Cooperative treatment system and method for breeding manure, farmland recession and processing waste

Abstract

The invention relates to a breeding manure, farmland recession and processing waste cooperative treatment system, which comprises a breeding plant, a planting field, a processing plant, a manure and urine separation device, a mixed anaerobic fermentation device, a sealed anaerobic pond biogas manure preparation device, a biogas power generation device, a breeding sewage phosphorus recovery device, an artificial wetland, a reservoir pond and a pond water reuse system, the method is characterized in that a mixture of solid excrement and vinasse of a processing plant is subjected to fermentation treatment, and the aquaculture wastewater is subjected to phosphorus removal by adopting a magnesium ammonium phosphate crystallization method and a hydroxyl calcium phosphate crystallization method. The treatment method comprises the following steps: a) carrying out solid-liquid separation on the breeding manure; b) fermenting to produce gas; c) removing phosphorus; d) farmland water recession treatment; e) purifying the water body of the wetland and the pond; (f) recycling pond water; and g) cyclic utilization of substances and energy. According to the treatment system and method, a scientific and reasonable collaborative development method is provided for ecological comprehensive treatment of livestock and poultry breeding pollution, agricultural non-point source pollution control and drainage basin ecological environment protection.

Description

Technical Field

[0001] The present invention relates to a "planting + raising + processing" livestock and poultry manure coordinated treatment system and method, more specifically, to a breeding manure, farmland drainage and processing waste coordinated treatment system and method. Background Art

[0002] In recent years, my country's livestock and poultry farming industry has developed rapidly, and the number of pigs, sheep and small livestock and poultry stocks ranks among the top in the world. About 3.8 billion tons of livestock and poultry manure is produced each year, of which about 40% is not effectively treated and utilized. This has led to COD and TP emissions from livestock and poultry manure accounting for about 38.31% and 37.09% of the total national pollutant emissions, respectively. It has become an important source of ecological and environmental pollution in my country, and it is urgent to carry out comprehensive management and resource utilization of livestock and poultry manure. At present, the disposal of livestock and poultry manure in my country has problems such as high pollutant concentration, large amount of production, low recycling rate, serious non-point source pollution of farmland, imperfect monitoring method system, and lack of comprehensive management model. It has always been the focus and difficulty of my country's ecological environment protection and pollution prevention and control battle, and it is related to the construction of ecological civilization. Reasonable and effective treatment of livestock and poultry manure is of great significance to improving the ecological environment quality of the basin and promoting the green development of livestock and poultry farming. Summary of the invention

[0003] In order to overcome the disadvantages of the above-mentioned technical problems, the present invention provides a system and method for the coordinated treatment of livestock manure, farmland drainage and processing waste.

[0004] The system for coordinating the treatment of livestock manure, farmland drainage and processing waste of the present invention comprises a breeding farm, a planting field, a processing plant, a feces and urine separation device, a mixed anaerobic fermentation device, a closed anaerobic pond biogas fertilizer preparation device, a biogas power generation device, a breeding wastewater phosphorus recovery device, an artificial wetland, a reservoir pond and a pond water reuse system. The breeding farm is used for livestock and poultry breeding, the planting field is used for crop planting, the processing plant processes the crops in the planting field and the livestock and poultry in the breeding farm and produces distiller's grains; the feces and urine separation device separates the livestock manure generated by the breeding farm into solid feces and breeding wastewater mainly composed of urine; the artificial wetland and the reservoir pond are built between the planting field and the breeding farm, and the artificial wetland and the reservoir pond are connected; the system is characterized in that In: the mixed anaerobic fermentation device ferments the mixture of solid feces produced by the feces and urine separation device and the wine dregs produced by the processing plant, and the biogas produced by the fermentation is used to generate electricity through the biogas power generation device and / or to generate natural gas for use by the processing plant after being treated; the closed anaerobic pond biogas preparation device anaerobically treats the solid-liquid mixture produced by the mixed anaerobic fermentation device to produce biogas residues and biogas liquids, and the produced biogas residues and biogas liquids are returned to the field after being treated; the aquaculture wastewater phosphorus recovery device uses the magnesium ammonium phosphate crystallization method and the hydroxy calcium phosphate crystallization method to remove phosphorus from the aquaculture wastewater produced by the feces and urine separation device, and the produced calcium hydroxy phosphate precursor and magnesium ammonium phosphate are returned to the field as fertilizers, and the produced wastewater is discharged into the artificial wetland; The drainage water from the planting fields is discharged into the artificial wetland through the ecological channel. The artificial wetland and reservoir remove the COD, phosphorus and ammonia nitrogen in the waste liquid discharged from the drainage water from the planting fields and the phosphorus recovery device of the aquaculture wastewater. The water in the reservoir after treatment is recharged to the farmland through the pond water reuse system or used as clean water for the breeding farm. The crops produced by the planting fields are used as feed for the breeding farm and raw materials for the processing plant. The accessories produced by the processing industry are used as fertilizers for planting troughs and feed for the breeding farm.

