Ecological restoration seepage liquid for refuse landfill and preparation method of ecological restoration seepage liquid

Abstract

The invention discloses a refuse landfill ecological restoration seepage and a preparation method thereof, the refuse landfill ecological restoration seepage comprises the following components: an organic component, an inorganic component, a microbial agent, a chemical component, a dispersant and a stabilizer, the organic component is humic acid or organic acid; the inorganic component is mineral powder; the microbial agent is a compound probiotic group; the chemical component is an oxidizing / reducing agent, the humic acid is any one of soil humic acid, coal humic acid, regenerated humic acid, fulvic acid, ulmic acid or humic acid, the organic acid is low-molecular organic acid, and the low-molecular organic acid is any one of citric acid, oxalic acid or succinic acid; the ecological restoration seepage liquid for the refuse landfill and the preparation method can efficiently decompose heavy metals such as cadmium and lead and pollutants such as petroleum hydrocarbon and polycyclic aromatic hydrocarbon, can promote biodegradation of organic pollutants and enhance the ecological function of soil, and is suitable for popularization and application.

Description

Technical Field

[0001] The invention relates to the technical field of soil ecological restoration, and in particular to a landfill ecological restoration leachate and a preparation method thereof. Background Art

[0002] Data provided by the China Association of Urban Environmental Sanitation show that the current per capita domestic waste production in my country is about 440 kilograms, and the annual urban waste production in the country reaches 180 million tons, and it is growing at a rate of 8%-10% per year. At present, the use of landfills in my country has entered a peak period, and many problems have also been exposed. The construction and use of landfills not only occupy a large amount of land resources, but also are huge potential comprehensive pollution sources in cities. The landfill gas and other odorous gases produced by them not only affect the daily lives of surrounding residents, but also breed mosquitoes and spread diseases, seriously affecting the environment and ecology.

[0003] In order to improve the landfill itself and its surrounding environment, vegetation is usually planted around it, which not only beautifies the environment but also absorbs harmful substances in the site.

[0004] However, landfilling will cause soil pollution. These pollution sources are usually pollutants such as heavy metals, petroleum hydrocarbons, polycyclic aromatic hydrocarbons, and abnormal bacterial colonies. When vegetation is planted, it is difficult for it to survive or grow for a long time. Therefore, there is an urgent need for a leachate that can repair the landfill soil so that the soil can meet the needs of vegetation growth. Summary of the invention

[0005] The purpose of the present invention is to solve the above-mentioned problems and provide a landfill ecological restoration leachate and a preparation method thereof which can efficiently decompose heavy metals such as cadmium and lead and pollutants such as petroleum hydrocarbons and polycyclic aromatic hydrocarbons, and can also promote the biodegradation of organic pollutants and enhance the ecological function of the soil.

[0006] To achieve the above-mentioned purpose, the technical solution of the present invention is: a landfill ecological restoration leachate, comprising the following components: organic components, inorganic components, microbial agents, chemical components, dispersants and stabilizers, wherein the organic components are humic acid or organic acid; the inorganic components are mineral powders; the microbial agents are composite probiotics; and the chemical components are oxidizing / reducing agents.

[0007] Preferably, the humic acid is any one of soil humic acid, coal-based humic acid, regenerated humic acid, fulvic acid, palmitic acid or black humic acid.

[0008] Preferably, the organic acid is a low molecular weight organic acid, and the low molecular weight organic acid is any one of citric acid, oxalic acid or succinic acid.

[0009] Preferably, the mineral powder in the inorganic component is any one or more combinations of calcium powder, active magnesium oxide powder, silicon powder, iron powder, electrolytic manganese powder and zinc powder.

[0010] Preferably, the microbial agent is a mixture of actinomycetes and Bacillus, and the concentration of the actinomycetes is (3-5) x10 6 CFU / g, the concentration of Bacillus is (5-9)x10 6 CFU / g; the ratio of actinomycetes to Bacillus is 1:2-3.

