CN113172084A - Soil remediation system and method for enhancing thermal desorption effect - Google Patents
Soil remediation system and method for enhancing thermal desorption effect Download PDFInfo
- Publication number
- CN113172084A CN113172084A CN202110503938.5A CN202110503938A CN113172084A CN 113172084 A CN113172084 A CN 113172084A CN 202110503938 A CN202110503938 A CN 202110503938A CN 113172084 A CN113172084 A CN 113172084A
- Authority
- CN
- China
- Prior art keywords
- well
- soil
- gas injection
- extraction well
- gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000002689 soil Substances 0.000 title claims abstract description 115
- 238000003795 desorption Methods 0.000 title claims abstract description 29
- 238000005067 remediation Methods 0.000 title claims abstract description 27
- 230000000694 effects Effects 0.000 title claims abstract description 20
- 230000002708 enhancing effect Effects 0.000 title claims abstract description 18
- 238000000034 method Methods 0.000 title claims abstract description 17
- 238000000605 extraction Methods 0.000 claims abstract description 124
- 239000007789 gas Substances 0.000 claims abstract description 109
- 238000002347 injection Methods 0.000 claims abstract description 80
- 239000007924 injection Substances 0.000 claims abstract description 80
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 47
- 239000003546 flue gas Substances 0.000 claims abstract description 46
- 239000003344 environmental pollutant Substances 0.000 claims abstract description 44
- 231100000719 pollutant Toxicity 0.000 claims abstract description 44
- 238000010438 heat treatment Methods 0.000 claims abstract description 42
- 239000000779 smoke Substances 0.000 claims abstract description 22
- 239000002344 surface layer Substances 0.000 claims abstract description 4
- 239000006004 Quartz sand Substances 0.000 claims description 25
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 25
- 239000010410 layer Substances 0.000 claims description 23
- 238000002485 combustion reaction Methods 0.000 claims description 12
- 230000004888 barrier function Effects 0.000 claims description 7
- 230000009471 action Effects 0.000 claims description 6
- 229910001220 stainless steel Inorganic materials 0.000 claims description 3
- 238000002156 mixing Methods 0.000 claims description 2
- 238000005276 aerator Methods 0.000 claims 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 20
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 abstract description 6
- 229910002092 carbon dioxide Inorganic materials 0.000 abstract description 3
- 239000001569 carbon dioxide Substances 0.000 abstract description 3
- 239000002918 waste heat Substances 0.000 abstract description 3
- 238000005728 strengthening Methods 0.000 abstract description 2
- 230000035699 permeability Effects 0.000 description 16
- 239000012071 phase Substances 0.000 description 10
- 238000005273 aeration Methods 0.000 description 9
- 238000005516 engineering process Methods 0.000 description 7
- 238000001816 cooling Methods 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 239000011362 coarse particle Substances 0.000 description 5
- 239000007788 liquid Substances 0.000 description 5
- 239000002737 fuel gas Substances 0.000 description 4
- 239000003673 groundwater Substances 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 239000000356 contaminant Substances 0.000 description 3
- 239000010865 sewage Substances 0.000 description 3
- 239000003802 soil pollutant Substances 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- XLYOFNOQVPJJNP-ZSJDYOACSA-N Heavy water Chemical compound [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000008439 repair process Effects 0.000 description 2
- 239000002912 waste gas Substances 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 239000008346 aqueous phase Substances 0.000 description 1
- 238000009395 breeding Methods 0.000 description 1
- 230000001488 breeding effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011066 ex-situ storage Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000005693 optoelectronics Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000013618 particulate matter Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000002680 soil gas Substances 0.000 description 1
- 230000004083 survival effect Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B09—DISPOSAL OF SOLID WASTE; RECLAMATION OF CONTAMINATED SOIL
- B09C—RECLAMATION OF CONTAMINATED SOIL
- B09C1/00—Reclamation of contaminated soil
- B09C1/06—Reclamation of contaminated soil thermally
Landscapes
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Soil Sciences (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Processing Of Solid Wastes (AREA)
Abstract
The invention provides a soil remediation system and method for strengthening thermal desorption effect, which comprises a heating well, an extraction well and a gas injection well which are buried below the surface layer of soil to be remediated, a heat supply device for providing heat for the heating well, a vacuum pump for extracting gas in the extraction well and a pollutant treatment device for treating the gas extracted by the vacuum pump; the heating well is an inner sleeve type heating well and an outer sleeve type heating well, and smoke generated by the heat supply device enters from an inlet at the upper part of the inner sleeve and enters the outer sleeve from an outlet at the bottom of the inner sleeve; the upper part of the outer sleeve is provided with a flue gas outlet communicated with a gas injection well. On one hand, the invention can fully utilize the waste heat of the flue gas and the soil to enhance mass and heat transfer and accelerate the temperature rise of the soil; on the other hand, the flue gas contains a large amount of water vapor and carbon dioxide to enhance the flow of pollutants in the soil, thereby enhancing the extraction efficiency.