[0005] The collaborative treatment system for aquaculture manure, farmland drainage and processing waste of the present invention has a matrix of an artificial wetland with coastal wetland sediments rich in halophilic bacteria and anaerobic bacteria, an artificial floating island and a photobioreactor are arranged in the reservoir pond, aquatic plants are planted on the artificial floating island, and the photobioreactor is a microalgae wall-attached photobioreactor.

[0006] The collaborative treatment system for livestock manure, farmland drainage and processing waste of the present invention comprises a primary channel, a farm channel, a ditches, a branch channel and a main channel which are sequentially connected, ecological slope protection is arranged on both sides of the ecological channel, an ecological dam and a vegetation filter belt are arranged in the ecological channel, and biochar-chitosan composite microspheres are arranged in the ecological slope protection.

[0007] The processing method of the collaborative processing system of livestock manure, farmland drainage and processing waste of the present invention is characterized by being achieved through the following steps: a). Solid-liquid separation of livestock and poultry manure; Use a manure and urine separation device to separate the livestock and poultry manure produced by the breeding farm into solid manure and livestock and poultry wastewater mainly composed of urine, so that the solid manure and breeding wastewater can be treated separately in the future; b) Mixed anaerobic fermentation to produce gas: solid feces and distiller's grains produced by the processing plant are mixed in a mass ratio of 5:5 to 7:3, and then placed in a mixed anaerobic fermentation device for anaerobic fermentation. The biogas produced by the fermentation is processed to form natural gas for use by the processing plant, and the biogas is used to generate electricity for use by the processing plant through a biogas power generation device; c). Phosphorus removal from aquaculture wastewater: The aquaculture wastewater generated by solid-liquid separation of livestock and poultry manure is dephosphorized by the ammonium magnesium phosphate crystallization method and the hydroxy calcium phosphate crystallization method in the aquaculture wastewater phosphorus recovery device, and the precursor of the hydroxy calcium phosphate and the ammonium magnesium phosphate formed are returned to the field as fertilizers, and the generated wastewater is discharged into the artificial wetland for further treatment; d). Preliminary treatment of farmland drainage: In the process of flowing through the ecological canal, the drainage from the cultivated field will flow through the primary canal, agricultural canal, ditches, branch canals and main canals in sequence, and will be purified by the ecological slope protection, ecological dam and vegetation filter belt in the ecological canal. The biochar-chitosan composite microspheres in the ecological slope protection, the plants and microorganisms in the ecological dam and the vegetation filter belt can effectively remove phosphorus and ammonia nitrogen in the drainage from the farmland. The drainage from the farmland treated by the ecological canal will be discharged into the artificial wetland; e) Purification of water bodies in wetlands and reservoirs; when farmland drainage and aquaculture wastewater flow through artificial wetlands, the plants and microorganisms in the artificial wetlands consume COD, phosphorus and ammonia nitrogen in the water, thus achieving further treatment of the water body; after the water body in the artificial wetland flows into the reservoir, the microalgae on the inner wall of the photobioreactor and the aquatic plants on the artificial floating island further remove COD, phosphorus and ammonia nitrogen, so that the water quality in the reservoir reaches the quality that can be reused; f). Reservoir and pond water reuse: The pond water reuse system pumps water from the reservoir and pond to the planting fields to realize the re-injection of farmland water; the pond water reuse system pumps water from the reservoir and pond to the breeding farm as flushing water for livestock and poultry breeding sites; g). Recycling of materials and energy; the crops produced by the planting fields are used as feed for the breeding farms and raw materials for the processing plants, the livestock and poultry produced by the breeding farms provide processing raw materials for the processing plants, the accessories produced by the processing plants are used as fertilizers for the planting industry and feed for the breeding farms, and the wine grains produced by the processing plants are used as raw materials for mixed anaerobic fermentation and gas production, so as to realize the recycling of materials and energy between the breeding farms, planting fields and processing plants.

