Combined refuse landfill gas pollutant in-situ biological window treatment device and method

Abstract

The invention discloses a combined refuse landfill gas pollutant in-situ biological window treatment device and method, and belongs to the technical field of solid waste treatment and disposal, the combined refuse landfill gas pollutant in-situ biological window treatment device comprises a window top, at least two treatment boxes, a base and an equipment box, and the window top, the treatment boxes and the base are arranged from top to bottom and detachably connected; the treatment boxes are box bodies with open tops, the peripheral walls of the box bodies are sealing plates, the bottom walls of the box bodies are perforated plates, and the treatment boxes are filled with light inert fillers and main body fillers; the treatment box connected with the window top is provided with a water distribution device, and the rest treatment boxes are provided with water distribution devices and gas injection devices; the base is a box body with an open top, the peripheral wall of the box body is a sealing plate, the bottom wall of the box body is a punching plate, and the base is filled with light inert filler; a water pump, an air blower, a storage battery and a water collecting barrel are arranged in the equipment box. The device is simple in structure, the treatment boxes can be combined according to the emission amount of gas pollutants in different landfill areas, operation is convenient, and the device can be applied to landfill gas pollutant removal in various scenes.

Description

Technical Field

[0001] The invention belongs to the technical field of solid waste treatment and disposal, and specifically relates to a combined landfill gas pollutant in-situ biological window treatment device and method. Background Art

[0002] In landfills, garbage is decomposed by microorganisms to produce landfill gas, the main components of which are methane and CO2, both of which are greenhouse gases. In particular, the greenhouse effect of methane is 20 to 30 times that of CO2. Landfills are the third largest source of anthropogenic methane emissions, with an emission of about 60 to 69 Tg of methane per year, accounting for about 12% of the world's total anthropogenic emissions. Landfill gas also contains many trace gases, including NH3, H2S and volatile organic compounds, which are the main substances causing odor pollution in landfills and seriously affect the lives of surrounding residents. In particular, many volatile organic compounds such as toluene and benzene are "carcinogenic, teratogenic, and mutagenic". At present, many small and medium-sized old landfills and informal landfills are not equipped with landfill gas collection devices. Even if landfills are equipped with landfill gas recovery and utilization devices, there are still problems of low collection efficiency and poor economic feasibility. Therefore, it is necessary to safely, efficiently and greenly treat the large amount of landfill gas generated by landfills.

[0003] The landfill cover soil layer is the environmental interface of the "landfill gas-atmosphere" system and the last barrier to control the entry of methane, ammonia, sulfur compounds, trichloroethylene, toluene and other volatile gas pollutants in the landfill gas into the atmosphere. The "biofilter system" of the cover soil layer is the key technology for controlling gas pollutants in landfills. Existing research on the purification effect of the cover soil layer of landfills mainly focuses on screening different cover materials and strengthening the methane oxidation performance of the cover soil layer. For example, the Chinese patent document with publication number CN115213190A discloses the use of incineration slag containing methane oxidizing bacteria as a cover material; the Chinese patent document with publication number CN106318990A discloses the use of exogenously added microbial signal molecules as methane oxidizing agents to reduce the methane content in the landfill. However, the above method requires the construction of the entire cover layer, which has the problems of large engineering workload and high design requirements. Due to the heterogeneity of landfill waste and the regionality of landfill, different areas release different gaseous pollutants. At the same time, some point areas such as gas exhaust pipes, collection pipes, and high-density polyethylene film connections of the impermeable layer have weak sealing properties, so landfill gas pollutants usually escape in large quantities, resulting in high regional methane and other trace pollutant emission concentrations (1 to 2 data levels higher than the conventional landfill coverage area). However, the above-mentioned traditional single landfill cover layer and its modified biological cover layer cannot meet the removal of gaseous pollutants in high-hotspot areas.

[0004] Therefore, it is necessary to develop an in-situ biological treatment device for landfill gas pollutants to solve the technical defects of the existing landfill cover soil layer treatment of gas pollutants, which cannot take into account different areas and has poor treatment effect. Summary of the invention

[0005] In order to address the shortcomings of the prior art, the present invention provides a combined in-situ biological window treatment device for landfill gas pollutants, which can improve the in-situ purification performance of high-hot spot emission areas of landfill gas pollutants such as gas exhaust pipes, gas collection pipes, and connections between high-density polyethylene (HDPE) membranes of anti-seepage layers, thereby reducing gas pollutant emissions from landfills.

