KR20080085125A - Processing unit for organic waste materials and method thereof - Google Patents

Abstract

An apparatus for treating organic waste liquids and a method for treating organic waste liquids are provided to increase efficiency of the high efficiency anaerobic process, increase generation efficiency of methane(CH4), actively utilize recovered nitrogen and phosphorous as resources such as fertilizers, minimize retention time, increase recovery ratio of organic matters, and solve toxicity problems of ammonia generated from an anaerobic digester. A wastewater treatment system(100) comprises: a first pre-treatment part(112) for removing solids contained in wastewater; a first settling part(114) connected to the first pre-treatment part to settle sediment contained in the pre-treated wastewater; a biological reactor(116) connected to the first settling part to degrade organic matters and remove the degraded organic matters by reacting wastewater flown into the biological reactor with microorganisms; a second settling part(124) connected to the biological reactor to separate treated water from sludge that has been formed by the biological reaction; a concentration part(126) for concentrating sludge generated by the second settling part; and an apparatus(131) for treating organic waste liquid including a high pressure homogenizer(132) for crushing at least one of sludge concentrated by the concentration part and the sediment settled by the first settling part to form a liquid phase, a solid-liquid separating acid fermentation tank(134) for subjecting treated water discharged from the high pressure homogenizer to acid fermentation and solid-liquid separation, and a high efficiency anaerobic tank(136) for digesting organic matters discharged from the solid-liquid separating acid fermentation tank to recover methane. The apparatus for treating organic waste liquids additionally includes a nutrient recovery tank(138) for recovering nitrogen and phosphorous contained in treated water discharged from the high efficiency anaerobic tank. The wastewater treatment system further comprises a second pre-treatment part(128) for removing solids contained in organic waste, and a retention tank(130) for storing the organic waste pre-treated by the second pre-treatment part.

Description

Processing unit for organic waste materials and method

The present invention relates to a wastewater treatment technology, and more particularly, to an apparatus and an organic wastewater treatment method capable of organic wastewater treatment.

Organic waste liquor contained in livestock manure, sewage sludge, or food waste is not only difficult to treat, but also costs 100 to 300 times the cost of sewage treatment. For this reason, most of organic waste is dumped to the ocean. Ocean dumping of organic waste fluids not only causes marine pollution, but also results in returning to humans through biological accumulation.

Ocean dumping of organic waste liquids has become a problem internationally, and countries have banned all dumping by 2011 through the London Convention.

Recently, in order to solve this problem, a method of treating organic waste liquid through anaerobic digestion has been in the spotlight. According to the anaerobic digestion, since organic matter is produced from methane gas, useful resources can be recovered.

 However, anaerobic digestion has a disadvantage that the residence time in the reactor for the treatment is long because the reaction rate is very slow. This problem may vary depending on the type of organic waste liquid, but long residence times are required if the particulate solids in the waste liquid are large or heterogeneous.

In general, the residence time of the anaerobic digestion tank is about 20 to 30 days, but when the organic waste liquid is liquefied, the reaction rate may be increased to shorten the residence time for treatment. Various methods can be used for the liquefaction of such solids (eg, using chemicals, mechanically grinding, using ultrasonics, high temperature treatment, using thermophilic microorganisms, or using an oxidizing agent such as ozone).

However, the above methods have disadvantages of high energy consumption and low solubilization rate.

On the other hand, in the case of high efficiency anaerobic digestion processes such as the UASB (upflow anaerobic sludge blanket) process, the residence time can be shortened.

In order to solve this problem, a homogenizer is used, and FIGS. 1 and 2 are block diagrams of a wastewater treatment apparatus according to the related art, and a block diagram of the wastewater treatment apparatus shown in FIG. 1 is disclosed in Korean Patent Application Publication No. 10-. 2002-0033779).

The wastewater treatment apparatus shown in FIG. 1 uses an homogenizer 46 to crush surplus sludge in a sewage treatment plant and then perform anaerobic digestion to increase digestion efficiency and methane production rate.