Description
Technical Field
The invention relates to the field of soil remediation, is mainly applied to an organic contaminated soil treatment field, and particularly relates to a soil remediation system and method for enhancing a gas thermal desorption effect.
Background
Soil plays a vital role in human daily life as part of human survival. However, with rapid development of economy and improvement of industrial technology level, pollution of domestic daily life, planting and breeding and industrial and mining enterprises to soil is mutually superposed, and the current situation that a plurality of new and old pollution sources and secondary pollution are mutually mixed is formed. The current situation poses serious threats to the quality safety, the ecological environment safety, the human health and even the sustainable development of social economy in China.
The soil remediation methods adopted in China at present can be roughly divided into three types: the three restoration modes of chemical restoration, biological restoration and physical restoration have advantages and disadvantages, but in the aspects of restoration period and pollutant removal effect, the main restoration mode still adopts physical restoration at present, and the gas thermal desorption is taken as one of the main methods in the physical restoration, so that the method has more obvious effect in treating the high-concentration organic polluted soil. Before using the thermal desorption of the fuel gas, the total amount of soil pollutants can be divided into:
Qz＝Qs+Qg+Ql+NAPLs
wherein Qz-total amount of contaminants; qs-the amount of contaminants adsorbed to the soil; qg-amount of pollutants volatilized from the soil gas; ql-amount of contaminants dissolved in groundwater; NAPLs-non-aqueous phase fluids.
The principle of the gas thermal desorption technology is that the high-temperature flue gas after combustion heats the soil, so that the pollutant Q adsorbed on the soilsDesorbed from the soil, and the NAPLs can be accelerated to migrate to the gas phase pollutants by heating, and the other two-phase pollutants are pumped into the tail end treatment through the extraction pipe. The gas thermal desorption technology is very perfect in principle, but still has great defects, firstly, the heat of combustion flue gas cannot be fully utilized, and about 20 percent of residual heat can be seriously wasted according to the calculation of the current engineering example. Secondly, the pollutant desorption effect of the early stage of the gas thermal desorption technology is excellent, but when the concentration of the soil pollutant is reduced to be below a certain concentration, the effect can be gradually reduced, and the whole restoration period is prolonged. Causing a great deal of energy and manpower waste.
Disclosure of Invention
The invention aims to provide a soil remediation system and a method for enhancing a thermal desorption effect, and aims to reduce energy waste and improve soil remediation efficiency. The process route of the invention is to inject the residual heat and power of the flue gas into the underground again through the gas injection well and form a flue gas loop with the extraction well. On one hand, the mass and heat transfer between the waste heat of the flue gas and the soil can be fully utilized, and the temperature rise of the soil is accelerated; on the other hand, the flue gas contains a large amount of water vapor and carbon dioxide to enhance the flow of pollutants in the soil, thereby enhancing the extraction efficiency.
The high-temperature flue gas after indirect heat conduction through the heating well and the soil has the temperature of about 200-300 ℃, and the traditional gas thermal desorption technology directly discharges the heat directly, so that energy waste is caused, the flue gas is injected into underground soil through the gas injection well, the flue gas is in direct contact with the soil, the waste heat of the flue gas can be fully utilized, and the temperature rise of the soil is further accelerated. Meanwhile, most of the fuel gas is hydrocarbon at present, most of the main products after combustion are water vapor and carbon dioxide, the capacity of water phase and gas phase pollutants can be increased by injecting the fuel gas into the soil, NAPLs can migrate to the water phase and the gas phase, the extraction efficiency of the whole pollutants is improved, and the construction period of the whole repair project is shortened. When the concentration of the soil pollutants is reduced to be below a certain concentration, the four-phase pollutants tend to be stable, so that the extraction efficiency is reduced, the concentrations of the gas phase and the water phase are improved, and the four-phase balance can be effectively broken, so that the tailing phenomenon in soil remediation is solved.