[0006] The specific technical solutions adopted are as follows:

[0007] A combined landfill gas pollutant in-situ biological window treatment device comprises a window top 1, at least two treatment boxes, a base 5 and an equipment box 6, wherein the window top 1, the treatment box and the base 5 are arranged from top to bottom, and the window top 1 and the treatment box, the treatment boxes and the treatment box and the base 5 are connected in a detachable manner and the gas can be exchanged;

[0008] The processing boxes are all open-top boxes, the peripheral walls of the boxes are sealing plates, and the bottom walls are perforated plates 9. Lightweight inert fillers 12 and main body fillers 13 are filled in the processing boxes, the lightweight inert fillers 12 are located at the bottom layer, and the main body fillers 13 are located at the upper layer; the processing box connected to the window top 1 is provided with a water distribution device to maintain the humidity of the filler, and the remaining processing boxes are provided with a water distribution device and an air injection device to maintain the humidity of the filler and regulate the oxygen concentration;

[0009] The base 5 is a box with an open top, the peripheral wall of the box is a sealing plate, the bottom wall is a punching plate 9, and the base is filled with a light inert filler 12;

[0010] The equipment box 6 is equipped with a water pump 15, a blower 16, a battery 17 and a water collecting bucket 31. The battery 17 supplies energy to the equipment, the water collecting bucket 31 and the water pump 15 provide water for the water distribution device, and the blower 16 provides air for the gas injection device. The water pump 15 and the blower 16 are started and stopped by a time switch 21.

[0011] Preferably, the window top 1 adopts a sloping top, a bayonet U-shaped groove is provided at the bottom of the window top 1, an insertion plate is provided at the top of each processing box, a bayonet U-shaped groove is provided at the bottom, and an insertion plate is provided at the top of the base 5. The window top 1 and the processing box, the processing boxes, and the processing box and the base 5 are all connected through the cooperation of the bayonet U-shaped groove and the insertion plate.

[0012] Further preferably, the slope of the window top 1 is 15 to 45°, a bayonet U-shaped groove is set at 20 to 50 cm from the bottom of the window top 1, the width of the bayonet U-shaped groove is 1 to 4 cm, and the depth is 2 to 8 cm. PP perforated plate enclosures are set on both sides of the window top 1 extending inward by 20 to 40 cm, and the hole diameter of the perforated plate 30 on one side of the window top 1 is 1 to 5 cm.

[0013] Optionally, the processing box includes a top processing box 2, a middle processing box 3 and a bottom processing box 4, and the window top 1, the top processing box 2, the middle processing box 3, the bottom processing box 4 and the base 5 are arranged from top to bottom.

[0014] Preferably, the depth of the processing box is 50-80 cm, the length and width are both 1-5 m, and the hole diameter of the punching plate 9 is 5-10 mm.

[0015] Preferably, a water distribution device is provided on the top of the peripheral wall of the treatment box connected to the top of the window 1, and the water distribution device includes a water distribution branch pipe 7 and a sprinkler head 8; the bottom wall of the treatment box connected to the top of the window 1 serves as the top wall of the next treatment box, and a water distribution device is provided on the inner top wall of the next treatment box, and the water distribution device includes a water distribution branch pipe 7 and a sprinkler head 8, and a gas injection device is provided on the inner bottom wall, and the gas injection device includes a gas injection branch pipe 10, and a hole is opened on the gas injection branch pipe 10. The subsequent treatment boxes are arranged in the same way, and the water distribution device is not provided on the outer bottom wall of the last treatment box.

[0016] Furthermore, the water distribution branch pipe 7 and the gas injection branch pipe 10 are fixed to the punching plate 9 by means of a fixing ring 11 , and the outer wall between the layers of the processing box is further fixed by means of a buckle 14 .

[0017] Furthermore, the electronic control valve 20 is used to control the differences in water distribution and gas injection in different treatment boxes. The water distribution branch pipe 7 is connected to the water distribution main pipe 18 through the electronic control valve 20. The water distribution main pipe 18 is directly connected to the water pump 15. The water distribution main pipe and the water distribution branch pipe are made of polyethylene PVC pipes with a diameter of 1.5 to 3 cm, and the humidity of the filler is maintained at 30% to 50%; the gas injection branch pipe 10 is connected to the gas injection main pipe 19 through the electronic control valve 20. The gas injection main pipe 19 is directly connected to the blower 16. The gas injection main pipe 19 and the gas injection branch pipe 10 are made of polyethylene PVC pipes with a diameter of 1.5 to 2.5 cm. The gas injection branch pipe 10 has small holes with a diameter of 3 to 5 mm on both sides at a vertical angle of 45° upward, and the hole spacing is 3 to 5 mm. The gas injection branch pipes 10 are spaced 50 to 100 cm apart to adjust the oxygen concentration in the treatment box to be >3%.

