Method and device for treating organic polluted soil by two-section-type indirect thermal desorption technology

Abstract

The invention discloses a method and a device for treating organic polluted soil by a two-section-type indirect thermal desorption technology. The method comprises the following steps: carrying out predrying and dehydrating moisture in organic polluted soil at low temperature so as to enable the moisture content to be reduced to be less than 5%; heating the predried organic polluted soil in a thermal desorption device indirectly so as to obtain altithermal soil and organic pollutant gas; directly introducing the organic pollutant gas into a combustion heating device to be combusted together with fuels at high temperature so as to achieve the complete innocent treatment of organic pollutants; cooling the high-temperature soil indirectly by a hot soil cooling device, recycling the altithermal soil to sense heat so as to preheat air for the fuel combustion for the combustion heating device, thereby obtaining raw materials for building materials for further deep processing. The technology is simple; the investment is low; the running management expense is low; the energy source efficiency is high; tail gas pollution and any other environment problem are not generated; the technical economy is feasible, and the energy conservation and environment-friendly benefit is obvious; the concept of clean production and circulation economy is shown fully.

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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CN1586747 discloses an off-site treatment process and device for soil polluted by volatile and semi-volatile organic compounds. A vacuum pump is used to form a certain degree of vacuum, and fresh air is continuously introduced into the polluted soil to promote the volatilization of the pollutants adsorbed by the soil. Take away its steam; this method is small in scale, high in cost, and does not effectively treat organic pollutants

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