[0011] Preferably, the oxidizing / reducing agent in the chemical composition is sulfate or zero-valent iron, wherein the sulfate is any one of persulfate, sodium persulfate or potassium persulfate, and the zero-valent iron is any one of nano zero-valent iron, coated nano zero-valent iron or loaded zero-valent iron.

[0012] Preferably, it also includes auxiliary components, which are adhesives or structure improvers.

[0013] A method for preparing leachate for ecological restoration of landfills, comprising the following steps: S1: preparing active ingredients; S2: obtaining a basic formula, wherein the basic formula comprises a sodium persulfate solution, a dispersant and a stabilizer; S3: mixing the active ingredients with the basic formula according to mass percentage.

[0014] Preferably, the step S1 specifically comprises the following steps: S101: preparing a nano zero-valent iron suspension; mixing a ferric salt or ferrous salt solution with freeze-dried yeast, stirring for adsorption, and then centrifuging and washing to obtain a Fe-loaded suspension. 2+ / Fe 3+ yeast; then, under the protection of nitrogen, the yeast loaded with metal ions is added dropwise to the sodium borohydride solution with stirring, and then filtered and washed to obtain the nano zero-valent iron active ingredient; at the same time, the nano zero-valent iron is coated with an organic polymer to form a stable suspension to prevent agglomeration and improve mobility; S102: humic acid liquid extraction; weathered coal or lignite is used as raw material, and nitrohumic acid is produced by nitric acid oxidation treatment, which is dissolved in water and filtered to obtain an active humic acid solution; S103: preparation of microbial bacterial liquid, the Bacillus HP-3 strain is cultured in a nutrient solution, centrifuged and concentrated, and then mixed with a protective agent to obtain a high-concentration bacterial suspension.

[0015] Preferably, the steps of mixing the active ingredient with the basic formula in step S3 are as follows: S301: Take 30-35% of the coated nano zero-valent iron suspension, 20-25% of the humic acid solution, 10% of the inorganic component, 10% of the sodium persulfate solution, 5-10% of the microbial liquid, 2% of the dispersant and 5% of the stabilizer and mineral clay by mass percentage; S302: Slowly mix the coated nano zero-valent iron suspension and the humic acid solution under stirring conditions to avoid oxidation; S303: Add sodium persulfate solution, inorganic component, microbial liquid, dispersant and mineral clay in sequence, maintain pH 6-7, and stir for 30 minutes until uniform; S304: Finally, add the stabilizer, stir to form a homogeneous liquid, and store in a dark place after filling.

[0016] The invention discloses a landfill ecological restoration leachate and a preparation method thereof, comprising the following components: an organic component, an inorganic component, a microbial agent, a chemical component, a dispersant and a stabilizer, wherein the organic component is humic acid or an organic acid; the inorganic component is a mineral powder; the microbial agent is a composite probiotic bacteria group; the chemical component is an oxidizing / reducing agent, the humic acid is any one of soil humic acid, coal-based humic acid, regenerated humic acid, fulvic acid, palmitic acid or black humic acid, and the organic acid is a low-molecular organic acid, which is any one of citric acid, oxalic acid or succinic acid. Compared with the prior art, the landfill ecological restoration leachate and the preparation method thereof have the advantages of being able to efficiently decompose heavy metals such as cadmium and lead and pollutants such as petroleum hydrocarbons and polycyclic aromatic hydrocarbons, and can also promote the biodegradation of organic pollutants, while enhancing the beneficial effects of soil ecological functions. DETAILED DESCRIPTION

[0017] A landfill ecological restoration leachate comprises the following components: an organic component, an inorganic component, a microbial agent, a chemical component, a dispersant and a stabilizer, wherein the organic component is humic acid or organic acid; the inorganic component is mineral powder; the microbial agent is a composite probiotic group; and the chemical component is an oxidizing / reducing agent.

