Method and equipment for treating organic polluted soil by two-stage indirect thermal desorption process

Abstract

The invention discloses a method and equipment for treating organic polluted soil by a two-stage indirect thermal analysis process. The steps are: carry out low-temperature pre-drying and dehydration in the pre-drying device for the moisture in the organic polluted soil, so that the moisture content is reduced to <5%; Heating to obtain high-temperature soil and organic pollutant gas; the organic pollutant gas is directly introduced into the combustion heating device and burned at high temperature together with the fuel to realize the complete and harmless treatment of organic pollutants; the high-temperature soil is indirectly cooled by the hot soil cooling device, and recycled The sensible heat of high-temperature soil is used to preheat the air, which is used to burn the fuel of the heating device, and the obtained product can be further processed and used as a raw material for building materials. The process is simple, the investment is small, the operation and management costs are low, the energy efficiency is high, and there is no tail gas pollution or any other environmental protection problems. While the technology and economy are feasible, the energy saving and environmental protection benefits are remarkable, which fully embodies the concept of clean production and circular economy.

Description

technical field [0001] The invention relates to the field of harmless treatment of polluted soil. In particular, it relates to a method and equipment for treating organic polluted soil by a two-stage indirect thermal desorption process. Background technique [0002] In recent years, with the rapid development of my country's economy, a large number of chemical enterprises have been closed, relocated or about to be decommissioned. These enterprises have caused serious damage due to factors such as product production and treatment, waste dumping and discharge, and chemical substance leakage. The problem of site pollution. As most of the chemical companies are concentrated in cities, most of the polluted sites are currently facing the conversion of land use functions and secondary development. The polluted soil in these sites seriously threatens human health and environmental safety, and indirectly affects the secondary use of land. This has become an urgent need Solve soil en...

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Problems solved by technology

The above-mentioned method is complex in system process, highly dependent on the cement plant, and difficult to implement

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