KR20100103127A - Advanced wastewater treatment method and system using phosphorous release reactor, rbdcod recovery and crystallization technique for sludge reduction - Google Patents

Abstract

PURPOSE: A method and a system for processing wastewater is provided to reduce a cost for processing sludge, which is generated from the system, by decomposing and utilizing the sludge. CONSTITUTION: Phosphorus contained in sludge, which is transferred from a wastewater processing system to a phosphorous releasing reactor, is discharged as orthophosphoric acid. Ozone and alkaline are introduced into the sludge without the orthophosphoric acid and the sludge is utilized and reduced. The sludge is concentrated and is separated from an ozone contact bath. The concentrated sludge is decomposed as ammoniacal nitrogen and orthophosphoric acid. Remained solution is transferred to a crystallization bath to generate a crystallization material.

Description

Advanced wastewater treatment method and system using phosphorous release reactor, RBDCOD recovery and crystallization technique for sludge reduction}

The present invention relates to a method and a system for advanced wastewater treatment, and more particularly, to a method and a system for advanced wastewater treatment for sludge reduction, organic matter (RBDCOD) recovery, and production of crystallized useful materials.

In general, sludge is a by-product of the process of decomposing and treating pollutants in sewage water. The main component consists of high concentrations of organic matter and nutrients. Only when the sludge has been disposed of finally can the sewage treatment be completed.

Among them, nutrients are composed of inorganic elements including nitrogen and phosphorus, which flow into rivers or coastal seas and promote algae growth, causing eutrophication and red tide. Therefore, these nutrients are substances to be removed before they enter rivers or coastal waters.

A common method of treating sludge is to land the sludge cake by-product through the steps of concentration, digestion, dehydration, drying and incineration.

Looking at environmental changes at home and abroad, the Convention seeks to effectively control all marine sources and to prevent marine pollution from the discharge of waste and other substances. In Korea, as the London Protocol 96 Protocol came into force on March 24, 2006, the seawater discharge standard for organic sludge has been strengthened, and the Ministry of Maritime Affairs and Fisheries has been enacting a ban on sewage sludge, etc. since 2012. The Ministry of Environment is setting a target of 0% ocean emissions at the end of 2011.

Therefore, the company is seeking to reduce sewage sludge, secure source technology to recover useful resources, and develop a sludge reduction advanced treatment system (MBR, BNR) combination process. Therefore, in the long run, the company is seeking to develop sludge-free sewage treatment technology for sludge reduction and recycling.

An object of the present invention is to reduce the waste sludge generated in the wastewater treatment apparatus and to increase the crystallization efficiency.

In addition, another object of the present invention is to recover the high concentration organic matter (RBDCOD) to increase the nitrogen and phosphorus removal efficiency.

In addition, another object of the present invention is to produce useful materials using waste sludge.

In order to achieve the above object, the present invention is a first step of releasing the phosphorus contained in the waste sludge transported to the phosphorus discharge tank in the wastewater advanced treatment apparatus to the purified phosphoric acid, the waste sludge discharged from the phosphorus discharge tank in the ozone contact tank In the second step of solubilizing and reducing the solubilization by simultaneously injecting ozone and alkali, the waste sludge solubilized and reduced in the ozone contact tank is concentrated and solid-liquid separated in a fermentation concentrate tank, and the anaerobic fermentation of the concentrated waste sludge is carried out to ammonia nitrogen and phosphorous acid. A third step of decomposing to the fourth step of transferring the supernatant liquid of the fermentation concentrate tank to a crystallization tank, and the concentrated waste sludge is transferred to the cited extraction tank again, and the crystallization tank crystallizes the transferred filtrate to generate a crystallized material. In the fifth step, the crystallization tank is a sixth step of recovering the supernatant liquid by separating the crystallized material into a solid-liquid Determining the Garden are to provide a number of the supernatant wastewater advanced treatment method including a seventh step of using as a carbon source and returned to the wastewater treatment device altitude.

The present invention also provides an advanced sewage treatment apparatus for treating sewage water, including anaerobic tank, anoxic tank, and final settler, citation tank for releasing phosphorus contained in waste sludge conveyed from the final settler as fixed phosphoric acid; Ozone contact tank for solubilizing and reducing solubilization by simultaneously injecting ozone and alkali into the used waste sludge, fermentation concentrate tank for concentrating, solid-liquid separation and decomposition of the solubilized and reduced waste sludge in the ozone contact tank, and supernatant from the fermentation concentrate tank, It includes a crystallization tank for crystallizing the supernatant, it provides a wastewater advanced treatment system for the waste sludge concentrated in the fermentation concentration tank is transferred to the cited extraction tank.

The present invention also provides a first step of transporting waste sludge from the wastewater advanced treatment apparatus, and a second step of solubilizing and reducing the ozone and alkali by simultaneously injecting ozone and alkali from the ozone contact bath, and the ozone contact bath. The waste sludge reduced in the third step is stored in a storage tank and supplied to a mechanical concentrator, and the waste sludge is concentrated at a high concentration in the mechanical concentrator, and the filtrate generated in the mechanical concentrator is introduced into a crystallization tank and concentrated. The sludge is introduced into a fermentation tank, and the crystallization tank is a fifth step of crystallizing the introduced filtrate to produce a crystallized product, and a sixth step of recovering the supernatant liquid by solid-liquid separation of the crystallized product from the settling tank; The wastewater comprising the seventh step of returning the supernatant liquid recovered from the sedimentation tank to the sewage wastewater treatment system as a carbon source. It provides around the Lee way.