[0008] In the method for treating livestock manure, farmland drainage and processing waste in a coordinated treatment system of the present invention, the phosphorus removal from livestock wastewater in step c) is specifically achieved by the following steps: c-1). Preparing dolomite solution; preparing dolomite solution by the following steps: c-1-1). Crushing of dolomite: crushing the blocky dolomite with a crusher, passing the crushed dolomite through a 100-mesh sieve, and leaving the sieve-off material for later use; c-1-2) Acidification reaction of dolomite; first, a sufficient amount of the undersize dolomite obtained in step c-1-1) is taken and placed in a container, and 3.4 mL of hydrochloric acid having a mass concentration of 6 mol / L is added to 1 g of dolomite, and hydrochloric acid is added to the container, and the reaction is acidified at room temperature for 180 min to obtain a dolomite solution rich in calcium and magnesium ions; c-2). Phosphorus removal from aquaculture wastewater: Phosphorus removal from aquaculture wastewater is carried out through the following steps: c-2-1). Adjustment of pH value of aquaculture wastewater: First, adjust the pH value of aquaculture wastewater to pH=9 according to the initial pH value of aquaculture wastewater; c-2-2). Addition of dolomite solution; according to the dosage of Ca:P=1.67:1, add the corresponding amount of dolomite solution to the aquaculture wastewater; c-2-3) Phosphorus removal reaction; at room temperature, the reaction was stirred at a stirring speed of 200 r / min for 180 min to achieve effective phosphorus removal from aquaculture wastewater; c-2-4). After the phosphorus removal reaction is completed, the solution after the reaction is separated into solid and liquid. The precursor of calcium hydroxyphosphate and magnesium ammonium phosphate generated by the phosphorus removal reaction are returned to the field as fertilizer, and the liquid is discharged into the artificial wetland as aquaculture wastewater for further treatment.

[0009] The beneficial effects of the present invention are as follows: the livestock and poultry manure, farmland drainage and processing waste coordinated treatment system and method of the present invention, the livestock and poultry manure generated by the breeding farm is first separated into solid and liquid by a manure and urine separation device, the separated solid manure is mixed with the distiller's grains provided by the processing plant and then fermented and gasified by a mixed anaerobic fermentation device, the generated biogas is processed to form natural gas for direct use by the processing plant, or is generated by a biogas power generation device for use by the processing plant, the fermented solid and liquid are passed through a closed anaerobic pond biogas fertilizer preparation device to produce biogas residue and biogas liquid and returned to the field, the coordinated treatment of livestock and poultry manure and distiller's grains is achieved, clean energy is provided for the processing plant, fertilizer is provided for the planting field, the amount of chemical fertilizers and pesticides applied to the farmland is reduced, and The non-point source pollution of farmland is reduced; the separated aquaculture wastewater is subjected to the magnesium ammonium phosphate crystallization method and the calcium hydroxyphosphate crystallization method for phosphorus removal in the aquaculture wastewater phosphorus recovery device, and the phosphorus in the aquaculture wastewater is converted into the precursor of calcium hydroxyphosphate and magnesium ammonium phosphate fertilizer and returned to the field, thus realizing the recovery and utilization of phosphorus element; the farmland drainage water from the planting field is first treated by the ecological slope protection, ecological dam and vegetation filter belt in the ecological channel to remove the phosphorus and ammonia nitrogen in the farmland drainage water, and then treated by artificial wetlands and reservoirs to further remove COD, phosphorus and ammonia nitrogen in the farmland drainage water and aquaculture wastewater, so that the water in the reservoirs and ponds can meet the reuse requirements; the water in the reservoirs and ponds is recharged to the farmland or cleaned in the aquaculture plant through the pond water reuse system. It can be seen that the system and method for coordinated treatment of livestock manure, farmland drainage and processing waste of the present invention realize the ecological treatment of separated feces and urine in livestock and poultry farms, liquid fertilizer extraction and biogas fermentation, and comprehensive resource utilization of clean return of manure to the fields, as well as ecological prevention of farmland drainage surface source pollution, and propose a new method for comprehensive management of livestock and poultry breeding pollution, which proposes a scientific and reasonable coordinated development method for the comprehensive ecological management of livestock and poultry breeding pollution, control of agricultural non-point source pollution, and protection of watershed ecological environment.

[0010] Furthermore, by setting up ecological slope protection containing biochar-chitosan composite microspheres in the ecological channel, the adsorption area of ​​microorganisms was increased, and the adsorption capacity and purification capacity of microorganisms were improved; by adding coastal wetland sediments to the bottom matrix of the artificial wetland and utilizing the rich halophilic bacteria and anaerobic bacteria in the coastal wetland sediments, the removal capacity of COD in aquaculture wastewater was effectively increased or decreased; by setting up photobioreactors and artificial floating islands in the reservoir, the removal of phosphorus and ammonia nitrogen in farmland drainage and aquaculture wastewater was achieved.

