Two-stage deep heat pump sludge drying system

Abstract

The invention relates to a two-stage deep heat pump sludge drying system. According to the system, a drying section arranged between a strip cutting forming machine and a dry material bin is dried through an arranged heat pump structure, wherein the heat pump structure comprises a compressor set, a condenser set and an evaporator set, the drying section comprises a first-stage drying section for normal drying and a second-stage drying section for deep drying, the condenser set comprises a first condenser set and a second condenser set, the first condenser set and the second condenser set are sequentially connected in series behind the compressor set, the first condenser set is used for providing hot air for drying the second-stage drying section, and the second condenser set is used for providing hot air for drying the first-stage drying section; a first circulating wind channel is arranged for the first-stage drying section, a second circulating wind channel is arranged for the second-stage drying section, and the second condenser set is matched with the first circulating wind channel to normally dry the sludge at the section is formed; the first condenser set is matched with thesecond circulating wind channel to deeply dry the sludge at the section; and the temperature of the sludge subjected to second-stage drying can reach more than 80 DEG C while the water content reachesless than 10%, so that the high-temperature sterilization of the sludge is completed.

Description

technical field [0001] The invention belongs to the field of sludge treatment. Specifically, it relates to a two-stage deep heat pump sludge drying system. Background technique [0002] As my country pays more and more attention to the environmental protection industry, sludge treatment has been paid more and more attention by people. At present, domestic sludge dewatering equipment is mainly based on belt filter presses, and the performance of domestic belt filter presses has gradually approached that of world products. However, through mechanical dehydration, it is difficult to achieve a moisture content lower than 60%, which requires thermal forced drying. The common characteristics of thermal forced drying are complex systems, deodorization treatment, high drying temperature, and high energy consumption. The thawed sludge needs to be cooled before it can be stored and transported. Due to the above characteristics, the application of thermal forced drying is difficult ...

AI Technical Summary

Problems solved by technology

However, through mechanical dehydration, it is difficult to achieve a moisture content lower than 60%, which requires thermal forced drying. The common characteristics of thermal forced drying are complex systems, deodorization treatment, high drying temperature, and high energy consumption. The sludge needs to be cooled before it can be stored and transported

Due to the above characteristics, the application of thermal forced drying is difficult to be widely used. In order to solve the above problems, a heat pump type closed sludge drying system has appeared on the market, but because this system is dehumidification and drying, The return air temperature can only reach a maximum of 65 degrees. No matter how high the return temperature is, it will exceed the working range of the compressor and easily damage the compressor. At the same time, the drying temperature sent to the bottom of the sludge is only about 75 degrees. When the drying moisture content reaches about 10%, the drying will be very difficult, the drying time is long, the drying cost is high, and there is still a lot of heat that needs to be discharged by cooling towers or air-cooled condensers

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