[0018] Furthermore, the water distribution branch pipe 7 on the peripheral wall of the treatment box connected to the window top 1 is set 5 to 10 cm away from the top, and a spray head 8 is arranged in the middle of the water distribution branch pipe 7. A plurality of spray heads 8 are arranged on the water distribution branch pipe 7 of the remaining treatment boxes at an equal interval of 50 to 100 cm. The diameter of the spray head 8 is 0.4 to 1 cm.

[0019] Preferably, the lightweight inert filler 12 is a polyurethane sponge or a Raschig ring filler, and the main filler 13 is a mixed filler of stabilized garbage bio-soil (after the landfill is closed for several years, the easily degradable substances in the garbage are completely or nearly completely degraded, and the landfill reaches a stabilized state, that is, a harmless state. The garbage at this time is called stabilized garbage bio-soil), biochar and garbage incineration slag, wherein the stabilized garbage bio-soil accounts for 90%-98%, the pH value of the mixed filler is 6.5-8.5, and the particle size is ≤6mm.

[0020] Furthermore, the processing box is filled with a light inert filler 12 with a height of 1 to 3 cm, and the rest is the main filler 13 (filling the processing box); the height of the light inert filler 12 filled in the base 5 is 20 to 40 cm.

[0021] The present invention also provides a method for treating landfill gas pollutants, using the combined landfill gas pollutant in-situ biological window treatment device.

[0022] The landfill covering layer structure covers the surface of the garbage layer 27, including a drainage layer 23, an impermeable layer 24, a sub-membrane protective layer 25 and an exhaust layer 26 from top to bottom; for the gas drainage pipe 22 area where the release of gas pollutants in the landfill is relatively high, the combined landfill gas pollutant in situ biological window treatment device is arranged on the impermeable layer 24 (any layer on the impermeable layer 24 can be selected), with the gas drainage pipe 22 as the center, the base 5 and the treatment box are provided with gas drainage pipe 22 through-holes, and the surrounding wall of the treatment box connected to the window top 1 is provided with gas drainage pipe 22 outlet holes; for the landfill gas pollutant release hotspot area without gas drainage pipe (such as the gas leakage point connected to the high-density polyethylene HDPE membrane), the combined landfill gas pollutant in situ biological window treatment device is arranged on the impermeable layer 24 or the exhaust layer 26 at the gas pollutant release hotspot area (any layer on the impermeable layer 24 or the exhaust layer 26 can be selected).

[0023] When the combined landfill gas pollutant in-situ biological window treatment device is applied to a covering layer structure, the combined landfill gas pollutant in-situ biological window treatment device is surrounded by an anti-seepage layer 24, a low-permeability soil layer 28 and a vegetation layer 29 to guide the gas pollutants through the device. The thickness of the anti-seepage layer 24 is 50 to 100 cm, and the thickness of the low-permeability soil layer 28 exceeds 60 cm.

[0024] When the combined landfill gas pollutant in-situ biological window treatment device is applied to the cover layer structure, the number of treatment boxes is designed based on the methane removal amount. The methane purification during the treatment process follows the Michaelis-Menten model, the saturation concentration is ~10%, the maximum methane oxidation rate (Vmax) is 50~120mg / (kg·h); the Michaelis-Menten constant (Ks) is 3~6%.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) Compared with the traditional landfill covering layer and its modified biological covering layer, the combined landfill gas pollutant in situ biological window treatment device of the present invention can achieve the removal of gas pollutants in different in situ landfill areas, especially to solve the problem of high-concentration gas leakage pollution in landfill gas exhaust pipes, release hot spots, covering membrane damaged areas or membrane joints.

[0027] (2) The combined landfill gas pollutant in-situ biological window treatment device of the present invention has a simple structure and can be combined with treatment boxes according to the gas pollutant emissions in different areas. It is easy to operate and has a low cost, and can be widely used in various landfill environments.

[0028] (3) The use of stabilized garbage bio-soil mixed with a small amount of biochar and garbage incineration slag as the main filler has a good effect, which can realize the resource utilization of waste and save costs. In addition, garbage incineration slag can solve the filler acidification problem caused by sulfur-containing odorous gases and their conversion during the treatment process, ensuring that gas pollutants can be removed stably and efficiently.