[0011] Furthermore, in the process of removing phosphorus from aquaculture wastewater by using magnesium ammonium phosphate crystallization method and calcium hydroxyphosphate crystallization method, easily available and low-cost dolomite is used to remove phosphorus from aquaculture wastewater, and the recovered products are mainly amorphous calcium phosphate and magnesium ammonium phosphate, the precursors of calcium hydroxyphosphate, which can be directly returned to farmland as fertilizers; at the same time, it can effectively reduce the economic cost of phosphorus removal by crystallization, and the raw material cost per ton of water treatment is only about 0.2 yuan, which is much lower than the traditional raw material cost of using MgCl2, MgSO4 and CaCl2 as calcium and magnesium sources. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the coordinated treatment system of livestock manure, farmland drainage and processing waste of the present invention.

[0013] In the figure: 1 breeding farm, 2 planting field, 3 processing plant, 4 feces and urine separation device, 5 mixed anaerobic fermentation device, 6 closed anaerobic pond biofertilizer preparation device, 7 biogas power generation device, 8 aquaculture wastewater phosphorus recovery device, 9 artificial wetland, 10 reservoir pond, 11 artificial floating island, 12 photobioreactor, 13 coastal wetland sediment, 14 pond water reuse system, 15 ecological channel, 16 ecological slope protection, 17 ecological dam. DETAILED DESCRIPTION

[0014] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0015] like Figure 1 As shown, a schematic diagram of the coordinated treatment system of livestock manure, farmland drainage and processing waste of the present invention is given, which is composed of a breeding farm 1, a planting field 2, a processing plant 3, a feces and urine separation device 4, a mixed anaerobic fermentation device 5, a closed anaerobic pond biogas fertilizer preparation device 6, a biogas power generation device 7, a breeding wastewater phosphorus recovery device 8, an artificial wetland 9, a reservoir 10 and a pond water reuse system 14. The breeding farm 1, the planting field 2 and the processing plant 3 shown correspond to the breeding industry, the planting industry and the processing industry respectively; the breeding farm 1 is used for livestock and poultry breeding, and the feces and urine separation device 4 is used to separate the livestock and poultry manure into solid feces and breeding wastewater (mainly urine). The separation of solid feces and urine changes the traditional water-foam feces mixed treatment mode, and reduces the amount of feces and sewage generated from the source. The solid feces separated by the feces and urine separation device 4 is mixed with the wine lees produced by the processing plant 3, and an anaerobic fermentation gas is produced in the mixed anaerobic fermentation device 5, and the generated biogas is used for the processing plant.

[0016] The biogas generated by the mixed anaerobic fermentation device 5 can be processed and converted into natural gas for use by the processing plant 3, or it can be converted into electricity by the biogas power generation device 7 for use by the processing plant 3. The coordinated treatment of solid feces and vinasse solves the problem that the vinasse of agricultural product processing waste is difficult to treat alone, and can provide clean energy for the processing plant 3. The harmless coordinated disposal of pig manure and vinasse reduces carbon emissions. The solid and liquid residues after fermentation and gas production by the mixed anaerobic fermentation device 5 are then subjected to anaerobic fermentation treatment by the closed anaerobic pond biogas fertilizer preparation device 6, and the generated biogas residues and liquid are returned to the field as fertilizer.

[0017] The aquaculture wastewater phosphorus recovery device 8 shown removes phosphorus from the aquaculture wastewater generated after solid-liquid separation of livestock and poultry manure. The aquaculture wastewater phosphorus recovery device 8 removes phosphorus by using magnesium ammonium phosphate crystallization method and hydroxy calcium phosphate crystallization method, and uses dolomite solution as a cheap source of calcium and magnesium to remove phosphorus from the aquaculture wastewater. The precursor of calcium hydroxy phosphate and magnesium ammonium phosphate generated after phosphorus removal from the aquaculture wastewater are returned to the fields as fertilizers, and the generated wastewater is discharged into an artificial wetland.

[0018] Due to the use of fertilizers and agriculture in the existing planting industry, the farmland drainage contains a large amount of phosphorus and ammonia nitrogen. If the farmland drainage is not purified, it will cause serious non-point source pollution. Therefore, the planting field 2 shown first uses an ecological channel 15 to treat the farmland drainage, and then purifies it through the artificial wetland 9 and the reservoir 10. The ecological channel 15 shown is composed of interconnected gross channels, agricultural channels, ditches, branch channels and main channels from the farmland to the artificial wetland 9 end, so that the farmland drainage is discharged into the artificial wetland through gross channels, agricultural channels, ditches, branch channels and main channels in sequence. Ecological slope protection 16 is set on both sides of the ecological channel 15, and an ecological dam 17 and a vegetation filter belt are set in the ecological channel 15. Biochar-chitosan composite microspheres are set in the ecological slope protection 16.