[0018] The humic acid is any one of soil humic acid, coal-derived humic acid, regenerated humic acid, fulvic acid, palmitic acid or black humic acid; the organic acid is a low-molecular organic acid, and the low-molecular organic acid is any one of citric acid, oxalic acid or succinic acid.

[0019] In this embodiment, soil humic acid, coal-based humic acid, regenerated humic acid, fulvic acid, palmitic acid or humic acid can all enhance the soil's ability to retain water and fertilizer, promote microbial activity, and improve soil group structure; among them, soil humic acid and regenerated humic acid are derived from the decomposition of animal and plant remains and are difficult to prepare, so coal-based humic acid is preferred in this embodiment.

[0020] In this embodiment, the mineral powder in the inorganic component is any one or more combinations of calcium powder, active magnesium oxide powder, silicon powder, iron powder, electrolytic manganese powder, and zinc powder. Among them, inorganic components such as calcium powder, active magnesium oxide powder, and silicon powder can adjust the pH value and mechanical strength of the soil, while trace elements such as iron powder, electrolytic manganese powder, and zinc powder can enhance plant resistance.

[0021] In addition, inorganic components also include heavy metal passivators, which can be phosphates, silicates, etc., which are used to fix heavy metal ions such as copper, mercury, and zinc in the soil, thereby increasing their mobility and biological effectiveness.

[0022] In this embodiment, the microbial agent is a mixture of actinomycetes and Bacillus, and the concentration of the actinomycetes is (3-5) x10 6 CFU / g, the concentration of Bacillus is (5-9)x10 6 CFU / g; the ratio of actinomycetes to bacillus is 1:2-3; the microbial agent can decompose organic pollutants, especially petroleum hydrocarbons and polycyclic aromatic hydrocarbons; at the same time, it can also inhibit the reproduction of harmful bacteria and restore the ecological balance of the soil.

[0023] In this embodiment, the oxidizing / reducing agent in the chemical composition is sulfate or zero-valent iron, wherein the sulfate is any one of persulfate, sodium persulfate or potassium persulfate, and the zero-valent iron is any one of nano zero-valent iron, coated nano zero-valent iron or loaded zero-valent iron; the chemical composition is used to degrade difficult-to-degrade organic matter, such as chlorinated hydrocarbon pollutants.

[0024] In addition, this embodiment also includes auxiliary components, which are adhesives or structural modifiers, and can be used to improve soil permeability and compaction problems.

[0025] Embodiment 1: A landfill ecological restoration leachate, comprising coal-based humic acid, calcium powder, active magnesium oxide, iron powder, zinc powder, sodium persulfate solution, microbial agent, coated nano zero-valent iron suspension, dispersant, stabilizer and auxiliary components; in terms of mass percentage, coal-based humic acid accounts for 20%, inorganic components (calcium powder, active magnesium oxide, iron powder, zinc powder) account for 10%, sodium persulfate solution accounts for 10%, microbial agent accounts for 5%, coated nano zero-valent iron suspension accounts for 30%, stabilizer accounts for 5%, dispersant accounts for 2%, and the balance is auxiliary component mineral clay.

[0026] The landfill ecological restoration leachate prepared in this embodiment can effectively remove lead and cadmium in the soil under the landfill, and has a high degradation rate for organic matter, which is beneficial to adjust the pH, shorten the soil restoration cycle, and make the restored soil meet the survival and growth of vegetation.

[0027] Embodiment 2: A landfill ecological restoration leachate, comprising coal-based humic acid, calcium powder, active magnesium oxide, iron powder, zinc powder, sodium persulfate solution, microbial agent, coated nano zero-valent iron suspension, dispersant, stabilizer and auxiliary components; in terms of mass percentage, coal-based humic acid accounts for 25%, inorganic components (calcium powder, active magnesium oxide, iron powder, zinc powder) account for 10%, sodium persulfate solution accounts for 10%, microbial agent accounts for 10%, coated nano zero-valent iron suspension accounts for 35%, stabilizer accounts for 5%, dispersant accounts for 2%, and the balance is auxiliary component mineral clay.

