KR102271699B1 - Apparatus for treating integrated anaerobic digestion of livestock excretions - Google Patents

Abstract

The present invention relates to an integrated digestion treatment system for livestock manure, a pretreatment unit for collecting, storing, and pretreating a mixed substrate, a thermal hydrolysis unit for solubilizing the mixed substrate by thermal hydrolysis, and decomposition of the mixed substrate in a single-phase digestion tank An anaerobic digestion unit that generates biogas from organic waste resources and digests it by microorganisms, a post-processing unit that stores the digestion filtrate and dehydrates the digestion filtrate into dehydration cake and desorption filtrate by centrifugation; It is characterized in that it comprises a wastewater treatment unit, a biogas purification unit for purification by removing impurities contained in biogas, and a biogas utilization unit utilizing the purified biogas. Therefore, in the present invention, it is possible to reduce the total nitrogen concentration flowing into the digester by more than 75% through dehydration of livestock manure and sewage residues in the substrate pretreatment process. By removing the effect on methanogenic bacteria in advance, it provides an effect that enables stable anaerobic digestion.

Description

Integrated digestion and treatment of livestock manure {APPARATUS FOR TREATING INTEGRATED ANAEROBIC DIGESTION OF LIVESTOCK EXCRETIONS}

The present invention relates to an integrated digestion treatment system for livestock manure, and more particularly, collects a plurality of organic waste resources including livestock manure for efficient integrated anaerobic digestion of food wastes including livestock manure and mixed substrates containing sewage residues. It relates to an integrated digestion and treatment system of livestock manure that performs an integrated digestion treatment.

Due to the rapid industrial development and improvement of living standards, the generation of organic waste resources such as livestock manure and food waste is on the rise. As of the end of 2017, the total amount of organic waste resources generated was 242,734 tons/day, of which 176,434 tons/day (72.7 %), manure 40,468 tons/day (16.7%), food waste 14,400 tons/day (5.9%), and sewage waste 11,432 tons/day (4.7%).

In particular, in the case of livestock excreta treatment, 67.5% of the total generated amount is composted, the public treatment rate is only 9.9%, and the anaerobic digestion rate is very insignificant. However, the government has recently promoted the integrated digestion policy of organic waste resources including livestock manure. As such, it is expected that the expanded distribution of the integrated livestock manure digestion project is

In addition, the previous organic waste resources showed various problems due to individual treatment, and most livestock excreta treatment facilities are private and individual treatment facilities, which have low treatment efficiency and act as odors and non-point pollution sources in public waters.

In the case of food waste treatment facilities, most of them are treated as feed and compost, and some anaerobic digestion facilities have insufficient utilization of production by-products, and their digestion efficiency is low at around 60%, making it difficult to treat them.

In addition, the operation rate of individual sewage waste anaerobic digestion facilities is as low as 70% or less, and the digestion efficiency is very low at 40% or less, so it is not able to exert anaerobic digestion function.

As such, the government is promoting the integrated organic waste digestion policy to solve the problems caused by individual treatment. The integrated fire extinguishing system selects foreign substances through pre-treatment of livestock manure, food waste, and sewage waste, and thermal hydrolysis and solubilization. It is homogenized through the integrated digestion.

In this way, the residue (dehydrated cake) generated during the integrated digestion process is converted to dry fuel to produce dry matter, and the produced dry matter is used as an auxiliary fuel for coal-fired power plants, or compost is produced through composting to supply and use to farms. The generated biogas is used to produce electricity through power generation or as an alternative heat source for LNG in dry fuel conversion facilities and composting facilities, thereby minimizing the use of fossil energy, and the digestion filtrate generated in the anaerobic digestion process is first treated and then discharged to a discharge or sewage treatment plant. It refers to a system in which the entire process to be linked is an integrated process.

As a characteristic of integrated digestion including livestock manure, anaerobic digestion is performed by mixing organic waste resources that can complement each other in order to reduce nutritional imbalance and inhibitory factors during anaerobic digestion that can be caused by individual characteristics of organic waste resources. This method has the advantage of increasing energy production and organic matter removal efficiency using organic waste resources and reducing the load associated with sewage treatment plants.

As most of the location of the integrated livestock excreta treatment facility is located in the sewage treatment plant, especially in winter, livestock manure and food waste are often brought in below 0℃ or in a frozen state. Since there is a situation where an unfulfilled condition may occur, it is necessary to solve the problem caused by the freezing of the substrate brought in outside in winter.

In addition, in the anaerobic digestion process, protein degradation is the most difficult, and it is decomposed in the order of fat and carbohydrate. In general, it is known that during anaerobic digestion, the protein degradation rate is within 10%, the fat degradation rate is 50%, and the carbohydrate degradation rate is about 70%.

Looking at the components of each substrate, livestock manure has the highest protein (42%), sewage waste also has the highest protein (41%), and carbohydrates make up 46% of food waste. In the case of integrated digestion of food waste including livestock manure and sewage residues having different decomposition rates, it is practically difficult to maintain a stable organic matter decomposition rate when a general anaerobic digestion process is applied.

_{In addition, during the integrated digestion of livestock manure, the high ammonia nitrogen (NH 4} ⁺ -N) concentration is high in the anaerobic digestion tank due to the effect of the high concentration of total nitrogen (TN) contained in livestock manure, sewage residue, and food waste. It has been proven that it has an inhibitory effect on the methane formation of methanogens in the anaerobic digester, so even though the ammonia nitrogen concentration should be maintained below 1,500 mg/L, the total nitrogen concentration contained in the substrate is fundamentally high, so livestock manure integration During digestion, the ammonia nitrogen concentration in the digester is high, making it difficult to smoothly operate the anaerobic digester.

[Table 1] Integrated Digestive Substrate Component Composition and Nitrogen Concentration

Republic of Korea Patent No. 10-1313766 (October 01, 2013) Republic of Korea Patent Registration No. 10-1309422 (September 24, 2013) Republic of Korea Patent Registration No. 10-1631835 (June 20, 2016)

The present invention was devised to solve the conventional problems as described above, and to solve the problem of winter freezing of livestock manure and food waste brought in from the outside, steam is supplied to each storage tank to integrate livestock manure through smooth pretreatment Its purpose is to provide digestive technology.

In addition, the present invention provides livestock manure and sewage waste through solid-liquid separation in order to suppress the toxic action of methanogenic bacteria in the digester due to the high-concentration nitrogen content contained in the livestock manure, food waste, and sewage residue substrates. The purpose of this is to provide stable livestock manure integrated digestion technology through efficient pretreatment by homogeneously mixing with food waste pretreatment substrate.

In addition, the present invention maximizes the amount of biogas generated by more than 10% compared to the existing technology through thermal hydrolysis and anaerobic digestion of the pre-treated livestock manure integrated substrate, and the generated digestion filtrate is solid-liquid separation through solid dehydrated cake to dry fuel or The purpose is to provide an integrated livestock manure digestion technology that recycles by-products through composting.

In addition, the present invention provides a livestock manure integrated digestion technology that uses biogas generated in the anaerobic digestion process to produce and sell electricity through power generation as an alternative fuel to LNG through refining, or to supply steam to a boiler. There is a purpose.

The present invention for achieving the above object includes: a pre-processing unit 100 for collecting and storing a mixed substrate including livestock manure, food waste, and sewage residue to pre-treat the mixed substrate, respectively; a thermal hydrolysis unit 200 installed downstream of the pretreatment unit 100 to solubilize the pretreated mixed substrate by thermal hydrolysis; anaerobic digestion unit 300 installed downstream of the thermal hydrolysis unit 200 to decompose the mixed substrate in a single-phase digestion tank to generate biogas from organic waste resources and digest by microorganisms; a post-processing unit 400 for storing the digestion filtrate after decomposition of organic waste resources through the anaerobic digestion unit 300 is completed, and dehydrating the digestion filtrate into a dehydrated cake and a desorption filtrate by centrifugation; a wastewater treatment unit 500 for treating the desorption filtrate separated in the post-treatment unit 400; a biogas purification unit 600 for refining and removing impurities contained in the biogas generated in the anaerobic digestion unit 300; and a biogas utilization unit 700 that utilizes the biogas purified by the biogas purification unit 600 .

The pre-processing unit 100 of the present invention includes: livestock manure pre-treatment means for pre-processing livestock manure; food pretreatment means for pretreating food waste; sewage residue pre-treatment means for pre-treating sewage residue; and an intermediate storage tank for storing the pre-treated livestock manure, food waste, and sewage waste.