[0029] (4) The present invention uses a time-controlled switch and an electronic control valve to control the water distribution and gas injection between layers, which can prevent excessive moisture from clogging the filler gaps, improve the water and gas utilization rate of the device, control the humidity and oxygen content in the device, and ensure the main filler's treatment efficiency for gaseous pollutants.

[0030] (5) The combined in-situ biological window treatment device for landfill gas pollutants provided by the present invention not only has a highly efficient oxidation performance for CH4, but also has good adsorption and biodegradation performance for gas pollutants such as H2S, toluene, and methyl mercaptan. The concentration of each gas treated by the device meets the secondary emission requirements of the Pollution Control Standard for Municipal Waste Landfills (GB16889-2008) and the Emission Standard for Odor Pollutants (GB14554-93). BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of the combined landfill gas pollutant in-situ biological window treatment device.

[0032] Figure 2 This is a structural diagram of the top-layer processing box, the middle-layer processing box, the bottom-layer processing box and the base.

[0033] Figure 3 It is the water distribution device distribution diagram of the top-level processing box, the water distribution device distribution diagram of the remaining processing boxes, and the gas injection device distribution diagram.

[0034] Figure 4 This is the window top structure diagram.

[0035] Figure 5 It is a structural diagram of the combined landfill gas pollutant in-situ biological window treatment device when applied to the gas exhaust pipe area.

[0036] Figure 6 This is a diagram showing the treatment effects of the control group and the experimental group on different gaseous pollutants in Example 1.

[0037] Figure 7 This is a diagram showing the treatment effects of the control group and the experimental group on different gaseous pollutants in Example 2.

[0038] Figure 8 This is the measurement result of the gas emission concentration in Example 3.

[0039] Description of the drawings: 1 window top, 2 top layer treatment box, 3 middle layer treatment box, 4 bottom layer treatment box, 5 base, 6 equipment box, 7 water distribution branch pipe, 8 sprinkler head, 9 perforated plate, 10 gas injection branch pipe, 11 fixing ring, 12 lightweight inert filler, 13 main body filler, 14 snap, 15 water pump, 16 blower, 17 battery, 18 water distribution main pipe, 19 gas injection main pipe, 20 electronic control valve, 21 time switch, 22 gas drainage pipe, 23 drainage layer, 24 anti-seepage layer, 25 sub-membrane protective layer, 26 exhaust layer, 27 garbage layer, 28 low permeability soil layer, 29 vegetation layer, 30 side perforated plate, 31 water collecting bucket. DETAILED DESCRIPTION

[0040] The present invention will be further described below in conjunction with the embodiments and drawings. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0041] Example 1

[0042] In this embodiment, the structural schematic diagram of the combined landfill gas pollutant in-situ biological window treatment device is as follows: Figure 1 As shown, it includes six parts: window top 1, top layer processing box 2, middle layer processing box 3, bottom layer processing box 4, base 5 and equipment box 6, wherein the window top 1, top layer processing box 2, middle layer processing box 3, bottom layer processing box 4 and base 5 are arranged from top to bottom, and the equipment box 6 is arranged on the outside of the window top 1, and the above six parts are combined and installed in a detachable manner.

[0043] like Figure 2-4 As shown, the window top 1 adopts a 45° inclined top, and the two sides are extended inward by 20 cm with a PP perforated plate enclosure, i.e., a side perforated plate 30, and a bayonet U-shaped groove is set at 30 cm from the bottom. Three 2m×2m×50cm treatment boxes are stacked in sequence under the window top 1, of which the top treatment box 2 adopts an open-top box body, and a plug plate matching the bayonet U-shaped groove of the window top 1 is set on the top. Water distribution branch pipes 7 and sprinkler heads 8 are set around 5 cm from the top of the top of the box wall. The bottom of the box is a perforated plate 9, and a water distribution branch pipe 7 is set under the perforated plate 9. The water distribution branch pipe 7 is used to distribute water to the middle layer treatment box 3, and a bayonet U-shaped groove is set at the bottom of the top treatment box 2. The middle layer processing box 3 is located below the top layer processing box 2. The middle layer processing box 3 also adopts a box body with an open top. The top is provided with a plug-in plate that matches the bayonet U-shaped groove of the top layer processing box 1. The bottom of the box is a punching plate 9. The punching plate 9 is provided with a gas injection branch pipe 10. The punching plate 9 is provided with a water distribution branch pipe 7. The water distribution branch pipe 7 is used to distribute water to the bottom layer processing box 4. The bottom of the middle layer processing box 3 is provided with a bayonet U-shaped groove. The bottom of the middle layer processing box 3 is located below the bottom layer processing box 4. The bottom layer processing box 4 also adopts a box body with an open top. The top is provided with a plug-in plate that matches the bayonet U-shaped groove of the middle layer processing box 3. The bottom of the box is a punching plate 9. The punching plate 9 is provided with a gas injection branch pipe 10. The bottom of the bottom layer processing box 4 is provided with a bayonet U-shaped groove. The bottom of the bottom processing box 4 is connected to the base 5. The base 5 is an open top box body. The top layer is provided with a plug-in plate that matches the bayonet U-shaped groove of the bottom processing box 4. The surroundings are sealed plates. The base is a punching plate 9. The box body is filled with a light inert filler 12.