However, the wastewater treatment apparatus shown in FIG. 1 is a surplus sludge generated in the sewage treatment process, but was not crushed through the homogenizer 46 and introduced into the anaerobic digester without solid-liquid separation, and thus, a high efficiency anaerobic technique such as UASB could not be introduced. In particular, primary sludge had a disadvantage in that it takes long time to extinguish by injecting without crushing.

In addition, the block diagram of the wastewater treatment apparatus shown in Figure 2 is a view disclosed in the United States Patent (Registration No .: 6,013,183), the wastewater treatment apparatus shown in Figure 2 introduced a high pressure homogenizer to liquefy the sludge after pH adjustment. .

However, the wastewater treatment apparatus shown in FIG. 2 is treated with anaerobic and aerobic, without high-pressure homogenization and solid-liquid separation, resulting in a decrease in efficiency due to inflow of solids.

That is, the wastewater treatment apparatus according to the related art (FIGS. 1 and 2) has a disadvantage in that 100% liquefaction of the solid is impossible even when the organic waste liquid is crushed and homogenized.

Therefore, even if the homogenization treatment is not possible 100% liquefaction of the solid, there is a problem that can not be applied to a high efficiency anaerobic process such as UASB because the solid concentration is high.

Accordingly, the technical problem to be achieved by the present invention is to provide an organic waste liquid treatment apparatus and an organic waste liquid treatment method capable of increasing the efficiency of the high efficiency anaerobic process.

The organic waste liquid treatment apparatus for achieving the above technical problem, the high pressure homogenizer for crushing and liquefying the solids contained in the organic waste liquid; A solid-liquid separation acid fermentation tank for acid fermenting and solid-liquid separation of the treated water flowing out from the high pressure homogenizer; And it may include a high efficiency anaerobic tank to recover the methane by digesting the organic matter flowing out of the solid-liquid separation acid fermentation tank.

The organic waste liquid treatment apparatus may further include a nutrient recovery tank for recovering nitrogen and phosphorus contained in the treated water flowing out of the high efficiency anaerobic tank.

The nutrient recovery tank can recover the nitrogen and the phosphorus by injecting a Ca component to increase the pH of the treated water flowing out of the high-efficiency anaerobic tank.

The nutrient recovery tank can return the discharged water from which the nitrogen and the phosphorus have been recovered to the solid-liquid separation acid fermentation tank.

The solid-liquid separation acid fermentation tank may convert the dissolved organic matter contained in the treated water flowing out of the high pressure homogenizer into short chain fatty acid (SCFA) having a short carbon length through fermentation.

The high pressure homogenizer may be liquefied by crushing the solids contained in at least one of sludge, livestock manure, and food waste processed in the wastewater treatment apparatus.

Waste water treatment apparatus for achieving the technical problem, the first pre-treatment unit for removing the solid matter contained in the waste water; A first precipitation unit connected to the first pretreatment unit to precipitate the precipitate contained in the pretreated wastewater; A biological reactor for decomposing and removing organic substances by reacting the wastewater introduced by being connected with the primary precipitation unit with microorganisms; A secondary precipitation unit connected to the biological reaction tank to separate the sludge generated from the biological reaction and the treated water; A concentrating unit concentrating the sludge generated by the secondary precipitation unit; A high pressure homogenizer for crushing and liquefying at least one of the sludge concentrated by the concentrating unit and the precipitate precipitated by the primary precipitation unit; A solid-liquid separation acid fermentation tank for acid fermenting and solid-liquid separation of the treated water flowing out from the high pressure homogenizer; And it may include a high efficiency anaerobic tank to recover the methane by digesting the organic matter discharged from the solid-liquid separation acid fermentation tank.

The wastewater treatment apparatus may further include a nutrient recovery tank for recovering nitrogen and phosphorus contained in the treated water flowing out of the high efficiency anaerobic tank.

The nutrient recovery tank can recover the nitrogen and the phosphorus by injecting a Ca component to increase the pH of the treated water flowing out of the high-efficiency anaerobic tank.