The livestock manure pretreatment means of the present invention comprises: a livestock manure storage tank for storing livestock manure while heating it by steam; It is installed downstream of the livestock excreta storage tank, a contaminant comprehensive treatment for removing foreign substances from the stored livestock manure; a centrifugal dehydrator installed downstream of the contaminant comprehensive treatment machine to separate the livestock manure from which the foreign matter has been removed into solid and liquid and discharge the solid phase to the intermediate storage tank; and a wastewater treatment facility installed downstream of the centrifugal dehydrator to treat the separated liquid phase.

The food pretreatment means of the present invention includes: a food storage tank for storing food waste while heating it with steam; a crushing separator installed downstream of the food storage tank to crush the stored food waste to sort foreign substances; a pulper that is installed downstream of the crusher and finely crushes food waste and sorts foreign substances; a drum screen installed downstream of the pulper to sort out foreign substances to uniform particles of food waste; and a cyclone installed downstream of the drum screen to separate and remove fine foreign substances in the food waste to a lower portion.

The sewage residue pretreatment means of the present invention includes: a sewage residue storage tank for storing the sewage residue; a drum screen installed downstream of the sewage residue storage tank to select foreign substances from the stored sewage residue; a centrifugal dehydrator installed downstream of the drum screen to separate solid-liquid sewage residues from which the foreign substances are removed and discharge the solid phase to the intermediate storage tank; and a wastewater treatment facility installed downstream of the centrifugal dehydrator to treat the separated liquid phase.

The thermal hydrolysis unit 200 of the present invention includes: a manufacturing tank for preheating the organic waste resources pretreated in the pretreatment unit 100 by recovering waste heat generated after the reaction of high temperature and high pressure steam; a reaction tank receiving high-temperature and high-pressure steam to first destroy and solubilize cell walls of organic waste resources homogenized in the production tank; a storage tank for solubilizing the cell wall of the organic waste resource in which the cell wall is primarily destroyed by pressure transfer from the reaction tank to the organic waste resource whose cell wall is primarily destroyed by pressure expansion through pressure drop; a primary cooler for supplying cooling water from sewage treatment plant effluent to organic waste resources whose cell walls are secondarily destroyed in the storage tank for primary cooling to a temperature of 80°C to 85°C; and a secondary cooler for supplying cooling water to a double-tube heat exchanger to secondary-cool the primary cooled organic waste resource to a temperature of approximately 35°C to 40°C.

The anaerobic digestion unit 300 of the present invention, a scum remover for removing foreign substances in the upper part, a cyclone for removing foreign substances in the lower part, a digester overflow induction facility, and complete mixing and agitation in the digester It is characterized in that it consists of a vertical vertical shaft type mechanical agitator and a single-phase digester including a baffle.

The post-processing unit 400 of the present invention includes: a digestion filtrate storage tank for temporarily storing the digestion filtrate generated in the anaerobic digestion unit 300; a centrifugal dehydrator installed downstream of the digestion filtrate storage tank to separate the stored digestion filtrate into solid and liquid; a dry fuel facility for producing dried products using the solid dewatering cake separated in the centrifugal dehydrator and using it as auxiliary fuel for a coal-fired power plant; and a composting facility for producing compost and supplying it to farms using the solid dehydrated cake separated in the centrifugal dehydrator.

The biogas purification unit 600 of the present invention includes: a water trap that primarily removes moisture in the biogas by a swirling flow method; a chiller installed downstream of the water trap to secondarily remove moisture through cooling; a dry desulfurization facility installed downstream of the chiller to remove hydrogen sulfide contained in biogas; a siloxane removal facility that removes siloxane in biogas using the adsorption function of activated carbon; a primary gas filter installed at the rear end of the siloxane removal facility to thirdly remove moisture in biogas; a gas storage tank for temporarily storing biogas from which moisture, hydrogen sulfide and siloxane have been removed; and a secondary gas filter that removes moisture fourthly before utilizing the biogas temporarily stored in the gas storage tank.

The biogas utilization unit 700 of the present invention includes: a biogas power generation facility that generates and sells electricity by generating electricity from biogas from which moisture, hydrogen sulfide, and siloxane have been removed from the biogas purification unit 600 as fuel; a waste heat boiler for producing steam using waste heat generated in the power generation process of the biogas power plant and supplying it as a heat source to the pre-processing unit 100 and the thermal hydrolysis unit 200; and a co-fired boiler for producing steam using biogas from which moisture, hydrogen sulfide, and siloxane have been removed in the biogas purification unit 600 as a fuel and supplying it as a heat source to the pre-processing unit 100 and the thermal hydrolysis unit 200; characterized by including.

As described above, in the present invention, it is possible to reduce the total nitrogen concentration flowing into the digester by 75% or more through dehydration of livestock manure and sewage residue in the substrate pretreatment process. It provides an effect capable of stable anaerobic digestion by removing in advance the effect on anaerobic digestion methanogens due to ammonia toxicity.

The present invention removes foreign substances through crushing and screening for each substrate, and it is possible to derive optimal conditions for anaerobic digestion through high-temperature and high-pressure thermal hydrolysis solubilization, so it provides the effect of increasing the amount of biogas generated by 10% or more compared to the existing technology.

The present invention provides the effect of minimizing the area of the business site because it is possible to configure a single-phase digestion tank compared to the two-phase anaerobic digestion technology of the existing technology.

The present invention provides the effect of ensuring the economic feasibility of the facility through zero fossil fuel and energy independence since the produced biogas can be used as an alternative fuel for power generation or LNG after refining.

According to the dual configuration of the waste heat boiler and the co-fired boiler, the facility can be operated even during boiler failure or periodic inspection, so that the entire system can be operated without interruption, thereby maximizing the throughput of the input substrate.

1 is a block diagram showing an integrated digestion treatment apparatus for livestock manure according to an embodiment of the present invention.

Hereinafter, a preferred embodiment of the present invention will be described in more detail with reference to the accompanying drawings.

1 is a block diagram showing an integrated digestion treatment apparatus for livestock manure according to an embodiment of the present invention.

As shown in FIG. 1, the integrated digestion treatment apparatus of livestock manure according to this embodiment includes a pretreatment unit 100, a thermal hydrolysis unit 200, an anaerobic digestion unit 300, a post-treatment unit 400, a wastewater treatment unit ( 500), a biogas purification unit 600 and a biogas utilization unit 700, for efficient integrated anaerobic digestion of food wastes including livestock manure and mixed substrates including sewage residues, including livestock manure. It is an integrated digestion and treatment system for livestock manure that collects organic waste resources and performs integrated digestion treatment.

The pre-processing unit 100 is a pre-processing means for pre-processing the mixed substrate by collecting and storing the mixed substrate including livestock manure, food waste, and sewage residue, and crushes the imported livestock manure, food waste, and foreign substances contained in the livestock manure. A livestock manure pretreatment means for pretreating livestock manure by homogenizing the mixed substrate through , sorting, etc., a food pretreatment means for pretreating food waste, a sewage waste pretreatment means for pretreating sewage waste, and pretreated livestock manure and food waste and an intermediate storage tank 140 for storing sewage residues.

In addition, the pre-processing unit 100 reduces the nitrogen concentration through the process of removing foreign substances contained in the substrate and dehydration through crushing and sorting for maintaining the optimal conditions for thermal hydrolysis and integrated digestion for imported livestock manure, food waste, and sewage residue process simultaneously.

The livestock manure pretreatment means is a pretreatment means for pretreating livestock manure, and consists of a livestock manure storage tank 111 , a contaminant comprehensive treatment machine 112 , a centrifugal dehydrator 113 , and a wastewater treatment facility 114 .

The livestock manure storage tank 111 is a storage tank that stores livestock manure while heating it by steam, and the imported livestock manure is temporarily stored in the livestock manure storage tank 111 including a heating device using steam.

In particular, the pre-processing unit 100 is stored in the livestock manure storage tank 111 when the organic waste resource is livestock manure, and the livestock manure storage tank consists of at least two stages, and the storage capacity of each stage is at least 2 days or more. In case of this periodic inspection, a malfunction of the transfer pump or cleaning of the storage tank, a bulkhead is installed between the stage and the stage so that livestock manure can be stored in the second stage. At the top of the bulkhead, when the first stage reaches the full water level, 2 It is preferable to configure it in a weir shape that can overflow in stages.

In addition, the livestock manure storage tank 111 installs steam pipes in all directions to prevent freezing and thawing of livestock manure brought in frozen in winter and freezing in the storage tank, and the steam is supplied from a waste heat boiler using power generation waste heat or a co-fired boiler using biogas. Of course, it is also possible to use it.