[0019] In this way, in the process of farmland drainage flowing through the ecological channel 15, it will be treated by the ecological slope protection 16, the ecological dam 17 and the vegetation filter belt to remove phosphorus, ammonia nitrogen in the farmland drainage water. The biochar-chitosan composite microspheres use biochar prepared from large-scale and wide-area agricultural waste corn stalks as the adsorption main body, and are formed by chitosan coating. The strength of the adsorption microspheres is significantly improved, the solubility in water is reduced, and the stability of the ecological slope protection, the microbial adhesion and the pollutant adsorption capacity are improved. It can effectively reduce farmland drainage pollutants, strengthen the ecological function of ditch slope protection, and realize the resource utilization of major agricultural waste.

[0020] The substrate at the bottom of the artificial wetland 9 shown in the figure is added with coastal wetland sediments 13. The coastal wetland sediments 13 are rich in halophilic bacteria and anaerobic bacteria. Halophilic bacteria and anaerobic bacteria can interact with artificial wetland plants, improve the diversity, richness and uniformity index of soil microbial communities, and significantly improve the COD removal rate of farmland drainage and aquaculture wastewater. The artificial wetland 9 shown in the figure is connected to the reservoir 10. The reservoir 10 is provided with an artificial floating island 11 and a photobioreactor 12. Aquatic plants are planted on the artificial floating island 11. The photobioreactor 12 uses microalgae to adhere to the wall. The microalgae are cultivated and wastewater is treated by the wall-attached mode, which solves the problems of large land occupation and difficult harvesting of conventional microalgae wastewater resource technology, reduces the high energy consumption process of algae cell centrifugation in the traditional suspension culture mode, and can effectively reduce costs. The results show that compared with the traditional suspension mode, the microalgae biomass of the wall-attached culture technology increased by 4.5 times, and the removal rates of COD and phosphate in the wastewater increased by 40% and 23% respectively.

[0021] In this way, the farmland drainage and aquaculture wastewater are further treated in the artificial wetland 9 and the reservoir 10 to remove phosphorus, ammonia nitrogen and COD, and the water quality meets the reuse requirements. The pond water reuse system 14 pumps the water in the reservoir 10 to the planting field 2 to realize the recharging of the farmland drainage. At the same time, the water in the reservoir 10 can also be pumped to the breeding farm 1 as flushing water for livestock and poultry breeding sites.

[0022] At the same time, the crops produced by the planting field 2 are used as feed for the breeding farm 1 and raw materials for the processing plant 3, the livestock and poultry produced by the breeding farm 1 provide processing raw materials for the processing plant 3, the accessories produced by the processing plant 3 are used as fertilizers for the planting field 2 and feed for the breeding farm 1, and the grains produced by the processing plant 3 are used as raw materials for mixed anaerobic fermentation gas production, so as to realize the recycling of materials and energy among the breeding farm, planting field and processing plant.

[0023] The method for treating livestock manure, farmland drainage and processing waste in a coordinated treatment system is characterized by being achieved through the following steps: a). Solid-liquid separation of livestock and poultry manure; Use a manure and urine separation device to separate the livestock and poultry manure produced by the breeding farm into solid manure and livestock and poultry wastewater mainly composed of urine, so that the solid manure and breeding wastewater can be treated separately in the future; b) Mixed anaerobic fermentation to produce gas: solid feces and distiller's grains produced by the processing plant are mixed in a mass ratio of 5:5 to 7:3, and then placed in a mixed anaerobic fermentation device for anaerobic fermentation. The biogas produced by the fermentation is processed to form natural gas for use by the processing plant, and the biogas is used to generate electricity for use by the processing plant through a biogas power generation device; c). Phosphorus removal from aquaculture wastewater: The aquaculture wastewater generated by solid-liquid separation of livestock and poultry manure is dephosphorized by the ammonium magnesium phosphate crystallization method and the hydroxy calcium phosphate crystallization method in the aquaculture wastewater phosphorus recovery device, and the precursor of the hydroxy calcium phosphate and the ammonium magnesium phosphate formed are returned to the field as fertilizers, and the generated wastewater is discharged into the artificial wetland for further treatment; d). Preliminary treatment of farmland drainage: In the process of flowing through the ecological canal, the drainage from the cultivated field will flow through the primary canal, agricultural canal, ditches, branch canals and main canals in sequence, and will be purified by the ecological slope protection, ecological dam and vegetation filter belt in the ecological canal. The biochar-chitosan composite microspheres in the ecological slope protection, the plants and microorganisms in the ecological dam and the vegetation filter belt can effectively remove phosphorus and ammonia nitrogen in the drainage from the farmland. The drainage from the farmland treated by the ecological canal will be discharged into the artificial wetland; e) Purification of water bodies in wetlands and reservoirs; when farmland drainage and aquaculture wastewater flow through artificial wetlands, the plants and microorganisms in the artificial wetlands consume COD, phosphorus and ammonia nitrogen in the water, thus achieving further treatment of the water body; after the water body in the artificial wetland flows into the reservoir, the microalgae on the inner wall of the photobioreactor and the aquatic plants on the artificial floating island further remove COD, phosphorus and ammonia nitrogen, so that the water quality in the reservoir reaches the quality that can be reused; f). Reservoir and pond water reuse: The pond water reuse system pumps water from the reservoir and pond to the planting fields to realize the re-injection of farmland water; the pond water reuse system pumps water from the reservoir and pond to the breeding farm as flushing water for livestock and poultry breeding sites; g). Recycling of materials and energy; the crops produced by the planting fields are used as feed for the breeding farms and raw materials for the processing plants, the livestock and poultry produced by the breeding farms provide processing raw materials for the processing plants, the accessories produced by the processing plants are used as fertilizers for the planting industry and feed for the breeding farms, and the wine grains produced by the processing plants are used as raw materials for mixed anaerobic fermentation and gas production, so as to realize the recycling of materials and energy between the breeding farms, planting fields and processing plants.