[0028] Embodiment 3: A landfill ecological restoration leachate, comprising coal-based humic acid, calcium powder, active magnesium oxide, iron powder, zinc powder, sodium persulfate solution, microbial agent, coated nano zero-valent iron suspension, dispersant, stabilizer and auxiliary components; in terms of mass percentage, coal-based humic acid accounts for 23%, inorganic components (calcium powder, active magnesium oxide, iron powder, zinc powder) account for 10%, sodium persulfate solution accounts for 10%, microbial agent accounts for 8%, coated nano zero-valent iron suspension accounts for 33%, stabilizer accounts for 5%, dispersant accounts for 2%, and the balance is auxiliary component mineral clay.

[0029] The method for preparing the landfill ecological restoration leachate comprises the following steps: S1: preparing active ingredients; S2: obtaining a basic formula, wherein the basic formula comprises a sodium persulfate solution, a dispersant and a stabilizer; S3: mixing the active ingredients with the basic formula according to mass percentage.

[0030] Preferably, the step S1 specifically comprises the following steps: S101: preparing a nano zero-valent iron suspension; mixing a ferric salt or ferrous salt solution with freeze-dried yeast, stirring for adsorption, and then centrifuging and washing to obtain a Fe-loaded suspension. 2+ / Fe 3+ yeast; then, under the protection of nitrogen, the yeast loaded with metal ions is added dropwise to the sodium borohydride solution and stirred, and then filtered and washed to obtain the nano zero-valent iron active ingredient; at the same time, the nano zero-valent iron is coated with an organic polymer (polyaspartic acid) to form a stable suspension to prevent agglomeration and improve mobility; S102: humic acid liquid extraction; weathered coal or lignite is used as raw material, and nitrohumic acid is produced by nitric acid oxidation treatment, which is dissolved in water and filtered to obtain an active humic acid solution; S103: microbial bacterial liquid preparation, the Bacillus HP-3 strain is expanded in a nutrient solution, centrifuged and concentrated, and then mixed with a protective agent (such as glycerol) to obtain a high-concentration bacterial suspension.

[0031] Preferably, the steps of mixing the active ingredient with the basic formula in step S3 are as follows: S301: Take 30-35% of the coated nano zero-valent iron suspension, 20-25% of the humic acid solution, 10% of the inorganic component, 10% of the sodium persulfate solution, 5-10% of the microbial liquid, 2% of the dispersant and 5% of the stabilizer and mineral clay by mass percentage; S302: Slowly mix the coated nano zero-valent iron suspension and the humic acid solution under stirring conditions to avoid oxidation; S303: Add sodium persulfate solution, inorganic component, microbial liquid, dispersant and mineral clay in sequence, maintain pH 6-7, and stir for 30 minutes until uniform; S304: Finally, add the stabilizer, stir to form a homogeneous liquid, and store in a dark place after filling.

[0032] Degradation of organic pollutants: Sodium persulfate solution and nano-zero-valent iron synergistically produce active free radicals SO4 - , -OH, and efficiently decompose pollutants such as petroleum hydrocarbons and polycyclic aromatic hydrocarbons; coal-based humic acid fixes heavy metals such as cadmium and lead through chelation, while the coated nano zero-valent iron suspension reduces hexavalent chromium to low-toxic trivalent chromium; in addition, through microbial synergistic remediation, the bacterial liquid promotes the biodegradation of organic pollutants and enhances the ecological function of the soil.

[0033] The landfill ecological restoration seepage liquid prepared by the above preparation method is sprayed onto the surface soil of the landfill through an atomizing pump when in use, once every two days, so that the restoration liquid seepage liquid gradually penetrates into the soil, thereby improving the restoration effect.

