KR102587714B1 - Slurry liquid fertilizer production and circulation compact system of livestock excrement with effect reducing odor, and Method for treating excrement of livestock using the same - Google Patents

Abstract

The present invention relates to a system for producing liquid manure from livestock manure, purifying and recycling part of the produced liquid manure, and a method for processing livestock waste using the same. A compact system for producing and circulating livestock waste that reduces odor from livestock manure, which can solve problems such as generation of odor, excessive use of energy due to aeration tank operation, excessive non-woven securing, and production of low-quality fertilizer due to low nitric oxide concentration in liquid manure, and treatment of livestock waste using this system. It's about method.

Description

Slurry liquid fertilizer production and circulation compact system of livestock excrement with effect reducing odor, and Method for treating excrement of livestock using the same}

The present invention relates to a livestock waste treatment method that solves the odor problem, which is a chronic problem in existing livestock manure treatment systems, especially pig barn manure treatment systems, while minimizing system site space and reducing energy use, and to a compact system for producing and circulating odor-reducing liquid manure used therein. .

In general, livestock manure from livestock farms usually has a biological oxygen demand (BOD) of tens of thousands of ppm, so it is not only difficult to treat to meet environmental standards, but also expensive to process. In particular, nitrogen, which causes significant environmental pollution, The high concentration of phosphorus has become a social problem when it is discharged into living environments such as rivers.

Recently, with the aim of maximizing resource use in the most environmentally friendly way, measures have been taken to convert livestock manure into resources in the form of compost or liquid fertilizer and provide it back to farming farms. This natural circulation agricultural and livestock farming method, in which livestock farms and crop farms are linked, converts livestock manure generated during the process of raising livestock into compost or liquid fertilizer and returns it to the crop farm, and the crop farm uses the livestock waste compost or liquid fertilizer to produce agricultural products. It is a method of cultivating and providing feed resources necessary for livestock farms.

As part of a plan to encourage natural circulation agricultural and livestock farming methods that link livestock farms and cultivating farms, Republic of Korea Patent Registration No. 10-1366374 (announced on February 24, 2014) requires the purification and composting process department and the bio gas production process department. It is an organic waste recycling treatment system that divides and processes livestock waste organic waste in the purification and composting process unit and the biogas production process unit, wherein the purification treatment and composting process unit separates the livestock waste organic waste into solid and liquid, and the remaining It sequentially includes a denitrification tank and a nitrification tank for treating wastewater, and the biogas production process unit includes an acid fermentation tank and a methane fermentation tank for separating biogas and digestion fluid from livestock manure organic waste, and receiving and processing the digestion fluid from the methane fermentation tank. A system for recycling organic waste into resources is disclosed, which includes a liquefaction facility, wherein the liquefaction facility performs liquefaction using digestion sap from the methane fermentation tank and liquid NO ₃ -N received from the nitrification tank.

In addition, a common method of removing bad odors and harmful gases from inside a pig pen is to use a ventilation system to force the air inside the pig pen to circulate or spray a substance that removes odor on the top of the pig pen to remove bad odors. This is a reality that not only costs a lot of money but also causes other problems due to the odor removal substances used. Accordingly, in connection with the aerobic liquid fertilizer produced by individual farms, it is continuously supplied to the lower part of the pit through a liquid fertilizer supply pipe in the form of an irrigation pipe for water supply, creating a flow of washing water without being affected by environmental factors, thereby reducing odor. An odor-reducing pig house cleaning circulation system using liquid fertilizer has been developed and provided to pig house farmers, which protects livestock and managers from various diseases and creates an eco-friendly livestock farming environment. However, to what extent is the odor problem within the pig house itself solved? , ammonia generated during the aerobic treatment of manure and the formation of aerobic liquid manure spreads foul odors to the outside of the pig pen, resulting in civil complaints, and low nitrogen oxides in the liquid manure due to excessive use of land and energy in the aerobic treatment system and low oxygen transfer efficiency. The decline in value as a fertilizer due to concentration is becoming a problem.

Republic of Korea Patent Publication No. 10-2012-0067514 (publication date 2012.06.26.) Republic of Korea Patent No. 10-1532371 (announcement date 2015.07.01.)

The technical problem to be solved by the present invention is the problem of the existing liquid manure production system for livestock manure, which is the generation of odor due to atmospheric volatilization of a large amount of ammonia nitrogen, excessive use of energy required in the aeration tank, large site requirement, and insufficient oxygen delivery. It is an invention that solves the decline in fertilizer value due to nitroxide concentration, and is a compact system for reducing odor caused by odor-causing substances such as ammonia nitrogen, aldehydes, sulfur compounds, and volatile fatty acids generated in livestock slurry pits, and producing and circulating liquid fertilizer linked to anaerobic digestion. The aim is to provide a livestock waste disposal method using this.

