CN216175298U

CN216175298U - Soil normal position thermal desorption system

Info

Publication number: CN216175298U
Application number: CN202122567022.4U
Authority: CN
Inventors: 孟静娟; 赵倩云; 王春宇; 高英超; 李道磊; 司文辉; 陈亭亭; 陈冲
Original assignee: Yuhuan Environment Technology Co ltd
Current assignee: Yuhuan Environment Technology Co ltd
Priority date: 2021-10-25
Filing date: 2021-10-25
Publication date: 2022-04-05
Anticipated expiration: 2031-10-25

Abstract

The utility model relates to a soil in-situ thermal desorption system, which comprises a heating well dug around polluted soil, the heating well is provided with a vent hole, a smoke inlet pipe is arranged in the heating well, the bottom of the smoke inlet pipe is provided with an air vent, a barrier layer is arranged on the upper surface of the polluted soil, a flue gas outlet is arranged on the side wall of the heating well above the barrier layer, the upper end of the heating well is provided with a burner, the side wall of the burner is provided with a flue gas inlet, the flue gas outlet is connected with a condenser, the bottom end of the condenser is connected with an oil-water separator, the bottom end of the oil-water separator is provided with a three-way tapping hole, two ports of the three-way tapping hole are respectively connected with two pipelines, one of them pipeline is water collecting pipe, and a pipeline is oil collecting pipe, the condenser upper end is provided with out the noncondensable gas port, it connects the flue gas import to go out the noncondensable gas port. The utility model can recycle the waste gas discharged by thermal desorption, does not pollute the environment and recycles the waste gas.

Description

Soil normal position thermal desorption system

Technical Field

The utility model relates to the technical field of contaminated soil remediation, in particular to a soil in-situ thermal desorption system.

Background

The thermal desorption technology is a process of heating the soil polluted by organic matters to be above the boiling point of the organic matters, selectively promoting the pollutants to be gasified and volatilized by controlling the temperature of a system and the retention time of materials, separating the pollutants from soil particles and carrying out subsequent treatment. The waste gas treatment unit of the in-situ thermal desorption engineering is mainly used for treating organized process waste gas generated in the links of thermal desorption extraction waste gas, waste water stripping treatment and the like, and most of waste gas treatment devices are complex and complicated and have high energy consumption. At present, after thermal desorption, waste gas is treated and then directly discharged into the atmosphere, so that energy is wasted, and the environment is easily polluted by organic pollutants contained in the waste gas.

The change of the water content of the polluted soil changes the conductivity and the dielectric constant of the soil sample, water has higher dielectric loss factor, and the relative difference of the water content among the soil samples causes the difference of reaction temperature, thereby influencing the removal efficiency of pollutants.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a soil in-situ thermal desorption system which can recycle waste gas discharged by thermal desorption and does not pollute the environment.

The technical scheme of the utility model is as follows:

a soil in-situ thermal desorption system comprises a heating well dug around contaminated soil, wherein air vents are formed in the side wall of the heating well, a smoke inlet pipe is arranged in the heating well, an air vent is formed in the bottom of the smoke inlet pipe, a layer of barrier layer is arranged on the upper surface of the contaminated soil, a smoke outlet is formed in the side wall of the heating well above the barrier layer, a burner is arranged at the upper end of the heating well, a smoke inlet and an air inlet are formed in the side wall of the burner, the smoke outlet is connected with a condenser, a condenser liquid outlet is formed in the bottom end of the condenser, the condenser liquid outlet is connected with an oil-water separator, a three-way liquid discharging port is formed in the bottom end of the oil-water separator, two ports of the three-way liquid discharging port are respectively connected with two pipelines, one pipeline is a water collecting pipeline, the other pipeline is an oil collecting pipeline, and a non-condensing air port is formed in the upper end of the condenser, the non-condensing gas outlet is connected with the flue gas inlet.

Preferably, be provided with the water inlet on the barrier layer, water collecting pipe connects the water inlet, oil collecting pipe connects the collection tank, be provided with the observation window on the tee bend tapping hole.

Preferably, a second induced draft fan is arranged between the noncondensable gas outlet and the flue gas inlet, and a first induced draft fan is arranged on the flue gas outlet.

Preferably, the combustor is a gas combustor, and a liquid caustic soda absorption tank and an activated carbon adsorber are sequentially arranged between the noncondensable gas port and the flue gas inlet.

Preferably, the barrier layer comprises a layer of heat-insulating refractory bricks and a concrete heat-insulating layer laid on the heat-insulating refractory bricks, and the concrete heat-insulating layer is covered with a layer of air-impermeable film.

Preferably, the heating wells are arranged in a regular hexagon.

