KR20150029084A - Sludge solubilization type elutriated two-phase anaerobic digestion apparatus and mixed wastewater treatment method using the same - Google Patents

Abstract

The present invention relates to an elutriation two-phase anaerobic digestion apparatus, which has a solubilizing device (50) installed to solubilize digested sludge discharged from an acid fermenter (10) and re-inputs the digested sludge discharged from the solubilizing device (50) into the acid fermenter (10); and to a wastewater treatment method using the same digestion apparatus, wherein the wastewater treatment method conducts a sequence of treatment processes after mixing sewage sludge, which is generated in a sewage treatment plant, and food wastewater and inputting the same into the acid fermenter (10). According to the present invention, the amount of discharged solids, which are generated in anaerobic digestion, can be minimized, resultingly costs for postprocessing such as concentration, dehydration and carbonization of the solids can be reduced and problems caused by disposal such as reclamation and ocean disposal can be solved fundamentally. In addition, wastewater treatment efficiency can be increased significantly by compensating for the shortcoming of anaerobic digestion of each of sewage sludge having a relatively low content of organic matters and food wastewater having a high content of organic matters but including inhibiting components of anaerobic digestion such as salt.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sludge reprocessing type two-phase anaerobic digestion apparatus and a mixed wastewater treatment method using the same,

The present invention relates to a cleansing type two-phase anaerobic digestion apparatus and a wastewater treatment method using the same, wherein an acid fermentation tank (10) and a methane fermentation tank (30) are connected and a part of a symbol of the methane fermentation tank (30) (50) for solubilizing the digested sludge discharged from the acid fermentation tank (10) is installed, and the digested sludge discharged from the solubilization apparatus (50) is supplied to the anaerobic digester An anaerobic digestion apparatus which minimizes the amount of solid matter discharged by re-entering the fermentation tank (10), and a waste water treatment method using the same digestion apparatus, characterized in that mixed wastewater, which is a mixture of sewage sludge generated from a sewage treatment plant and food wastewater, ), And a wastewater treatment method that maximizes effluent treatment efficiency by performing a series of treatment processes such as acid fermentation, methane fermentation, carrier washing, solubilization and reintroduction of digested sludge All.

Anaerobic digestion is a biological treatment for the stabilization of food wastes, livestock waste, sewage sludge, manure and high concentration organic wastewater. The anaerobic digestion process is an anaerobic digestion method that hydrolyses polymeric organic matter under anaerobic conditions to produce acetic acid, propionic acid acid and butric acid and finally gasifying them into methane, carbon dioxide, ammonia and hydrogen sulfide.

In this anaerobic digestion method, the amount of biological sludge generated per unit organic matter is remarkably smaller than that in the aerobic treatment method, and a considerable proportion of methane that can be fueled in the extinguished gas is discharged. The digested sludge is rich in nitrogen, phosphorous and humus, It has a high merit and is attracting attention as an eco-friendly resource recycling treatment technique that produces fuel and compost as well as a simple waste disposal and disposal function.

As described above, the reaction to be carried out by the anaerobic digestion method can be classified into an acid fermentation reaction for producing volatile fatty acid and a methane fermentation reaction for generating digestion gas such as methane. These acid fermentation and methane fermentation are the same The two-stage anaerobic digester is composed of two reaction tanks and performs the latter method. The two-stage anaerobic digester is a two-phase anaerobic digester.

The two-phase anaerobic digestion system can improve the decomposition efficiency of organic matter compared with a single reaction tank by separately performing acid fermentation and methane fermentation with different reaction rates. Particularly, a part of the treated water discharged from the methane fermentation tank (30) (10) to dissolve the dissolved substances in the digested sludge of the acid fermentation tank (10), thereby maximizing the treatment efficiency. In this way, the extinguishing device to which the treatment water transferring and dissolving function is imparted is called the detoxification two-phase anaerobic digestion device Quot ;, and related art prior art is described in Korean Patent No. 782960.

1, the conventional cleansing type two-phase anaerobic digestion apparatus including the patent No. 782960 includes an acid fermentation tank 10 and a methane fermentation tank 30 for performing acid fermentation and methane fermentation, respectively, and a discharge pipe 15 for connecting the acid fermentation tank 10 and the methane fermentation tank 30, And a conveying pipe 35. [0035]

Organic wastewater initially introduced into the acid fermentation tank 10 is subjected to acid fermentation in the acid fermentation tank 10 so that the treated water floats in the form of supernatant water and the digested sludge is settled to the bottom of the acid fermentation tank 10, The selected number of the collected water is transferred to the methane fermentation tank 30 through the discharge pipe 15 and the digested sludge is discharged to the outside of the acid fermentation tank 10.