The present invention for achieving the above technical problem relates to a compact system for producing and circulating liquid manure to reduce odor of livestock manure, which is a pit consisting of a plurality of unit-type pits for producing a manure mixture by mixing manure from a livestock farm and circulated liquid manure. wealth; A contaminant removal unit that removes contaminants from the manure mixture in the pit area; A solid-liquid separation unit that separates and processes the manure mixture from which contaminants have been removed; An anaerobic digestion unit that produces anaerobic digestion by anaerobically digesting the liquid separated from the solid-liquid separation unit; and an aerobic digestion unit for aerobically treating the anaerobic digestion to produce liquid manure, and a nitrogen treatment unit for removing and recovering nitrogen from the anaerobic digestion liquid containing the anaerobic digestion is provided between the anaerobic digestion unit and the aerobic digestion unit. , a part of the liquid fertilizer produced in the aerobic digestion unit is circulated as liquid fertilizer in the pit unit and reused as washing water.

In addition, the present invention relates to a method for producing the odor-reducing liquid fertilizer and processing livestock waste using the circulating compact system.

The compact system for producing and circulating liquid manure to reduce odor from livestock manure of the present invention does not emit external ammonia generated during livestock manure treatment, so it is possible to produce high-quality liquid manure without odor problems, and biogas generated during livestock manure treatment. It has the effect of contributing to reducing greenhouse gases by recovering and recycling. In addition, because the system of the present invention can be built in a compact size, there is no excessive use of treatment facility land, which is a problem with existing livestock waste treatment systems, and by introducing the MABR process, which does not require oxygen supply through acid organs during aerobic treatment, It is possible to provide an energy-saving livestock waste treatment system that solves the problem of excessive energy use that occurs during existing aerobic treatment.

Figure 1 is a schematic process diagram of the entire process of the production and circulation system for odor-reducing liquid fertilizer for livestock waste of the present invention and the livestock waste treatment method using the same.
Figure 2a is a schematic process diagram of the process of the compost production unit of the present invention, and Figure 2B is a schematic process diagram of a preferred embodiment of the compost production unit process.
Figure 3 is a schematic process diagram for the nitrogen treatment unit process.

Hereinafter, the liquid fertilizer production and circulation system for reducing odor of livestock waste of the present invention and the livestock waste treatment method using the same will be described in detail.

The liquid manure production and circulation system for reducing odor of livestock manure of the present invention is non-discharge-free, odor-free, and compact in configuration without external discharge of waste from livestock waste and system operation, saving space and being easy to operate. and a liquid fertilizer circulation system capable of operating stability and energy saving, as shown in a schematic process diagram in FIG. 1, a pit portion; impurity removal unit; solid-liquid separation unit; Anaerobic digestion; and an aerobic digestion unit; and a nitrogen treatment unit for removing and recovering nitrogen from the anaerobic digestion liquid containing the anaerobic digestion is provided between the anaerobic digestion unit and the aerobic digestion unit.

First, when describing the pit part, the pit part is composed of a plurality of unit-type pits for producing a manure mixture by mixing manure from a livestock farm and circulated liquid manure.

The plurality of unit-type pits are formed in several rows using concrete to have a certain width and depth, and the upper part of the pit is installed at regular intervals with several pipes for discharging slurry and washing water that are opened and closed by slurry balls on the bottom. Several wire mesh-type floor plates may be installed in succession to be detachable, allowing manure excreted by pigs to fall to the bottom of the pit.

In addition, the pit portion includes a liquid fertilizer storage tank that stores liquid fertilizer that is recycled by circulating a portion of the liquid fertilizer generated in the aerobic digestion unit; a liquid fertilizer supply pump that supplies the liquid fertilizer stored in the liquid fertilizer storage tank through a liquid fertilizer supply pipe installed through a liquid fertilizer supply pipe installed at a predetermined height on one wall of the pit; A liquid fertilizer supply amount control valve installed on the liquid fertilizer supply pipe to control the supply amount of liquid fertilizer delivered into the pit from the liquid fertilizer delivery pump; It is installed in the washing water discharge pipe installed between the other wall of the pit and the sump to clean the inside of each unit-type pit and control the discharge amount of liquid fertilizer discharged to the sump to maintain the water level in each unit-type pit at a constant level. A liquid fertilizer discharge control valve to maintain; and/or a water collection tank for collecting the washing water and pig manure slurry discharged through the washing water discharge pipe and the slurry and washing water discharge pipes.

