Pretreatment method for recovering phosphorus in sludge

Abstract

The invention discloses a pretreatment method for recycling phosphorus in sludge, which is characterized in that the sludge is subjected to reduction treatment by adopting aerobic biological decomposition drying, phosphorus is screened and fixed, and then phosphorus is recycled through pickling, the pretreatment method for recycling phosphorus in sludge is provided, the method is simple to operate, the cost is low, and the method is suitable for industrial production. The sludge is subjected to reduction treatment, resource recovery of phosphorus in the sludge is realized, and the problem of environmental pollution caused by loss of phosphorus in wastewater is prevented.

Description

Technical Field

[0001] This invention relates to a method for phosphorus recovery, specifically a pretreatment method for phosphorus recovery from sludge. Background Technology

[0002] Phosphorus is an indispensable and irreplaceable element for life on Earth, its importance self-evident. With population growth and continuous industrial development, the world's phosphate rock reserves are only sufficient for 50-100 years of use. Taking my country as an example, although its total phosphate rock reserves rank among the top three in the world, most of it is low-grade and difficult to mine. Therefore, phosphorus is listed as one of the twenty key minerals for exploration in my country. Phosphorus recovery is an important measure to alleviate the "phosphorus crisis."

[0003] Biological treatment Currently, the most common sludge treatment method used in wastewater treatment systems is biological sludge treatment, which primarily relies on microorganisms to remove phosphorus from the sludge. This method is mainly divided into two categories: anaerobic digestion and aerobic digestion. During anaerobic treatment, phosphorus is released into the digestate, achieving phosphorus release from the sludge, but the phosphorus concentration is low. Aerobic digestion typically uses composting, which results in a large amount of straw and other waste mixed in with the effluent, hindering phosphorus extraction.

[0004] Acid-base treatment Direct acid and alkali treatment of sludge, either directly or after drying, requires large quantities of acid and alkali, resulting in high costs and low phosphorus concentration in the liquid, which is not conducive to subsequent phosphorus recovery.

[0005] Therefore, researching a process for sludge treatment using aerobic decomposition and drying technology can achieve the concentration and enrichment of phosphorus in sludge, screen out the residue after sludge reduction, and then leach phosphorus from the residue by acid leaching. This can achieve low-cost sludge treatment and obtain high-concentration phosphorus-containing liquid, which is beneficial for phosphorus extraction and has high economic benefits. Summary of the Invention

[0006] The purpose of this invention is to solve the above-mentioned technical problems by providing a pretreatment method for phosphorus recovery from sludge. The method is simple to operate and low in cost. It not only reduces the volume of sludge but also realizes the resource recovery of phosphorus from sludge, thus preventing environmental pollution caused by phosphorus loss from wastewater.

[0007] This invention provides the following technical solution: a pretreatment method for phosphorus recovery from sludge, characterized in that: the sludge is reduced in volume by aerobic biological decomposition and drying, phosphorus-containing components are screened and fixed, and then recovered by acid leaching. The specific method steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Building and Activating the Mushroom Bed: Aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, oil-degrading bacteria, actinomycetes, filamentous fungi) and enzyme preparations (cellulase, hemicellulase, ligninase) are added to brown sugar water for activation. The activated microorganisms are then mixed evenly with chicken manure and bamboo powder to obtain mixed microorganisms. The mixed microorganisms are then loaded onto irregularly shaped wooden blocks of 3-5cm in size. The mushroom bed is now complete. Step 2, Sludge Addition: Add domestic sludge to the activated bacterial bed in Step 1 every 48 hours and mix evenly; aerate once every two days for 150 minutes. The mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the temperature of the bacterial bed at 65-75℃, evaporate the water, and achieve sludge reduction treatment to obtain reduced sludge. (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use a 60-100 mesh sieve to screen the residue obtained in Step 1 a second time, and separate out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is leached with acid for 0.5-2 hours to leach out the phosphorus and recover it.

[0008] The aerobic microorganisms are obtained by mixing lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, lipid-degrading bacteria, actinomycetes, and filamentous bacteria in a ratio of 1:1:0.1:0.1:0.05:0.03:0.1.