The contaminant comprehensive treatment machine 112 is installed downstream of the livestock manure storage tank 111 to remove foreign substances from the livestock manure stored in the livestock manure storage tank 111, and the livestock manure brought into the livestock manure storage tank is a contaminant comprehensive treatment machine ( 112) removes foreign substances such as sand, rice husk, livestock hair bundles, syringes, etc. contained in livestock manure, and the removal particle diameter is 1 mm or less and consists of a screen and sediment removal equipment to remove foreign substances and sediments such as sand contained in livestock manure. can be removed at the same time.

The centrifugal dehydrator 113 is installed downstream of the contaminant comprehensive treatment machine 112 to separate the livestock manure from which foreign substances have been removed from the contaminant comprehensive treatment machine 112 in solid-liquid separation and discharge the solid phase to the intermediate storage tank 140. It is a separation means.

In this way, the livestock manure from which foreign substances are removed through the contaminant treatment unit 112 is separated into solid and liquid through a centrifugal dehydrator 113, and in this process, the total nitrogen (TN) concentration of 5,000 mg/L is 75 in the solid phase (dehydrated cake). 1,250mg/L from which % has been removed is added to the thermal hydrolysis facility, thereby preventing inhibition of anaerobic digestion due to the toxicity of methanogenic bacteria due to high nitrogen concentration in the anaerobic digestion process.

The wastewater treatment facility 114 is installed downstream of the centrifugal dehydrator 113 and treats the liquid phase separated from the centrifugal dehydrator 113. The liquid phase separated from the solid-liquid in the centrifugal dehydrator 113 is linked to the wastewater treatment facility. will be processed

Therefore, livestock manure is separated from solid and liquid through the centrifugal dehydrator 113 by means of pretreatment of livestock manure, and the solid phase (cake) is used as a substrate for anaerobic digestion, thereby reducing ammonia toxicity during anaerobic digestion (substrate input is stopped when more than 3,000mg/L) In order to prevent in advance, the pretreatment process of maintaining the ammonia concentration of the livestock manure integrated digestion substrate below 1,500mg/L is performed.

The food pretreatment means is a pretreatment means for pretreating food waste, and includes a food storage tank 121 , a crusher separator 122 , a pulper 123 , a drum screen 124 , and a cyclone 125 .

The food storage tank 121 is a storage tank that stores food waste while heating it by steam. The food waste is a food storage tank 121 including a heating device using steam and a perforated network for smooth drain of food wastewater. temporarily detained in

In particular, the preprocessor 100 is stored in the food storage tank 11 when the organic waste resource is food waste, and the food storage tank is installed with a steel frame, and the inner surface in contact with food is STS 304 or higher in consideration of corrosion caused by low pH of the substrate. The storage capacity should be at least 3 days or more.

In addition, two or more double screw type transfer devices are installed in the lower part of the food storage tank 121 so that even when one double screw is not in operation due to foreign substances, the other double screw operates to separate the food into the shredding and sorting machine at the rear end. It has a structure that can be transferred to 122, and in particular, since the moisture content of food is about 80%, moisture (food wastewater) is separated from the food stored in the food storage tank and transferred to the intermediate storage tank 140 through the perforated network at the bottom of the storage tank.

The lower perforated network of the food storage tank 121 is 20 cm apart and has a diameter of 5 mm. It is installed in a zigzag form at the lower end of the double screw, so that the moisture contained in the food is smoothly separated, so that when the double screw is operated, the food can be easily transferred to the shredding separator at the rear end of the storage tank. structure that can be

The crushing separator 122 is a separator installed downstream of the food storage tank 121 to crush the food waste stored in the food storage tank 121 to separate foreign substances, and the pulper 123 is a It is installed downstream and is a sorting means for secondarily finely shredding food waste from which foreign substances have been selectively removed by the shredding and sorting machine 122, and for sorting and removing secondary foreign substances.

The drum screen 124 is installed downstream of the pulper 123 and is a sorting means for sorting foreign substances to uniform particles of food waste processed in the pulper 123, and removes foreign substances to uniformly reduce particles of food waste to 3 mm or less. will be selected

The cyclone 125 is installed downstream of the drum screen 124 and is a separation means for separating and removing fine foreign substances in the food wastes selected by the drum screen 124 to the lower part and discharging them to the intermediate storage tank 140 .

Therefore, more than 97% of foreign substances are removed from the food waste through the crusher 122, the pulper 123, the drum screen 124, and the cyclone 125, and the particle size is uniformly pre-treated to 3 mm or less. 140) is transferred.

The sewage residue pre-treatment means is a pre-treatment means for pre-treating sewage residues, and consists of a sewage residue storage tank 131 , a drum screen 132 , a centrifugal dehydrator 133 , and a wastewater treatment facility 134 .

The sewage residue storage tank 131 is a storage tank for storing sewage residues, and in particular, the pre-processing unit 100 is stored in the sewage residue storage tank 131 when the organic waste resource is sewage residue, and the sewage residue storage tank consists of at least two stages or more. The storage capacity of each stage is at least 2 days, and a bulkhead is installed between the stage and the stage so that the second stage can store sewage waste even when the first stage performs periodic inspection, transfer pump failure, or storage tank cleaning. The upper part of the bulkhead is constructed in the shape of a weir that can overflow to the second stage when the first stage reaches the full water level.

The drum screen 132 is installed downstream of the sewage residue storage tank 131 and is a sorting means for sorting foreign substances from the sewage residue stored in the sewage residue storage tank 131. The sewage residue carried into the sewage residue storage tank 131 is a drum. The screen 132 removes hair, skeins, etc., which are foreign substances contained in the sewage residue, and the particle diameter of the drum screen 132 is 1 mm. Through the removal of foreign substances such as hair, the anaerobic digestion process and the post-treatment unit 400 dry fuel facility It is possible to prevent in advance the deterioration of quality and processing efficiency due to foreign substances entering the composting facility.

The centrifugal dehydrator 133 is installed downstream of the drum screen 132 to separate solid and liquid sewage residues from which foreign substances have been removed from the drum screen 132 and discharge the solid phase to the intermediate storage tank 140, the drum screen ( 132) and the foreign substances are removed, the sewage residue is separated into solid-liquid through the centrifugal dehydrator 133. In this process, the total nitrogen (TN) concentration of 3,000mg/L of the sewage residue is dehydrated and the solid phase (dehydrated cake) is 75 % is removed at 750mg/L and it is put into the hydrolysis facility, and accordingly, it is possible to prevent inhibition of anaerobic digestion due to the toxicity of methanogenic bacteria due to high nitrogen concentration in the anaerobic digestion process.

The wastewater treatment facility 134 is installed downstream of the centrifugal dehydrator 133 to treat the liquid phase separated from the centrifugal dehydrator 133 . The liquid phase separated from the solid-liquid in the centrifugal dehydrator 133 is a wastewater treatment facility 134 . ) will be linked.

Therefore, the sewage residues are separated from solids and liquids through the centrifugal dehydrator 133 by the sewage residues pretreatment means, and then the solid phase is used as the target substrate for anaerobic digestion, thereby preventing ammonia toxicity during anaerobic digestion (stop adding the substrate when the amount exceeds 3,000mg/L) in advance. In order to prevent this, a pre-treatment process is performed to maintain the ammonia concentration of the livestock manure integrated digestion substrate below 1,500 mg/L.

The intermediate storage tank 140 is a storage tank for temporarily storing livestock manure, food waste, and sewage waste pretreated by the pretreatment means. A vertical vertical shaft type mechanical stirrer is installed on the upper part of the tank to maintain a uniform concentration and prevent the occurrence of sediment.

In addition, the intermediate storage tank 140 is composed of two stages, and the storage capacity of each stage is at least 1.5 days. Even when the first stage performs periodic inspections, transfer pump failure, or storage tank cleaning, the mixed substrate pretreated in the second stage It is preferable to install a partition wall between the tiers to store the water, and to configure the upper part of the bulkhead in a weir shape that can overflow into the second tier when the first tier reaches the full water level.

This pretreatment unit 100 supplies steam in the form of a double jacket to each storage tank for efficient pretreatment of the substrate brought in in the frozen state of livestock manure and food waste in winter, and the high concentration total nitrogen (TN) content contained in the substrate In order to lower the level, it is desirable to separate the livestock manure and sewage waste through a centrifugal dehydrator to solid-liquid and adopt only the solid phase (cake) as an anaerobic digestion substrate.