[0044] The window top 1, the top layer processing box 2, the middle layer processing box 3, the bottom layer processing box 4 and the base 5 are assembled and installed by means of mutually matching bayonet U-shaped grooves and plug-in plates, and the outer walls between the layers of the processing boxes are further fixed by buckles 14.

[0045] The surrounding walls of the top-layer processing box 1, the middle-layer processing box 2, and the bottom-layer processing box 3 are sealing plates. The water distribution branch pipe 7 and the gas injection branch pipe 10 are fixed in the processing box by a fixing ring 11. Lightweight inert fillers 12 and main fillers 13 are placed on the three processing boxes. The lightweight inert fillers 12 are located at the bottom layer, and the main fillers 13 are located at the upper layer.

[0046] The equipment box 6 is equipped with a water pump 15, a blower 16, a battery 17 and a water collection bucket 31. The water pump 15 and the blower 16 are started and stopped by a timer switch 21. The water pump 15 is directly connected to the water distribution pipe 18. The water pump 15 is powered by the battery 17 to start the water pump 15 to lift the water in the water collection bucket 31 into the water distribution branch pipe 7. The water distribution pipe 18 is vertically arranged on the outer wall of the treatment box. The water distribution pipe 18 is connected to the water distribution branch pipe 7 in the treatment box. An electronic control valve 20 is installed on the top of the water distribution branch pipe 7. The top treatment box 1 A nozzle is arranged in the middle of the water distribution branch pipe 7 on the peripheral wall of the box body, and sprinkler heads are arranged at equal intervals of 50 cm on the water distribution devices of the middle layer processing box 3 and the inner top wall of the bottom layer processing box 4 (the perforated plates of the top layer processing box 1 and the middle layer processing box 3); the blower 16 is directly connected to the gas injection main pipe 19, and the gas injection main pipe 19 is vertically arranged on the outer wall of the processing box. The gas injection main pipe 19 is connected to the gas injection branch pipe 10 in the processing box, and an electronic control valve 20 is installed on the top of the gas injection branch pipe 10. The gas injection branch pipe 1 has gas distribution holes on both sides at a vertical angle of 45° upward.

[0047] The specific parameters and materials of each component are as follows: The combined landfill gas pollutant in-situ biological window treatment device is made of polypropylene PP. The hole diameter on the perforated plate 30 on the top of the window 1 is 2 cm. The width of all bayonet U-shaped grooves is 2 cm and the depth is 4 cm. The hole diameter of all treatment box perforated plates 9 is 5 mm. The gas injection main pipe 19 and the gas injection branch pipe 10 are made of polyethylene PVC pipe with a diameter of 2 cm. The diameter of the gas holes of the gas injection branch pipe 10 is 3 mm, the spacing is 4 mm, and the spacing of the gas injection branch pipe 10 is 70 cm. The water distribution main pipe 18 and the water distribution branch pipe 7 are made of polyethylene PVC pipe with a diameter of 2 cm. The sprinkler head 8 on the water distribution branch pipe 7 has a diameter of 0.6 cm. The light inert filler 12 placed on the gas injection branch pipe is a polyurethane sponge with a thickness of 1 cm. The main filler is a mixed filler of stabilized garbage bio-soil, biochar and garbage incineration slag, of which the stabilized garbage bio-soil accounts for 98%, the biochar accounts for 1%, and the garbage incineration slag accounts for 1%. The pH value of the mixed filler is 6.5-8.5, the moisture content is 30-50%, the particle size is ≤6mm, and the thickness is 50cm, filling the treatment box. The light inert filler 12 filled in the base 5 box body is a polyurethane sponge with a height of 30cm; when using the combined landfill gas pollutant in-situ biological window treatment device, the moisture content in the treatment box is maintained at about 40%, and the oxygen concentration in the treatment box is ensured to be about 7%.