The utility model has the beneficial effects that:

the utility model can recycle the waste gas discharged by thermal desorption and does not pollute the environment.

And water vapor and organic matter vapor evaporated from the solid phase are introduced into the condenser, are condensed into liquid again after being subjected to water spraying and quenching, the condensed liquid enters the oil-water separator for oil-water separation, filtration and purification, and water flowing out of the water collecting pipeline is reused for cooling and humidifying the soil to be repaired.

The noncondensable gas through the condenser upper end gets into the tobacco pipe once more and burns, guarantees that the pollutant in the noncondensable gas burns once more and decomposes, reduces the not up to standard condition of pollutant in the restoration back waste gas that once burns and insufficiently causes.

The system makes full use of heat conduction energy and reasonably utilizes energy guide. Reduce energy waste and energy consumption cost.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic structural view of a sidewall of a heater well according to the present invention.

Fig. 3 is a schematic structural view of the bottom of the heater well according to the present invention.

In the attached drawing, 1-heating well, 11-smoke inlet pipe, 12-vent, 13-smoke outlet, 14-vent, 21-heat insulation firebrick, 22-concrete heat insulation layer, 23-water inlet, 3-burner, 31-smoke inlet, 32-air inlet, 41-first induced draft fan, 42-second induced draft fan, 5-condenser, 51-condenser liquid outlet, 52-non-condensation gas outlet, 61-three-way liquid outlet, 62-water collecting pipeline, 63-oil collecting pipeline, 7-collecting tank, 8-liquid caustic soda absorbing tank and 9-active carbon absorber.

Detailed Description

As shown in fig. 1-3, a soil in-situ thermal desorption system comprises a heating well 1 dug around contaminated soil, the heating well is arranged in a regular hexagon, a smoke inlet pipe 11 is arranged in the heating well 1, a vent 12 is arranged at the bottom of the smoke inlet pipe 11, a vent 14 is arranged on the side wall of the heating well, a barrier layer is arranged on the upper surface of the contaminated soil, the barrier layer comprises a layer of heat-insulating refractory brick 21 and a concrete heat-insulating layer 22 laid on the heat-insulating refractory brick, a layer of airtight film is covered on the concrete heat-insulating layer 22, a smoke outlet 13 is arranged on the side wall of the heating well 1 above the barrier layer, a burner 3 is arranged at the upper end of the heating well 1, the burner 3 is a gas burner, a smoke inlet 31 and an air inlet 32 are arranged on the side wall of the burner 3, a first induced draft fan 41 is arranged on the

smoke outlet

13, 13 connection condenser 5 of exhanst gas outlet, 5 bottoms of condenser set up condenser liquid outlet 51, and condenser liquid outlet 51 is connected with

oil water separator

6, 6 bottoms of oil water separator are provided with tee bend tapping hole 61, be provided with the observation window on the tee bend tapping hole 61, two pipelines are connected respectively to two mouths of tee bend tapping hole 61, and one of them pipeline is water collection pipeline 62, and a pipeline is oil collection pipeline 63, be provided with water inlet 23 on the barrier layer, water collection pipeline 63 connects water inlet 23. The water vapor and the organic matter vapor evaporated from the solid phase are introduced into the condenser, and are condensed into liquid again after being sprayed and quenched by water, the condensed liquid enters the oil-water separator 6 for oil-water separation, filtration and purification, and the water flowing out of the water collecting pipeline 63 is reused for cooling and humidifying the soil to be repaired. Compared with soil, water has a very high dielectric loss factor value, and water can increase the effective dielectric loss factor value of a soil system, so that the heating capacity of the soil is improved. Therefore, the soil contains a certain amount of water, so that the temperature rise rate of the soil can be effectively improved, and the soil can rapidly enter high temperature. On the other hand, since some contaminants present in the soil have a volatile property, the contaminants are volatilized as the water is evaporated, and thus, the increase in the water content of the soil facilitates the removal of the contaminants from the soil.

The oil collecting pipe 63 is connected with the collecting tank 7, the condenser 5 upper end is provided with out noncondensable gas port 52, it connects the flue gas inlet 31 to go out noncondensable gas port 52, it is provided with the second draught fan 42 to go out between noncondensable gas port 52 and the flue gas inlet 31, liquid caustic soda absorption tank 8 and activated carbon adsorber 9 have set gradually between noncondensable gas port 52 and the flue gas inlet 31. The non-condensable gas is filtered by active carbon and then enters a combustion chamber for combustion, and heat is recovered while gaseous pollutants are decomposed.