In order to achieve the purpose, the invention adopts the following technical scheme:
a soil remediation system for strengthening thermal desorption effect comprises a heating well, an extraction well and a gas injection well which are buried below the surface layer of soil to be remediated, a heat supply device for providing heat for the heating well, a vacuum pump for extracting gas in the extraction well and a pollutant treatment device for treating gas extracted by the vacuum pump; the heating well is an inner sleeve type heating well and an outer sleeve type heating well, and smoke generated by the heat supply device enters from an inlet at the upper part of the inner sleeve and enters the outer sleeve from an outlet at the bottom of the inner sleeve; the upper part of the outer sleeve is provided with a flue gas outlet communicated with a gas injection well.
Further, the extraction well is a vertical extraction well.
Furthermore, the extraction well is a combination of a vertical extraction well and a horizontal extraction well, quartz sand layers are arranged on the outer sides of the extraction well and the gas injection well, and the quartz sand layer on the outer side of the horizontal extraction well is respectively contacted with the quartz sand layer on the outer side of the gas injection well and the quartz sand layer on the outer side of the vertical extraction well.
Furthermore, an aeration pipe is arranged in the gas injection well, and an inlet at the upper part of the aeration pipe is communicated with a flue gas outlet of the outer sleeve.
Furthermore, the distance between the adjacent slots of the well walls of the extraction well and the gas injection well is 10-1000 mm.
Furthermore, the outer sides of the extraction well and the gas injection well are wrapped with 50-300-mesh stainless steel wire nets.
Further, the heat supply device comprises a fan, a burner and a tube well; the fan is used for providing air required by combustion and providing wind pressure as a power source; the combustor is used for mixing and igniting gas and air and combusting in the tube well; high-temperature flue gas generated by the tube well enters the heating well.
Further, a barrier layer covers the soil to be repaired.
Further, the pollutant treatment device comprises a gas-liquid separator, an exhaust gas treatment device and a sewage treatment device; the inlet of the gas-liquid separator is connected with the outlet of the vacuum pump, and the gas outlet and the liquid outlet of the gas-liquid separator are respectively connected with the waste gas treatment device and the sewage treatment device. The waste gas treatment device is mostly an incinerator, activated carbon, an optoelectronic processor and the like, and the sewage treatment device is a sedimentation tank, an adjusting tank, a bubble generator, an ozone generator, a Fenton tank and the like, and is mainly selected and combined for use according to the components of underground pollutants.
The soil remediation method for enhancing the thermal desorption effect based on the soil remediation system with the vertical extraction well as the extraction well comprises the following steps:
step 1: smoke generated by the heat supply device sequentially enters the heating well and the gas injection well, so that the soil to be repaired around the heating well and the gas injection well is heated, and pollutants adsorbed on the soil are desorbed from the soil;
step 2: under the action of a vacuum pump, smoke in the gas injection well sequentially passes through a slit of the gas injection well, soil between the gas injection well and the vertical extraction well and a slit of the vertical extraction well, and finally enters the vertical extraction well; pollutants in the soil also pass through the slots of the vertical extraction well and enter the vertical extraction well;
and step 3: and extracting the smoke and the pollutants in the vertical extraction well into a pollutant treatment device for harmless treatment.
The soil remediation method for enhancing the thermal desorption effect based on the soil remediation system with the extraction well combined with the horizontal extraction well and the vertical extraction well comprises the following steps of:
step 1: smoke generated by the heat supply device sequentially enters the heating well and the gas injection well, so that the soil to be repaired around the heating well and the gas injection well is heated, and pollutants adsorbed on the soil are desorbed from the soil;
step 2: under the action of a vacuum pump, smoke in the gas injection well sequentially passes through a slit of the gas injection well, a quartz sand layer contacted with the outer sides of the gas injection well and the horizontal extraction well and a slit of the horizontal extraction well, then a part of smoke is extracted out of the horizontal extraction well, and the other part of smoke sequentially passes through the slit of the horizontal extraction well, the quartz sand layer contacted with the outer sides of the horizontal extraction well and the vertical extraction well and enters the vertical extraction well; pollutants in the soil also pass through the slot of the extraction well and enter the extraction well; extracting the smoke and the pollutants in the extraction well into a pollutant treatment device for harmless treatment;
and step 3: when the temperature of the soil rises to 70-90 ℃, closing a valve on a channel between the horizontal extraction well and the vacuum pump, and under the action of the vacuum pump, enabling the flue gas in the gas injection well to sequentially pass through a slit of the gas injection well, a quartz sand layer outside the gas injection well, the soil between the gas injection well and the vertical extraction well, the quartz sand layer outside the vertical extraction well and the slit of the vertical extraction well, and finally enter the vertical extraction well; pollutants in the soil also pass through the slots of the vertical extraction well and enter the vertical extraction well; and extracting the smoke and pollutants in the vertical extraction well into a pollution treatment device for harmless treatment.