In addition, each of the plurality of unit-type pits is formed by installing a partition at a predetermined interval within the pit, and in each partition, a liquid fertilizer passage hole for pit cleaning is drilled at an opposite position, so that the liquid fertilizer is divided into each unit unit-type pit. It may be installed and formed to be cleaned by passing in a zigzag manner diagonally opposite to each other.

Additionally, the bottom of the unit-type pit may be formed to taper from the edge to become deeper toward the center where the pipe for discharging slurry and washing water is installed.

In addition, one end of the opening and closing string is fixed to the slurry ball, and the other end of the opening and closing string is tied to the wire mesh bottom plate of the pit, and then the slurry is released from the outside using the opening and closing string without removing the wire mesh bottom plate. It is also possible to separate the slurry balls blocking the opening of the pipe for discharging the washing water and clean the bottom of the unit type pits.

In addition, the liquid fertilizer delivery pump can be controlled by the control unit to be driven only for a set period of time, and the liquid fertilizer supply control valve and the liquid fertilizer discharge control valve are electronic valves or solenoid valves whose opening and closing amounts are automatically controlled by the control unit. Can be installed. In addition, the liquid fertilizer supply control valve and the liquid fertilizer discharge control valve may be provided with a timer and a timer valve that opens and closes at a predetermined time for a predetermined time together with the liquid fertilizer delivery pump may be installed.

Next, in the system of the present invention, the contaminants removal unit can remove contaminants in the manure mixture through a screen, cyclone, etc. to perform a process of removing contaminants from the manure mixture in the pit.

Next, in the system of the present invention, in the solid-liquid separation unit, a process of solid-liquid separation is performed on the excrement mixture from which contaminants have been removed in the contaminant removal unit, preferably through sedimentation, pressure flotation, or centrifugation. Solid and liquid can be separated by pressure flotation.

The separated solid phase is delivered to the compost manufacturing section and processed into compost to produce compost. Part of the solid-liquid separated liquid phase can be recycled as washing water in the pit section, and the remaining liquid phase is transferred to the anaerobic digestion section.

As shown in the schematic process diagram in FIG. 2A, the compost manufacturing unit is equipped with a bio-fermentation dryer, a molding machine, an unused latent heat recovery dryer, and a membrane dryer, and the solid phase separated from the solid-liquid separation unit is separated into the biological Step 1: aerobic biodegradation and primary drying in a fermentation dryer; Step 2: molding the first dried product in the molding machine; and a third step of producing compost (and/or solid fuel) by secondary drying the molded primary dried product in an unused latent heat recovery dryer.

The exhaust gas generated from the biological fermentation dryer in the first step is supplied to the membrane dryer to remove moisture in the exhaust gas and recover the moisture. The gas from which the moisture has been removed is re-supplied to the biological fermentation dryer for recycling, and the recovered moisture is recycled. Latent heat is recovered within a few minutes by supplying it from a heat exchanger, and the recovered latent heat is reused in the unused latent heat recovery dryer for secondary drying. In other words, the recovered latent heat can be reused as a heat source for secondary drying.

The biofermentation dryer supplies excess air than the minimum air requirement for decomposition of biodegradable organic materials, and dries moisture in the waste using reaction heat (heat of respiration) generated when decomposition of biodegradable organic materials by aerobic microorganisms. , It is a very economical drying method as it can efficiently induce moisture evaporation without inputting additional external energy. In addition, wet gas is generated when organic materials are decomposed by aerobic microorganisms, which is transferred to a membrane dryer.

The membrane dryer is a dryer equipped with a gas separation membrane, which removes air pollution and odor-causing substances and separates water vapor from the wet gas transferred from the biofermentation dryer, and transfers the separated water vapor to a heat exchanger to recover and recycle the latent heat in the water vapor. make it possible In addition, condensation heat is recovered in the heat exchanger, the recovered heat is input into a secondary dryer for unused latent heat recovery, and the condensate can be discharged and recycled outside the heat exchanger.

Compost and/or solid fuel can be produced by molding the dried material primarily in a biofermentation dryer into a certain shape in a molding machine, and then secondarily drying the molded material in an unused latent heat recovery dryer. As described above, the unused latent heat recovery dryer can use the latent heat recovered from the heat exchanger as a heat source, and can also receive heat from a separate heat source in addition to the latent heat.

The solid phase supplied to the biofermentation dryer may have a moisture content of 65 to 70% by weight, and the compost (and/or solid fuel) produced by performing step 3 may have a moisture content of 20% by weight or more.