The digested gas generated in the methane fermentation process of the treated water flowing into the methane fermentation tank 30 can be collected and converted into a fuel by a separate collecting means, and the number of the decomposed organic matter is discharged or purified in a separate purification facility A part of the treated water discharged from the methane fermentation tank 30 is transferred to the acid fermentation tank 10 through the return pipe 35 to dissolve and dissolve dissolved substances in the digested sludge of the acid fermentation tank 10, It becomes maximized.

The organic biodegradation effect and the digestion efficiency can be improved by using such a cleansing two-phase anaerobic digestion device as compared with the conventional single digestion type digestion device. However, in the operation process, a large amount of digestion sludge, that is, solid waste is generated from the acid fermentation tank In addition, there is a problem that the digestion reaction can not be expected due to lack of organic matter in the sewage sludge during the treatment of the sewage sludge, and the digestion reaction is inhibited by the salt contained in the food wastewater.

In particular, recently, the marine dumping of sludge is totally prohibited. Therefore, it is very urgent to improve the conventional anaerobic digestion apparatus in which a large amount of digested sludge is generated because the land treatment of the sludge generated in the wastewater treatment process is very costly.

An object of the present invention is to provide an anaerobic digestion apparatus for digesting organic wastewater, comprising: an acid fermentation tank (10) in which hydrolysis and acid production reaction of wastewater are carried out; A part of the treated water discharged from the methane fermentation tank 30 is returned to the acid fermentation tank 10 to be dissolved in the digested sludge in the acid fermentation tank 10 The anaerobic digestion apparatus 10 is provided with a vanny tube 16 for discharging the settled digested sludge and a vanny tube 16 for discharging the vanny tube 16 from the acid fermentation tank 10 A solubilization apparatus 50 for solubilizing the digested sludge is connected to the solubilization apparatus 50. The solubilization apparatus 50 in which the digested sludge is stored is provided with a treatment agent inlet 51 for injecting the treatment agent into the digested sludge, Heating to heat the sludge Value 52, the sludge is re-processing type ablution two-phase anaerobic digestion apparatus characterized to be installed.

An inlet pipe 13 is installed at the center of the inside of the acid fermentation tank 10 and connected to the inlet pipe 11 and the solubilization apparatus 50 through which the organic wastewater to be treated is introduced into the upper part of the acid fermentation tank 10, The waste water and digested sludge discharged from the inflow pipe 11 and the reintroduction pipe 12 are introduced into the inlet pipe 13 and the methane fermentation tank 10 is connected to the lower portion of the acid fermentation tank 10 through the reintroduction pipe 12 into which the digested sludge flows, A spraying device 17 in which a plurality of spray holes 18 are perforated as an annular tubular body is provided at the lower side of the acid fermentation tank 10, And the treated water discharged from the methane fermentation tank 30 is sprayed into the acid fermentation tank 10 through the spray hole 18 of the spraying device 17 Is a sludge reprocessing type two-phase anaerobic digestion system.

In the waste water treatment method using the above-described sludge reprocessing type cleansing type two-phase anaerobic digestion apparatus, a mixing step (S10) of mixing sewage sludge and food waste water to form mixed waste water (S10) The acid fermentation tank 10 is fed to the methane fermentation tank 30 and the precipitated digested sludge in the acid fermentation tank 10 is fed to the solubilization apparatus 10, A methane fermentation step S23 for carrying out a methane generation reaction in the methane fermentation tank 30 and a step for returning a part of the supernatant in the methane fermentation tank 30 to the acid fermentation tank 10 (S31) for cleaning and dissolving dissolved substances in the digested sludge, and a reprocessing step (S41) for re-introducing digested sludge solubilized in the solubilization apparatus (50) into the acid fermentation tank (10) A sludge reprocessing type cleansing type 2 phase A mixed type waste water treatment method using the ready-made fire-fighting system.

According to the present invention, solubilization of the non-degradable digestion sludge discharged from the acid fermentation tank 10 and reprocessing the same through the acid fermentation tank 10 can minimize the amount of solid matter generated in the anaerobic digestion process, It is possible to reduce the cost of post-treatment such as concentration, dehydration and carbonization, as well as to fundamentally solve problems caused by disposal through landfill or marine dumping.

In addition, in the treatment of wastewater through anaerobic digestion, the sewage sludge generated from the sewage treatment plant and the food waste wastewater are mixed and treated, whereby the sewage sludge and the organic matter content are relatively poor, and the organic matter content is high, but the inhibition of the anaerobic digestion reaction The disadvantages of the anaerobic digestion process of the food wastewater containing the element can be complemented to improve the effluent treatment efficiency remarkably.

