Drying Technology
Keywords: Municipal Sludge、Waste water treatment
It is recommended to choose indirect drying form for drying equipment, which should be energy-saving and have low odor production; After drying, plunger pumps can be used for sludge transportation. When designing the transportation pipeline and plunger pump, various working conditions should be fully considered, and existing project operating experience should be combined to optimize the design reasonably, saving investment and transportation costs
Direct drying
Direct drying is the process of sending high-temperature flue gas into a drying machine, where it comes into direct contact with sludge to form an air flow for heat exchange, resulting in high thermal energy utilization efficiency. However, the continuous entry of high-temperature flue gas will bring about an equal amount of exhaust gas that comes into direct contact with the material as the incoming flue gas. Therefore, the exhaust gas must be specially treated before it can be discharged. Direct drying representative equipment includes drum, belt, fluidized bed and other drying machines. This project uses steam as the heat source, and the direct drying method is not suitable for this project.
Indirect drying
Indirect drying is the process of utilizing the thermal energy of high-temperature flue gas through a heat exchanger to transfer it to air, thermal oil, or steam. Air, thermal oil or steam circulate in a closed system without direct contact with the sludge that needs to be dried. The representative equipment for indirect drying includes rotary disc (blade) type, belt type, thin layer and other drying machines, so the indirect drying method is suitable for this project.
The sludge receiving system, wet sludge conveying system, sludge drying system, dried sludge conveying system, and deodorization system are all operating normally. The system design has high stability and suitable equipment capacity margin, which can meet the operational needs under abnormal working conditions. The dried sludge conveying system can operate stably without the need for pipeline membrane injection and electric tracing emergency measures.