Has the advantages that: compared with the prior gas thermal desorption technology, the invention has the advantages that:
1. the heat of the flue gas after combustion is fully utilized, and no energy waste is caused;
2. the flue gas after burning is taken as a clean product, secondary pollution can not be generated after the flue gas is injected underground, the extraction efficiency can be further improved by utilizing the product characteristics, and the trailing phenomenon of the existing gas thermal desorption is solved;
3. compared with the existing gas thermal desorption technology, the method can reduce a large amount of gas and shorten the whole repair period.
Drawings
FIG. 1 is a schematic structural view of example 1;
reference numbers in the figures: 1. heating well, 2, contaminated soil, 3, barrier layer, 4, fan, 5, burner, 6, tube well, 7, gas injection well, 8, vacuum pump, 9 and vertical extraction well.
FIG. 2 is a schematic structural view of example 2;
reference numbers in the figures: 1. heating well, 2, contaminated soil, 3, barrier layer, 4, fan, 5, burner, 6, fan, 7, gas injection well, 8, vacuum pump, 9 and vertical extraction well.
FIG. 3 is a schematic structural view of example 3;
reference numbers in the figures: 1. heating well, 2, polluted soil, 3, barrier layer, 4, fan, 5, burner, 6, tube well, 7, gas injection well, 8, vacuum pump, 9, vertical extraction well, 10, horizontal extraction well, 11, quartz sand and other coarse particle substances.
FIG. 4 is a schematic structural view of example 4;
reference numbers in the figures: 1. heating well, 2, polluted soil, 3, barrier layer, 4, fan, 5, burner, 6, tube well, 7, gas injection well, 8, aeration tube, 9, vacuum pump, 10, vertical extraction well, 11, horizontal extraction well, 12, quartz sand and other coarse particle substances.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
Example 1
Example 1 mainly aims at low water content (0-15%) of polluted soil and good permeability (permeability coefficient k is more than or equal to 10)-8cm2) The specific implementation conditions of the site are as follows:
as shown in figure 1, air is blown into a burner 5 through a primary air port of a positive pressure fan 4 to be mixed with gas and then combusted in a tube well 6. The lower end overgrate air entry is used for cooling whole tube-shaft 6, and the flue gas after through inside and outside bushing type heating well 1 and the indirect heat conduction cooling of contaminated soil 2 is leading-in gas injection well 7, and gas injection well 7 is slotted at a certain distance interval, and the flue gas gets into contaminated soil 2 through the notch, through with contaminated soil 2 heat and mass transfer, utilizes tail end vacuum pump 8 through extracting well 9 with the pollutant in the contaminated soil 2 at last.
The positive pressure fan provides air quantity and air pressure required by the combustor for providing power for the flue gas to enter the soil, and the vacuum pump of the extraction well forms pressure difference with the gas injection well, so that the flow of the flue gas is forcibly provided. According to the embodiment 1, the filling of coarse particles such as quartz sand of a gas injection well and an extraction well is abandoned, and the arrangement of horizontal extraction wells is reduced, so that the method is more suitable for polluted sites with deep underground water level and good soil permeability in northern areas of China.
Example 2
Example 2 mainly aims at low water content (0-15%) and good permeability (permeability coefficient k is greater than or equal to 10) of polluted soil-8cm2) The specific implementation conditions of the site are as follows:
as shown in fig. 2, air is taken in from the primary tuyere through the intermediately disposed blower 6 to provide the amount of air required for combustion in the combustor 4. The lower end overgrate air inlet is used for cooling the whole tube well 5, the flue gas after being indirectly heat-conducting and cooled through the inner and outer sleeve type heating wells 1 and the polluted soil 2 is pressurized through the middle fan 6 and then pressed into the gas injection well 7, the gas injection well 7 is grooved at intervals, the flue gas enters the soil 2 through the notches, and finally the flue gas and pollutants in the soil 2 utilize the tail end vacuum pump 8 through the extraction well 9 through heat and mass transfer with the soil 2.
