A dual-position spiral drying and roasting kiln with external heating for soil ectopic restoration

Abstract

The invention discloses a dual-position spiral drying and roasting kiln with external heating for soil ectopic restoration. It includes upper and lower furnace bodies; two furnace tubes are installed in each of the upper and lower furnace bodies; the feeding bin is connected to the feed port of the upper furnace tube through a rotary vane feeder; the rotary vane feeder is connected to a drive motor with a frequency converter; The upper furnace tube and the lower furnace tube are equipped with screw conveying augers, which are connected to the transmission reducer with frequency converter; the working frequency of the rotary vane feeder is consistent with that of the screw conveying auger, ensuring The material speed is consistent; the right side of the upper furnace tube is connected up and down with the right side of the lower furnace tube; the discharge port at the bottom of the lower furnace tube is equipped with a discharge conveyor; the top of the upper furnace tube is equipped with a water spray humidifier; the bottom of the furnace body is equipped with a burner. The equipment has small volume, low site requirements, high thermal desorption efficiency, low equipment failure rate, and low energy consumption; Eliminate the gap between the furnace tube and the furnace to reduce heat dissipation.

Description

technical field [0001] The invention belongs to the technical field of soil restoration equipment, and relates to a drying and roasting kiln, in particular to an external heating double-position spiral drying and roasting kiln for heterotopic soil restoration. Background technique [0002] Thermal desorption technology is an important means of contaminated soil remediation technology. Thermal desorption technology is a process in which the target organic pollutants are volatilized or separated from the soil by heating the contaminated soil above the boiling point of the target pollutants. During the desorption process, the target pollutants undergo evaporation, distillation, boiling, oxidation and pyrolysis. By controlling the system temperature and material residence time, different pollutants can be selectively removed. The pollutants in the polluted soil are under negative pressure conditions It is separated from the soil and finally enters the gas treatment system for co...

AI Technical Summary

Problems solved by technology

However, during the operation of the rotary furnace or other thermal desorption equipment, the failure rate of the equipment is high, the energy consumption is large, the use is inconvenient, the thermal desorption efficiency is low, the running time is long, the operation and maintenance are relatively complicated, and the equipment The investment cost is also relatively large, and there may be secondary pollution during the operation process. Moreover, the existing equipment is large in size, has high requirements for the site, and requires pre-screening and crushing of the soil, which increases the cost of thermal desorption.

[0005] In addition, the current general-purpose thermal desorption furnace tube has the following defects: the existing general-purpose thermal desorption furnace tube has only one side ( The right side) is fixed by the bearing, and the auger and the material it conveys have gravity, which causes the helical blade on the other side (left side) of the auger axis to directly contact the inner wall of the furnace tube, causing the auger to contact the furnace tube during rotation. The side of the inner wall of the tube in contact with the continuous friction makes the tube wall of the furnace tube thinner; moreover, the temperature inside the furnace usually reaches above 550°C. That is to say, the furnace tube needs to be replaced in about one year; and the replacement of the furnace tube is relatively difficult, and the replacement of the furnace tube takes a long time, the cost is high, and the shutdown of the construction site will also cause great losses

At the same time, the existing general-purpose furnace tube design will also lead to a large gap between the furnace tube and the furnace (furnace body), resulting in heat dissipation and high energy consumption, which is not conducive to energy saving and consumption reduction.

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