[0048] In this embodiment, the combined landfill gas pollutant in-situ biological window treatment device is used in the gas drainage pipe area of ​​the landfill where the gas pollutant release is relatively high. The landfill cover layer structure covers the surface of the garbage layer 27, and the cover layer structure includes a drainage layer 23, an impermeable layer 24, a sub-membrane protective layer 25 and an exhaust layer 26 from top to bottom; the combined landfill gas pollutant in-situ biological window treatment device is arranged on the impermeable layer 24 (specifically arranged on the drainage layer 23), with the gas drainage pipe 22 as the center, the base 5 and the treatment box are provided with a gas drainage pipe through hole, and the peripheral wall of the treatment box connected to the window top 1 is provided with a gas drainage pipe 22 outlet hole ( Figure 5 ), the combined landfill gas pollutant in-situ biological window treatment device is surrounded by an impermeable layer 24, a low permeability soil layer 28 and a vegetation layer 29 to guide the gas pollutants through the device. The thickness of the impermeable layer is 50 cm, and the low permeability soil layer is a clay layer with a thickness of 80 cm.

[0049] In order to demonstrate the effect of the device of the present invention, standard gases such as methane (CH4), H2S, methyl mercaptan (CH3SH), and toluene (C7H8) were configured to a certain concentration and then continuously introduced into the gas exhaust pipe 22 to simulate gas leakage in the landfill gas exhaust pipe area. At the same time, a conventional soil layer was used as a control group to analyze the removal performance of the device for landfill gas pollutants. The concentrations of CH4, H2S, CH3SH, and C7H8 introduced were 50%, 714286 mg / m 3 , 2000mg / m 3 and 2000mg / m 3 The gas flow rate in the gas exhaust pipe is 10L / h. The measurement results of the gas concentration in the device in this embodiment and the conventional soil layer are as follows: Figure 6 shown.

[0050] During the whole experiment, the CH4 emission concentration of the control group was between 28% and 9%, while the CH4 emission concentration of the experimental device was less than 0.08%, which can reach the 0.1% required by the "Pollution Control Standard for Municipal Waste Landfill" (GB 16889-2008). As the experiment progressed, only trace amounts of H2S, CH3SH and C7H8 were detected in the experimental group in the early stage, with average concentrations of 0.03, 0.002 and 0.083 mg / m 3, and then, H2S, CH3SH and C7H8 were not detected, that is, they were below the detection limit. Although the concentrations of H2S, CH3SH and C7H8 in the control group gradually decreased as the experiment progressed, the final concentrations met the emission requirements of the "Emission Standard of Malodor Pollutants" (GB 14554-93). However, compared with the control group, the device of the present invention has a higher purification efficiency, which shows that the device can effectively remove landfill gas pollutants and meet the emission requirements of the "Pollution Control Standard for Domestic Waste Landfills" (GB 16889-2008) and the "Emission Standard of Malodor Pollutants" (GB 14554-93).

[0051] Example 2

[0052] In this embodiment, the combined landfill gas pollutant in-situ biological window treatment device of embodiment 1 is used in the landfill gas pollutant release high gas drainage pipe-free area.

[0053] The combined landfill gas pollutant in-situ biological window treatment device is arranged on the exhaust layer 26 to simulate the emission process of gas pollutants generated by garbage degradation in the landfill. The remaining settings and parameters are the same as those in Example 1.

[0054] In this example, in order to demonstrate the effect of the device of the present invention, the gas emission of landfill waste that lasted for 90 days was measured. At the same time, conventional soil layers were used as blank controls for synchronous sampling and measurement. The results are as follows: Figure 7 shown.