The wastewater treatment apparatus includes a second pretreatment unit for removing solid matter contained in organic wastes; And a storage tank for storing the organic waste pretreated by the second pretreatment unit, wherein the organic waste stored by the storage tank is introduced into the high pressure homogenizer and processed.

The organic waste liquid treatment method for achieving the above technical problem, high pressure homogenization step of crushing and liquefying the solids contained in the organic waste liquid; A solid-liquid separation acid fermentation step for acid fermenting and solid-liquid separation of the treated water that has undergone the high pressure homogenization step; And it may include a high efficiency anaerobic step of recovering methane by digesting the organic matter generated by the solid-liquid separation acid fermentation step.

The organic waste liquid treatment method may further include a nutrient recovery step of recovering nitrogen and phosphorus contained in the treated water having undergone the high efficiency anaerobic step.

The nutrient recovery step may recover the nitrogen and the phosphorus by injecting a Ca component to increase the pH of the treated water after the high efficiency anaerobic step.

In the organic waste liquid treatment method, the nitrogen and the phosphorus effluent recovered through the nutrient recovery step may be reprocessed through the solid-liquid separation acid fermentation step.

The high pressure homogenization step may be a step of liquefying by crushing solids contained in at least one of sludge, livestock manure, and food waste processed in a wastewater treatment plant.

Therefore, the organic waste liquid treating apparatus and the organic waste liquid treating method according to the present invention treat organic waste liquor in a high pressure homogenizer, and then, after the solid-liquid separation and acid fermentation are performed, solid organic matter having high biodegradability is produced By introducing into the anaerobic digestion tank has the effect of increasing the efficiency of the high efficiency anaerobic process.

In addition, the organic waste liquid treatment apparatus and the organic waste liquid treatment method according to the present invention can improve the efficiency of the anaerobic digestion process to increase the generation efficiency of carbon gas (CH ₄ ) and recover nitrogen and phosphorus present in a high concentration in the anaerobic digester effluent. Therefore, it can be used effectively as a resource such as fertilizer.

In addition, the organic waste liquid treatment apparatus and the organic waste liquid treatment method according to the present invention by using the high pressure homogenization step and the solid-liquid separation acid fermentation step to allow the organic matter in the liquid phase into the anaerobic digestion tank to maximize the efficiency of the high efficiency anaerobic process residence time It can be minimized.

In addition, the organic waste liquid treatment apparatus and the organic waste liquid treatment method according to the present invention not only increase the recovery rate of the organic matter by returning a part of the effluent water from which organic matter (nitrogen and phosphorus) have been recovered by the nutrient recovery tank to the solid-liquid separation acid fermentation tank, but also anaerobic digestion tank. It can solve ammonia toxicity problem that may occur.

Advantages and features of the present invention, and methods for achieving them will be apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only the embodiments are to make the disclosure of the present invention complete, and those skilled in the art to which the present invention pertains. It is provided to fully inform the scope of the invention, and the invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

3 is a block diagram of a wastewater treatment apparatus according to an embodiment of the present invention. Referring to FIG. 3, the wastewater treatment apparatus 100 includes a first pretreatment unit 112, a primary precipitation unit 114, a biological reactor 116, a secondary precipitation unit 124, a concentration unit 126, and a first pretreatment unit 112. 2 may include a pretreatment unit 128, a storage tank 130, and an organic waste liquid processing apparatus 131.

The wastewater flowing into the wastewater treatment apparatus 100 described in detail below may include at least one of livestock manure, food waste, and sewage sludge.

The first pretreatment unit 112 may remove the solid material contained in the wastewater. In more detail, the first pretreatment unit 112 may remove solids (eg, sand) included in the wastewater by using a screen, a fine screen, a drum screen, a settler, and a combination thereof. Can be.

The primary precipitation unit 114 may be connected to the first pretreatment unit to precipitate the precipitate contained in the pretreated wastewater. At this time, the primary precipitation unit 114 may be implemented as a slope plate precipitation tank.