[0009] The enzyme preparation is prepared by mixing vitamin C, hemicellulase and ligninase in a ratio of 1:1:0.5.

[0010] The mixing mass ratio of the microorganisms and enzyme preparations is 10:1-25:1. After mixing, the mixture is added to 5%-10% brown sugar water for activation for 24 hours to obtain activated microorganisms. The microorganisms, enzyme preparations and brown sugar water are mixed in a ratio of 1:0.04:25-1:0.1:25 to obtain activated microorganisms.

[0011] The activated microorganisms were mixed with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms.

[0012] The mixture of microorganisms is applied to the wood blocks, wherein 300-400 kg of the mixture is applied to every 30 m³ of wood blocks.

[0013] The ratio of wood blocks to sludge (V / m) is 30:1 (V / m).

[0014] The acid may be sulfuric acid, oxalic acid, or citric acid, and the concentration of the acid is 0.1 mol / L to 0.2 mol / L.

[0015] The solid-liquid ratio of the phosphorus-containing solid to the acid is 10-50 (V / m).

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention achieves low-cost and high-efficiency volume reduction treatment of sludge through aerobic decomposition and drying; 2. This invention can enrich phosphorus in sludge, which is beneficial for acid leaching and phosphorus extraction; 3. This invention reduces the amount of acid used during the acid leaching process, thereby lowering extraction costs; 4. The present invention simultaneously achieves sludge reduction and phosphorus extraction pretreatment during the pretreatment process, which is convenient and efficient, and makes necessary preparations for phosphorus recovery. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram showing the effect of different sulfuric acid concentrations on phosphorus release amount and phosphorus release rate according to the present invention. Figure 2 This is a schematic diagram showing the effect of leaching time on phosphorus release amount and phosphorus release rate in this invention; Figure 3 This is a schematic diagram showing the solid-liquid ratio of the phosphorus-containing solid and the acid in this invention; Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0020] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention. Example 1

[0021] A pretreatment method for phosphorus recovery from sludge, characterized by: reducing the volume of sludge through aerobic biological decomposition and drying; fixing phosphorus-containing components through screening; and recovering phosphorus through acid leaching. The specific steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Establish and activate the microbial bed: 1. Place aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, lipid-degrading bacteria, actinomycetes, and filamentous fungi) in a ratio of 1:1:0.1:0.1: After mixing the microorganisms (0.05:0.03:0.1) and enzyme preparations (vitaminase, hemicellulase, and ligninase in a ratio of 1:1:0.5) separately, mix them again thoroughly according to the mixing mass ratio of microorganisms and enzyme preparations of 10:1-25:1. Then, mix the microorganisms, enzyme preparations, and brown sugar water in a ratio of 1:0.04:25-1:0.1:25 to obtain activated microorganisms. Add the above mixture to 5% brown sugar water for activation to obtain activated microorganisms. Mix the activated microorganisms with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms. Place 300-400 kg of the mixture onto 3cm irregularly shaped wooden blocks in a 30m³ block. The mycelium bed construction and activation are complete. Step 2, Sludge Addition: Add domestic sewage sludge to the activated bacterial bed from Step 1 every 48 hours and mix thoroughly; the ratio of wood blocks to sludge (V / m) is 30:1 (V / m), aerate once every two days for 150 minutes, the mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the bacterial bed temperature at 65℃, evaporate the water, achieve sludge reduction treatment, and obtain reduced sludge; (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use a 60-mesh sieve to screen the residue obtained in Step 1 a second time, separating out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is subjected to acid leaching treatment with a solid-liquid ratio of phosphorus-containing solid to acid of 10 (V / m), wherein the acid is sulfuric acid with a concentration of 0.1 mol / L, the leaching time is 0.5 h, the phosphorus is leached out and the phosphorus is recovered. Example 2