The thermal hydrolysis unit 200 is installed downstream of the pretreatment unit 100 and is a thermal hydrolysis means for solubilizing the mixed substrate pretreated in the pretreatment unit 100 by thermal hydrolysis, and preheats the pretreated integrated substrate, By supplying steam to the preheated integrated substrate, it maximizes the amount of water-soluble organic substances (VDS, Volatile Dissolved Solid) through deriving the optimal conditions for the anaerobic digester, and controls the temperature of the integrated substrate to 39~40℃ through a two-stage cooling system. It consists of a tank 210 , a reaction tank 220 , a storage tank 230 , a primary cooler 240 , and a secondary cooler 250 .

The thermal hydrolysis unit 110 supplies the organic waste resources temporarily stored in the intermediate storage tank 140 to the thermal hydrolysis device by operating the mono pump after pretreatment suitable for the characteristics of each substrate in the pretreatment unit 100 to provide high-temperature, high-pressure As solubilization proceeds according to steam injection, the ratio of VDS (Volatile Disolved Solid), which is the optimal condition for anaerobic digestion, increases more than three times.

The manufacturing tank 210 is a manufacturing means for preheating the organic waste resources pretreated in the pretreatment unit 100 by recovering waste heat generated after the reaction of high temperature and high pressure steam. The organic waste material at 25℃ is preheated to 95~100℃.

The production tank 210 collects waste heat generated after the reaction of the high-temperature and high-pressure steam injected into the reaction tank 220 when the organic waste resource is solubilized in the reaction tank 220 and the storage tank 230, and a pretreatment unit ( 100), the pre-treated organic waste material is preheated.

In addition, the production tank 210 can be homogenized by mixing the organic waste resources up and down in a manner that the organic waste resources are drawn from the lower part and circulated to the upper part through the mono pump at the same time as the preheating of the organic waste resources. Here, it is of course possible to use a rotating positive displacement metering pump as a uniaxial eccentric screw spiral pump as the monopump.

The reaction tank 220 is a reaction means for solubilizing by first destroying the cell wall of the organic waste material homogenized in the production tank 210 by receiving high-temperature and high-pressure steam, and the steam is at a high temperature of 180-200° C., 10-12 bar. And it is produced and supplied in a waste heat boiler or a mixed-fired boiler under high pressure conditions.

In the reaction tank 220, it is possible to primarily destroy the cell walls of the organic waste resources homogenized in the production tank 210 by receiving the high-temperature and high-pressure steam produced from the waste heat boiler or the co-fired boiler.

In addition, when the waste heat boiler of the biogas utilization unit 700 is normally operated, the reaction tank 220 receives the steam produced in the waste heat boiler as a heat source by using the waste heat generated from the biogas power generation facility as a heat source, digesting gas power generation facility or waste heat If the boiler is unable to operate normally due to a malfunction or regular inspection, it is possible to receive steam generated from a mixed-fired boiler that uses biogas and LNG as a combined fuel.

As the primary solubilization proceeds according to the injection of high-temperature and high-pressure steam in the reaction tank 220 and the secondary solubilization is performed according to the pressure drop in the storage tank 24, VDS (Volatile Solid) among VS (Volatile Solid) which can be said to be an indicator of the solubilization rate It can be confirmed through the experimental examples in [Table 2] below that the (Volatile Dissolved Solid) ratio increases about 3 times, and the SCOD (Soluble Chemical Oxygen Demand) ratio of TCOD (Total Chemical Oxygen Demand) increases by about 2 times or more.

The storage tank 230 pressure-transports the organic waste resource whose cell wall is primarily destroyed in the reaction tank 220, and the cell wall of the organic waste resource whose cell wall is primarily destroyed according to pressure expansion through pressure drop is secondarily destroyed. It is a solubilizing treatment means.

The storage tank 230 pressure-transfers the organic waste resource whose cell wall is primarily destroyed in the reaction tank 220 to secondary destruction of the cell wall of the organic waste resource whose cell wall is primarily destroyed according to pressure expansion through pressure drop. can

That is, the storage tank 230 is formed to have a pressure of 0.5 bar or less so that the pressure automatically drops when the organic waste resource whose cell wall is primarily destroyed is moved in the reaction tank 220 having a pressure of 6 bar, Secondary solubilization proceeds by secondly destroying the cell wall of organic waste resources without a separate device.

The primary cooler 240 is a cooling means for supplying cooling water from the sewage treatment plant effluent to the organic waste resource whose cell wall has been secondaryly destroyed in the storage tank 230 and cooling it primarily to a temperature of 80°C to 85°C.

This primary cooler 240 supplies cooling water corresponding to sewage treatment plant effluent to an organic waste resource having about 110° C. in which the cell wall is secondarily destroyed in the storage tank 230 , that is, thermally hydrolyzed organic waste resource. It can be first cooled to have a temperature of -85 ℃.

The secondary cooler 250 is a cooling means for supplying cooling water to a double-tube heat exchanger to secondary-cool the organic waste material cooled primarily to a temperature of approximately 35°C to 40°C. By supplying the organic waste material having a temperature of about 80 to 85 ℃ which has been primarily cooled in the primary cooler 240 may be secondary cooled to have a temperature of about 40 ℃.

As such, the reason for cooling the temperature of the livestock manure integrated digestion solubilization substrate to 39-40 ℃ through the primary cooler 240 and the secondary cooler 250 in the thermal hydrolysis unit 200 is mesophilic methanogen. This is because the rate of decomposition of organic matter is highest at 40 ° C., and the activity of microorganisms is rapidly reduced at 40 ° C. or higher, and the rate of decomposing organic matter from the substrate is reduced, thereby reducing the amount of biogas generated.

Accordingly, the present invention can increase the decomposition rate of organic matter using methanogenic bacteria by cooling the organic waste resource to 39 to 40 ℃ before inputting the organic waste resource to the anaerobic digestion unit 300 .

Therefore, the substrate on which the pretreatment is completed passes through the preparation tank 210, the reaction tank 220, and the storage tank 230, and then cell wall destruction and cell polymer dissolution proceed using high-temperature and high-pressure steam, and then the primary cooler 240. And through the secondary cooler 250, the thermal hydrolysis process of lowering the temperature of the substrate to 35 ~ 40 ℃ is made.

The thermal hydrolysis unit 200 produces and utilizes steam by utilizing power generation waste heat or biogas, and solubilization proceeds through a manufacturing tank, a reaction tank, and a storage tank, thereby maximally increasing the amount of water-soluble organic substances ((VS (Volatile Solid)) Medium VDS (Volatile Dissolved Solid) amount is increased), and the solubilized substrate preferably includes a 1.2-second cooler to maintain a digester inflow TS (Total Solid) concentration of 10%, and a temperature of 39-40 ℃.

The anaerobic digestion unit 300 is installed downstream of the thermal hydrolysis unit 200 to decompose the mixed substrate in the single-phase digestion tank 310 to generate biogas from organic waste resources and digest by microorganisms. As an anaerobic digestion means, heat The substrate solubilized through hydrolysis is anaerobically digested in a single-phase digestion tank with an organic material loading rate of 2.0 to 2.5 kgVS/m ^{3 .d.}

The anaerobic digestion unit 300 includes a scum remover for removing foreign substances from the upper part, a cyclone for removing foreign substances from the lower part, a digester overflow induction facility, and a vertical input for complete mixing and agitation in the digester. Of course, it is also possible that the single-phase digestion tank 310 including a axial mechanical stirrer and a baffle is possible.

Therefore, the anaerobic digestion unit 300 includes a mechanical vertical vertical stirrer and a baffle for complete mixing of the input substrate, a scum removal device and a cyclone and digester overflow inducing device, which is a device for removing foreign substances from the upper and lower parts of the digester, _{Equipment for stable operation of digesters such as iron salt (FeCl 3} ) injection equipment for primary hydrogen sulfide removal in biogas and substrate input organic matter load rate is 2.0-2.5 kgVS/m ³ .d, TS concentration of 10% or less. it is preferable

The anaerobic digestion unit 300 is solubilized from the thermal hydrolysis unit 200, the VDS/VS ratio is 3 times, the SCOD/TCOD ratio is 2 times or more, the solubilized substrate is 39-40 from the primary cooler and the secondary cooler It is cooled to ℃, and at this time, the TS (Total Solids) concentration of the solubilized substrate is 10% or less, and the organic loading rate (OLR) is introduced into the digester in a state of 2.0 to 2.5, thereby providing an optimal habitat environment for methanogens. A medium-temperature digestion method that can efficiently and stably decompose organic matter from organic waste sources for livestock manure is adopted, and it is a single-phase single-phase digestion tank 310 that does not require a separate acid fermentation tank.