In addition, the membrane dryer can have a moisture removal rate of more than 90% for the supplied wet gas, a dry air circulation rate of 75 to 80%, a heat recovery amount from dry air circulation of 6,000 to 7,000 kcal/hr, and latent heat recovery. The quantity may be 50,000 to 65,000 kcal/hr. Additionally, the latent heat exchange input amount from the heat exchanger to the secondary dryer for recovering unused latent heat may be 5,500 to 7,000 kcal/hr.

In this regard, a preferred example of the conditions for the production process of solid compost (and/or solid fuel) in the compost production unit is shown in FIG. 2b.

Next, in the system of the present invention, the anaerobic digestion unit performs a process of producing anaerobic digestion by anaerobically digesting the liquid phase separated from the solid-liquid separation unit.

In the present invention, the anaerobic digestion unit uses an upflow anaerobic sludge blanket (UASB) method that applies high-efficiency anaerobic digestion technology based on granule sludge. Anaerobic granular sludge is a form in which microorganisms are aggregated to the size of a fingernail and are very hard to the touch. As a result, a high density of microorganisms is secured per grain, making it an organic material with high performance even in a small area and short residence time. This is a method that allows removal. In addition, unlike general anaerobic digestion, there is no separate gas holder, and the headspace inside the anaerobic reaction tank is manufactured as an integrated type where biogas storage and discharge occur, so it can play a significant role in the compact structure of the process. In addition, because the anaerobic reaction tank has a vertical cylindrical shape, the granular sludge contains biogas generated during the decomposition of organic matter and repeatedly rises and falls in the water, colliding with surrounding suspended growth microorganisms and having a very high density. .

The anaerobic digestion unit of the present invention can shorten the treatment time by about 2 times or more compared to the existing anaerobic digestion process, and can be applied up to an applicable inlet load of about 7 kg/m ³ /d or more, so the residence time is 3 to 10 days. You can drive within

In the present invention, the anaerobic digestion unit is a two-phase anaerobic digestion unit equipped with a production tank and a methane production tank.

The acid production tank is a plug-flow reactor (PFR), and performs a solubilization process on the liquid phase separated from the solid-liquid separation unit to produce a dissolved solubilized liquid, and the produced dissolved solubilized liquid is transferred to a methane production tank. Deliver.

In addition, the methane production tank is performed by the upflow anaerobic sludge method (UASB), and the dissolved solubilized liquid is subjected to anaerobic digestion treatment.

In addition, it is preferable that the liquid phase flowing into the anaerobic digestion unit has a solid concentration of 1,000 mg/L or less.

In addition, through the cleaning process of returning the effluent from the methane production tank to the acid production tank, it is possible to maximize the dissolved substances sent to the methane production tank and prevent pH decrease (replenishing alkalinity) due to an increase in organic acids in the acid production tank, and the residence time of the process. Effects such as reduction of overall retention time in the process can be achieved through separation of SRT (Solids Retention Time) of methane-producing microorganisms.

Additionally, by collecting biogas containing methane generated in a methane production tank, using it as a heat source for a hot water boiler, and reusing the hot water from the boiler to heat the methane production tank, greenhouse gases can be reduced and energy recycled.

In this way, by introducing the upflow anaerobic sludge method for the anaerobic digestion unit, the retention time of the anaerobic digestion is minimized, the site area of the anaerobic digestion unit is minimized, and the solids in the anaerobic digestion are minimized to reduce the burden of the subsequent process and achieve an energy recycling effect. You can.

In addition, the anaerobic digested product anaerobically digested in the anaerobic digestion unit of the present invention has a TCODcr removal rate of 70-85%, a SCODcr removal rate of 70-85%, a total solids (TS) removal rate of 60-80%, and Ammonia nitrogen (NH ₄ -N) removal rate of 5 to 15% can be satisfied, preferably TCODcr removal rate of 75 to 85%, SCODcr removal rate of 75 to 85%, total solids (TS) removal rate of 65 to 80%, and ammonia nitrogen. (NH ₄ -N) removal rate of 7 to 15% can be satisfied.

Next, in the system of the present invention, the nitrogen treatment unit performs a process of separating, removing, and recovering excess ammonia nitrogen from the anaerobic digestion liquid containing the anaerobic digestion treated anaerobically in the anaerobic digestion tank, as schematically shown in FIG. 3. By doing so, it controls the nitrogen content in the anaerobic digest that flows into the aerobic digestion unit to control stable operation and prevents the occurrence of odor.