The present invention also provides a first step in which the waste sludge is transported in the membrane separation tank of the wastewater treatment apparatus, and the second step of solubilizing and reducing the ozone and alkali by simultaneously injecting ozone and alkali from the ozone contact tank; The waste sludge reduced in the ozone contact tank is concentrated and solid-liquid separation in the fermentation concentrate tank, the third step of acid fermentation of the concentrated sludge into ammonia nitrogen and phosphorous acid, and the filtrate generated in the fermentation concentrate tank A fourth step of flowing into a crystallization tank to crystallize the filtrate to produce a crystallization, a fifth step of recovering the supernatant liquid by separating the crystallization liquid from the settling tank, and the supernatant liquid recovered from the sedimentation tank for treating the wastewater. Provided is a high wastewater treatment method comprising the sixth step to return to the carbon source.

The present invention also provides an advanced wastewater treatment apparatus for treating wastewater including an aerobic tank, an ozone contacting tank for solubilizing and reducing ozone and alkali by simultaneously injecting ozone and alkali from waste sludge transferred from the advanced wastewater treatment system, and in the ozone contacting tank. A storage tank for storing the reduced waste sludge and supplying it to a mechanical concentrator, a mechanical concentrator for concentrating the waste sludge supplied from the storage tank at a high concentration, and a fermentation tank into which the sludge concentrated at a high concentration in the mechanical concentrator is introduced. And a crystallization tank into which the filtrate generated in the mechanical concentrator is introduced, crystallizing the filtrate to produce a crystallization, and a precipitation tank for solidifying the crystallization to recover the supernatant.

The present invention also provides a wastewater treatment apparatus for treating wastewater including a membrane separation aeration tank, an ozone contacting tank for solubilizing and reducing ozone and alkali by simultaneously injecting ozone and alkali from waste sludge transferred from the wastewater treatment apparatus, and in the ozone contacting tank. A fermentation concentrator for concentrating, solid-liquid separation, and acid fermentation of the solubilized and reduced waste sludge, a crystallization tank for introducing a filtrate generated in the fermentation concentrator, and crystallizing the filtrate to produce a crystallized product; It provides a high sewage water treatment system comprising a sedimentation tank to recover the supernatant by solid-liquid separation.

The present invention also provides a first step of releasing phosphorus contained in the waste sludge transported to the cited extraction tank in the sewage treatment tank to purified phosphoric acid, and the waste sludge discharged from the cited extraction tank to ozone and alkali in an ozone contact tank. In the second step of solubilizing and reducing by injecting at the same time, the solubilized and reduced waste sludge in the ozone contact tank is concentrated in a high concentration in a mechanical concentrator, and the filtrate generated in the mechanical concentrator is transferred to a crystallization tank and the concentrated waste sludge is A third step of transferring to the quoting tank again, and a fourth step of crystallizing the transferred filtrate to produce a crystallized material, and a precipitation step of collecting the supernatant by solid-liquid separation of the crystallized material. And, a sixth step of returning the supernatant liquid recovered from the sedimentation tank to the sewage wastewater treatment system as a carbon source. It provides a high level wastewater treatment method comprising.

The present invention also provides an advanced wastewater treatment apparatus for treating sewage water including an anaerobic tank and a final settler, a citation tank for releasing phosphorus contained in waste sludge transferred from the final settler as fixed phosphoric acid, and An ozone contact tank for solubilizing and reducing solubilization by simultaneously injecting ozone and alkali into the discharged waste sludge, a mechanical concentrating device for concentrating the solubilized and reduced waste sludge at a high concentration, and a filtrate generated from the mechanical concentrator A crystallization tank flowing into the filtrate to crystallize the filtrate to produce a crystallization material, and a precipitation tank for solid-liquid separation of the crystallization material introduced from the crystallization tank to recover the supernatant, and the waste sludge concentrated in the mechanical concentrator is cited above. Provides an advanced wastewater treatment system for transportation to the tanker.

As described above, the present invention has the effect of reducing the sludge by reducing the sludge by solubilizing the waste sludge generated in the advanced sewage treatment system in ozone contact tank, mechanical concentrator, fermentation tank to reduce the sludge.

In addition, the present invention recovers the supernatant liquid containing a large amount of organic matter (RBDCOD) after separating the crystallization in the crystallization tank and transfer to the advanced wastewater treatment system to use as a carbon source, the C / N and C / P ratio of the influent sewage is low In the case of sewage treatment, the removal efficiency of nitrogen and phosphorus can be increased even without injecting an external carbon source, thereby reducing the chemical cost of supplying the carbon source.

In addition, the present invention by using only CaCl ₂ and MgCl ₂ in the crystallization tank by transferring only the solubilization liquid separated from the ozone contact tank, the purity of the stubite and hydroxyapatite crystallization can be recycled as a fertilizer It has an effect.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, in describing the embodiments, descriptions of technical contents that are well known in the technical field to which the present invention pertains and are not directly related to the present invention are omitted. This is to more clearly communicate without obscure the core of the present invention by omitting unnecessary description.