In addition, the single-phase digestion tank 310 is preferably provided with the following device for efficient and stable processing of the thermally hydrolyzed substrate. Organic waste resources for livestock excreta usually contain 25-35% of inorganic substances (FS, Fixed Solids), and 1-2% of oil contained in food waste. Red pepper powder, sesame, fiber, etc.) is not removed, so these unremoved FS components, oil, and foreign substances are put into the digester and float in the lower part of the digester or float on the upper part to form scum, so floating on the upper part of the digester Foreign matter is removed by installing a scum removal device.

The scum removal device transfers and processes the upper floating foreign substances to the digestion filtrate storage tank 410 according to the operation of the pump in a state immersed in the water level with the upper part of the cylindrical pipe removed according to the water level at the upper part of the digester.

At this time, the operation of the pump operates for 5 minutes per hour. Digester dredging period by installing a cyclone to install a cyclone for foreign substances that settle in the lower part of the digester, and transferring and processing solid foreign substances to the digestion filtrate storage tank 410 through solid-liquid separation in the cyclone, and returning liquid microorganisms and organic substances to the digester can be extended by more than 15 years compared to the existing technology, so that the operation of the single-phase fire extinguisher 310 can be used semi-permanently.

In addition, the single-phase digester 310 is equipped with an overflow prevention facility that can cope with an abnormal situation in the digester, and when an anaerobic microbial abnormal situation occurs in the digester, a large amount of toxic substance is injected in the digester. It is installed in order to prevent a phenomenon in which the biogas purification unit 600 is leaked from the rear stage to contaminate the biogas purification unit 600 and thus the entire facility operation is stopped.

In addition, in the single-phase digestion tank 310, a vertical vertical mechanical stirrer and 3-4 baffles are installed at the lower end of the digester for complete mixing of the incoming solubilized substrate. As the solubilized substrate is completely mixed, the organic material is decomposed by the smooth contact between the methanogenic bacteria and the solubilized substrate, and the biogas generated in the organic material decomposition process can be increased by more than 10% compared to the existing technology.

The post-processing unit 400 stores the digestion filtrate after decomposition of organic waste resources is completed through the anaerobic digestion unit 300, and dehydrates the digestion filtrate into a dehydrated cake and a desorption filtrate by centrifugation. As a post-treatment means, The digestion filtrate generated in the anaerobic digestion unit uses the dehydrated cake generated through dehydration to produce and use by-products through dry fuel or composting, and the digestion filtrate storage tank 410, centrifugal dehydrator 420, dry fuel conversion facility 430, composting It consists of facilities 440 .

This post-processing unit 400 stores the digested digestion residues, separates the solids and liquids in the digestion residues through dehydration, and utilizes the dehydrated cake, which is a solid product, to dry fuel or compost It is a facility that utilizes by-products produced.

The digestion filtrate storage tank 410 is a storage means for temporarily storing the digestion filtrate generated in the anaerobic digestion unit 300, and the thermal hydrolysis solubilized substrate input from the single-phase digestion tank 310 of the anaerobic digestion unit 300 is an organic material loading rate. Under the conditions of 2.0-2.5 kgVS/m ³ .d and a residence time of 22-25 days, more than 60% of organic matter is decomposed, and the digestion residues that have been decomposed are transferred to the digestion filtrate storage tank 410 of the post-processing unit 400 .

The digestion filtrate storage tank 410 is configured in two stages for 3 days or more, and has a structure that can store the digestion residues normally even when cleaning the first stage, and the stirring type is maintained to be completely mixed using a vertical vertical shaft type mechanical stirrer.

The centrifugal dehydrator 420 is installed downstream of the digestion filtrate storage tank 410 and is a separation means for solid-liquid separation of the digestion filtrate stored in the digestion filtrate storage tank 410. A centrifugal dehydrator installed at the rear end of the digestion filtrate storage tank 410 In (20), the digestion residues are separated into solid and liquid, and the moisture content of the dehydrated cake, which is a solid, can be maintained at 68 to 70%.

When general anaerobic digestion is applied, the moisture content of the dehydrated cake of digestion residues is around 80%. The decomposition rate is high, the decomposition time of organic matter is very short, and the moisture content of the dehydrated cake can be kept low because the dehydration property is greatly improved.

In addition, despite changes in the concentration of substrates such as food waste and sewage residues according to the season, the substrate can be unified through thermal treatment and the concentration can also be maintained uniformly. , when considering the thermal hydrolysis single-phase digestion technology of the present invention, since a constant concentration of the digestion filtrate is maintained throughout the year, there is no need to change the amount of chemical according to the season during dehydration, which is very convenient in operation.

The dry fuel conversion facility 430 is a dry fuel conversion means that uses the solid dehydration cake separated in the centrifugal dehydrator 420 to produce a dried product and use it as an auxiliary fuel for a coal-fired power plant, and the dehydration cake generated through the centrifugal dehydrator 420 . (Moisture content 68-70%) is dried to a moisture content of 10% or less through drying in a dry fuel conversion facility 430, and the dried product is used as an auxiliary fuel for a coal-fired power plant, and the dry heat source of the dry fuel conversion facility is a single-phase digester (310) By using the biogas produced in Korea, it can replace LNG, which is a fossil fuel, and contribute to reducing the operating cost of the facility.

The composting facility 440 is a composting means for producing and supplying compost to farms using the solid dehydrated cake separated in the centrifugal dehydrator 420. The dehydrated cake generated through the centrifugal dehydrator 420 is a composting facility 440. The compost can be produced and supplied to farms, and the hot air supplied to the composting facility uses the biogas produced in the single-phase digester.

The post-processing unit 400 uses the dehydrated cake generated through dehydration of the digestion filtrate generated in the anaerobic digestion unit 300 as an auxiliary fuel for a coal-fired power plant by producing a dried product at a dry fuel facility, or composting through a composting facility. It is more preferable to include what is produced and utilized by the farm.

The wastewater treatment unit 500 is installed downstream of the post-treatment unit 400 and is a wastewater treatment means for treating the desorption filtrate separated from the post-treatment unit 400, and the desorption filtrate is treated as wastewater and discharged or treated in connection with a sewage treatment plant. It consists of a wastewater treatment facility (510).

The biogas purification unit 600 is a biogas purification means for removing impurities contained in the biogas generated by the anaerobic digestion unit 300 for purification, and the biogas generated through the anaerobic digestion unit 300 is water. , siloxane and hydrogen sulfide are removed to remove impurities, and a water trap (610), a chiller (620; chiller), a dry desulfurization facility (630), a siloxane removal facility (640), a primary gas filter (650), It consists of a gas storage tank 660 and a secondary gas filter 670 .

A water trap (610; water trap) is a removal means for primarily removing moisture in the biogas by a swirling flow method, and by introducing the biogas containing moisture into the upper part of the water trap, a high-speed centrifugal force inside the water trap A vortex flow is formed by this, and moisture is primarily removed due to the specific gravity difference between moisture and biogas.

A chiller 620 is installed downstream of the water trap 610 and is a removal means for secondarily removing moisture from the water trap 610 through cooling, and cooling the firstly removed moisture. 99.5% or more of moisture is removed secondarily through

The dry desulfurization facility 630 is installed downstream of the chiller 620 as a desulfurization means for removing hydrogen sulfide contained in biogas, and iron salt (FeCl ₃ ) in the primary single-phase digester for removing hydrogen sulfide contained in biogas. A secondary dry desulfurization facility 630 is provided together with the injection facility.

The siloxane removal facility 640 is a removal means for removing siloxane in biogas using the adsorption function of activated carbon, and is deposited as microcrystalline quartz in an igniter, valve, combustor, etc. to cause wear inside the motor. It is removed to less than 0.03 mg/m ^{3 .}

The primary gas filter 650 is installed at the rear end of the siloxane removal facility 640 to thirdly remove water in biogas, and 3rdly removes 99.7% or more of water in the biogas at the rear end of the siloxane removal facility. will do

The gas storage tank 660 is a storage means for temporarily storing biogas from which moisture, hydrogen sulfide, and siloxane have been removed, and the gas storage tank stores at least 1/4 of the biogas generated per day, and if the type is above ground, double membrane, underground In this case, the high-pressure tank method is used.

The secondary gas filter 670 is a filter means for removing moisture in the fourth order before using the biogas temporarily stored in the gas storage tank 660, and removes 99.8% or more of moisture from the biogas temporarily stored in the gas storage tank in the fourth order. do.