[0024] In step c), the phosphorus removal of aquaculture wastewater uses inexpensive dolomite as a cheap calcium and magnesium source. Dolomite, as a natural mineral material, is a complex salt of calcium carbonate and magnesium carbonate, and its molecular formula is CaMg(CO3)2, which is an important calcium and magnesium resource. This is achieved specifically by the following steps: c-1). Preparing dolomite solution; preparing dolomite solution by the following steps: c-1-1). Crushing of dolomite: crushing the blocky dolomite with a crusher, passing the crushed dolomite through a 100-mesh sieve, and leaving the sieve-off material for later use; c-1-2) Acidification reaction of dolomite; first, a sufficient amount of the undersize dolomite obtained in step c-1-1) is taken and placed in a container, and 3.4 mL of hydrochloric acid having a mass concentration of 6 mol / L is added to 1 g of dolomite, and hydrochloric acid is added to the container, and the reaction is acidified at room temperature for 180 min to obtain a dolomite solution rich in calcium and magnesium ions; c-2). Phosphorus removal from aquaculture wastewater: Phosphorus removal from aquaculture wastewater is carried out through the following steps: c-2-1). Adjustment of pH value of aquaculture wastewater: First, adjust the pH value of aquaculture wastewater to pH=9 according to the initial pH value of aquaculture wastewater; c-2-2). Addition of dolomite solution; according to the dosage of Ca:P=1.67:1, add the corresponding amount of dolomite solution to the aquaculture wastewater; c-2-3) Phosphorus removal reaction; at room temperature, the reaction was stirred at a stirring speed of 200 r / min for 180 min to achieve effective phosphorus removal from aquaculture wastewater; c-2-4). After the phosphorus removal reaction is completed, the solution after the reaction is separated into solid and liquid. The precursor of calcium hydroxyphosphate and magnesium ammonium phosphate generated by the phosphorus removal reaction are returned to the field as fertilizer, and the liquid is discharged into the artificial wetland as aquaculture wastewater for further treatment.

[0025] In summary, the system and method for the coordinated treatment of livestock and poultry manure, farmland drainage and processing waste of the present invention is centered on the anaerobic preparation of biogas liquid fertilizer by mixing livestock and poultry manure and vinasse. By mixing and anaerobic fermenting agricultural product processing wastes such as pig manure and distiller's grains, the generated biogas is supplied to enterprises, which solves the problem that agricultural product processing wastes are difficult to treat separately and clean energy is in short supply, and achieves the harmless coordinated disposal of pig manure and distiller's grains, reducing carbon emissions. The generated biogas residue and liquid are applied to farmland as fertilizer, which reduces the application of fertilizers and pesticides, reduces agricultural production costs, and alleviates farmland non-point source pollution; agricultural products are used for the processing and utilization of products such as alcohol, breaking through the industry boundaries of the "planting + breeding + processing" manure resource comprehensive recycling utilization, forming a new model for the comprehensive resource management of livestock and poultry waste, achieving efficient closed-loop circulation of nutrients and energy in livestock and poultry manure and near-zero emissions of pollutants, and playing a significant demonstration and driving role in improving the quality and efficiency of the livestock and poultry breeding industry.