[0022] A pretreatment method for phosphorus recovery from sludge, characterized by: reducing the volume of sludge through aerobic biological decomposition and drying; fixing phosphorus-containing components through screening; and recovering phosphorus through acid leaching. The specific steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Building and Activating the Mycobacterial Bed: 1. Mix aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, oil-degrading bacteria, actinomycetes, and filamentous fungi in a ratio of 1:1:0.1:0.1:0.05:0.03:0.1) and enzyme preparations (vitaminase, hemicellulase, and ligninase in a ratio of 1:1:0.5) separately. Then, mix the mixture again at a mass ratio of 10:1 to 25:1. Mix the microorganisms, enzyme preparations, and brown sugar water in a ratio of 1:0.04:25 to 1:0.1:25 to obtain activated microorganisms. Activate the mixture by adding it to 8% brown sugar water. Mix the activated microorganisms with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms. Load 350kg of the mixed microorganisms onto irregularly shaped wooden blocks (30m³) and place them on the blocks. The mycobacterial bed construction and activation are complete. Step 2, Sludge Addition: Add domestic sewage sludge to the activated bacterial bed from Step 1 every 48 hours and mix thoroughly; the ratio of wood blocks to sludge (V / m) is 30:1 (V / m), aerate once every two days for 150 minutes, the mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the bacterial bed temperature at 70℃, evaporate the water, achieve sludge reduction treatment, and obtain reduced sludge; (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use a 70-mesh sieve to screen the residue obtained in Step 1 a second time, separating out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is subjected to acid leaching treatment with a solid-liquid ratio of phosphorus-containing solid to acid of 30 (V / m), wherein the concentration of acid is 0.15mol / L sulfuric acid, the leaching time is 1.5h, the phosphorus is leached out and the phosphorus is recovered. Example 3

[0023] A pretreatment method for phosphorus recovery from sludge, characterized by: reducing the volume of sludge through aerobic biological decomposition and drying; fixing phosphorus-containing components through screening; and recovering phosphorus through acid leaching. The specific steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Building and Activating the Mycobacterial Bed: 1. Mix aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, oil-degrading bacteria, actinomycetes, and filamentous fungi in a ratio of 1:1:0.1:0.1:0.05:0.03:0.1) and enzyme preparations (vitaminase, hemicellulase, and ligninase in a ratio of 1:1:0.5) separately. Then, mix the mixture again at a mass ratio of 10:1 to 25:1. Mix the microorganisms, enzyme preparations, and brown sugar water in a ratio of 1:0.04:25 to 1:0.1:25 to obtain activated microorganisms. Activate the mixture by adding it to 9% brown sugar water. Mix the activated microorganisms with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms. Load 380 kg of the mixed microorganisms onto irregularly shaped 5 cm wooden blocks using 30 m³ blocks as substrate. The mycobacterial bed construction and activation are now complete. Step 2, Sludge Addition: Add domestic sewage sludge to the activated bacterial bed from Step 1 every 48 hours and mix thoroughly; the ratio of wood blocks to sludge (V / m) is 30:1 (V / m), aerate once every two days for 150 minutes, the mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the bacterial bed temperature at 75℃, evaporate the water, achieve sludge reduction treatment, and obtain reduced sludge; (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use an 80-mesh sieve to screen the residue obtained in Step 1 a second time, separating out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is subjected to acid leaching treatment with a solid-liquid ratio of 40 (V / m) between the phosphorus-containing solid and the acid. The concentration of the acid is 0.2 mol / L sulfuric acid, and the leaching time is 2 hours. The phosphorus is leached out and recovered. Example 4