Accordingly, the biogas purification unit 600 is a four-stage device for water removal, including a water trap in the first stage, a chiller in the second stage, a primary gas filter in the third stage, a secondary gas filter in the fourth stage, and the biogas. As a two-stage desulfurization facility for removing hydrogen sulfide, the iron salt (FeCl ₃ ) injection facility in the first stage is located in the single-phase digester, and the dry desulfurization system of the second stage is included as an adsorption method, and the adsorption function of activated carbon is used Thus, it is preferable to include a siloxane removal facility for removing siloxane in biogas.

The biogas purification unit 600 is a biogas purification unit 600 due to corrosion of the biogas utilization facility by the moisture (2 to 12 vol.%) contained in the biogas and _{the HCl generated by the H 2} S reaction, and the operation cost increases, etc. It is a facility to solve the problem of , and consists of a water removal device, a hydrogen sulfide removal device and a siloxane removal device.

The detailed facilities of the biogas purification unit 600 include a water trap 610 that primarily removes moisture in biogas by a swirling flow method, and a secondarily removes more than 99.5% of moisture through cooling the firstly removed moisture. _{It consists of a chiller 620 and an iron salt (FeCl 3} ) injection facility and a second dry desulfurization facility 630 in the first single-phase digester for removing hydrogen sulfide contained in biogas.

At the rear end, a siloxane removal facility 640 that removes siloxane in biogas by using the adsorption function of activated carbon, and a siloxane removal facility 640 installed at the rear end of the siloxane removal facility 640 are the first to thirdly remove more than 99.7% of moisture in the biogas. The gas filter 650, the gas storage tank 660 for temporarily storing the biogas from which moisture, hydrogen sulfide and siloxane have been removed, and the second to remove 99.8% or more of moisture in the fourth before using the biogas temporarily stored in the gas storage tank Consists of a gas filter (670).

As described above, the facility for water removal in biogas consists of a total of 4 stages, and by allowing water contained in biogas to be maintained at 0.2% or less (removing more than 99.8%), the biogas power generation facility (710 ), it is possible to prevent the occurrence of corrosion in the co-fired boiler 730, etc. in advance.

First, in the first step, moisture is separated and removed to 60% or less in the water trap 610 by the swirling flow method. The water trap has a cylindrical shape and a cone structure at the bottom. In a cyclone type, biogas containing moisture is introduced into the upper part of the water trap, and a swirling flow is formed inside the water trap by high-speed centrifugal force. Moisture is primarily removed due to the specific gravity difference of the gas, and the removed moisture moves to the lower part and is transferred to the wastewater treatment facility 510 by an automatic valve.

The inner material of the water trap uses a material of STS 304 or higher so that there is no effect of corrosion due to the generation of HCl by the combination _{of H 2 S and water in biogas.} In addition, the biogas from which the primary moisture has been removed is transferred to the chiller 620, which is a secondary moisture removal device, through the upper part of the water trap.

The chiller 620 separates the condensate by cooling the biogas to a dew point or less. The chiller 620 is a device that cools the tube by evaporating the liquid refrigerant in the cooling tube, and the cooled tube liquefies the water in the biogas through cooling, and is composed of a compressor, a condenser, and an evaporator. More than 99.5% of water content in biogas is removed.

Moisture secondarily removed through the chiller 620 is removed by 99.7% or more while passing through the primary gas filter 650 and 99.8% or more while passing through the secondary gas filter 670 . The primary gas filter and the secondary gas filter have a vertical cylindrical structure, and 12 or more circular cartridge filters are installed inside. It can be removed and an automatic drain valve is installed in the lower part to automatically discharge the condensed moisture, the filter replacement is flange type on the upper part of the body, and the joint packing has strong resistance to corrosion by acid gas

The facility for removing hydrogen sulfide in biogas is composed of an iron salt (FeCl ₃ ) injection facility in the first single-phase digester 310 and a second dry desulfurization facility 630, and the H ₂ S concentration in biogas generated in the single-phase digester is It is usually 2,000 to 3,000 _{ppm, and it is possible to use it as an alternative fuel for power generation or LNG when this H 2} S concentration is lowered to about 10 ppm, so a wet desulfurization facility is usually used, but in the present invention, a chemical in the digester (FeCl ₃ ) By installing an injection facility, it _{reacts with H 2} S in biogas by injection of _{FeCl 3} to reduce H2S concentration according to FeS precipitate formation.

The concentration of FeCl ₃ is injected into the digester at 250 kg/d to lower the concentration of _{H 2} S in the biogas to 1,000 ppm or less as shown in [Table 3], and 450 kg/d to lower it to 500 ppm or less.

The drug injection facility consists of a drug storage tank, a drug transfer pump, and a drug transfer valve. _{By injection of FeCl 3 in} the primary digester, _{the concentration of H 2} S in the biogas is desulfurized to 500 to 1,000 ppm, and secondly, after desulfurization to 10 ppm in the dry desulfurization facility 630, it is transferred to the siloxane removal facility 34.

In the dry desulfurization facility, an adsorbent in the form of pellets of iron (III) hydroxide (Fe(OH) ₃ ) is filled in a vertical cylindrical reactor, and iron (III) sulfide (III) (Fe ₂ S _{) is reacted with H 2 S in biogas. 3} ) to remove _{H 2 S.}

- 2Fe(OH) ₃ + 3H ₂ S → Fe ₂ S ₃ + 6H ₂ O

- 2FeOOH + 3H ₂ S → Fe ₂ S ₃ + 4H ₂ O

The concentration of _{H 2} S flowing into the dry desulfurization facility 630 _{is reduced to 500 to 1,000 ppm according to the injection of FeCl 3} into the primary digester, and can be removed to 10 ppm or less while passing through the dry desulfurization facility.

In addition, since iron hydroxide (III) (Fe(OH) ₃ ) maintains a pellet shape away from the existing powder form, _{the removal efficiency of H 2} S is excellent as well as siloxane, which is one of the causative substances of fine dust in biogas. It can be removed and has the advantage of not being affected by moisture.

With the siloxane removal facility 640, which is the last process of the biogas purification unit 600, the siloxane concentration in the biogas is 1 to 400 mg/m ^{3 ,} and the siloxane is not removed, and the biogas power generation facility 710 or the co-fired boiler 730. It is deposited as microcrystalline quartz on igniters, valves, combustors, etc. and causes wear inside the motor, so it is removed to 0.03mg/m ³ or less through a siloxane removal facility.

The siloxane removal facility 640 has a vertical cylindrical shape in which activated carbon is filled therein, and 99.5% or more of moisture is removed through a water trap 610 and a chiller 620 in order to prevent a decrease in the removal rate of the activated carbon due to moisture, and the relative humidity is adjusted to 50% or less and flows into the activated carbon filling layer.

The activated carbon particles of the filling layer are in the form of pellets of 4 mm or more, the filling density of activated carbon is 500-700 kg/m ³ , and the contact time is 2 seconds or more. The siloxane concentration in the biogas is removed to ^{0.03 mg/m 3 or less.}

The biogas from which moisture, hydrogen sulfide, and siloxane have been removed through the biogas purification unit 600 is introduced into the gas storage tank 660 . The gas storage tank stores at least 1/4 of the biogas generated per day, and the type is double-membrane when it is above ground and high-pressure tank when it is underground.

Biogas from which foreign substances such as moisture, hydrogen sulfide, and siloxane have been removed through the biogas refining unit has a methane content of 60% or more, which passes through the biogas utilization unit 700 to generate and sell electricity through power generation or replace LNG in a co-fired boiler It is used as a fuel and also used as an alternative fuel for LNG in the dry fuel conversion facility 430 or the composting facility 440 of the post-processing unit 400 .

The biogas utilization unit 700 is a biogas utilization means that utilizes the biogas purified by the biogas purification unit 600, and the purified biogas generates electricity through power generation and the generated waste heat is generated through a waste heat boiler. Produce steam and use it in the thermal hydrolysis unit or use it as an alternative heat source for LNG in the co-firing boiler, producing steam and supplying it to the pyrolyzing unit, and using it as a biogas power plant (710), waste heat boiler (720), co-fired boiler (730) consist of.

The biogas power generation facility 710 is a power generation facility that generates and sells electricity by powering biogas from which moisture, hydrogen sulfide, and siloxane have been removed in the biogas purification unit 600 as fuel, and the purified biogas is biogas power generation. The electricity is produced through the facility 710, the produced electricity is sold, and the waste heat generated in the power generation process is recovered in the waste heat boiler 720 to produce steam, and the reaction tank 220 of the pyrolysis unit 200, which is the source of steam. ), the livestock manure storage tank 111 of the pre-processing unit 100, and the food storage tank 121 are supplied. The type of the biogas power generation facility 710 is preferably a gas turbine or engine power generation.