First embodiment

1 is a flow chart according to the advanced wastewater treatment method according to the first embodiment of the present invention. 2 is a block diagram showing the main configuration of the advanced sewage water treatment system according to a first embodiment of the present invention.

Before the step S11 is performed, the influent (wastewater) is introduced into the anaerobic or anaerobic tank of the advanced wastewater treatment system 10, and the wastewater transported by the metabolism of the microorganisms is treated appropriately and the microorganisms grow accordingly, thereby surplus sludge. Will occur. The excess sludge generated in this way should be disposed of a certain amount in order to properly maintain the sewage wastewater treatment system 10, and the excess sludge to be discarded is called waste sludge. The waste sludge is drawn from the final settler of the sewage treatment system 10 and is transferred to the citation tank 16.

Subsequently, in step S11, the citation tank 16 allows the phosphorus present in the waste sludge transferred from the final settling of the sewage treatment system 10 to be released into the microorganisms in vitro. That is, the citation tank 16 maximizes the release of phosphorus present in the microorganisms to the phosphorous acid required for crystallization while maintaining anaerobic conditions.

Subsequently, in step S22, the ozone contact tank 18 simultaneously injects ozone and alkali into the waste sludge from which the phosphate is released in the cited extraction tank 16 to solubilize and reduce the waste sludge, and to solubilize the solubilized liquid as the result of solubilization and reduction. Transfer to mechanical concentrator 19. The reason why ozone and alkali injection into the waste sludge is simultaneously performed in the ozone contact tank 18 is that the method of simultaneously applying ozone and alkali into the reaction tank compared with the method of ozone treatment after alkali treatment reduces the reduction efficiency and solubilization efficiency. Is almost the same, and because the sludge can be treated in one reactor, the installation cost and maintenance of the facility are excellent. As shown in FIG. 3, the alkali subsequent ozonation process (hereinafter referred to as continuous treatment) and the ozone and alkali simultaneous treatment process (hereinafter referred to as simultaneous treatment) have similar reduction efficiency and solubilization rate of the waste sludge. However, in terms of maintenance and management of sewage water treatment facilities, simultaneous treatment facilities are considered to be superior to continuous treatment facilities. In addition, as shown in FIG. 4, phosphorus is effectively eluted in the case of the continuous treatment and the simultaneous treatment, but the PO₄-P / STP ratio is low, which shows a limitation in applying the crystallization technique, whereas in the simultaneous treatment, the PO₄-P / STP ratio is relatively As a result, high crystallization efficiency can be expected.

As the injection amount of ozone increases as shown in FIG. 5, PO₄-P does not increase, but AHP (Acid hydrolyzable phosphorous) increases, so that the PO₄-P / STP ratio is increased in order to increase the PO₄-P / STP ratio. ), It was necessary to add citation tank (16, anaerobic reactor).

Referring to the result of adding the citation tank 16 in Figure 6, it can be seen that after adding the citation tank 16 to the sewage treatment system 10, the PO₄-P / STP ratio significantly increased.

In addition, the ozone contacting tank 18 is composed of polysaccharides such as peptidoglycan and chemically destroys the cell walls of microorganisms that are difficult to degrade. Thus, solubilization and reduction of the waste sludge is carried out, and the pH at this time is automatically adjusted by a pH automatic control device using NaOH to 10.5.

Subsequently, in step S33, the mechanical concentrator 19 concentrates the solubilized and reduced waste sludge (solubilized liquid) transferred from the ozone contact tank 18 to a high concentration, and the filtrate generated during the solubilized and reduced waste sludge concentration is The waste sludge (concentrated solubilizing liquid) introduced into the crystallization tank 20 is introduced into the cited extraction tank 16, and some concentrated waste sludge is discarded. The concentrated waste sludge conveyed to the citation tank 16 is waste sludge concentrated in a mechanical concentrator 19 containing a large amount of degradable organic matter (RBDCOD) generated by ozone and alkali pretreatment. The quotation citation 16 performs the above processes again from step S110.

Subsequently, in step S44, the crystallization tank 20 forms the ammonia and phosphorus contained in the filtrate transferred from the mechanical concentrator 19 by using CaCl ₂ and MgCl ₂ in the form of stuvite and hydroxyapatite. Crystallization (crystallization). At this time, the crystallization material in the form of stuvite and hydroxyapatite is used as a raw material of by-product fertilizer or phosphate fertilizer.

Subsequently, in step S55, the precipitation tank 21 performs solid-liquid separation of the crystallized material to recover the supernatant (high quality organic material from which ammonia and phosphorus are removed). In step S66, the settling tank 21 returns the recovered supernatant to the wastewater advanced treatment apparatus 10, and the wastewater advanced treatment apparatus 10 uses the recovered supernatant as a carbon source. At this time, the supernatant may be supplied to the advanced wastewater treatment system 10 to be used to increase the removal efficiency of nitrogen and phosphorus in the advanced treatment process.