In the present invention, the nitrogen treatment unit introduces a membrane contactor method using an ammoniacal nitrogen recovery method based on membrane filtration. For a specific example, as can be seen through the schematic process diagram of FIG. 3, after transferring the anaerobic digestion (digestion liquid) containing high concentration of ammonia nitrogen generated in the anaerobic digestion unit to the membrane contactor, the anaerobic digestion (digestion liquid) is transferred to the membrane contactor. NH ₃ is separated from the digestion liquid, and the separated NH ₃ can be obtained by reacting with sulfuric acid and being converted to ammonium sulfate. Then, the effluent containing low concentration of NH ₃ from which NH ₃ has been separated and removed is supplied again to the anaerobic digestion unit. .

In addition, the anaerobic digestate (digestion liquid), which is the inflow water supplied from the anaerobic digestion unit, can be supplied after adjusting the pH with NaOH before being supplied to the membrane contactor, and the appropriate pH is selected according to the AFC (Ammonia fraction curve), which is It represents the rate at which NH ₄ ⁺ ions in water are converted to NH ₃ (free ammonia) depending on temperature and pH. When the anaerobic digester operates at about 28 to 32°C, the appropriate pH is about 10 to 11. If the pH is less than 10, the ratio of NH ₃ is lowered, so there may be a problem of reduced nitrogen recovery efficiency. Since the pH is already converted to NH ₃ at about 11, if it exceeds this, there may be a problem of increased costs due to excessive consumption of chemicals. Therefore, it is recommended to adjust the pH to the above range and then add the anaerobic digestate (digestion liquid) to the membrane contactor.

In the present invention, the nitrogen treatment unit does not cause odor problems because it is operated in a closed system, the facility is compact and requires a small amount of site space, and the concentration gradient between the extinguishing liquid flowing inside the membrane contactor and the sulfuric acid solution outside is maintained. Since degassing and absorption are performed through diffusion, it can operate as a low-energy, low-noise process.

In addition, the treated water filtered by a membrane contactor in the nitrogen treatment unit of the present invention has a total nitrogen (TN) removal rate of 40 to 60% and ammonia nitrogen (NH ₄ -N) relative to the supplied anaerobic digested anaerobic digest (digestion liquid). A removal rate of 40 to 60% can be satisfied, preferably a total nitrogen (TN) removal rate of 45 to 60% and an ammonia nitrogen (NH ₄ -N) removal rate of 45 to 60%.

Next, in the system of the present invention, the aerobic digestion unit performs a process of producing liquid manure by aerobically treating the anaerobic digestion, and a portion of the liquid manure produced in the aerobic digestion unit is circulated to the liquid manure of the pit unit and reused as washing water. and the remainder is produced as liquid fertilizer.

Anaerobic digestion liquid has a high ammonia concentration and has the characteristic that the ammonia concentration can vary greatly depending on the condition of the raw water and the operating conditions of the digester. Generally, it is an aerobic digestion solution that produces liquid manure from livestock waste through aeration using an air diffuser. In the case of the digestion process, if a high concentration of ammonia is introduced, oxygen consumption can significantly increase. Due to low oxygen transfer efficiency and low nitrification due to insufficient oxygen supply, the remaining ammonia has a toxic effect on microorganisms (FA inhibition), causing aerobic It may cause digestion inhibition, and if there is a large change in the ammonia inflow load in the influent, it may cause a decrease in process stability.

Therefore, in the present invention, the aerobic digestion unit is performed by introducing a membrane aerated biofilm reactor (MABR, Membrane Aerated Biofilm Reactor) rather than aerobic digestion using an aeration tank, and the gas separation membrane of the MABR may be composed of a hollow fiber-type gas separation membrane.

The MABR treats anaerobic digestion aerobically by using a non-bubble oxygen supply method using an oxygen diffusion method using a gas separation membrane. It does not require oxygen supply due to the generation of bubbles through a diffuser, etc., and there is no volatilization of odorous components due to the generation of bubbles. The occurrence of odor can be minimized or prevented. In addition, among the microorganisms attached to the gas separation membrane and forming a biofilm, oxygen can be supplied preferentially to nitrifying microorganisms, resulting in high nitrification efficiency. Aerobic treatment in existing aeration tanks has an oxygen transfer rate of about 20%, and the oxygen transfer rate in wastewater is high. About 30% of ammonia is degassed, causing bad odor, and the aerobic treatment residence time is long, so a large site is required. However, the MABR has a very high oxygen transfer of about 70 to 90%, so the residence time is short, so only a low site is required. Not only is this required, there is no odor caused by ammonia degassing, and highly aerobic digestion treatment is possible with only low power supply.