The waste heat boiler 720 is a boiler means for producing steam using waste heat generated in the power generation process of the biogas power generation facility 710 and supplying it as a heat source to the pre-processing unit 100 and the thermal hydrolysis unit 200,

The co-fired boiler 730 is a biogas purification unit 600 from which moisture, hydrogen sulfide, and siloxane have been removed to produce steam as a fuel and supply it as a heat source to the pretreatment unit 100 and the thermal hydrolysis unit 200 . is a means

In particular, in case the biogas power generation facility 710 is not operated due to regular inspection or failure, etc., the steam production used in the plant uses the biogas produced in the co-fired boiler 730 to produce steam and supply the steam to the required place. In addition, it is preferable that the co-fired boiler is capable of using biogas and LNG in a mixture.

In addition, the biogas utilization unit 700 is a facility that uses purified biogas, and can be divided into two utilization methods. The first is a biogas power generation facility that produces and sells electricity, and waste heat generated in the power generation process. is recovered from the waste heat boiler to produce steam, then supplied to the reaction tank of the thermal hydrolysis unit and supplied to livestock manure and food storage tanks. Second, purified biogas is supplied to the co-fired boiler and used as an alternative fuel for LNG. It is preferable to further include a facility for supplying the steam to the reaction tank of the thermal hydrolysis unit after producing the steam and supplying it to the livestock manure and food storage tank.

Hereinafter, in order to confirm the increase in the solubilization rate (VDS/VS, SCOD/TCOD ratio) after thermal hydrolysis compared to before thermal hydrolysis of the thermal hydrolysis unit 200 of the present invention, the thermal hydrolysis demonstration plant installed in some local governments for one year A total of 26 on-site sampling and laboratory analysis results at a price of 2 weeks are shown in [Table 2] below.

As shown in Table 2, the VDS/VS and SCOD/TCOD ratios after thermal hydrolysis compared to before thermal hydrolysis were analyzed to increase by 292.9% and 181.8%, respectively, solubilization of insoluble substances by the thermal hydrolysis unit 200 proceeds Accordingly, it is stably decomposed in a short residence time in the anaerobic digestion unit 300, and there is an effect of increasing biogas production by 10% or more compared to other technologies.

[Table 2] Analysis result of solubilization rate after thermal hydrolysis at the demonstration facility of the local government

In addition, in order to verify the change in the concentration of hydrogen sulfide in the biogas according to the chemical injection of the iron salt (FeCl3) injection facility in the single-phase digestion tank 310 as the primary desulfurization device for the removal of hydrogen sulfide in the biogas purification unit 600, some municipal demonstration facilities The experiment was conducted by changing the amount of iron salt injected for 6 months.

Experimental results iron salt to the biogas in a hydrogen sulfide (H2S) concentration according to the variation amount of (FeCl ₃₎ is started to decrease iron salts (FeCl ₃₎ input 250kg / d of the hydrogen sulfide concentration in the biogas showed a more than 1,000ppm, 450kg In /d, the concentration of hydrogen sulfide in biogas was analyzed to be less than 500 ppm.

Looking at the detailed analysis results, the concentration of hydrogen sulfide in biogas was 1,238-1,453 ppm (average 1,389 ppm) when iron salt was added at 100 kg/d, and when iron salt was added at 150 kg/d, the concentration of hydrogen sulfide in biogas was 1,047-1,451 ppm (average 1,264). ppm) was analyzed.

When 250 kg/d of iron salt is input, the concentration of hydrogen sulfide in biogas is 955-1,404 ppm (average 1,068 ppm), when iron salt 300 kg/d is input, the hydrogen sulfide concentration in biogas is 746-997 ppm (average 893 ppm), and when iron salt is input 350 kg/d The hydrogen sulfide concentration in biogas is 580-826ppm (average 717ppm), when 400kg/d of iron salt is input, the hydrogen sulfide concentration in biogas is 512-586ppm (average 533ppm), and when 450kg/d iron salt is input, the hydrogensulfide concentration in biogas is 489~ 447 ppm (average 465 ppm) was analyzed.

[Table 3-1] Changes in H2S concentration in biogas according to _{FeCl 3 injection}

[Table 3-2] Changes in H2S concentration in biogas according to _{FeCl 3 injection}

The present invention relates to an integrated livestock excretion technology for efficient integrated anaerobic digestion of mixed substrates for food waste including livestock manure and sewage residue. Each substrate brought in from the outside is crushed and sorted in a pre-treatment system to sort foreign substances and The particle size is homogenized (all substrates have a particle size of 3 mm or less).

In particular, the present invention is homogeneously mixed with food waste in a solid (cake) state through dehydration to prevent ammonia toxicity during anaerobic digestion by reducing the total nitrogen (TN) concentration contained in livestock manure and sewage residue. During integrated digestion through thermal hydrolysis and solubilization, methanogenic bacteria can easily decompose and form optimal conditions for anaerobic digestion.

In the present invention, in the integrated digestion system, integrated digestion is carried out by injecting a mixed substrate under the condition of an organic material loading rate of 2.0 to 2.5 kgVS/m ³ ·d through a single-phase anaerobic digestion tank, and the biogas generated in the integrated digestion process is lower than that of existing technologies. It is possible to increase production by more than 10%, and the digestion filtrate generated during integrated digestion is separated into solid and liquid through dehydration, and the liquid is treated or discharged in a sewage treatment plant after wastewater treatment.

The solid phase of the present invention is used to produce and use by-product compost or dry matter through composting or dry fueling, and the biogas produced during integrated digestion removes moisture, hydrogen sulfide, siloxane, etc. It can be used as an alternative heat source for LNG in the decomposition unit, or electricity is produced and sold through power generation, and the generated waste heat is used in the pyrohydrolysis system to achieve zero fossil fuel consumption and energy independence of the integrated fire extinguishing facility. Livestock manure integrated digestion system will be provided.

As described above, according to the present invention, it is possible to reduce the total nitrogen concentration flowing into the digester by 75% or more through the dehydration of livestock manure and sewage residues in the substrate pretreatment process, so that the inflow of high-concentration nitrogen into the digester during the integrated digestion of livestock manure of the existing technology It provides the effect of stable anaerobic digestion by removing in advance the effect on anaerobic digestion methanogenic bacteria due to ammonia toxicity.

The present invention removes foreign substances through crushing and screening for each substrate, and it is possible to derive optimal conditions for anaerobic digestion through high-temperature and high-pressure thermal hydrolysis solubilization, so it provides the effect of increasing the amount of biogas generated by 10% or more compared to the existing technology.

The present invention provides the effect of minimizing the area of the business site because it is possible to configure a single-phase digestion tank compared to the two-phase anaerobic digestion technology of the existing technology.

The present invention provides the effect of ensuring the economic feasibility of the facility through zero fossil fuel and energy independence since the produced biogas can be used as an alternative fuel for power generation or LNG after refining.

According to the dual configuration of the waste heat boiler and the co-fired boiler, the facility can be operated even during boiler failure or periodic inspection, so that the entire system can be operated without interruption, thereby maximizing the throughput of the input substrate.

The present invention described above can be embodied in various other forms without departing from the technical spirit or main characteristics thereof. Accordingly, the above embodiments are merely examples in all respects and should not be construed as limiting.

100: pre-processing unit 200: thermal hydrolysis unit
300: anaerobic digestion unit 400: post-processing unit
500: wastewater treatment unit 600: biogas purification unit
700: biogas utilization unit