The gas enters the gas burner 3 above the heating well 1 through the smoke inlet 31, then the gas is combusted in the smoke inlet pipe 11, then enters the heating well 1 from the air vent 12 under the action of a first induced draft fan 41, when the temperature is 450-650 ℃, organic pollutants in soil around the heating well are heated to a boiling point, are evaporated and desorbed from the soil around the heating well, enter the heating well 1 from the air vent 14, are discharged from the smoke outlet 13 and enter the condenser 5 for condensation treatment;

the water vapor and organic matter vapor evaporated from the soil around the heating well 1 are introduced into the condenser 5, on one hand, the incomplete combustion of the waste gas is avoided, on the other hand, the generated harmful gas is prevented from directly entering the atmosphere and being condensed into liquid by the condenser 5, the condensed liquid enters the oil-water separator 6 from the liquid outlet of the condenser 5 for oil-water separation, the water in the water collecting pipeline 62 is reused for cooling and humidifying the treated dry soil through the water inlet 23 on the barrier layer, the redundant carbon dioxide in the non-condensed gas from the non-condensed gas port 52 at the upper end of the condenser 5 is absorbed by the alkali liquor in the alkali liquor absorption device 8, the impurities and the redundant water are filtered by the active carbon filter 9 and then enter the smoke inlet 31 again for combustion in the smoke inlet pipe 11, the oil produced in the oil-water separation process can be discharged into the collecting tank 7 for recycling through the oil collecting pipeline 63, and observing the water-oil separation interface according to the observation window.

The noncondensable gas passing through the upper end of the condenser 5 enters the smoke pipe 11 again for burning, so that pollutants in the noncondensable gas are guaranteed to be burned and decomposed again, and the condition that the pollutants in the repaired waste gas do not reach the standard due to insufficient primary burning is reduced.

In other embodiments, the heat conducting pipeline for cooling the hot gas in the condenser 5 has a higher temperature after guiding the flue gas heated at a high temperature, the heat conducting pipeline can be wound around the output pipeline of the noncondensable gas port 52 and the output pipeline of the water collecting pipeline 62, the heat in the heat conducting pipeline is heated on the noncondensable gas and the inlet water in the inlet water pipe 23, and the heat conducting pipeline is cooled by the fluid in the heat conducting pipeline after heat transfer and can be circulated to the inside of the condenser 5 again. The system makes full use of heat conduction energy and reasonably utilizes energy guide. Reduce energy waste and energy consumption cost.

The embodiments described above are only preferred embodiments of the utility model and are not exhaustive of the possible implementations of the utility model. Any obvious modifications to the above would be obvious to those of ordinary skill in the art, but would not bring the utility model so modified beyond the spirit and scope of the present invention.

Claims

1. A soil in-situ thermal desorption system is characterized by comprising a heating well dug around contaminated soil, wherein the side wall of the heating well is provided with air vents, a smoke inlet pipe is arranged in the heating well, the bottom of the smoke inlet pipe is provided with an air vent, the upper surface of the contaminated soil is provided with a layer of barrier layer, the side wall of the heating well above the barrier layer is provided with a smoke outlet, the upper end of the heating well is provided with a burner, the side wall of the burner is provided with a smoke inlet and an air inlet, the smoke outlet is connected with a condenser, the bottom end of the condenser is provided with a condenser liquid outlet, the condenser liquid outlet is connected with an oil-water separator, the bottom end of the oil-water separator is provided with a three-way liquid discharge port, two ports of the three-way liquid discharge port are respectively connected with two pipelines, one pipeline is a water collecting pipeline, one pipeline is an oil collecting pipeline, and the upper end of the condenser is provided with a non-condensing gas vent, the non-condensing gas outlet is connected with the flue gas inlet.

2. The in-situ soil thermal desorption system of claim 1, wherein the barrier layer is provided with a water inlet, the water collection pipe is connected with the water inlet, the oil collection pipe is connected with the collection tank, and the tee-joint liquid outlet is provided with an observation window.

3. The in-situ soil thermal desorption system of claim 1, wherein a second induced draft fan is arranged between the noncondensable gas outlet and the flue gas inlet, and a first induced draft fan is arranged on the flue gas outlet.

4. The in-situ soil thermal desorption system of claim 1, wherein the burner is a gas burner, and a liquid caustic soda absorption tank and an activated carbon adsorber are sequentially arranged between the non-condensation gas port and the flue gas inlet.

5. The in-situ soil thermal desorption system of claim 1, wherein the barrier layer comprises a layer of heat-insulating refractory bricks and a layer of concrete heat-insulating layer laid on the heat-insulating refractory bricks, and the layer of concrete heat-insulating layer is covered with a gas-impermeable film.

6. The in-situ soil thermal desorption system of claim 1 wherein the heater wells are in a regular hexagonal arrangement.