[0055] During the whole experiment, the average gas flow rate of landfill gas produced was 14L / h. Although a large amount of landfill gas was produced by the landfill reactor at the beginning of the experiment, no CH4 was measured in the landfill gas. This is because in the first stage, the landfill waste carries oxygen, and the biodegradation of the organic part belongs to aerobic biodegradation. As the oxygen is exhausted, the degradation of organic matter in the landfill reactor gradually enters the methane stage. In the control group, the CH4 concentration gradually increased from 2.57% to 52.70% from 15 to 50 days, then decreased, and finally maintained at ~13.00%. In contrast, CH4 began to be detected in the experimental group at 20 days, and the CH4 concentration increased from 0.03% to 0.07% from 20 to 50 days, and then gradually decreased. At the end of the experiment, the CH4 concentration was below the detection limit. Similar to the CH4 concentration, the H2S, CH3SH and C7H8 in the control group appeared earlier, showing a trend of first rising, then falling, and finally stabilizing, with their concentrations ranging from 88.74 to 33349.08 mg / m 3 10.54~2403.52mg / m 3 and 29.00~2099.20mg / m 3During the experiment, the emission requirements of the "Landfill Pollution Control Standard" (GB 16889-2008) and the "Odor Pollutant Emission Standard" (GB 14554-93) were exceeded. However, in the experimental group with the in-situ biological window treatment device, the gas pollutants existed for a shorter time. During the whole experiment, the concentrations of H2S, CH3SH and C7H8 were 0.01-0.05 mg / m 3 0.001~0.004mg / m 3 0.072~0.094mg / m 3 , meeting the emission requirements of the "Pollution Control Standard for Municipal Waste Landfills" (GB 16889-2008) and the "Emission Standard for Odor Pollutants" (GB 14554-93).

[0056] Example 3

[0057] In this embodiment, the combined landfill gas pollutant in-situ biological window treatment device of Example 1 is used in the laboratory to use CH4, H2S, CH3SH, C7H8 and other standard gases to be configured into a certain concentration, and then the removal performance of the device for gaseous pollutants is evaluated under the condition of simulating continuous flow into the device.

[0058] In this embodiment, the concentrations of CH4, H2S, CH3SH, and C7H8 in the inlet gas are 50%, 714286 mg / m 3 , 2000mg / m 3 and 2000mg / m 3 , gas flow rate is 18.75L / (m 2 h), the measurement results of gas emission concentration are as follows Figure 8 As shown:

[0059] During the whole experiment, the CH4 emission concentration was less than 0.08%, which can reach the 0.1% required by the "Pollution Control Standard for Municipal Waste Landfill" (GB 16889-2008). As the experiment progressed, only trace amounts of H2S, CH3SH and C7H8 were detected in the first two days, with average concentrations of 0.05, 0.006 and 0.08 mg / m 3 , Subsequently, H2S, CH3SH and C7H8 could not be measured, i.e., they were below the detection limit, which indicated that the device could effectively remove landfill gas pollutants and meet the emission requirements of the “Pollution Control Standard for Municipal Waste Landfills” (GB 16889-2008) and the “Emission Standard for Odor Pollutants” (GB 14554-93).

[0060] The embodiments described above provide a detailed description of the technical solutions of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements or similar substitutions made within the scope of the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A combined landfill gas pollutant in-situ biological window treatment device, characterized in that: The device comprises a window top (1), at least two processing boxes, a base (5) and an equipment box (6), wherein the window top (1), the processing box and the base (5) are arranged from top to bottom, and the window top (1) and the processing box, the processing boxes and the processing box and the base (5) are connected in a detachable manner and gases can be exchanged; The processing boxes are all open-top boxes, the peripheral walls of the boxes are sealing plates, and the bottom walls are perforated plates (9). Lightweight inert fillers (12) and main body fillers (13) are filled in the processing boxes, the lightweight inert fillers (12) are located at the bottom layer, and the main body fillers (13) are located at the upper layer; the processing box connected to the window top (1) is provided with a water distribution device to maintain the humidity of the fillers, and the remaining processing boxes are provided with water distribution devices and gas injection devices to maintain the humidity of the fillers and regulate the oxygen concentration; The base (5) is a box with an open top, the peripheral wall of the box is a sealing plate, the bottom wall is a punching plate (9), and a light inert filler (12) is filled in the base; The equipment box (6) is equipped with a water pump (15), a blower (16), a battery (17) and a water collection bucket (31). The battery (17) supplies energy to the equipment, the water collection bucket (31) and the water pump (15) provide water for the water distribution device, and the blower (16) provides air for the gas injection device. The water pump (15) and the blower (16) are started and stopped by a time-controlled switch (21).

2. The combined landfill gas pollutant in-situ biological window treatment device according to claim 1 is characterized in that: The window top (1) adopts an inclined top, a bayonet U-shaped groove is arranged at the bottom of the window top (1), a plug plate is arranged at the top of each processing box, a bayonet U-shaped groove is arranged at the bottom, and a plug plate is arranged at the top of the base (5), and the window top (1) and the processing box, the processing boxes, and the processing box and the base (5) are all connected through the cooperation of the bayonet U-shaped groove and the plug plate.