The pressure of the gas injection well is enhanced by a fan between the heating well and the gas injection well to overcome the resistance between the gas injection well and the soil, and example 2 is mainly used as an alternative of example 1 for a contaminated soil field with lower water content and better permeability.
Example 3
Example 3 mainly addresses the poor permeability of contaminated soil (permeability coefficient k less than 10)-8cm2) As shown in fig. 3, the heating well 1, the horizontal extraction well 10, the vertical extraction well 9, and the gas injection well 7 are drilled or buried below the surface layer of the contaminated soil 2, coarse particulate matter 11 such as quartz sand is buried around the gas injection well 7 and the extraction well, and the contaminated soil 2 is covered with the barrier layer 3. The fan 4 is used for providing air required by combustion and providing air pressure as a power source, fuel gas is mixed with the air through the combustor 5 and ignited, high-temperature flue gas generated by combustion in the tube well 6 enters the heating well 1, and heat is transferred with soil through the tube wall of the heating well 1, so that the soil temperature is improved. Then the flue gas is injected into the gas injection well 7 and enters the polluted soil 2 through the slots on the gas injection well 7. The flue gas passes through gaps in the soil, is extracted to the ground surface from the extraction well together with the pollutants by the vacuum pump 8, then is subjected to gas-liquid separation, and further processes the water and the gas containing the pollutants, so that the standard emission is achieved.
The arrangement of the heating well, the extraction well and the gas injection well is not limited to in-situ or ex-situ, and the depth and the position of each heating well, each extraction well and each gas injection well are determined according to the on-site construction and the pollution earthwork amount.
Coarse granular substances such as quartz sand and the like are buried around the extraction well and the gas injection well, the permeability of the gas injection well and the extraction well is mainly enhanced, and corresponding landfill substances, particle sizes and quantity are selected according to the soil permeability and the pollutant condition.
The relative distance between the gas injection well and the vertical extraction well is kept between 0.5 and 6m, and the relative distance is flexibly adjusted according to the pressure difference between the fan and the vacuum pump.
The parallel extraction well is used as an initial flue gas conduction channel, the distance between the parallel extraction well and the gas injection well and the distance between the parallel extraction well and the vertical extraction well are kept between 0 and 1 meter, and whether the parallel extraction well is arranged or not and the corresponding distance are considered according to the soil permeability.
The slotting distance of the extraction well and the gas injection well is 10-1000 mm, and 50-300-mesh stainless steel wire nets can be selected to cover the extraction well and the gas injection well according to the soil property.
The position of the fan can be adjusted according to the property of the polluted soil; and a high-pressure fan and an air compressor can also be selected as air power sources. The wind pressure of the selected fan ensures that the pressure of a gas outlet in the combustor is larger than the pressure in the combustor, and the stability of gas outlet is ensured.
The temperature of the flue gas entering the gas injection well is kept between 110 ℃ and 450 ℃ so as to ensure that the water in the flue gas is kept in a water vapor state.
The tail end of the pipe well is provided with smoke monitoring to ensure sufficient combustion and ensure that secondary pollution cannot be generated when the pipe well is supplied underground.
The specific implementation conditions are as follows:
air is sucked from the primary air port by the fan 4 to provide the amount of air required for combustion in the burner 5. The lower end secondary air inlet is used for cooling the whole tube well 6, flue gas after indirect heat conduction and cooling through the inner sleeve type heating well 1 and the outer sleeve type heating well 2 is introduced into the gas injection well 7, the gas injection well 7 is provided with grooves at intervals, the flue gas enters the quartz sand and the coarse particle materials 11 through the grooves, an initial flue gas channel is composed of the gas injection well 7, the horizontal extraction well 10, the vertical extraction well 9, the quartz sand and the coarse particle materials 11 and the vacuum pump 8, heat and mass transfer is carried out between the formed flue gas channel and the soil, the permeability of the soil is gradually improved along with the increase of the temperature of the soil, a valve between the horizontal extraction well 10 and the vacuum pump 8 is closed, so that flue gas channels of the gas injection well 7, the polluted soil 2 and the vertical extraction well 9 are formed, and the heat transfer of the polluted soil and the extraction rate of pollutants are enhanced.
Example 3 the piezoresistive problem for the contaminated soil with poor permeability is circumvented by adding landfill such as quartz sand and a horizontal extraction well, and example 3 can be used for a contaminated soil field with poor permeability.