In addition, the liquid fertilizer prepared by aerobic digestion in the aerobic digestion unit of the present invention has a TCODcr removal rate of 70-85%, a SCODcr removal rate of 70-85%, and a total solids (TS) removal rate of 80% for the anaerobic digestate (digestion liquid) supplied to the anaerobic digestion unit. ~95%. Ammonia nitrogen (NH ₄ -N) removal rate of 80 to 95% and total phosphorus (TP) removal rate of 10 to 30% can be satisfied, preferably TCODcr removal rate of 75 to 85%, SCODcr removal rate of 75 to 85%, and total solids ( TS) Removal rate 85-95%. Ammonia nitrogen (NH ₄ -N) removal rate of 85-95% and total phosphorus (TP) removal rate of 15-25% can be satisfied.

The odor-reducing liquid fertilizer production and circulation compact system of the present invention, which consists of the pit section, impurity removal section, solid-liquid separation section, anaerobic digestion section, nitrogen removal section, and aerobic digestion section described above, is capable of producing compost (compost) from various livestock manure, preferably pig manure. and/or solid fuel) and liquid manure, and some of the produced liquid manure can be purified into peat and used as washing water, making it an environmentally friendly and highly economical treatment method for livestock manure, preferably pig manure.

In addition, the livestock waste odor reduction liquid fertilizer production and circulation system of the present invention described above and the livestock waste treatment method using the same are very easy to maintain because the overall process can be automatically controlled through an ICT-based integrated operation system.

Hereinafter, the present invention will be described in more detail through the following examples and experimental examples. However, the following examples and experimental examples are intended to illustrate the present invention and the scope of the present invention is not limited by these examples and experimental examples.

[Example]

Example 1: Production of odor-reducing liquid fertilizer and treatment of pig manure using a circulating compact system

(1) As shown in the schematic process diagram in FIG. 1, a pit section consisting of a plurality of unit-type pits that mixes pig pen manure and circulated liquid manure to produce a manure mixture, and a pit section that removes impurities from the manure mixture in the pit part. A removal unit, a solid-liquid separation unit that separates and processes the manure mixture from which contaminants have been removed, and an anaerobic digestion unit that produces anaerobic digestion by anaerobically digesting the liquid separated from the solid-liquid separation unit. A pilot experiment was performed consisting of a nitrogen treatment unit that removes and recovers nitrogen from the anaerobic digestate containing the anaerobic digestate, and an aerobic digestion unit that aerobically treats the anaerobic digestate to produce liquid fertilizer.

At this time, part of the liquid fertilizer produced in the aerobic digestion unit was circulated as liquid fertilizer in the pit unit and reused as washing water, and waste generated during system operation was not discharged to the outside.

In addition, the anaerobic digestion unit is composed of a two-phase anaerobic digestion unit including an acid production tank equipped with a plug-flow reactor (PFR) and a methane production tank equipped with an upflow anaerobic sludge reactor, and the anaerobic digestion unit The solids concentration of the liquid flowing into the system was set to 1,000 mg/L or less. In addition, the biogas generated in the methane production tank was reused as fuel for the boiler, and the boiler was used as a heat source to heat the methane production tank of the anaerobic digestion unit.

In addition, the nitrogen treatment unit introduced membrane contactor technology, and the anaerobic digestion (digestion liquid) containing high concentration of ammonia nitrogen generated in the anaerobic digestion unit was adjusted to pH 10 to 11 with NaOH (anaerobic digestion tank). (when the temperature is about 30 ℃), it was transferred and injected into the membrane contactor, and the ammonium sulfate (absorbed liquid) formed when the separated NH ₃ reacted with sulfuric acid through the membrane was separately collected, and the treated water from the membrane contactor was sent to the anaerobic digestion unit. It was re-transferred and supplied to the methane production tank.

In addition, the aerobic digestion unit was equipped with a membrane aeration biofilm reactor (MABR) equipped with a hollow fiber gas separation membrane.

Pig manure, slurry pit (manure mixture) mixed with liquid manure circulated in the pit, liquid phase separated from solid and liquid, anaerobic digested product anaerobically digested in the anaerobic digestion unit, and nitrogen recovered and treated from the nitrogen recovery unit to the membrane contactor. The properties of the treated water and the liquid fertilizer produced in the aerobic digestion unit are shown in Tables 1 and 2 below.