Second embodiment

7 is a configuration diagram showing the main configuration of the advanced sewage water treatment system for treating sewage water according to a second embodiment of the present invention. Referring to Fig. 7, the main configuration and the function of each configuration of the advanced wastewater treatment system 10 for treating the wastewater are the same as the main configuration and the function of each configuration described in Fig. 2. However, in FIG. 7, the separation membrane 22 is added to the crystallization tank 20 instead of the precipitation tank 21. Separation membrane 22 performs the solid-liquid separation in the settling tank 21 in the crystallization tank 20 to completely remove the solids to recover the high-quality supernatant.

Third embodiment

The wastewater treatment system and method according to the third embodiment of the present invention will be described with reference to FIGS. 8 and 9. In step S110, the waste sludge is transferred to the ozone contact tank 18 from the aerobic tank of the sewage treatment system 10. At this time, the waste sludge conveyed from the aerobic tank is preferably sludge containing a large amount of phosphorus in the microbial cells by the excessive intake of phosphorus by the microorganisms.

Subsequently, in step S220, the ozone contacting tank 18 injects ozone and alkali into the waste sludge transferred from the aerobic tank of the sewage treatment system to simultaneously solubilize and reduce the waste sludge. And solubilized and reduced waste sludge in the ozone contact tank 18 is introduced into the storage tank (31). In the ozone contact tank 18, by simultaneously injecting alkali and ozone into the waste sludge, solubilizing and reducing the cell wall of microorganisms, which are composed of polysaccharides such as peptidoglycan and are not easily degraded, are chemically destroyed. In addition, the pH of the waste sludge at this time is automatically adjusted to 10.5 by a pH automatic control device using NaOH. In addition, the ozone contact tank 18 can inject ozone from the ozone generator 17 into the waste sludge.

Subsequently, in step S330, the storage tank 31 stores the solubilized and reduced waste sludge introduced from the ozone contact tank 18, and stably supplies the stored waste sludge to the mechanical concentrator 19.

In step S440, the mechanical concentrator 19 concentrates the waste sludge supplied from the storage tank 31 to a high concentration. The filtrate generated at the time of concentration in the mechanical concentration device 19 is introduced into the crystallization tank 20, and the concentrated waste sludge concentrated at a high concentration is introduced into the fermentation tank 32.

Subsequently, the fermentation tank 32 is acid-fermented from the concentrated waste sludge introduced from the mechanical concentrator 19, and the ammonia nitrogen and the nitrogen needed to crystallize the organic nitrogen and organophosphorus that affect the crystallization efficiency in the crystallization tank 20. Decompose with regular phosphoric acid. For this reason, the crystallization efficiency performed in the crystallization tank 20 can be improved. More specifically, ammonia nitrogen, which is a substance required for crystallization, of cellular internal substances eluted in cells due to cell wall destruction of microorganisms in ozone contact tank 18 during crystallization of stubite and hydroxyapatite in crystallization tank 20. This is because most of the organic nitrogen and organic phosphorus is not in the form of phosphorous acid. In addition, in the fermentation tank 32, it is possible to perform further reduction of the waste sludge with a high concentration of degradable organic material (RBDCOD) produced by decomposing waste sludge which is not solubilized in the ozone contact tank 18.

In the crystallization tank 20, the pH decrease occurs due to the influence of volatile fatty acids, which are decomposable organic substances generated during the acid fermentation process in the fermentation tank 32. For this reason, the fermentation tank 32 adjusts the pH again using an automatic pH adjuster to satisfy the conditions of 9.5-10.7, which is an optimal pH for the formation of stubite and hydroxyapatite crystallization.

Subsequently, in step S550, the crystallization tank 20 crystallizes from the filtrate introduced from the mechanical concentrator 19. To this end, the crystallization tank 20 uses CaCl ₂ and MgCl ₂ to crystallize ammonia and phosphorus contained in the introduced filtrate in the form of sturtite and hydroxyapatite.

Thereafter, the crystallization tank 20 in step S660 is solid-liquid separation of the crystallized crystallized in step S550 to recover the supernatant (high quality organic material from which ammonia and phosphorus are removed). As a result of solid-liquid separation, the crystallized product is separated into stubbit and hydroxyapatite and supernatant. At this time, the stubbite and hydroxyapatite may be used as a raw material of by-product fertilizer or phosphate fertilizer.

Subsequently, in step S770, the crystallization tank 20 returns the collected supernatant to the wastewater advanced treatment apparatus 10, and the wastewater advanced treatment apparatus 10 uses the returned supernatant as a carbon source. At this time, the supernatant is supplied to the advanced sewage treatment system and used to increase the efficiency of nitrogen and phosphorus removal in the advanced treatment process.

Fourth embodiment

10 is a block diagram showing the main configuration of the advanced sewage water treatment system for treating sewage water according to a fourth embodiment of the present invention. Referring to FIG. 10, the main configuration and the functions of each configuration of the advanced sewage water treatment system 10 for treating the wastewater are the same as those of the main configuration and each configuration described in FIG. However, in FIG. 10, the separation membrane 22 is added to the crystallization tank 20 instead of the precipitation tank 21. Separation membrane 22 performs the solid-liquid separation in the settling tank 21 in the crystallization tank 20 to completely remove the solids to recover the high-quality supernatant.