[0024] A pretreatment method for phosphorus recovery from sludge, characterized by: reducing the volume of sludge through aerobic biological decomposition and drying; fixing phosphorus-containing components through screening; and recovering phosphorus through acid leaching. The specific steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Building and Activating the Mycobacterial Bed: 1. Mix aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, oil-degrading bacteria, actinomycetes, and filamentous fungi in a ratio of 1:1:0.1:0.1:0.05:0.03:0.1) and enzyme preparations (vitaminase, hemicellulase, and ligninase in a ratio of 1:1:0.5) separately. Then, mix the microorganisms and enzyme preparations again at a mass ratio of 10:1. Mix the microorganisms, enzyme preparations, and brown sugar water in a ratio of 1:0.04:25 to obtain activated microorganisms. Activate the above mixture by adding it to 10% brown sugar water. Mix the activated microorganisms with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms. Load 400kg of the mixed microorganisms onto irregularly shaped 3cm wooden blocks in a 30m³ block. The mycobacterial bed construction and activation are complete. Step 2, Sludge Addition: Add domestic sewage sludge to the activated bacterial bed from Step 1 every 48 hours and mix thoroughly; the ratio of wood blocks to sludge (V / m) is 30:1 (V / m), aerate once every two days for 150 minutes, the mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the bacterial bed temperature at 65℃, evaporate the water, achieve sludge reduction treatment, and obtain reduced sludge; (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use an 80-mesh sieve to screen the residue obtained in Step 1 a second time, separating out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is subjected to acid leaching treatment with a solid-liquid ratio of phosphorus-containing solid to acid of 10 (V / m), wherein the concentration of acid is 0.1 mol / L oxalic acid, the leaching time is 0.5 h, the phosphorus is leached out and the phosphorus is recovered. Example 5

[0025] A pretreatment method for phosphorus recovery from sludge, characterized by: reducing the volume of sludge through aerobic biological decomposition and drying; fixing phosphorus-containing components through screening; and recovering phosphorus through acid leaching. The specific steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Building and Activating the Mycobacterial Bed: 1. Mix aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, oil-degrading bacteria, actinomycetes, and filamentous fungi in a ratio of 1:1:0.1:0.1:0.05:0.03:0.1) and enzyme preparations (vitaminase, hemicellulase, and ligninase in a ratio of 1:1:0.5) separately. Then, mix the mixture again thoroughly at a mass ratio of 10:1 to 25:1. Mix the microorganisms, enzyme preparations, and brown sugar water in a ratio of 1:0.04:25 to 1:0.1:25 to obtain activated microorganisms. Add the mixture to 10% brown sugar water to activate the microorganisms. Mix the activated microorganisms with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms. Place 400kg of the mixed microorganisms onto irregularly shaped wooden blocks (30m³) and load them onto the blocks. The mycobacterial bed construction and activation are complete. Step 2, Sludge Addition: Add domestic sewage sludge to the activated bacterial bed from Step 1 every 48 hours and mix thoroughly; the ratio of wood blocks to sludge (V / m) is 30:1 (V / m), aerate once every two days for 150 minutes, the mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the bacterial bed temperature at 75℃, evaporate the water, achieve sludge reduction treatment, and obtain reduced sludge; (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use a 100-mesh sieve to screen the residue obtained in Step 1 a second time, separating out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is subjected to acid leaching treatment with a solid-liquid ratio of 50 (V / m) between the phosphorus-containing solid and the acid. The concentration of the acid is 0.1mol / L-0.2mol / L oxalic acid, and the leaching time is 2h to leach out the phosphorus and recover it. Example 6

[0026] A pretreatment method for phosphorus recovery from sludge, characterized by: reducing the volume of sludge through aerobic biological decomposition and drying; fixing phosphorus-containing components through screening; and recovering phosphorus through acid leaching. The specific steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Building and Activating the Mycobacterial Bed: 1. Mix aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, oil-degrading bacteria, actinomycetes, and filamentous fungi in a ratio of 1:1:0.1:0.1:0.05:0.03:0.1) and enzyme preparations (vitaminase, hemicellulase, and ligninase in a ratio of 1:1:0.5) separately. Then, mix the mixture again at a mass ratio of 10:1 to 25:1. Mix the microorganisms, enzyme preparations, and brown sugar water in a ratio of 1:0.04:25 to 1:0.1:25 to obtain activated microorganisms. Activate the mixture by adding it to 9% brown sugar water. Mix the activated microorganisms with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms. Load 390 kg of the mixed microorganisms onto irregularly shaped 5 cm wooden blocks using 30 m³ of wood blocks. The mycobacterial bed construction and activation are now complete. Step 2, Sludge Addition: Add domestic sewage sludge to the activated bacterial bed from Step 1 every 48 hours and mix thoroughly; the ratio of wood blocks to sludge (V / m) is 30:1 (V / m), aerate once every two days for 150 minutes, the mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the bacterial bed temperature at 70℃, evaporate the water, achieve sludge reduction treatment, and obtain reduced sludge; (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use a 90-mesh sieve to screen the residue obtained in Step 1 a second time, separating out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is subjected to acid leaching treatment with a solid-liquid ratio of phosphorus-containing solid to acid of 45 (V / m), wherein the concentration of acid is 0.2 mol / L citric acid, the leaching time is 1.8 h, the phosphorus is leached out and the phosphorus is recovered. Example 7