Claims (10)

delete delete a pre-processing unit 100 for collecting and storing mixed substrates including livestock manure, food waste, and sewage residues to pre-treat the mixed substrates, respectively;
a thermal hydrolysis unit 200 installed downstream of the pretreatment unit 100 to solubilize the pretreated mixed substrate by thermal hydrolysis;
anaerobic digestion unit 300 installed downstream of the thermal hydrolysis unit 200 to decompose the mixed substrate in a single-phase digestion tank to generate biogas from organic waste resources and digest by microorganisms;
a post-processing unit 400 for storing the digestion filtrate after decomposition of organic waste resources through the anaerobic digestion unit 300 is completed, and dehydrating the digestion filtrate into a dehydrated cake and a desorption filtrate by centrifugation;
a wastewater treatment unit 500 for treating the desorption filtrate separated in the post-treatment unit 400;
a biogas purification unit 600 for refining and removing impurities contained in the biogas generated in the anaerobic digestion unit 300; and
Includes; biogas utilization unit 700 that utilizes the biogas purified by the biogas purification unit 600;
The pre-processing unit 100,
Livestock manure pre-treatment means for pre-treating livestock manure;
food pretreatment means for pretreating food waste;
sewage residue pre-treatment means for pre-treating sewage residue; and
Including; and an intermediate storage tank for storing the pre-treated livestock manure, food waste, and sewage waste;
The livestock manure pretreatment means,
Livestock manure storage tank for storing while heating livestock manure by steam;
It is installed downstream of the livestock excreta storage tank, a contaminant comprehensive treatment for removing foreign substances from the stored livestock manure;
a centrifugal dehydrator installed downstream of the contaminant comprehensive treatment machine to separate the livestock manure from which the foreign matter has been removed into solid and liquid and discharge the solid phase to the intermediate storage tank; and
and a wastewater treatment facility installed downstream of the centrifugal dehydrator to treat the separated liquid phase. a pre-processing unit 100 for collecting and storing mixed substrates including livestock manure, food waste, and sewage residues to pre-treat the mixed substrates, respectively;
a thermal hydrolysis unit 200 installed downstream of the pretreatment unit 100 to solubilize the pretreated mixed substrate by thermal hydrolysis;
anaerobic digestion unit 300 installed downstream of the thermal hydrolysis unit 200 to decompose the mixed substrate in a single-phase digestion tank to generate biogas from organic waste resources and digest by microorganisms;
a post-processing unit 400 for storing the digestion filtrate after decomposition of organic waste resources through the anaerobic digestion unit 300 is completed, and dehydrating the digestion filtrate into a dehydrated cake and a desorption filtrate by centrifugation;
a wastewater treatment unit 500 for treating the desorption filtrate separated in the post-treatment unit 400;
a biogas purification unit 600 for refining and removing impurities contained in the biogas generated in the anaerobic digestion unit 300; and
Includes; biogas utilization unit 700 that utilizes the biogas purified by the biogas purification unit 600;
The pre-processing unit 100,
Livestock manure pre-treatment means for pre-treating livestock manure;
food pretreatment means for pretreating food waste;
sewage residue pre-treatment means for pre-treating sewage residue; and
Including; and an intermediate storage tank for storing the pre-treated livestock manure, food waste, and sewage waste;
The food pretreatment means,
a food storage tank for storing food waste while heating it by steam;
a crushing separator installed downstream of the food storage tank to crush the stored food waste to sort foreign substances;
a pulper that is installed downstream of the crusher and finely crushes food waste and sorts foreign substances;
a drum screen installed downstream of the pulper to sort out foreign substances to uniform particles of food waste; and
and a cyclone installed downstream of the drum screen to separate and remove fine foreign substances in the food waste downward. 5. The method according to claim 3 or 4,
The sewage waste pretreatment means,
a sewage residue storage tank for storing sewage residues;
a drum screen installed downstream of the sewage residue storage tank to select foreign substances from the stored sewage residue;
a centrifugal dehydrator installed downstream of the drum screen to separate solid-liquid sewage residues from which the foreign substances are removed and discharge the solid phase to the intermediate storage tank; and
and a wastewater treatment facility installed downstream of the centrifugal dehydrator to treat the separated liquid phase. 5. The method according to claim 3 or 4,
The thermal hydrolysis unit 200,
a manufacturing tank for preheating the organic waste resources pretreated in the pretreatment unit 100 by recovering waste heat generated after the reaction of high temperature and high pressure steam;
a reaction tank receiving high-temperature and high-pressure steam to first destroy and solubilize cell walls of organic waste resources homogenized in the production tank;
a storage tank for solubilizing the cell wall of the organic waste resource in which the cell wall is primarily destroyed by pressure transporting the organic waste resource whose cell wall is primarily destroyed in the reaction tank and secondarily destroying the cell wall of the organic waste resource in which the cell wall is primarily destroyed according to pressure expansion through pressure drop;
a primary cooler for supplying cooling water from sewage treatment plant effluent to organic waste resources whose cell walls are secondarily destroyed in the storage tank for primary cooling to a temperature of 80°C to 85°C; and
An integrated digestion treatment apparatus for livestock manure, comprising a; a secondary cooler for supplying cooling water to a double-tube heat exchanger to secondarily cool the organic waste material cooled primarily to a temperature of 35°C to 40°C. 5. The method according to claim 3 or 4,
The anaerobic digestion unit 300 includes a scum remover for removing foreign substances from the upper part, a cyclone for removing foreign substances from the lower part, a digester overflow induction facility, and a vertical input for complete mixing and agitation in the digester. An integrated digestion treatment apparatus for livestock manure, characterized in that it consists of a axial mechanical agitator and a single-phase digester including a baffle. 5. The method according to claim 3 or 4,
The post-processing unit 400,
a digestion filtrate storage tank for temporarily storing the digestion filtrate generated in the anaerobic digestion unit 300;
a centrifugal dehydrator installed downstream of the digestion filtrate storage tank to separate the stored digestion filtrate into solid and liquid;
a dry fuel facility for producing dried products using the solid dewatering cake separated in the centrifugal dehydrator and using it as auxiliary fuel for a coal-fired power plant; and
Integrated digestion treatment apparatus for livestock manure, comprising: a composting facility for producing compost and supplying it to farms using the dehydrated cake, which is a solid phase separated from the centrifugal dehydrator. a pre-processing unit 100 for collecting and storing mixed substrates including livestock manure, food waste, and sewage residues to pre-treat the mixed substrates, respectively;
a thermal hydrolysis unit 200 installed downstream of the pretreatment unit 100 to solubilize the pretreated mixed substrate by thermal hydrolysis;
anaerobic digestion unit 300 installed downstream of the thermal hydrolysis unit 200 to decompose the mixed substrate in a single-phase digestion tank to generate biogas from organic waste resources and digest by microorganisms;
a post-processing unit 400 for storing the digestion filtrate after decomposition of organic waste resources through the anaerobic digestion unit 300 is completed, and dehydrating the digestion filtrate into a dehydrated cake and a desorption filtrate by centrifugation;
a wastewater treatment unit 500 for treating the desorption filtrate separated in the post-treatment unit 400;
a biogas purification unit 600 for refining and removing impurities contained in the biogas generated in the anaerobic digestion unit 300; and
Includes; biogas utilization unit 700 that utilizes the biogas purified by the biogas purification unit 600;
The biogas purification unit 600,
a water trap that primarily removes moisture in biogas by a swirling flow method;
a chiller installed downstream of the water trap to secondarily remove moisture through cooling;
a dry desulfurization facility installed downstream of the chiller to remove hydrogen sulfide contained in biogas;
a siloxane removal facility that removes siloxane in biogas using the adsorption function of activated carbon;
a primary gas filter installed at the rear end of the siloxane removal facility to thirdly remove moisture in biogas;
a gas storage tank for temporarily storing biogas from which moisture, hydrogen sulfide and siloxane have been removed; and
Integrated digestion treatment apparatus for livestock manure, comprising a; a secondary gas filter to remove moisture in the fourth before utilizing the biogas temporarily stored in the gas storage tank. a pre-processing unit 100 for collecting and storing mixed substrates including livestock manure, food waste, and sewage residues to pre-treat the mixed substrates, respectively;
a thermal hydrolysis unit 200 installed downstream of the pretreatment unit 100 to solubilize the pretreated mixed substrate by thermal hydrolysis;
anaerobic digestion unit 300 installed downstream of the thermal hydrolysis unit 200 to decompose the mixed substrate in a single-phase digestion tank to generate biogas from organic waste resources and digest by microorganisms;
a post-processing unit 400 for storing the digestion filtrate after decomposition of organic waste resources through the anaerobic digestion unit 300 is completed, and dehydrating the digestion filtrate into a dehydrated cake and a desorption filtrate by centrifugation;
a wastewater treatment unit 500 for treating the desorption filtrate separated in the post-treatment unit 400;
a biogas purification unit 600 for refining and removing impurities contained in the biogas generated in the anaerobic digestion unit 300; and
Includes; biogas utilization unit 700 that utilizes the biogas purified by the biogas purification unit 600;
The biogas utilization unit 700,
a biogas power generation facility that generates and sells electricity by powering biogas from which moisture, hydrogen sulfide, and siloxane are removed in the biogas purification unit 600 as fuel;
a waste heat boiler for producing steam using waste heat generated in the power generation process of the biogas power plant and supplying it as a heat source to the pre-processing unit 100 and the thermal hydrolysis unit 200; and
In the biogas purification unit 600, water, hydrogen sulfide, and siloxane are removed from biogas as fuel to produce steam and supply it as a heat source to the pre-processing unit 100 and the thermal hydrolysis unit 200. Containing; An integrated digestion treatment device for livestock manure, characterized in that.

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