Overview of Printing and Dyeing Sludge Dryer Engineering

　　Printing and dyeing wastewater has high concentration and chromaticity of organic matter, complex components, and is usually treated by physical, chemical, and biological methods. Printing and dyeing sludge is a byproduct of printing and dyeing wastewater treatment, which is an extremely complex heterogeneous body composed of organic residues, bacterial bodies, inorganic particles, colloids, etc. If discharged directly without treatment, it can cause significant environmental pollution. And sludge drying treatment can completely, quickly, and maximally reduce capacity and volume, and is expected to become the mainstream technology for printing and dyeing sludge treatment and disposal in the future.

　　In response to the relevant characteristics of printing and dyeing sludge, our company has developed the KJG series hollow blade dryer and efficient tail gas treatment device. After practical application by many customers, sufficient usage data has proven that this equipment can fully meet the drying requirements of printing and dyeing sludge, with stable operation, uniform mixing, high thermal efficiency, good drying effect, low energy consumption, and low operating costs.

　　This system includes a heating system, an inlet and outlet system, a drying system, and a tail gas treatment system.

Working principle of printing and dyeing sludge dryer

　　The heat transfer surface of the hollow blade dryer consists of several parts such as blades, mixing shaft, and wall surface, and the heat transfer area of the blades accounts for a large part. Therefore, the equipment has a compact structure and a large heat transfer area per unit volume. In addition, stirring and mixing make the sludge turn violently, thus obtaining a very high heat transfer coefficient, so the floor area and space are very small, saving the plant infrastructure costs. During the drying process, the gas consumption is low, the flow rate is low, and the amount of dust carried away by the gas is small. Therefore, the recovery of gas and dust after drying is convenient, and the volume of the recovery equipment is small, which can save equipment investment.

　　The core of the paddle dryer is two hollow shafts and hollow stirring blades welded to the shafts. The blade shape is a wedge-shaped hollow semicircle that can be fed into the heating medium. In addition to serving as a stirring agent, it is also a heat transfer agent for the equipment. The two main heat transfer sides of the blade form an inclined plane, so when the material comes into contact with the inclined plane, as the blade rotates, the particles quickly slide away from the inclined plane, constantly updating the heat transfer surface and strengthening heat transfer. There is a scraper at the bottom of the triangle of the blade to scrape up the material deposited at the bottom of the shell and prevent dead corners.