[0027] A pretreatment method for phosphorus recovery from sludge, characterized by: reducing the volume of sludge through aerobic biological decomposition and drying; fixing phosphorus-containing components through screening; and recovering phosphorus through acid leaching. The specific steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Building and Activating the Mycobacterial Bed: 1. Mix aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, oil-degrading bacteria, actinomycetes, and filamentous fungi in a ratio of 1:1:0.1:0.1:0.05:0.03:0.1) and enzyme preparations (vitaminase, hemicellulase, and ligninase in a ratio of 1:1:0.5) separately. Then, mix the mixture again at a mass ratio of 10:1 to 25:1. Mix the microorganisms, enzyme preparations, and brown sugar water in a ratio of 1:0.04:25 to 1:0.1:25 to obtain activated microorganisms. Activate the mixture by adding it to 10% brown sugar water. Mix the activated microorganisms with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms. Load 400 kg of the mixed microorganisms onto irregularly shaped 5 cm wooden blocks using 30 m³ blocks. The mycobacterial bed construction and activation are now complete. Step 2, Sludge Addition: Add domestic sewage sludge to the activated bacterial bed from Step 1 every 48 hours and mix thoroughly; the ratio of wood blocks to sludge (V / m) is 30:1 (V / m), aerate once every two days for 150 minutes, the mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the bacterial bed temperature at 65℃, evaporate the water, achieve sludge reduction treatment, and obtain reduced sludge; (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use a 75-mesh sieve to screen the residue obtained in Step 1 a second time, separating out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is subjected to acid leaching treatment with a solid-liquid ratio of phosphorus-containing solid to acid of 10 (V / m). The concentration of acid is 0.1mol / L-0.2mol / L citric acid, and the leaching time is 2h to leach out and recover the phosphorus. Example 8

[0028] A pretreatment method for phosphorus recovery from sludge, characterized by: reducing the volume of sludge through aerobic biological decomposition and drying; fixing phosphorus-containing components through screening; and recovering phosphorus through acid leaching. The specific steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Building and Activating the Mycobacterial Bed: 1. Mix aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, oil-degrading bacteria, actinomycetes, and filamentous fungi in a ratio of 1:1:0.1:0.1:0.05:0.03:0.1) and enzyme preparations (vitaminase, hemicellulase, and ligninase in a ratio of 1:1:0.5) separately. Then, mix the mixture again at a mass ratio of 10:1 to 25:1. Mix the microorganisms, enzyme preparations, and brown sugar water in a ratio of 1:0.04:25 to 1:0.1:25 to obtain activated microorganisms. Activate the mixture by adding it to 5% brown sugar water. Mix the activated microorganisms with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms. Load 300 kg of the mixed microorganisms onto irregularly shaped 3cm wooden blocks (30 m³ each). The mycobacterial bed construction and activation are complete. Step 2, Sludge Addition: Add domestic sewage sludge to the activated bacterial bed from Step 1 every 48 hours and mix thoroughly; the ratio of wood blocks to sludge (V / m) is 30:1 (V / m), aerate once every two days for 150 minutes, the mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the bacterial bed temperature at 65℃, evaporate the water, achieve sludge reduction treatment, and obtain reduced sludge; (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use a 60-mesh sieve to screen the residue obtained in Step 1 a second time, separating out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is subjected to acid leaching treatment with a solid-liquid ratio of phosphorus-containing solid to acid of 20 (V / m). The concentration of acid is 0.1mol / L-0.2mol / L citric acid, and the leaching time is 0.5h to leach out and recover the phosphorus.