[0034] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A landfill ecological restoration leachate, characterized in that: The invention comprises the following components: organic components, inorganic components, microbial agents, chemical components, dispersants and stabilizers, wherein the organic components are humic acid or organic acid; the inorganic components are mineral powder; the microbial agents are composite probiotics; and the chemical components are oxidizing / reducing agents.

2. The landfill ecological restoration leachate according to claim 1, characterized in that: The humic acid is any one of soil humic acid, coal-derived humic acid, regenerated humic acid, fulvic acid, palmitic acid or black humic acid.

3. The landfill ecological restoration leachate according to claim 1, characterized in that: The organic acid is a low molecular weight organic acid, and the low molecular weight organic acid is any one of citric acid, oxalic acid or succinic acid.

4. The landfill ecological restoration leachate according to claim 1, characterized in that: The mineral powder in the inorganic component is any one or more combinations of calcium powder, active magnesium oxide powder, silicon powder, iron powder, electrolytic manganese powder and zinc powder.

5. The landfill ecological restoration leachate according to claim 1, characterized in that: The microbial agent is a mixture of actinomycetes and bacillus, and the concentration of the actinomycetes is (3-5) x10 6 CFU / g, the concentration of Bacillus is (5-9)x10 6 CFU / g; the ratio of actinomycetes to Bacillus is 1:2-3.

6. The landfill ecological restoration leachate according to claim 1, characterized in that: The oxidizing / reducing agent in the chemical composition is sulfate or zero-valent iron, wherein the sulfate is any one of persulfate, sodium persulfate or potassium persulfate, and the zero-valent iron is any one of nano zero-valent iron, coated nano zero-valent iron or loaded zero-valent iron.

7. The landfill ecological restoration leachate according to any one of claims 1 to 6, characterized in that: It also includes auxiliary components, which are adhesives or structure improvers.

8. A method for preparing landfill ecological restoration leachate, characterized in that: The method comprises the following steps: S1: preparation of active ingredients; S2: obtaining a basic formula, wherein the basic formula includes a sodium persulfate solution, a dispersant and a stabilizer; S3: mixing the active ingredient with the basic formula according to mass percentage.

9. The method for preparing landfill ecological restoration leachate according to claim 8, characterized in that: The step S1 specifically includes the following steps: S101: preparing nano zero-valent iron suspension; mixing the ferric salt or ferrous salt solution with freeze-dried yeast, stirring for adsorption, and then centrifuging and washing to obtain Fe-loaded 2+ / Fe 3+ yeast; then, under the protection of nitrogen, the yeast loaded with metal ions is added dropwise to the sodium borohydride solution with stirring, and then filtered and washed to obtain the nano zero-valent iron active ingredient; at the same time, the nano zero-valent iron is coated with an organic polymer to form a stable suspension to prevent agglomeration and improve mobility; S102: humic acid liquid extraction; weathered coal or lignite is used as raw material, and nitrohumic acid is produced by nitric acid oxidation treatment, which is dissolved in water and filtered to obtain an active humic acid solution; S103: preparation of microbial bacterial liquid, the Bacillus HP-3 strain is expanded in a nutrient solution, centrifuged and concentrated, and then mixed with a protective agent to obtain a high-concentration bacterial suspension.

10. The method for preparing landfill ecological restoration leachate according to claim 8, characterized in that: The steps of mixing the active ingredient with the basic formula in step S3 are as follows: S301: Take 30-35% of the coated nano zero-valent iron suspension, 20-25% of the humic acid solution, 10% of the inorganic component, 10% of the sodium persulfate solution, 5-10% of the microbial liquid, 2% of the dispersant and 5% of the stabilizer and mineral clay by mass percentage; S302: Slowly mix the coated nano zero-valent iron suspension and the humic acid solution under stirring conditions to avoid oxidation; S303: Add sodium persulfate solution, inorganic component, microbial liquid, dispersant and mineral clay in sequence, maintain pH 6-7, and stir for 30 minutes until uniform; S304: Finally, add the stabilizer, stir to form a homogeneous liquid, and store in a dark place after filling.