[0026] Furthermore, we have carried out a demonstration of the comprehensive utilization of livestock manure resources in the Zhongyu High-Efficiency Ecological Agriculture and Animal Husbandry Circular Economy Industrial Park in Binzhou City using the system and method for the coordinated treatment of livestock manure, farmland drainage and processing waste of the present invention. By analyzing the carbon material flow of the industrial park, we have calculated the carbon emission reduction benefits of different industries such as livestock, planting and processing. Taking the annual output of 100,000 pigs and 3,000 acres of planting demonstration fields in the industrial park as an example, about 9,240 tons of carbon are recycled from agricultural product processing byproducts, 61,180 tons of carbon are fixed in crops in the planting industry, and 1,350 tons of biogas emissions are reduced in the livestock and poultry industry each year, achieving a coordinated carbon reduction of more than 70,000 tons in the three industries of "planting + breeding + processing", promoting the green and low-carbon coordinated development of livestock and poultry breeding, planting and processing industries, and providing a feasible solution for the realization of the national "dual carbon" strategic goals and the green and low-carbon development of the regional economy.

Claims

1. A system for the coordinated treatment of aquaculture manure, farmland drainage and processing waste, comprising a breeding farm (1), a planting field (2), a processing plant (3), a manure and urine separation device (4), a mixed anaerobic fermentation device (5), a closed anaerobic pond biogas fertilizer preparation device (6), a biogas power generation device (7), a breeding wastewater phosphorus recovery device (8), an artificial wetland (9), a reservoir pond (10) and a pond water reuse system (14), wherein the breeding farm is used for livestock and poultry breeding, the planting field is used for crop planting, the processing plant processes the crops in the planting field and the livestock and poultry in the breeding farm and produces distiller's grains; the manure and urine separation device separates the aquaculture manure generated by the breeding farm into solid manure and aquaculture wastewater mainly composed of urine; the artificial wetland and the reservoir pond are constructed between the planting field and the breeding farm, and the artificial wetland and the reservoir pond are connected; the system is characterized in that: The mixed anaerobic fermentation device ferments the mixture of solid feces produced by the feces-urine separation device and the wine dregs produced by the processing plant, and the biogas produced by the fermentation is passed through the biogas power generation device to generate electricity and / or is treated to generate natural gas for use by the processing plant. The closed anaerobic pond biogas preparation device performs anaerobically treatment on the solid-liquid mixture produced by the mixed anaerobic fermentation device to produce biogas residues and biogas liquids, and the produced biogas residues and biogas liquids are returned to the field after treatment; the aquaculture wastewater phosphorus recovery device uses the magnesium ammonium phosphate crystallization method and the hydroxy calcium phosphate crystallization method to remove phosphorus from the aquaculture wastewater produced by the feces-urine separation device, and the produced calcium hydroxy phosphate precursor and magnesium ammonium phosphate are returned to the field as fertilizers, and the produced wastewater is discharged into the artificial wetland; The drainage water from the planting fields is discharged into the artificial wetland through the ecological channel (15). The artificial wetland and reservoir remove COD, phosphorus and ammonia nitrogen from the drainage water from the planting fields and the waste liquid discharged from the phosphorus recovery device of the aquaculture wastewater. After treatment, the water in the reservoir is recharged to the farmland through the pond water reuse system or used as clean water for the aquaculture plant. The crops produced by the planting fields are used as feed for the aquaculture plant and raw materials for the processing plant. The by-products produced by the processing industry are used as fertilizers for planting troughs and feed for the aquaculture plant.

2. The system for coordinating the treatment of livestock manure, farmland drainage and processing waste according to claim 1 is characterized by: The matrix of the artificial wetland (9) contains coastal wetland sediments (13) rich in halophilic bacteria and anaerobic bacteria. An artificial floating island (11) and a photobioreactor (12) are arranged in the reservoir (10). Aquatic plants are planted on the artificial floating island, and the photobioreactor is a microalgae wall-attached photobioreactor.

3. The system for coordinating the treatment of livestock manure, farmland drainage and processing waste according to claim 1 or 2, characterized in that: The ecological channel (15) comprises a primary channel, an agricultural channel, a ditches, a branch channel and a main channel which are connected in sequence. Ecological slope protection (16) is arranged on both sides of the ecological channel. An ecological dam (17) and a vegetation filter belt are arranged in the ecological channel. Biochar-chitosan composite microspheres are arranged in the ecological slope protection.