[0029] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations; any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A pretreatment method for phosphorus recovery from sludge, characterized in that: The sludge is reduced in volume by aerobic biological decomposition and drying. After phosphorus fixation by screening, phosphorus is recovered through acid leaching. The specific steps are as follows: (1) Aerobic biological decomposition and drying to reduce the volume of sludge: Step 1: Building and Activating the Mushroom Bed: Aerobic microorganisms (lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, oil-degrading bacteria, actinomycetes, filamentous fungi) and enzyme preparations (cellulase, hemicellulase, ligninase) are added to brown sugar water for activation. The activated microorganisms are then mixed evenly with chicken manure and bamboo powder to obtain mixed microorganisms. The mixed microorganisms are then loaded onto irregularly shaped wooden blocks of 3-5cm in size. The mushroom bed is now complete. Step 2, Sludge Addition: Add domestic sludge to the activated bacterial bed in Step 1 every 48 hours and mix evenly; aerate once every two days for 150 minutes. The mixed microorganisms decompose the organic matter in the sludge, break the cell walls, generate biological heat, maintain the temperature of the bacterial bed at 65-75℃, evaporate the water, and achieve sludge reduction treatment to obtain reduced sludge. (2) Residue screening treatment: Step 1: When the gaps in the wood block are blocked by the residue of sludge, use a 5mm mesh screen to separate the wood block and the residue, and screen out the residue to obtain the residue. Step 2: Use a 60-100 mesh sieve to screen the residue obtained in Step 1 a second time, and separate out the fine particles of the residue to obtain phosphorus-containing solids; (3) Acid leaching treatment: The phosphorus-containing solid obtained in the above step is leached with acid for 0.5-2 hours to leach out the phosphorus and recover it.

2. The pretreatment method for phosphorus recovery from sludge according to claim 1, characterized in that: The aerobic microorganisms are obtained by mixing lignin-degrading bacteria, cellulose-degrading bacteria, Bacillus, lactic acid bacteria, lipid-degrading bacteria, actinomycetes, and filamentous bacteria in a ratio of 1:1:0.1:0.1:0.05:0.03:0.

1.

3. The pretreatment method for phosphorus recovery from sludge according to claim 1, characterized in that: The enzyme preparation is prepared by mixing vitamin C, hemicellulase and ligninase in a ratio of 1:1:0.

5.

4. The pretreatment method for phosphorus recovery from sludge according to claim 1, characterized in that: The mixing mass ratio of the microorganisms and enzyme preparations is 10:1-25:

1. After mixing, the mixture is added to 5%-10% brown sugar water for activation for 24 hours to obtain activated microorganisms. The microorganisms, enzyme preparations and brown sugar water are mixed in a ratio of 1:0.04:25-1:0.1:25 to obtain activated microorganisms.

5. The pretreatment method for phosphorus recovery from sludge according to claim 1, characterized in that: The activated microorganisms were mixed with chicken manure and bamboo powder in a ratio of 1:10:2 to obtain mixed microorganisms.

6. The pretreatment method for phosphorus recovery from sludge according to claim 1, characterized in that: The mixture of microorganisms is applied to the wood blocks, wherein 300-400 kg of the mixture is applied to every 30 m³ of wood blocks.

7. The pretreatment method for phosphorus recovery from sludge according to claim 1, characterized in that: The ratio of wood blocks to sludge (V / m) is 30:1 (V / m).

8. The pretreatment method for phosphorus recovery from sludge according to claim 1, characterized in that: The acid may be sulfuric acid, oxalic acid, or citric acid, and the concentration of the acid is 0.1 mol / L to 0.2 mol / L.

9. The pretreatment method for phosphorus recovery from sludge according to claim 1, characterized in that: The solid-liquid ratio of the phosphorus-containing solid to the acid is 10-50 (V / m).

Images