Example 4
Example 4 mainly aims at shallow groundwater level (after the extraction well is inserted into the soil, the groundwater level is indicated by the groundwater gushing), and poor permeability (the permeability coefficient k is less than 10)-8cm2) The specific implementation conditions of the site are as follows:
as shown in fig. 4, air is taken in from the primary tuyere by the fan 4 to provide the amount of air required for combustion in the burner 5. The lower secondary air inlet is used for cooling the whole pipe well 6, the flue gas after being indirectly heat-conducting cooled through the inner and outer sleeve type heating well 1 and the polluted soil 2 is led into the aeration pipe 8, the gas injection well 7 and the aeration pipe 8 form an inner and outer sleeve structure, the gas injection well 7 is grooved at intervals, underground water enters the gas injection well 7 through the grooves, the aeration pipe 8 is directly buried below the underground water level, the initial flue gas forms an aeration state with the underground water through the aeration well 8, so that the flue gas and the underground water are fully subjected to heat exchange, pollutants are taken away from the underground water, then the flue gas enters tail gas treatment equipment through the horizontal extraction well 11, quartz sand, coarse granular substances 11 and the vertical extraction well 10, along with the temperature rise and the reduction of the underground water level line, a valve between the horizontal extraction well 11 and the vacuum pump 9 can be closed, so as to form a flue gas channel of the gas injection well 7, the polluted soil 2 and the vertical extraction well 10, enhancing the heat transfer of the polluted soil and the extraction rate of the pollutants.
Example 4 is to add an aeration pipe on the basis of example 3 to strengthen the treatment of south polluted soil with heavy water content and shallow underground water level.
Claims (10)
1. A soil remediation system for enhancing thermal desorption effect is characterized by comprising a heating well, an extraction well and a gas injection well which are buried below the surface layer of soil to be remediated, a heat supply device for providing heat for the heating well, a vacuum pump for extracting gas in the extraction well and a pollutant treatment device for treating the gas extracted by the vacuum pump; the heating well is an inner sleeve type heating well and an outer sleeve type heating well, and smoke generated by the heat supply device enters from an inlet at the upper part of the inner sleeve and enters the outer sleeve from an outlet at the bottom of the inner sleeve; the upper part of the outer sleeve is provided with a flue gas outlet communicated with a gas injection well.
2. The soil remediation system with enhanced thermal desorption effect of claim 1, wherein the extraction well is a vertical extraction well.
3. The soil remediation system for enhancing thermal desorption effect as claimed in claim 1, wherein the extraction well is a combination of a vertical extraction well and a horizontal extraction well, quartz sand layers are disposed outside the extraction well and the gas injection well, and the quartz sand layer outside the horizontal extraction well is in contact with the quartz sand layer outside the gas injection well and the quartz sand layer outside the vertical extraction well, respectively.
4. The soil remediation system for enhancing thermal desorption effect of claim 1, wherein an aerator pipe is arranged in the gas injection well, and an upper inlet of the aerator pipe is communicated with the flue gas outlet of the outer sleeve.
5. The soil remediation system for enhancing thermal desorption effect of claim 1, wherein the distance between the adjacent slots of the extraction well and the gas injection well is 10 mm-1000 mm.
6. The soil remediation system for enhancing thermal desorption effect as claimed in claim 1, wherein the extraction well and the gas injection well are externally wrapped with 50-300 mesh stainless steel wire mesh.
7. The soil remediation system for enhancing thermal desorption of claim 1, wherein the heat supply device comprises a fan, a burner and a tube well; the fan is used for providing air required by combustion and providing wind pressure as a power source; the combustor is used for mixing and igniting gas and air and combusting in the tube well; high-temperature flue gas generated by the tube well enters the heating well.
8. The soil remediation system with enhanced thermal desorption effect of claim 1, wherein the soil to be remediated is covered with a barrier layer.
9. The soil remediation system of claim 2, further comprising a thermal desorption enhancing soil remediation method, the thermal desorption enhancing soil remediation method comprising the steps of:
step 1: smoke generated by the heat supply device sequentially enters the heating well and the gas injection well, so that the soil to be repaired around the heating well and the gas injection well is heated, and pollutants adsorbed on the soil are desorbed from the soil;
step 2: under the action of a vacuum pump, smoke in the gas injection well sequentially passes through a slit of the gas injection well, soil between the gas injection well and the vertical extraction well and a slit of the vertical extraction well, and finally enters the vertical extraction well; pollutants in the soil also pass through the slots of the vertical extraction well and enter the vertical extraction well;
and step 3: and extracting the smoke and the pollutants in the vertical extraction well into a pollutant treatment device for harmless treatment.