Fifth Embodiment

The wastewater treatment system and method according to the fifth embodiment of the present invention will be described with reference to FIGS. 11 and 12. Inflow step (wastewater) in step S111 is introduced into the anaerobic tank or anaerobic tank of the advanced wastewater treatment system 10 is drawn from the final settler. The drawn waste sludge is conveyed to the ozone contact tank 18.

Thereafter, in step S222, the ozone contact tank 18 injects ozone and alkali into the waste sludge transferred from the membrane separation aeration tank 15 to perform solubilization and reduction of the waste sludge. And solubilized and reduced waste sludge in the ozone contact tank 18 is introduced into the fermentation concentration tank (23). In the ozone contact tank 18, by simultaneously injecting alkali and ozone into the waste sludge, solubilizing and reducing the cell wall of microorganisms, which are composed of polysaccharides such as peptidoglycan and are not easily degraded, are chemically destroyed. In addition, the pH of the waste sludge at this time is automatically adjusted to 10.5 by a pH automatic control device using NaOH. In addition, the ozone contact tank 18 can inject ozone from the ozone generator 17 into the waste sludge.

Subsequently, in step S333, the fermentation concentration tank 23 is enriched with sludge and solid-liquid separation, and is subjected to an acid fermentation process. Decomposition improves the crystallization efficiency. For this reason, the crystallization efficiency performed in the crystallization tank 20 can be improved. More specifically, ammonia nitrogen, which is a substance required for crystallization, of cellular internal substances eluted in cells due to cell wall destruction of microorganisms in ozone contact tank 18 during crystallization of stubite and hydroxyapatite in crystallization tank 20. This is because most of the organic nitrogen and organic phosphorus is not in the form of phosphorous acid. In addition, in the fermentation concentration tank 23, it is possible to perform further reduction of the waste sludge with a high concentration of degradable organic material (RBDCOD) produced by decomposing waste sludge which is not solubilized in the ozone contact tank 18.

In the crystallization tank 20, a pH decrease occurs due to the influence of volatile fatty acids, which are decomposable organic substances generated during the acid fermentation in the fermentation concentration tank 23. For this reason, the crystallization tank 20 adjusts the pH again using an automatic pH adjusting device to satisfy the conditions of 9.5-10.7, which is an optimal pH for the formation of stubite and hydroxyapatite crystallization.

Subsequently, the filtrate generated in the fermentation concentration tank 23 in step S444 is introduced into the crystallization tank 20 to crystallize.

Subsequently, in step S555, the sedimentation tank 21 is solid-liquid separated to recover the supernatant (high quality organic material from which ammonia and phosphorus are removed). As a result of solid-liquid separation, the crystallized product is separated into stubbit and hydroxyapatite and supernatant. At this time, the stubbite and hydroxyapatite may be used as a raw material of by-product fertilizer or phosphate fertilizer.

Subsequently, in step S666, the crystallization tank 20 returns the recovered supernatant to the sewage treatment apparatus 40 that combines the separator, and the sewage treatment apparatus 40 that combines the separator uses the returned supernatant as a carbon source. At this time, the supernatant is supplied to the wastewater advanced treatment device 40 combined with the separator is utilized to increase the nitrogen and phosphorus removal efficiency of the advanced treatment process.

Sixth embodiment

13 is a block diagram showing the main configuration of the advanced sewage water treatment system for treating sewage water according to a sixth embodiment of the present invention.

Referring to Fig. 13, the main configuration and the functions of each configuration of the advanced wastewater treatment system for treating the wastewater are the same as those of the main configuration and each configuration described in Fig.12. However, in FIG. 13, a separation membrane 22 is added to the crystallization tank 20 instead of the precipitation tank 21. Separation membrane 22 performs the solid-liquid separation in the settling tank 21 in the crystallization tank 20 to completely remove the solids to recover the high-quality supernatant. At this time, in order to reduce the crystallization efficiency due to the growth of microorganisms in the crystallization tank 20 and to prevent membrane contamination, a part of the ozone or the ozone supplied to the ozone contacting tank is supplied into the crystallization tank 20.

Seventh embodiment

A wastewater treatment system and method according to a seventh embodiment of the present invention will be described with reference to FIGS. 14 and 15. Before the step S112 is performed, the influent (wastewater) is introduced into the anaerobic tank or anoxic tank of the advanced wastewater treatment system 10 and the waste sludge drawn from the final settler is transferred to the citation tank 16.

Meanwhile, as the advanced wastewater treatment system, the advanced wastewater treatment system 40 using the KSMBR process may be used.

Subsequently, in step S112, the citation tank 16 allows the phosphorus present in the waste sludge transferred from the final settler of the wastewater advanced processing apparatus 10 to be discharged. That is, the citation tank 16 maximizes the release of phosphorus present in the microorganisms to the phosphorous acid required for crystallization while maintaining anaerobic conditions.

Subsequently, in step S223, the ozone contact bath 18 solubilizes and reduces the waste sludge by simultaneously injecting ozone and alkali into the waste sludge from which the phosphorus acid is discharged in the cited extraction tank 16, and the solubilizing solution that is the result of solubilization and reduced weight. Transfer to the fermentation concentration tank (23). The reason why ozone and alkali injection into the waste sludge is simultaneously performed in the ozone contact tank 18 is that the method of simultaneously applying ozone and alkali into the reaction tank in comparison with the ozone treatment after alkali treatment reduces the reduction efficiency and solubilization efficiency. This is because the waste sludge can be treated in one reactor and the facility installation cost and maintenance are excellent.

