Aerobic biological enhanced degradation and percolate circulating recharge co-treatment process

Abstract

The invention relates to the technical field of refuse landfills, and discloses an aerobic biological enhanced degradation and percolate cyclic recharge co-treatment process, which comprises the steps of complex microbial inoculant screening, microbial metabolism regulation and control, microbial metabolism environment optimization, microbial inoculant staged addition, dynamic recharge proportion regulation and control, percolate pretreatment and landfill gas resource utilization. Through the treatment process, the aerobic biological enhanced degradation effect of the landfill can be improved, and the yield of the leachate is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of landfills, and in particular relates to a collaborative treatment process of aerobic bio-enhanced degradation and leachate recycling and re-injection. Background Art

[0002] Currently, in the landfill treatment process, existing technologies mainly focus on separate aerobic biological treatment and leachate reinjection technology, but there are generally problems such as high energy consumption, ammonia nitrogen accumulation, and lack of synergy.

[0003] Existing aerobic biological treatment technology and its shortcomings 1. Traditional aerobic processes: such as the activated sludge process, oxidation ditch, and biological rotary disc, promote the degradation of organic matter by microorganisms through aeration, and the COD removal rate can reach over 90%. However, continuous oxygen supply is required and energy consumption is high.

[0004] Quasi-aerobic landfill technology: accelerates garbage degradation through natural ventilation or artificial gas injection.

[0005] Main flaws: High energy consumption: Traditional aerobic processes rely on mechanical aeration or gas injection equipment, and small landfills find it difficult to afford the operating costs.

[0006] Low ammonia nitrogen removal efficiency: Although aerobic treatment can degrade COD, ammonia nitrogen is easily accumulated, requiring additional denitrification processes such as stripping or chemical precipitation, which increases complexity.

[0007] Poor environmental adaptability: Under low temperature or high load conditions, microbial activity decreases and treatment efficiency is significantly reduced.

[0008] Existing leachate reinjection technology and its defects: 1. Simple recharge technology: The leachate is sprayed back into the landfill layer, and the pollutants are degraded by microorganisms in the garbage layer.

[0009] Water balance optimization: Reduce the total amount of leachate by adjusting the recharge frequency and load.

[0010] Main flaws: Ammonia nitrogen accumulation: Long-term reinjection of untreated leachate will lead to increased NH3-N concentration, requiring additional denitrification measures.

[0011] Inhibition of microbial activity: High concentrations of pollutants, such as heavy metals Zn²⁺ and Cu²⁺, or extreme pH values ​​(<6.5 or >7.5) can inhibit microbial activity and reduce degradation efficiency.

[0012] Insufficient dynamic regulation: Traditional recharge relies on fixed frequency or load and cannot adjust the strategy according to real-time water quality, which can easily cause short-flow or local blockage.

[0013] Therefore, we proposed a coordinated treatment process of aerobic bio-enhanced degradation and leachate recycling and re-injection. Summary of the Invention

[0014] The purpose of the present invention is to improve the aerobic bio-enhanced degradation effect of landfills and reduce the leachate production, and to provide a collaborative treatment process of aerobic bio-enhanced degradation and leachate recycling and recharge.