10. A soil remediation method for enhancing thermal desorption effect based on the soil remediation system of claim 3, comprising the steps of:
step 1: smoke generated by the heat supply device sequentially enters the heating well and the gas injection well, so that the soil to be repaired around the heating well and the gas injection well is heated, and pollutants adsorbed on the soil are desorbed from the soil;
step 2: under the action of a vacuum pump, smoke in the gas injection well sequentially passes through a slit of the gas injection well, a quartz sand layer contacted with the outer sides of the gas injection well and the horizontal extraction well and a slit of the horizontal extraction well, then a part of smoke is extracted out of the horizontal extraction well, and the other part of smoke sequentially passes through the slit of the horizontal extraction well, the quartz sand layer contacted with the outer sides of the horizontal extraction well and the vertical extraction well and enters the vertical extraction well; pollutants in the soil also pass through the slot of the extraction well and enter the extraction well; extracting the smoke and the pollutants in the extraction well into a pollutant treatment device for harmless treatment;
and step 3: when the temperature of the soil rises to 70-90 ℃, closing a valve on a channel between the horizontal extraction well and the vacuum pump, and under the action of the vacuum pump, enabling the flue gas in the gas injection well to sequentially pass through a slit of the gas injection well, a quartz sand layer outside the gas injection well, the soil between the gas injection well and the vertical extraction well, the quartz sand layer outside the vertical extraction well and the slit of the vertical extraction well, and finally enter the vertical extraction well; pollutants in the soil also pass through the slots of the vertical extraction well and enter the vertical extraction well; and extracting the smoke and pollutants in the vertical extraction well into a pollution treatment device for harmless treatment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110503938.5A CN113172084A (en) | 2021-05-10 | 2021-05-10 | Soil remediation system and method for enhancing thermal desorption effect |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110503938.5A CN113172084A (en) | 2021-05-10 | 2021-05-10 | Soil remediation system and method for enhancing thermal desorption effect |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113172084A true CN113172084A (en) | 2021-07-27 |
Family
ID=76928814
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110503938.5A Pending CN113172084A (en) | 2021-05-10 | 2021-05-10 | Soil remediation system and method for enhancing thermal desorption effect |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113172084A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114393019A (en) * | 2022-01-20 | 2022-04-26 | 北京高能时代环境技术股份有限公司 | System for in-situ soil remediation and risk management and control of organochlorine pesticide contaminated site |
| CN115055504A (en) * | 2022-06-29 | 2022-09-16 | 煜环环境科技有限公司 | Microbial leaching reaction device and soil remediation method |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008272720A (en) * | 2007-04-05 | 2008-11-13 | Kenzo Takahashi | Polluted soil treatment system using waste heat |
| CN107552554A (en) * | 2017-09-26 | 2018-01-09 | 上海格林曼环境技术有限公司 | Extracting condensation and Separate System of Water-jet for the thermal desorption reparation of contaminated site original position |
| CN107685072A (en) * | 2017-09-26 | 2018-02-13 | 上海格林曼环境技术有限公司 | A kind of method of concentrated combustion formula original position thermal desorption reparation for contaminated site |
| CN108339842A (en) * | 2018-02-11 | 2018-07-31 | 中国科学院武汉岩土力学研究所 | A kind of soil vapor extraction system and method for combining injection with hot-air based on water vapour |
| CN109351766A (en) * | 2018-11-30 | 2019-02-19 | 中冶南方都市环保工程技术股份有限公司 | Contaminated soil combustion gas original position thermal desorption repair system |
| CN110695071A (en) * | 2019-09-04 | 2020-01-17 | 中国地质大学（北京） | In-situ heat injection system and process for composite organic pollution site |
| CN111250524A (en) * | 2020-01-15 | 2020-06-09 | 北京石油化工学院 | Gas thermal desorption-steam enhanced gas-phase extraction in-situ coupling repair method for composite organic pollution site |
| CN112588809A (en) * | 2020-12-03 | 2021-04-02 | 江苏大地益源环境修复有限公司 | Electroosmosis-enhanced precipitation and in-situ thermal desorption soil remediation system and method |
-
2021
- 2021-05-10 CN CN202110503938.5A patent/CN113172084A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008272720A (en) * | 2007-04-05 | 2008-11-13 | Kenzo Takahashi | Polluted soil treatment system using waste heat |