Inclined plate sedimentation tank is a device that improves the water quality by sedimentation of suspended matter heavier than water by gravity. In general, sedimentation of single particles in a gradient plate settling tank is known to be directly related to the settling rate, regardless of the depth of the tank. In order to optimize the flotation removal efficiency of the settling tank, the surface area of the settling tank should be properly designed as much as possible.

Inclined plate sedimentation tank is widely used because of the excellent precipitation effect of the suspended solids based on the above analysis. This inclined plate settling tank is used to form a multi-layered inclined tube (sedimentation channel) using the inclined plate in the settling tank to increase the settling efficiency. As the inclined plate settling tank is formed by the inclined tube (sedimentation channel) by the multi-layered inclined plate, the overall settling distance can be kept short, so that the settling process can be speeded up, and in addition, there is an advantage in discharge of the sediment required for the settling process.

The biological reactor 116 may decompose and remove organic matter by reacting the incoming wastewater with microorganisms.

The biological reaction means 116 may include a combination of reaction tanks, such as an anaerobic tank 118, an anaerobic tank 120, and an aerobic tank 122, and although not shown in view of decomposition efficiency of organic matter, residence time, etc. 120), an aerobic tank 122, etc. can also be contained in multiple numbers.

Phosphorus release may occur in the anaerobic tank 118 of the biological reaction means 116. In the anaerobic tank 120 adjacent to the anaerobic tank 118 described above, nitrous acid and nitric acid in the wastewater may be converted to and removed from nitrogen gas using denitrifying microorganisms.

In the aerobic tank 122 adjacent to the anoxic tank 120, organic matter in the wastewater can be decomposed into carbon dioxide and water using aerobic microorganisms, and ammonia nitrogen can be nitridated to nitrous acid or nitric acid using nitric oxide microorganisms.

 The secondary precipitation unit 124 may be connected to the biological reactor 116 to separate the sludge and the treated water generated by the biological reaction. For example, the secondary precipitation unit 124 may precipitate the sludge produced by the biological reaction and outflow the treated water.

The concentration unit 126 may concentrate the sludge generated by the secondary precipitation unit 124, the second pretreatment unit 128 may remove the solid material contained in the organic waste. More specifically, the second pretreatment unit 128 removes solid matter (eg, sand, etc.) included in the organic waste by using a screen, a fine screen, a drum screen, a sedimentation basin, and a combination thereof. can do.

The storage tank 130 may store the organic waste pretreated by the second pretreatment unit 128. For example, the storage tank 130 may store the organic waste pretreated by the second pretreatment unit 128 to adjust the flow rate of the organic waste flowing into the high pressure homogenizer 132.

The organic waste liquid processing apparatus 131 crushes at least one of sludge concentrated by the concentrating unit 126, organic waste flowing out of the storage tank 130, and generated sediment precipitated by the primary sedimentation unit 114. Liquid liquefied, and the liquid liquefied by acid fermentation to separate the solid-liquid and digest the organic matter generated by the acid fermentation and solid-liquid separation to recover the methane, and recover the nitrogen and phosphorus contained in the treated water recovered methane. have.

The organic waste liquid processing apparatus 131 may include a high pressure homogenizer 132, a solid-liquid separation acid fermentation tank 134, a high efficiency anaerobic tank 136, and a nutrient recovery tank 138.

The high pressure homogenizer 132 crushes at least one of the sludge concentrated by the concentrating unit 126, the organic waste flowing out of the storage tank 130, and the generated precipitate precipitated by the primary precipitation unit 114. Can be liquefied.

The solid-liquid separation acid fermentation tank 134 may acid-ferment and solid-liquid separate the treated water flowing out from the high pressure homogenizer 132. More specifically, the solid-liquid separation acid fermentation tank 134 may convert the dissolved organic matter contained in the treated water flowing out from the high pressure homogenizer 132 into short chain fatty acid (SCFA) having a short carbon length through fermentation. have.