4. A treatment method based on the coordinated treatment system for livestock manure, farmland drainage and processing waste according to claim 1, characterized in that: This is accomplished by following these steps: a). Solid-liquid separation of livestock and poultry manure; using a manure and urine separation device (4) to perform solid-liquid separation on livestock and poultry manure generated by a breeding farm (1), and to separate the livestock and poultry manure into solid manure and breeding wastewater mainly composed of urine, so as to subsequently treat the solid manure and breeding wastewater separately; b) Mixed anaerobic fermentation to produce gas; solid feces and distiller's grains produced by the processing plant are mixed in a mass ratio of 5:5 to 7:3, and after mixing, they are placed in a mixed anaerobic fermentation device (5) for anaerobic fermentation. The biogas produced by the fermentation is treated to form natural gas for use by the processing plant, and the biogas is passed through a biogas power generation device (7) to generate electricity for use by the processing plant; c). Phosphorus removal from aquaculture wastewater: The aquaculture wastewater generated by solid-liquid separation of livestock and poultry manure is dephosphorized by using the ammonium magnesium phosphate crystallization method and the hydroxy calcium phosphate crystallization method in the aquaculture wastewater phosphorus recovery device (8), and the precursor of the hydroxy calcium phosphate and the ammonium magnesium phosphate formed are returned to the field as fertilizers, and the generated wastewater is discharged into the artificial wetland (9) for further treatment; d). Preliminary treatment of farmland drainage water; in the process of flowing through the ecological channel (15), the farmland drainage water in the planting field flows through the primary channel, agricultural channel, ditches, branch channels and main channels in sequence, and is purified by the ecological slope protection (16), ecological dam (17) and vegetation filter belt in the ecological channel. The biochar-chitosan composite microspheres in the ecological slope protection, the plants and microorganisms in the ecological dam and the vegetation filter belt can effectively remove phosphorus and ammonia nitrogen in the farmland drainage water. The farmland drainage water treated by the ecological channel is discharged into the artificial wetland (9); e) Purification of water bodies in wetlands and reservoirs; when farmland drainage and aquaculture wastewater flow through artificial wetlands, the plants and microorganisms in the artificial wetlands consume COD, phosphorus and ammonia nitrogen in the water, thus achieving further treatment of the water body; after the water body in the artificial wetland flows into the reservoir (10), the microalgae on the inner wall of the photobioreactor and the aquatic plants on the artificial floating island further remove COD, phosphorus and ammonia nitrogen, so that the water quality in the reservoir reaches the quality that can be reused; f). Reservoir and pond water reuse: The pond water reuse system pumps water from the reservoir and pond to the planting fields to realize the re-injection of farmland water; the pond water reuse system pumps water from the reservoir and pond to the breeding farm as flushing water for livestock and poultry breeding sites; g). Recycling of materials and energy; the crops produced by the planting fields are used as feed for the breeding farms and raw materials for the processing plants, the livestock and poultry produced by the breeding farms provide processing raw materials for the processing plants, the accessories produced by the processing plants are used as fertilizers for the planting industry and feed for the breeding farms, and the wine grains produced by the processing plants are used as raw materials for mixed anaerobic fermentation and gas production, so as to realize the recycling of materials and energy between the breeding farms, planting fields and processing plants.

5. The method for treating livestock manure, farmland drainage and processing waste in a coordinated treatment system according to claim 4 is characterized in that: The phosphorus removal from aquaculture wastewater described in step c) is specifically achieved by the following steps: c-1). Preparing dolomite solution; preparing dolomite solution by the following steps: c-1-1). Crushing of dolomite: crushing the blocky dolomite with a crusher, passing the crushed dolomite through a 100-mesh sieve, and leaving the sieve under for later use; c-1-2) Acidification reaction of dolomite; first, a sufficient amount of the undersize dolomite obtained in step c-1-1) is taken and placed in a container, and 3.4 mL of hydrochloric acid having a mass concentration of 6 mol / L is added to 1 g of dolomite, and hydrochloric acid is added to the container, and the reaction is acidified at room temperature for 180 min to obtain a dolomite solution rich in calcium and magnesium ions; c-2). Phosphorus removal from aquaculture wastewater; Phosphorus removal from aquaculture wastewater is carried out through the following steps: c-2-1). Adjustment of pH value of aquaculture wastewater: First, adjust the pH value of aquaculture wastewater to pH=9 according to the initial pH value of aquaculture wastewater; c-2-2). Addition of dolomite solution; according to the dosage of Ca:P=1.67:1, add the corresponding amount of dolomite solution to the aquaculture wastewater; c-2-3) Phosphorus removal reaction; at room temperature, the reaction was stirred at a stirring speed of 200 r / min for 180 min to achieve effective phosphorus removal from aquaculture wastewater; c-2-4). After the phosphorus removal reaction is completed, the solution after the reaction is separated into solid and liquid. The precursor of calcium hydroxyphosphate and magnesium ammonium phosphate generated by the phosphorus removal reaction are returned to the field as fertilizer, and the liquid is discharged into the artificial wetland as aquaculture wastewater for further treatment.

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