| CN107552554A (en) * | 2017-09-26 | 2018-01-09 | 上海格林曼环境技术有限公司 | Extracting condensation and Separate System of Water-jet for the thermal desorption reparation of contaminated site original position |
| CN107685072A (en) * | 2017-09-26 | 2018-02-13 | 上海格林曼环境技术有限公司 | A kind of method of concentrated combustion formula original position thermal desorption reparation for contaminated site |
| CN108339842A (en) * | 2018-02-11 | 2018-07-31 | 中国科学院武汉岩土力学研究所 | A kind of soil vapor extraction system and method for combining injection with hot-air based on water vapour |
| CN109351766A (en) * | 2018-11-30 | 2019-02-19 | 中冶南方都市环保工程技术股份有限公司 | Contaminated soil combustion gas original position thermal desorption repair system |
| CN110695071A (en) * | 2019-09-04 | 2020-01-17 | 中国地质大学（北京） | In-situ heat injection system and process for composite organic pollution site |
| CN111250524A (en) * | 2020-01-15 | 2020-06-09 | 北京石油化工学院 | Gas thermal desorption-steam enhanced gas-phase extraction in-situ coupling repair method for composite organic pollution site |
| CN112588809A (en) * | 2020-12-03 | 2021-04-02 | 江苏大地益源环境修复有限公司 | Electroosmosis-enhanced precipitation and in-situ thermal desorption soil remediation system and method |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114393019A (en) * | 2022-01-20 | 2022-04-26 | 北京高能时代环境技术股份有限公司 | System for in-situ soil remediation and risk management and control of organochlorine pesticide contaminated site |
| CN115055504A (en) * | 2022-06-29 | 2022-09-16 | 煜环环境科技有限公司 | Microbial leaching reaction device and soil remediation method |
| CN115055504B (en) * | 2022-06-29 | 2023-06-16 | 煜环环境科技有限公司 | Microorganism leaching reaction device and soil restoration method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN206731803U (en) | Contaminated site In-situ reaction formula thermal desorption repair system | |
| US10940514B2 (en) | In-situ thermal desorption system, in-situ thermal desorption-oxidation repair system and repair method | |
| CN107685073B (en) | Centralized combustion type in-situ thermal desorption repairing device for polluted site | |
| CN203343163U (en) | Polluted soil in-situ combined desorption restoration system | |
| CN107350278B (en) | In-situ remediation system and method for cooperatively removing organic pollutants in soil and underground water | |
| CN109351766B (en) | Contaminated soil gas normal position thermal desorption repair system | |
| CN204710846U (en) | A kind of steam strengthening thermal desorption and gas phase extracting soil repair system | |
| CN107685072B (en) | Centralized combustion type in-situ thermal desorption restoration method for polluted site | |
| KR101927947B1 (en) | In Situ Treatment Apparatus applying Pneumatic Fracturing and Forced Extraction for oil contaminated Soil | |
| CN108746178A (en) | A kind of energy saving thermal desorption processing unit in situ and processing method of oil pollution soil | |
| CN108906869A (en) | A kind of contaminated soil in-situ heat repair system and method using distributed energy | |
| CN113172084A (en) | Soil remediation system and method for enhancing thermal desorption effect | |
| CN102228900A (en) | In situ integrated restoring system and method of petroleum polluted soil | |
| CN110695071A (en) | In-situ heat injection system and process for composite organic pollution site | |
| CN103551373A (en) | System and method for removing organic pollutants in soil employing microwave-assisted soil vapor extraction (SVE) | |
| CN214488279U (en) | Organic contaminated site normal position thermal desorption well position layout structure | |
| CN104724818B (en) | A kind of carbon tetrachloride piece-rate system and separating technology thereof | |
| CN111250524A (en) | Gas thermal desorption-steam enhanced gas-phase extraction in-situ coupling repair method for composite organic pollution site | |
| CN110614266A (en) | Heap thermal desorption treatment system for repairing organic contaminated soil | |
| CN105417769B (en) | A kind of laboratory carbon tetrachloride separating treatment system and its handling process | |
| CN104815840A (en) | Method and system for contaminant removal by injecting high-temperature dry gas into soil | |
| CN107983759A (en) | Organic polluted soil original position thermal desorption prosthetic device | |
| CN114733895A (en) | Pollute soil gas normal position thermal desorption restoration equipment | |
| CN213613303U (en) | Heat-enhanced multi-phase extraction system | |
| CN207872723U (en) | A kind of low temperature pyrogenation desorption soil contaminated by crude oil prosthetic device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210727 |