For example, the solid-liquid separation acid fermentation tank 134 may convert the organic matter contained in the high pressure homogenizer 132 into a dissolved state through acid fermentation and perform solid-liquid separation through precipitation.

The solid-liquid separation acid fermentation tank 134 may convert the organic material present in the solid form into a dissolved organic material through hydrolysis and acid production steps. At this time, the treated water introduced into the solid-liquid separation acid fermentation tank 134 which is operated in an unstirred manner may be solidified and accumulated for a predetermined time while undergoing acid fermentation.

That is, the solid-liquid separation acid fermentation tank 134 may flow only organic matter in a liquid state into the high-efficiency anaerobic tank 136.

The high efficiency anaerobic tank 136 may recover the methane (CH ₄ ) and / or carbon dioxide (CO ₂ ) by digesting the organic matter discharged from the solid-liquid separation acid fermentation tank 134. At this time, methane (CH ₄ ) recovered by the high efficiency anaerobic tank 136 may be used for power generation.

At this time, the high efficiency anaerobic tank 136 may be implemented as a high efficiency anaerobic tank in the form of upflow anaerobic sludge blanket (UASB).

The nutrient recovery tank 138 may recover nitrogen and phosphorus contained in the treated water flowing out of the high efficiency anaerobic tank 136. For example, the nutrient recovery tank 138 may recover the nitrogen and the phosphorus by injecting a Ca component to increase the pH of the treated water flowing out of the high-efficiency anaerobic tank 136.

On the other hand, if there is an excessive ammonia concentration (3,000mg / L or more) in the high-efficiency anaerobic tank 136, the anaerobic digestion efficiency is reduced by ammonia toxicity. In order to solve such a problem, according to an embodiment of the present invention, the nutrient recovery tank 138 may return a portion of the discharged water from which nitrogen and phosphorus have been recovered to the solid-liquid separation acid fermentation tank 134.

That is, the nutrient recovery tank 138 of the organic waste liquid treatment apparatus 131 according to the embodiment of the present invention can increase the recovery rate of organic matter by returning the discharged water in which nitrogen and phosphorus are recovered to the solid-liquid separation acid fermentation tank 134. In addition, there is an effect that can solve the ammonia toxicity problem that may occur in the high efficiency anaerobic tank (136).

4 is a flowchart showing an organic waste liquid treatment method according to the present invention. 3 and 4, the high pressure homogenizer 132 may be liquefied by crushing the solids contained in the organic waste liquid (S11), solid-liquid separation acid fermentation tank 134 acid acid treatment water that passed through step S 11 Fermentation and solids can be separated (S13).

High-efficiency anaerobic tank 136 can recover the methane by digesting the organic matter generated by step S13 (S15), nutrient recovery tank 138 to recover nitrogen and phosphorus contained in the treated water after the step S15. Can be.

In the above described exemplary embodiments of the present invention by way of example, the scope of the present invention is not limited to the specific embodiments as described above, the patent of the present invention by those skilled in the art to which the present invention belongs Changes may be made as appropriate within the scope of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS In order to better understand the drawings cited in the detailed description of the invention, a brief description of each drawing is provided.

1 is a block diagram of a wastewater treatment apparatus according to the related art.

2 is a block diagram of a wastewater treatment apparatus according to the related art.

3 is a block diagram of a wastewater treatment apparatus including an organic wastewater treatment apparatus according to the present invention.

4 is a flowchart showing an organic waste liquid treatment method according to the present invention.

