Low-temperature laminated sludge dehydrating and drying box

Abstract

The invention discloses a low-temperature laminated sludge dehydrating and drying box, which utilizes a laminated ventilation principle (by utilizing wind energy) and combines with a low-temperature circulating system to perform drying treatment. The technical scheme of the invention is the process of evaporating water in sludge by an external heat source which is lower than the burning point of the sludge. The urban sludge has a relatively high calorific value due to the containing of a large quantity of organic substances, which lays a foundation for enabling the sludge to have the potential value in resource utilization and also decides the possibility in harmless and resource treatment of the urban sludge. The basic condition for enabling the urban sludge to contribute to the calorific value is that the water content in the sludge needs to be reduced from about 80% when the sludge is discharged from a sewage treatment plant to below 30%, i.e., whether the resource utilization of the urban sludge can be realized or not depends on the key technology of deep dehydration of the sludge. The energy consumption bottleneck of sludge drying can be thoroughly overcome, and the operation cost for sludge treatment is greatly reduced. The low-temperature laminated sludge dehydrating and drying box can fully reflect the national reduction, harmlessness, stabilization and resource utilization disposal requirements against wastes including the sludge.

Description

technical field [0001] The invention relates to a low-temperature stacked sludge dehydration and drying equipment for sludge. It belongs to the process technology of sludge dehydration and disposal in the process of sewage treatment. Background technique [0002] Sludge is the concentration of pollutants in the sewage treatment process. Sludge has a high moisture content, is easy to be corrupted, has a bad smell, and contains heavy metals and organic pollutants. Random stacking or simple treatment will have a high risk of secondary pollution, destroying soil, air and water resources. After some heavy metals in the sludge seep into the groundwater, they may pass through the food chain such as fish and shrimp and return to the dining table. However, sludge The pollution to the environment by the harmful ingredients in the food often takes a long time to show up. It is this concealment that makes government departments and the public ignore the dangers of sludge and the urge...

AI Technical Summary

Problems solved by technology

However, sludge drying is a process of net energy consumption, and energy consumption usually accounts for more than 80% of the total cost of sludge treatment. Beijing Qinghe Sludge Drying Plant needs 70 cubic meters of natural gas to dry one ton of sludge, and the operating cost is about 300-400 yuan / ton, and most sewage treatment plants are basically unable to afford this huge cost

However, the current sewage treatment fee system in China does not consider the cost of sludge treatment and disposal. Even if there is, it only includes the cost of sludge dehydration (that is, dehydration of wet sludge into sludge with a moisture content of 80%) and the cost of cleaning and transportation.

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