In order to increase the PO₄-P / STP ratio, a cited extraction tank (16, anaerobic reactor) was added to the wastewater advanced treatment apparatus 10. In addition, the ozone contacting tank 18 is composed of polysaccharides such as peptidoglycan and chemically destroys the cell walls of microorganisms that are difficult to degrade. Thus, solubilization and reduction of the waste sludge is carried out, and the pH at this time is automatically adjusted by a pH automatic control device using NaOH to 10.5.

Subsequently, in step S334, the fermentation concentration tank 23 concentrates sludge and solid-liquid separation, and undergoes anaerobic acid fermentation to crystallize organic nitrogen and organophosphorus, which are required for crystallization in the crystallization tank. Decomposition to improve the crystallization efficiency.

Subsequently, in step S445, the waste sludge concentrated in the fermentation concentration tank 23 is introduced into the citation extraction tank 16, and the supernatant of the fermentation concentration tank 23 is introduced into the crystallization tank 20, and some concentrated waste sludge is discarded. . The concentrated waste sludge transferred to the citation tank 16 is waste sludge concentrated in the fermentation concentration tank 23 containing a large amount of decomposable organic matter (RBDCOD) generated by ozone and alkali pretreatment. The quotation citation 16 repeats the above processes from step S111.

Thereafter, in step S556, the crystallization tank 20 uses ammonia and phosphorus contained in the supernatant transferred from the fermentation concentrate tank 23 in the form of stuvite and hydroxyapatite using CaCl ₂ and MgCl ₂ . Crystallization. At this time, the crystallization material in the form of struvite and hydroxyapatite is used as a raw material of by-product fertilizer or phosphate fertilizer.

Subsequently, in step S667, the crystallization tank 20 performs solid-liquid separation of the crystallization material to recover the supernatant (high quality organic material from which ammonia and phosphorus are removed). In operation S777, the crystallization tank 20 returns the recovered supernatant to the wastewater advanced treatment apparatus 10, and the wastewater advanced treatment apparatus 10 uses the recovered supernatant as a carbon source. At this time, the supernatant is supplied to the advanced wastewater treatment system 10 is utilized to increase the removal efficiency of nitrogen and phosphorus in the advanced treatment process.

In this case, however, in the crystallization tank 20, the separation filtrate containing the high-quality organic matter without solids may be supplied to the anaerobic tank or the anaerobic tank of the sewage treatment system using the separator 22 to increase the nitrogen and phosphorus removal efficiency of the advanced treatment process. have. In addition, the ozone or ozone supplied to the ozone contact tank 18 is supplied into the crystallization tank 20 in order to reduce crystallization efficiency and prevent membrane contamination due to the growth of microorganisms.

Eighth Embodiment

Meanwhile, the advanced wastewater treatment system according to the seventh embodiment discloses a structure in which a separator is embedded in a crystallization tank, but is not limited thereto. That is, as shown in Figure 16, the advanced sewage water treatment system according to the seventh embodiment includes a crystallization tank 20 without a membrane, and accordingly further comprises a precipitation tank 21. And the wastewater advanced treatment system according to the second embodiment has the same configuration as the wastewater advanced treatment system according to the seventh embodiment except that the crystallization tank 20 and the sedimentation tank are connected, so that the crystallization tank 20 and the sedimentation tank are The connected configuration and the processing method thereof are as follows.

The crystallization tank 20 crystallizes ammonia and phosphorus contained in the filtrate transferred from the fermentation concentration tank 23 in the form of stubite and hydroxyapatite using CaCl ₂ and MgCl ₂ . At this time, the crystallization material in the form of stubite and hydroxyapatite is used as a raw material of by-product fertilizer or phosphate fertilizer.

The precipitation tank 21 recovers the supernatant liquid (high quality organic material from which ammonia nitrogen and phosphorus are removed) by solid-liquid separation of the crystallized material. In step S667, the settling tank 21 returns the recovered supernatant to the advanced wastewater treatment system 10, and the advanced wastewater treatment system 10 uses the recovered supernatant as a carbon source. At this time, the supernatant may be supplied to the advanced wastewater treatment system 10 to be used to increase the removal efficiency of nitrogen and phosphorus in the advanced treatment process.

As described above, the embodiments of the present invention have been described in detail. For those skilled in the art, these specific descriptions are merely preferred embodiments, and the scope of the present invention is not limited thereto. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents.

1 is a flow chart according to the advanced wastewater treatment method according to a first embodiment of the present invention

2 is a configuration diagram showing the main configuration of the advanced sewage water treatment system according to a first embodiment of the present invention

Figure 3 is an exemplary view showing the test results in the ozone contact bath according to the first embodiment of the present invention

4 is an exemplary view showing whether the dissolution of the experimental results of FIG.

5 is an exemplary view showing the dissolution relationship between ozone concentration and AHP, PO₄-P according to the first embodiment of the present invention.

6 is an exemplary view showing a change in phosphorus concentration after adding the citation aid according to the first embodiment of the present invention.