[0015] The technical solution adopted in the present invention is as follows: Aerobic bio-enhanced degradation and leachate recycling and reinjection synergistic treatment process, the synergistic treatment process is: S1: Screening of composite bacterial agents. Targeting the landfill environment, we screened high-temperature- and high-salt-tolerant heterotrophic nitrification-aerobic denitrification strains, and combined them with phosphate-accumulating bacteria and cellulose-degrading bacteria to form composite bacterial agents. S2: Microbial metabolic regulation: The bacterial agent absorbs heavy metals by secreting extracellular polymers. Combined with the dilution effect of leachate recirculation, the concentration of heavy metal leaching is reduced. At the same time, the bacterial community promotes humic acid production through the Maillard reaction and polyphenol humification pathway, improving the stability of landfill waste. S3: Optimize the microbial metabolism environment by pre-buried air injection wells and liquid injection wells in the landfill. High-pressure fans are used to inject fresh air into the deep layer of garbage to maintain an oxygen concentration of ≥5%. At the same time, waste gases such as CO2 are extracted to facilitate microbial metabolism. S4: Bacterial agents are added in stages. In the initial stage, highly active bacteria are added to accelerate the decomposition of organic matter, and denitrifying bacteria are added in the later stage to enhance the removal of ammonia nitrogen. S5: Dynamic recharge ratio control, using integrated IoT sensors and a PLC control station to monitor COD, NH3-N, pH, Zn²⁺, and Cu²⁺ parameters in the landfill leachate in real time. The recharge ratio is calculated using a recharge formula to prevent high ammonia nitrogen from inhibiting microbial activity. S6: Leachate pretreatment: If the leachate COD>10000 mg / L or BOD>5000 mg / L, chemical oxidation pretreatment is performed to reduce COD≤1000 mg / L and BOD≤500 mg / L; if the pH exceeds the range of 6.5-7.5, acid-base neutralization is used for adjustment; S7: Landfill gas resource utilization. Under aerobic conditions, landfill gas is used for power generation after desulfurization treatment. The high-temperature flue gas generated by incineration power generation is used for multi-effect evaporation of leachate, and the low-temperature waste heat is used to preheat the aeration air.

[0016] In a preferred embodiment of the invention, the reinjection formula is: (R = (100 - \frac{C_{NH_4-N}}{20})\% \) .

[0017] In a preferred embodiment of the invention, when the integrated Internet of Things sensor detects that COD, NH3-N, pH, Zn²⁺ or Cu²⁺ reaches a threshold value, it triggers a chemical precipitation device to remove heavy metals and then re-inject them.

[0018] In a preferred embodiment of the invention, the dynamic recharge will control the recharge intensity in different regions according to the garbage pile to avoid short-circuiting or local blockage, reduce the recharge amount in high water content areas, and increase the recharge frequency in low water content areas.

[0019] In a preferred embodiment of the invention, the ventilation equipment, monitoring equipment, and leachate treatment unit in the collaborative treatment process are integrated into a standard container for quick deployment and installation.

[0020] In a preferred embodiment of the invention, the landfill simultaneously pre-buries a drainage layer during the excavation stage and inoculates denitrifying bacteria.

[0021] In a preferred embodiment of the invention, the integrated IoT sensor includes a COD sensor, a pH sensor, and a metal ion sensor, and integrates wireless modules such as 5G and LoRa to feed back sensor data to the PLC control station for monitoring and early warning.

[0022] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. In the present invention, a combination of high-temperature-resistant and high-salt bacterial strains is used to improve the organic matter degradation rate. At the same time, the heavy metal leaching concentration is reduced through extracellular polymer adsorption, and humic acid production is promoted through the Maillard reaction. The settling rate of the garbage pile is increased, the stabilization period is shortened, humification enhances stability, and microbial metabolism is optimized, thereby improving the aerobic bio-enhanced degradation effect of the landfill.

[0023] In the present invention, integrated Internet of Things sensors are used in conjunction with AI algorithms to optimize recharge parameters in real time, and a regional recharge strategy is used to improve the uniformity of leachate distribution, dynamically adjust the recharge volume and frequency, avoid short-flow or blockage, reduce the peak values ​​of organic matter and ammonia nitrogen, and reduce leachate production.

[0024] In the present invention, the deep coupling of bio-augmentation and intelligent recharge is utilized to break through the problem of traditional process separation, realize the integration of degradation, denitrification and resource utilization, reduce operation and maintenance costs, and is suitable for the treatment of old landfills, the anti-seepage transformation of new sites and high-altitude cold areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a flow chart of the collaborative processing process of the present invention. DETAILED DESCRIPTION

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0027] The following will be combined Figure 1 The aerobic bio-enhanced degradation and leachate recycling and reinjection synergistic treatment process according to the embodiment of the present invention is described in detail.