And, flow rate (Q, m ³ /d), TCODcr (Total Chemical Oxygen Demand) concentration, SCODcr (Soluble hemical Oxygen Demand) concentration, TS (Total Solids) concentration, TN (Total Nitrogen) concentration, TKN (Total Measure kjeldahl nitrogen (total Kendall nitrogen) concentration, Org-N (organic nitrogen) concentration, NH ₄ -N (ammonia nitrogen) concentration, NO ₃ -N (nitrate nitrogen) concentration, and TP (Total Phosphorous) concentration. did.

division pig manure Characteristics of slurry pits Solid-liquid separation conditions and liquid properties density
(mg/L) load
(kg/d) density
(mg/L) load
(kg/d) density
(mg/L) load
(kg/d) Removal rate (%) Q( ^m3 /d) One 5 5 TCODcr 50,000 50 10,331 51.65 8,264 41 20 SCODcr 30,000 30 6,250 31.25 6,250 31 - TS 100,000 100 20,121 100.60 4,024 20 80 TN 5,000 5 1,141 5.71 791 4 - T.K.N. 5,000 5 1,014 5.07 664 3 - Org-N 3,500 4 700 3.50 360 2 50 NH ₄ -N 1,500 2 314 1.57 314 2 0 NO ₃ -N - - 127 0.64 127 One 0 TP 300 0 139 0.69 111 One 20

division Anaerobic digestion unit and anaerobic digestion properties Treated water from membrane contactor Aerobic digestion and produced liquid slurry properties density
(mg/L) load
(kg/d) removal rate
(%) density
(mg/L) load
(kg/d) removal rate
(%) density
(mg/L) load
(kg/d) removal rate
(%) Q( ^m3 /d) ⁽¹⁾ 5 5 5 TCODcr ⁽²⁾ 1,653 8 80 1,653 8 0 331 2 80 SCODcr ⁽³⁾ 1,250 6 80 1,250 6 0 250 One 80 TS ⁽⁴⁾ 1,207 6 70 1,207 6 0 121 One 90 TN ⁽⁵⁾ 410 2 - 269 One 50 141 One - TKN ⁽⁶⁾ 283 One - 141 One - 14 0 - Org-N ⁽⁷⁾ - - 100 - - 0 - - 0 NH ₄ -N ⁽⁸⁾ 283 One 10 141 One 50 14 0 90 NO ₃ -N ⁽⁹⁾ 127 One 0 127 One 0 127 One - TP ⁽¹⁰⁾ 111 One 0 111 One 0 89 0 20

(2) In addition, the solid-liquid separation unit performs solid-liquid separation using a pressure flotation method, and the solid phase (moisture content 67.5 to 68.0% by weight) separated from the solid-liquid separation unit is delivered to the compost production unit and processed into compost to produce compost, and the solid-liquid separation unit is processed into compost. Part of the separated liquid was recycled as washing water for the pit.

The compost production unit is equipped with a bio-fermentation dryer, a molder, an unused latent heat recovery dryer, a membrane dryer, and a heat exchanger (see Figure 2a), and the solid phase separated from solid and liquid, the primary dried product dried in the bio-fermentation dryer. , the solid content and moisture of the molded dried product and the compost, which is a secondary dried product dried in a secondary dryer, are shown in Table 3 below.

division solid-liquid separated
elegance primary dry matter
(Biological fermentation dryer) molded building secondary dry matter
(compost) Solid content (kg/hr) 72.92 54.69 54.69 54.69 Moisture (kg/hr) 135.42 29.09 23.13 13.67

In addition, the temperature, air input amount, moisture content, and humidity of the outside air input to the biological fermentation dryer, the wet gas supplied from the biofermentation dryer to the membrane dryer, the dry air supplied to the membrane dryer from the outside air, and the water vapor separated and recovered from the membrane dryer. is shown in Table 4 below.

division outside air dry air wet gas vapor Temperature (℃) 10 60 60 60 Air input amount (kg/hr) 140 562 702 140 Moisture content (kg/hr) 0.7 10.7 107.1 106.3 Absolute humidity (kg/kg) 0.008 0.019 0.152 0.152 Relative humidity (%) 70 16.6 100 100

Additionally, the amount of heat recovered from dry air was 6,749 kcal/hr, the amount of latent heat recovered from the water vapor separated from the membrane dryer was 57,312 kcal/hr, and the amount of latent heat exchange input into the secondary dryer was 6,219 kcal/hr.

Through the above examples, it is possible to efficiently produce and recycle liquid manure from livestock manure such as pig manure using the odor-reducing liquid manure production and circulation compact system of the present invention, and by efficiently producing compost, excellent livestock manure treatment is achieved. It was confirmed that a method could be provided.