7 is a configuration diagram showing the main configuration of the advanced sewage water treatment system according to a second embodiment of the present invention

8 is a flow chart according to the high wastewater treatment method according to a third embodiment of the present invention

9 is a configuration diagram showing the main configuration of the advanced sewage water treatment system according to a third embodiment of the present invention

10 is a configuration diagram showing the main configuration of the advanced sewage water treatment system according to a fourth embodiment of the present invention

11 is a flow chart according to the advanced wastewater treatment method according to a fifth embodiment of the present invention

12 is a configuration diagram showing the main configuration of the advanced sewage water treatment system according to a fifth embodiment of the present invention

13 is a configuration diagram showing the main configuration of the advanced sewage water treatment system according to a sixth embodiment of the present invention

14 is a flow chart according to the advanced wastewater treatment method according to the seventh embodiment of the present invention

15 is a configuration diagram showing the main configuration of the advanced sewage water treatment system according to a seventh embodiment of the present invention

16 is a block diagram showing the main configuration of the advanced sewage water treatment system for treating sewage water according to an eighth embodiment of the present invention;

Explanation of symbols on the main parts of the drawings

10, 40: Advanced Wastewater Treatment System

11: Anaerobic Tank 12: Dissolved Oxygen Reduction Tank

13: Abandonment Article 3 of Division 3 14: Abandonment Article 3 of Division 3

15: membrane separation aerobic tank 17: ozone generator

18: ozone contact tank 19: mechanical concentrator

20: crystallization tank 21: precipitation tank

22: membrane 23: fermentation concentration tank

31: storage tank 32: fermentation tank

41: pH automatic control device

Claims (20)