Claims (15)

A high pressure homogenizer for crushing and liquefying the solids contained in the organic waste liquid; A solid-liquid separation acid fermentation tank for acid fermenting and solid-liquid separation of the treated water flowing out from the high pressure homogenizer; And Organic waste liquid processing apparatus comprising a high-efficiency anaerobic tank for recovering methane by digesting the organic matter flowing out of the solid-liquid separation acid fermentation tank. According to claim 1, The organic waste liquid treatment apparatus, Organic waste liquid processing apparatus further comprises a nutrient recovery tank for recovering nitrogen and phosphorus contained in the treated water flowing out of the high efficiency anaerobic tank. The nutrient recovery tank of claim 2, An organic waste liquid processing apparatus for recovering the nitrogen and the phosphorus by injecting a Ca component to raise the pH of the treated water flowing out of the high-efficiency anaerobic tank. The nutrient recovery tank of claim 2, An organic waste liquid processing apparatus for returning the discharged water from which the nitrogen and the phosphorus have been recovered to the solid-liquid separation acid fermentation tank. According to claim 1, The solid-liquid separation acid fermentation tank, The organic waste solution treatment apparatus for converting the dissolved organic matter contained in the treated water flowing out from the high pressure homogenizer to short chain fatty acid (SCFA) of short carbon length through fermentation. According to claim 1, wherein the high pressure homogenizer, An organic waste liquid treating apparatus for crushing and liquefying solids contained in at least one of sludge, livestock waste, and food waste treated in a wastewater treatment apparatus. A first pretreatment unit for removing the solid matter contained in the waste water; A first precipitation unit connected to the first pretreatment unit to precipitate the precipitate contained in the pretreated wastewater; A biological reactor for decomposing and removing organic substances by reacting the wastewater introduced by being connected with the primary precipitation unit with microorganisms; A secondary precipitation unit connected to the biological reaction tank to separate the sludge generated from the biological reaction and the treated water; A concentrating unit concentrating the sludge generated by the secondary precipitation unit; A high pressure homogenizer for crushing and liquefying at least one of the sludge concentrated by the concentrating unit and the precipitate precipitated by the primary precipitation unit; A solid-liquid separation acid fermentation tank for acid fermenting and solid-liquid separation of the treated water flowing out from the high pressure homogenizer; And Wastewater treatment apparatus comprising a high-efficiency anaerobic tank for recovering methane by digesting the organic matter discharged from the solid-liquid separation acid fermentation tank. The wastewater treatment apparatus of claim 7, Wastewater treatment apparatus further comprising a nutrient recovery tank for recovering nitrogen and phosphorus contained in the treated water outflow from the high efficiency anaerobic tank. The method of claim 8, wherein the nutrient recovery tank, A wastewater treatment apparatus for recovering the nitrogen and the phosphorus by injecting a Ca component to increase the pH of the treated water flowing out of the high-efficiency anaerobic tank. The wastewater treatment apparatus of claim 7, A second pretreatment unit for removing the solid material contained in the organic waste; And Further comprising a storage tank for storing the organic waste pretreated by the second pre-treatment unit, wherein the organic waste stored by the storage tank, Waste water treatment apparatus is introduced into the high pressure homogenizer and treated. A high pressure homogenization step of crushing and liquefying the solids contained in the organic waste liquid; A solid-liquid separation acid fermentation step for acid fermenting and solid-liquid separation of the treated water that has undergone the high pressure homogenization step; And Organic waste liquid treatment method comprising a high efficiency anaerobic step of recovering methane by digesting the organic matter generated by the solid-liquid separation acid fermentation step. The method of claim 11, wherein the organic waste liquid treatment method, Organic waste solution treatment method further comprising a nutrient recovery step of recovering nitrogen and phosphorus contained in the treated water undergoing the high efficiency anaerobic step. The method of claim 12, wherein the nutrient recovery step, An organic waste liquid treatment method for recovering the nitrogen and the phosphorus by injecting a Ca component to increase the pH of the treated water that has undergone the high-efficiency anaerobic step. The method of claim 12, wherein the organic waste liquid treatment method, The organic waste liquid treatment method for reprocessing the discharged water from the nitrogen and the phosphorus recovered through the nutrient recovery step through the solid-liquid separation acid fermentation step. The method of claim 11, wherein the high pressure homogenization step, Organic waste liquid treatment method comprising the step of crushing and liquefying the solids contained in at least one of the sludge, livestock waste, and food waste treated in the waste water treatment plant.

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