Claims (11)

A pit section consisting of a plurality of unit-type pits for producing a manure mixture by mixing the manure from the livestock farm and the circulated liquid manure;
A contaminant removal unit that removes contaminants from the manure mixture in the pit area;
A solid-liquid separation unit that separates and processes the manure mixture from which impurities have been removed;
A two-phase anaerobic digestion unit that produces anaerobic digestion by subjecting the liquid separated from the solid-liquid separation unit with a solid concentration of 1,000 mg/L or less to anaerobic digestion using an upflow anaerobic sludge blanket; and
It includes an aerobic digestion unit that aerobically processes the anaerobic digest to produce liquid fertilizer,
It further includes a nitrogen treatment unit between the anaerobic digestion unit and the aerobic digestion unit to remove and recover nitrogen from the anaerobic digestion liquid containing the anaerobic digestion product,
The solid phase separated from the solid-liquid separation unit is delivered to the compost manufacturing unit and processed into compost to produce compost,
A portion of the solid-liquid separated liquid phase is recycled as washing water in the pit section, and a portion of the liquid fertilizer produced in the aerobic digestion section is circulated as a liquid fertilizer in the pit section and reused as washing water,
The two-phase anaerobic digestion unit includes an acid production tank and a methane production tank,
The acid production tank is a plug-flow reactor (PFR), and performs a solubilization process on the liquid phase separated from the solid-liquid separation unit to produce a dissolved solubilized liquid, and the produced dissolved solubilized liquid is transferred to a methane production tank. Delivered, the methane production tank is performed by the upflow anaerobic sludge method (UASB), and the dissolved solubilized liquid is anaerobically digested,
Returning the effluent from the methane production tank to the acid production tank,
The aerobic digestion unit is performed using a membrane aerated biofilm reactor (MABR) consisting of a hollow fiber gas separation membrane,
The biogas generated in the anaerobic digestion unit is reused as fuel for the boiler, and the boiler is a heat source that heats the digester of the anaerobic digestion unit,
The anaerobic digestate has a TCODcr removal rate of 70 to 85%, a SCODcr removal rate of 70 to 85%, a total solids (TS) removal rate of 60 to 80%, and an ammonia nitrogen (NH ₄ -N) removal rate of 5 for the liquid supplied to the anaerobic digestion unit. Satisfies ~ 15%,
The treated water filtered by a membrane contactor in the nitrogen treatment unit satisfies the total nitrogen (TN) removal rate of 40-60% and the ammonia nitrogen (NH ₄ -N) removal rate of 40-60% for the supplied anaerobic digestion. ,
The liquid fertilizer prepared through aerobic digestion has a TCODcr removal rate of 70-85%, a SCODcr removal rate of 70-85%, and a total solids (TS) removal rate of 80-95% for the anaerobic digestate supplied to the anaerobic digestion unit. The ammonia nitrogen (NH ₄ -N) removal rate is 80 to 95% and the total phosphorus (TP) removal rate is 10 to 30%.
A compact system for producing and circulating liquid manure to reduce odor from livestock manure, characterized by no external discharge of waste generated during livestock manure and system operation.
The compact system for producing and circulating liquid manure for reducing odor from livestock waste according to claim 1, wherein the solid-liquid separation unit separates the solid-liquid through a pressure flotation method.
The method of claim 2, wherein the compost production unit is equipped with a bio-fermentation dryer, a molding machine, an unused latent heat recovery dryer, and a membrane dryer,
A first step of aerobic biodegradation and primary drying of the solid phase separated in the solid-liquid separation unit in the biofermentation dryer; Step 2: molding the first dried product in the molding machine; And a third step of producing compost by secondary drying the formed primary dried material in an unused latent heat recovery dryer,
The exhaust gas generated from the biological fermentation dryer in the first stage is supplied to the membrane dryer to remove moisture in the exhaust gas and recover the moisture. The gas from which the moisture has been removed is re-supplied to the biological fermentation dryer for recycling, and the recovered moisture is used for heat exchange. A compact system for producing and circulating liquid manure to reduce odor from livestock manure, characterized in that the latent heat in water is recovered by supplying it from the dryer and reused in the unused latent heat recovery dryer for secondary drying.
According to claim 3, wherein the solid phase in the first stage has a moisture content of 65 to 70% by weight, and the compost in the third stage has a moisture content of 20% by weight or less.
According to claim 3, wherein the compost is used as solid fuel. A liquid fertilizer production and circulation compact system for reducing odor of livestock manure.
delete delete delete delete The compact system for producing and circulating liquid fertilizer for reducing odor of livestock waste according to any one of claims 1 to 5, wherein the livestock waste is pig waste.
A method for processing livestock manure using an odor-reducing liquid fertilizer production and circulation compact system according to any one of claims 1 to 5.