive treatment of kitchen waste will gradually become the mainstream technology. At present, the development and application of dry anaerobic technology in foreign countries have been very mature, but the application of dry anaerobic technology independently developed in China in large-scale industrial projects is still rare.

In recent years, with the implementation of the compulsory classification policy of domestic waste and the promotion of the four-division classification method, kitchen waste will be treated separately and resourced, and the dry anaerobic comprehensive treatment of kitchen waste will gradually become the mainstream technology. At present, the development and application of dry anaerobic technology in foreign countries have been very mature, but the application of dry anaerobic technology independently developed in China in large-scale industrial projects is still rare.

The dry anaerobic fermentation process needs to solve the contradiction between high solid content and mass transfer, maintain the homogeneity of the material in the tank, and avoid phase separation. Therefore, the requirements for the tank structure and stirring method are very high, which is also the technical difficulty of the dry anaerobic fermentation process.

In addition to the control of the biochemical system, another key issue is to ensure high efficiency mixing operation, which is also one of the important means to avoid phase separation of materials in the tank. Generally, the dry anaerobic fermentation process requires strict control of the solid content, viscosity, inert material ratio, etc. in the tank. For dry anaerobic fermentation system, no matter vertical or horizontal structure, once phase separation occurs, three-phase separation of heavy, water and light materials will occur in the tank, and heavy materials will be separated. After this happens, for the horizontal mechanical stirring mode, the deposits in the tank will cause the mechanical stirring to fail. It is almost impossible to restore the system to the operating state without the tank. In the vertical tank, if the bottom cone bottom discharge is used, once the phase separation occurs, the sediment will block the discharge port, and the tank needs to be cleaned and restarted. If the bottom high-pressure biogas is used for stirring, deposition will reduce the stirring efficiency, but will not affect the operation of high-pressure biogas stirring. At the same time, the vertical tank outlet is provided with low and high outlets. The high level outlet can be used for continuous draining and backflow when sediment blocks the low level outlet. In addition, the normal operation of high-pressure gas stirring can restore the operation of the tank body in the unclear tank state.

The main structure types of dry anaerobic fermentation equipment are mainly divided into horizontal fermentation tank and vertical fermentation tank, in which the horizontal fermentation tank with internal structure is mainly divided into single-axis and multi-axis, and the vertical fermentation tank is divided into gas stirring and material self-circulating stirring.

Horizontal single shaft dry fermentation dry anaerobic equipment is a horizontal container made of reinforced concrete and steel structure. The advantages of this equipment are: the horizontal thrust flow from the front end of the container to the back end forms a relatively stable feeding and discharging process; Disadvantages:"Half bottom" shape, complex structure, high cost. This equipment has only one agitator, which is limited by the length of the agitator shaft and the upper limit of the shaft torque. The design length of the container and the length of the main shaft are limited, as is the maximum volume of the container.

Horizontal multi-shaft dry fermentation dry anaerobic equipment is a horizontal container made of reinforced concrete or precast concrete. The advantage is that the cross section of the container adopts standardized design, and each mixing unit adopts modular design and manufacturing, so the length of the container can be changed according to the needs of the project scale, so that the volume of the equipment meets the design requirements, and the material flow form is from the front end of the container to the back The flat thrust flow forms a relatively stable feeding and discharging process. The container adopts simple rectangular concrete formwork, which can greatly reduce the design cycle, design cost and construction difficulty.