A first step of releasing phosphorus contained in the waste sludge transferred to the cited extraction tank into the purified phosphoric acid in the advanced wastewater treatment system; A second step of solubilizing and reducing the waste sludge from which the phosphorus acid is discharged from the cited extraction tank by simultaneously injecting ozone and alkali in an ozone contacting tank; A third step of concentrating and solid-liquid separation of the waste sludge solubilized and reduced in the ozone contact tank and anaerobic fermentation of the concentrated waste sludge into ammonia nitrogen and phosphorous acid; A fourth step of transferring the filtrate generated in the fermentation concentration tank to a crystallization tank and transferring the concentrated waste sludge back to the cited extraction tank; A fifth step of crystallizing the transferred filtrate to produce a crystallization material; The crystallization tank is a sixth step of recovering the supernatant by separating the crystallized material into a solid-liquid; And The crystallization tank is the seventh step of returning the recovered supernatant to the wastewater advanced treatment device to use as a carbon source; Advanced wastewater treatment method comprising a. The method of claim 1, The wastewater advanced treatment method, characterized in that the waste sludge is transferred from the final settler of the advanced wastewater treatment system before the first step to maintain the anaerobic conditions of the cited tank. The method of claim 2, The second step is the advanced wastewater treatment method, characterized in that the ozone contact tank automatically adjusts the pH of the waste sludge in the citation tank by the pH automatic control device using NaOH. The method of claim 3, The third step is the fermentation concentration tank is a step of concentrating the waste sludge containing the degradable organic material (RBDCOD) generated by the ozone and alkali pretreatment transferred from the ozone contact tank to a high concentration and flowing into the cited extraction tank. Advanced wastewater treatment method characterized in that. The method of claim 4, wherein The fifth step is a high wastewater treatment method, characterized in that the crystallization tank readjusted the pH of the sludge fermented in the fermentation concentrate tank. The method of claim 5, The fifth step is a high wastewater treatment method, characterized in that for supplying ozone or ozone supplied to the ozone contact tank into the crystallization tank. The method of claim 6, In the sixth step, if there is a solid in the supernatant liquid recovered from the crystallization tank, the wastewater advanced treatment method, characterized in that for removing the solid using a separator. An advanced wastewater treatment system for treating wastewater, including anaerobic tanks, anoxic tanks, and final settlers (such as anaerobic tanks and anoxic tanks); Citing extraction tank for releasing phosphorus contained in the waste sludge transferred from the final settling to the fixed phosphoric acid; An ozone contact tank for solubilizing and reducing ozone and alkali by simultaneously injecting ozone and alkali into the waste sludge from which the phosphorus acid is released in the cited extraction tank; Fermentation concentration tank for concentrating, solid-liquid separation, decomposition of solubilized and reduced waste sludge in the ozone contact tank; And A crystallization tank into which the supernatant is introduced from the fermentation concentrate and crystallizes the supernatant; And, the waste sludge concentrated in the fermentation concentration tank is transported to the cited extraction tank. The method of claim 8, The citation tank is an advanced sewage water treatment system, characterized in that anaerobic conditions are maintained due to the waste sludge transferred from the final settler. 10. The method of claim 9, The ozone contact tank is an advanced sewage water treatment system, characterized in that for adjusting the pH of the waste sludge conveyed from the cited extraction tank by the automatic pH adjustment device using NaOH. The method of claim 10, The concentrated waste sludge is wastewater, characterized in that the fermentation concentration tank is a waste sludge concentrated in a high concentration of waste sludge containing a decomposable organic substance (RBDCOD) generated by ozone and alkali pretreatment transferred from the ozone contact tank. Advanced processing systems. The method of claim 11, And the crystallization tank readjusts the pH of the sludge fermented in the fermentation concentrate tank. The method of claim 12, And supplying ozone or ozone to the ozone contact tank into a crystallization tank. The method of claim 13, If there is a solid in the supernatant liquid recovered from the crystallization tank, the advanced wastewater treatment system, characterized in that to remove the solid using a separator. Waste sludge is the first step of being transported in the sewage treatment system; A second step of solubilizing and reducing the transported waste sludge by simultaneously injecting ozone and alkali in an ozone contact tank; A third step in which the waste sludge reduced in the ozone contact tank is stored in a storage tank and supplied to a mechanical concentrator; A fourth step in which the waste sludge is concentrated at a high concentration in the mechanical concentrator and the filtrate generated in the mechanical concentrator is introduced into a crystallization tank and the concentrated sludge is introduced into a fermentation tank; The crystallization tank is the fifth step of crystallizing the introduced filtrate to produce a crystallization; A sixth step of recovering the supernatant by solid-liquid separation of the crystalline material in a precipitation tank; A seventh step of returning the supernatant liquid recovered from the sedimentation tank to the sewage water treatment system and using it as a carbon source; Advanced wastewater treatment method comprising a. Waste sludge is transported in the membrane separation tank of the sewage treatment system; A second step of solubilizing and reducing the transported waste sludge by simultaneously injecting ozone and alkali in an ozone contact tank; A third step of the waste sludge reduced in the ozone contact tank is concentrated and solid-liquid separation in a fermentation concentration tank, and the acidic fermentation of the concentrated sludge is decomposed into ammonia nitrogen and regular phosphoric acid; A fourth step of introducing the filtrate generated in the fermentation concentration tank into a crystallization tank and crystallizing the filtrate to produce a crystallized product; A fifth step of recovering the supernatant by solid-liquid separation of the crystalline material in a precipitation tank; A sixth step of returning the supernatant liquid recovered from the sedimentation tank to the sewage treatment system and using it as a carbon source; Advanced wastewater treatment method comprising a. An advanced wastewater treatment system for treating wastewater including an aerobic tank; An ozone contact tank for solubilizing and reducing the waste sludge transported from the advanced wastewater treatment system by simultaneously injecting ozone and alkali; A storage tank for storing the waste sludge reduced in the ozone contact tank and supplying it to a mechanical concentrator; A mechanical concentrating device for concentrating the waste sludge supplied from the storage tank to a high concentration; A fermentation tank into which the sludge concentrated at a high concentration is introduced from the mechanical concentrator; A crystallization tank into which the filtrate generated in the mechanical concentrator is introduced and crystallizes the filtrate to produce a crystallized product; A sedimentation tank for solid-liquid separation of the crystalline material to recover the supernatant; Advanced sewage water treatment system comprising a. A wastewater treatment apparatus for treating wastewater including a membrane separation aeration tank; An ozone contact tank for solubilizing and reducing ozone and alkali by simultaneously injecting waste sludge transferred from the wastewater treatment apparatus; A fermentation concentration tank for concentrating, solid-liquid separation, and acid fermentation of the waste sludge solubilized and reduced in the ozone contact tank; A crystallization tank into which the filtrate generated in the fermentation concentration tank is introduced and crystallizes the filtrate to produce a crystallized product; A sedimentation tank for solid-liquid separation of the crystalline material to recover the supernatant; Advanced sewage water treatment system comprising a. A first step of releasing phosphorus contained in the waste sludge transferred to the cited extraction tank into the purified phosphoric acid in the advanced wastewater treatment system; A second step of solubilizing and reducing the waste sludge from which the phosphorus acid is discharged from the cited extraction tank by simultaneously injecting ozone and alkali in an ozone contacting tank; A third step of concentrating the solubilized and reduced waste sludge in the ozone contact tank at a high concentration in a mechanical concentrator, transferring the filtrate generated in the mechanical concentrator to a crystallization tank, and transferring the concentrated waste sludge to the cited extraction tank again; The crystallization tank is a fourth step of crystallizing the transported filtrate to produce a crystallization material; The precipitation tank is a fifth step of recovering the supernatant liquid by separating the crystallized material into a solid solution; And A sixth step of returning the supernatant liquid recovered from the sedimentation tank to the sewage treatment system and using it as a carbon source; Advanced wastewater treatment method comprising a. Advanced wastewater treatment system for treating wastewater, including anaerobic tanks and final settler; Citing extraction tank for releasing phosphorus contained in the waste sludge transferred from the final settling to the fixed phosphoric acid; An ozone contact tank for solubilizing and reducing ozone and alkali by simultaneously injecting ozone and alkali into the waste sludge from which the phosphorus acid is released in the cited extraction tank; A mechanical concentrating device for concentrating the solubilized and reduced waste sludge in a high concentration in the ozone contact tank; A crystallization tank into which the filtrate generated in the mechanical concentrator is introduced and crystallizes the filtrate to produce a crystallized material; And A precipitation tank for solid-liquid separation of the crystallized material introduced from the crystallization tank to recover the supernatant; And, the waste sludge concentrated in the mechanical concentrator is transferred to the citation tank.

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