3. The combined landfill gas pollutant in-situ biological window treatment device according to claim 1 is characterized in that: The processing box comprises a top processing box (2), a middle processing box (3) and a bottom processing box (4), and the window top (1), the top processing box (2), the middle processing box (3), the bottom processing box (4) and the base (5) are arranged from top to bottom; the depth of the processing box is 50 to 80 cm, the length and width are both 1 to 5 m, and the aperture of the punching plate (9) is 5 to 10 mm.

4. The combined landfill gas pollutant in-situ biological window treatment device according to claim 1 is characterized in that: A water distribution device is arranged on the top of the peripheral wall of the treatment box connected to the top of the window (1), and the water distribution device comprises a water distribution branch pipe (7) and a sprinkler head (8); the bottom wall of the treatment box connected to the top of the window (1) serves as the top wall of the next treatment box, and a water distribution device is arranged on the inner top wall of the next treatment box, and the water distribution device comprises a water distribution branch pipe (7) and a sprinkler head (8); an air injection device is arranged on the inner bottom wall, and the air injection device comprises an air injection branch pipe (10), and a hole is opened on the air injection branch pipe (10); the subsequent treatment boxes are arranged in the same manner, and the outer bottom wall of the last treatment box is not provided with a water distribution device.

5. The combined landfill gas pollutant in-situ biological window treatment device according to claim 4 is characterized in that: The water distribution branch pipe (7) is connected to the water distribution main pipe (18) through an electronic control valve (20), and the water distribution main pipe (18) is directly connected to the water pump (15). The water distribution main pipe (18) and the water distribution branch pipe (7) are made of polyethylene PVC pipes to maintain the humidity of the filler at 30% to 50%; the gas injection branch pipe (10) is connected to the gas injection main pipe (19) through an electronic control valve (20), and the gas injection main pipe (19) is directly connected to the blower (16). The gas injection main pipe (19) and the gas injection branch pipe (10) are made of polyethylene PVC pipes to adjust the oxygen concentration in the treatment box to be greater than 3%.

6. The combined landfill gas pollutant in-situ biological window treatment device according to claim 1 is characterized in that: The light inert filler (12) is a polyurethane sponge or a Raschig ring filler, and the main filler (13) is a mixed filler of stabilized garbage bio-soil, biochar and garbage incineration slag, wherein the stabilized garbage bio-soil accounts for 90% to 98%, the pH value of the mixed filler is 6.5 to 8.5, and the particle size is ≤6 mm.

7. The combined landfill gas pollutant in-situ biological window treatment device according to claim 1 is characterized in that: The processing box is filled with a light inert filler (12) with a height of 1 to 3 cm, and the rest is a main filler (13); the height of the light inert filler (12) filled in the base (5) is 20 to 40 cm.

8. A method for treating gas pollutants in a landfill, characterized in that: Use the combined landfill gas pollutant in-situ biological window treatment device described in any one of claims 1-7.

9. The method for treating landfill gas pollutants according to claim 8, characterized in that: The landfill cover structure covers the surface of the garbage layer (27), and includes a drainage layer (23), an impermeable layer (24), a sub-membrane protective layer (25) and a gas exhaust layer (26) from top to bottom; Aiming at the gas exhaust pipe (22) area where the release of gas pollutants in the landfill is high, the combined landfill gas pollutant in-situ biological window treatment device is arranged on the impermeable layer (24), with the gas exhaust pipe (22) as the center, the base (5) and the treatment box are provided with gas exhaust pipe (22) through-holes, and the peripheral wall of the treatment box connected to the window top (1) is provided with gas exhaust pipe (22) outlet holes; For the hot spot area of ​​gas pollutant release in a landfill that is not a gas exhaust pipe, the combined landfill gas pollutant in-situ biological window treatment device is arranged on the anti-seepage layer (24) or the exhaust layer (26) at the hot spot area of ​​gas pollutant release.

10. The method for treating landfill gas pollutants according to claim 8, characterized in that: When the combined landfill gas pollutant in-situ biological window treatment device is applied to a covering layer structure, the combined landfill gas pollutant in-situ biological window treatment device is surrounded by an anti-seepage layer (24), a low-permeability soil layer (28) and a vegetation layer (29) to guide the gas pollutants through the device.

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