[0028] Example 1: Reference Figure 1 , aerobic bio-enhanced degradation and leachate recycling and reinjection coordinated treatment process, the coordinated treatment process is: composite bacterial agent screening, according to the landfill environment, screen high temperature and high salt resistant heterotrophic nitrification-aerobic denitrification strains, combined with polyphosphate bacteria, cellulose degrading bacteria and other components to form a composite bacterial agent; microbial metabolic regulation, the bacterial agent absorbs heavy metals by secreting extracellular polymers, combined with the dilution effect of leachate recycling and reinjection, so as to reduce the concentration of heavy metal leaching. At the same time, the bacterial community promotes the production of humic acid through the Maillard reaction and polyphenol humification pathway, thereby improving the stability of landfill garbage; optimize the microbial metabolic environment, pre-buried gas injection wells and liquid injection wells in the landfill, and injects fresh air into the deep layer of garbage through high-pressure fans to maintain an oxygen concentration of ≥5% , while exhausting CO2 and other waste gases to facilitate microbial metabolism; bacterial agents are added in stages, with highly active bacteria added in the initial stage to accelerate the decomposition of organic matter, and denitrifying bacteria are added in the later stage to enhance the removal of ammonia nitrogen; during dynamic recharge, the recharge intensity will be controlled in different areas according to the garbage pile to avoid short-flow or local blockage, the recharge volume will be reduced in high-water-content areas, and the recharge frequency will be increased in low-water-content areas; specifically, a combination of high-temperature resistant and high-salt bacterial strains is used to increase the degradation rate of organic matter, while the leaching concentration of heavy metals is reduced through extracellular polymer adsorption, and the production of humic acid is promoted through the Maillard reaction, the sedimentation rate of the garbage pile is increased, the stabilization period is shortened, humification enhances stability, and microbial metabolism is optimized, thereby improving the aerobic bio-enhanced degradation effect of the landfill.

[0029] Example 2: Reference Figure 1, dynamic recharge ratio control, using integrated IoT sensors and PLC control stations to monitor the parameters of COD, NH3-N, pH, Zn²⁺, and Cu²⁺ in the leachate water quality of the landfill in real time, and calculate the recharge ratio through the recharge formula to avoid high ammonia nitrogen inhibiting microbial activity; the recharge formula is: ( R = (100 - \frac{C_{NH_4-N}}{20})\% \); when the integrated IoT sensor detects that COD, NH3-N, pH, Zn²⁺ or Cu²⁺ reaches the threshold, it will trigger the chemical precipitation device to remove heavy metals and then recharge; leachate pretreatment, if the leachate COD>10000 mg / L or BOD>5000 mg / L, chemical oxidation pretreatment is performed to COD≤1000 mg / L and BOD≤500 mg / L; when the pH exceeds the range of 6.5-7.5, acid-base neutralization adjustment is adopted; landfill gas is utilized as a resource, and landfill gas is used for power generation after desulfurization under aerobic conditions. The high-temperature flue gas generated by incineration power generation is used for multi-effect evaporation of leachate, and the low-temperature waste heat is used to preheat the aeration air; specifically, the integrated Internet of Things sensor is used with the AI ​​algorithm to optimize the recharge parameters in real time, and cooperate with the regional recharge strategy to improve the uniformity of leachate distribution, dynamically adjust the recharge volume and frequency, avoid short flow or blockage, reduce the peak value of organic matter and ammonia nitrogen, and reduce the leachate production.

[0030] Reference Figure 1 In the collaborative treatment process, ventilation equipment, monitoring equipment, and leachate treatment units are integrated into standard containers for rapid deployment and installation; the landfill simultaneously pre-buries the drainage layer during the excavation stage and inoculates denitrifying bacteria; the integrated Internet of Things sensors include COD sensors, pH sensors, and metal ion sensors, and integrate 5G, LoRa and other wireless modules to feed back sensor data to the PLC control station for monitoring and early warning; this application utilizes the deep coupling of bio-augmentation and intelligent recharge to break through the problem of traditional process separation, realize the integration of degradation, denitrification, and resource utilization, reduce operation and maintenance costs, and is suitable for the management of old landfills, anti-seepage transformation of new sites, and high-altitude cold areas.

[0031] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0032] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. The synergistic treatment process of aerobic bio-enhanced degradation and leachate recycling and re-injection is characterized by: The collaborative processing process is: S1: Screening of composite bacterial agents. Targeting the landfill environment, we screened high-temperature- and high-salt-tolerant heterotrophic nitrification-aerobic denitrification strains, and combined them with phosphate-accumulating bacteria and cellulose-degrading bacteria to form composite bacterial agents. S2: Microbial metabolic regulation: The bacterial agent absorbs heavy metals by secreting extracellular polymers. Combined with the dilution effect of leachate recirculation, the concentration of heavy metal leaching is reduced. At the same time, the bacterial community promotes humic acid production through the Maillard reaction and polyphenol humification pathway, improving the stability of landfill waste. S3: Optimize the microbial metabolism environment by pre-buried gas injection wells and liquid injection wells in the landfill. High-pressure fans are used to inject fresh air into the deep layer of garbage to maintain an oxygen concentration of ≥5%. At the same time, waste gases such as CO2 are extracted to facilitate microbial metabolism. S4: Bacterial agents are added in stages. In the initial stage, highly active bacteria are added to accelerate the decomposition of organic matter, and denitrifying bacteria are added in the later stage to enhance the removal of ammonia nitrogen. S5: Dynamic recharge ratio control, using integrated IoT sensors and PLC control stations to monitor the COD, NH3-N, pH, The parameters are used to calculate the recharge ratio through the recharge formula to avoid high ammonia nitrogen inhibiting microbial activity; S6: Leachate pretreatment: if the leachate COD>10000mg / L or BOD>5000mg / L, chemical oxidation pretreatment is performed to COD≤1000mg / L and BOD≤500mg / L; When the pH exceeds the range of 6.5-7.5, acid-base neutralization should be used for adjustment; S7: Landfill gas resource utilization. Under aerobic conditions, landfill gas is used for power generation after desulfurization treatment. The high-temperature flue gas generated by incineration power generation is used for multi-effect evaporation of leachate, and the low-temperature waste heat is used to preheat the aeration air.

2. The aerobic bio-enhanced degradation and leachate recycling and re-injection synergistic treatment process according to claim 1, characterized in that: The recharge formula is: (R = (100-\frac{C_{NH_4-N}}{20})\%\).

3. The aerobic bio-enhanced degradation and leachate recycling and re-injection synergistic treatment process according to claim 1, characterized in that: The integrated IoT sensor monitors COD, NH3-N, pH, or When the threshold is reached, the chemical precipitation device will be triggered to remove heavy metals and then re-inject.

4. The aerobic bio-enhanced degradation and leachate recycling and re-injection synergistic treatment process according to claim 1, characterized in that: During the dynamic recharge, the recharge intensity will be controlled in different areas according to the garbage pile to avoid short-flow or local blockage. The recharge amount will be reduced in high-water-content areas, and the recharge frequency will be increased in low-water-content areas.

5. The aerobic bio-enhanced degradation and leachate recycling and re-injection synergistic treatment process according to claim 1, characterized in that: The ventilation equipment, monitoring equipment, and leachate treatment unit in the collaborative treatment process are integrated into a standard container for quick deployment and installation.

6. The aerobic bio-enhanced degradation and leachate recycling and re-injection synergistic treatment process according to claim 1, characterized in that: The landfill simultaneously pre-buries a drainage layer during the excavation stage and inoculates denitrification bacteria.

7. The aerobic bio-enhanced degradation and leachate recycling and re-injection synergistic treatment process according to claim 1, characterized in that: The integrated IoT sensor includes a COD sensor, a pH sensor, and a metal ion sensor, and integrates wireless modules such as 5G and LoRa to feed back sensor data to the PLC control station for monitoring and early warning.

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