FIG. 1 is a schematic view showing a conventional two-phase anaerobic digestion device
Fig. 2 is a schematic view showing the construction of a wastewater treatment facility to which the present invention is applied
FIG. 3 is a block diagram
Figure 4 is a cut-away perspective view of an excerpt of an embodiment of the acid fermentation tank of the present invention
5 is a flow chart

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2, the apparatus of the present invention includes an acid fermentation tank 10 and a methane fermentation tank 30 for performing acid fermentation and methane fermentation, respectively, A solubilizer 50 for solubilizing the digested sludge generated in the fermentation tank 10, and the like.

A gas storage facility such as a gas holder 72 may be connected to the acid fermentation tank 10 or the methane fermentation tank 30 of the apparatus of the present invention to convert the generated digested gas into fuel and to be finally discharged from the methane fermentation tank 30 The treated water may be sent to another advanced treatment facility 73 and subjected to a purification treatment in which nutrients are removed.

As shown in FIG. 3, the acid fermentation tank 10 of the present invention includes a discharge pipe 15 and a return pipe 35, And the solubilization unit 50 is connected to the acid fermentation tank 10 through the banny line 16 and the refueling pipe 12.

As shown in FIG. 3, in the present invention, the acid fermentation tank 10 in which the wastewater to be treated initially flows is selectively floated in the form of supernatant water in which the organic wastewater is digested, drained, And the sludge is discharged through the bagney tube 16 at the lower end.

In the acid fermentation tank 10, a solubilization apparatus 50, which is a separate reaction tank for dissolving and decomposing the digested digested sludge by alkali decomposition and heating, is connected through a reintroduction pipe 12, and a methane fermentation tank The transfer pipe 35 branched from the discharge pipe 33 is provided in the discharge pipe 33 of the methane fermentation tank 30 and is connected to the inside of the acid fermentation tank 10, Some of the treated water is re-introduced into the acid fermentation tank 10.

The digestion process of the organic wastewater in the acid fermentation tank 10 proceeds so that the introduced organic wastewater flows naturally in the acid fermentation tank 10 while being extinguished so that the treated water and the digested sludge can be stably separated from each other Therefore, in the present invention, it is possible to isolate the organic wastewater initially introduced into the acid fermentation tank 10 and the flow path of the floating wastewater, and to ensure smooth and continuous treatment water flow and stable selection and withdrawal of the wastewater. The inlet corrugation 13 and the collecting portion 14 are formed in the fermentation tank 10.

That is, as shown in FIG. 4 showing the acid fermentation tank 10 of the apparatus of the present invention, an inlet correlation 13 is provided in the center of the inside of the acid fermentation tank 10 with the upper and lower ends opened and vertically standing, An inlet pipe 11 through which organic wastewater to be treated first flows and a reintroduction pipe 12 through which a solubilized digested sludge is connected are connected to the solubilization unit 50, And the outlet of the re-inlet pipe (12) are formed in the upper end of the inlet pipe (13) so that the inflow wastewater and the digested sludge are introduced into the inlet pipe (13).

The wastewater and the solubilized digested sludge once introduced into the inlet column 13 are subjected to digestion treatment and solid-liquid separation while descending along the inlet column 13, and thus, as shown in FIG. 3, ), A dense layer of digested sludge or a dense layer of digested sludge is formed in the space between the bottom surface of the acid fermentation tank 10 and the treated water in the space between the outer circumferential surface of the inlet correlation 13 and the inner circumferential surface of the acid fermentation tank 10, .

As shown in FIG. 4, the symbol number formed in the upper part of the acid fermentation tank 10 flows along the side end portion of the collection portion 14, which is a kind of upper open annular water channel formed on the inner peripheral surface of the acid fermentation tank 10, And then discharged to the outside of the acid fermentation tank 10 through the discharge pipe 15, and the discharged treated water is transferred to the methane fermentation tank 30.

The treated water introduced into the methane fermentation tank 30 through the discharge pipe 15 is subjected to methane fermentation treatment. The generated digested gas is discharged to the outside of the methane fermentation tank 30 and may be stored in the gas holder 72 or the like as shown in FIG. , The treated water in which the organic matter is decomposed is discharged to the outside of the methane fermentation tank 30 through the discharge pipe 33. As shown in FIG. 2, the discharged treated water passes through a separate advanced treatment facility 73, May be removed.

3, a part of the treated water branched and connected to the return pipe 35 is conveyed to the acid fermentation tank 10 in the methane fermentation tank 30, As shown in FIG. 4, a spraying device 17 in which a plurality of spray holes 18 are perforated as a ring-shaped tubular body is provided inside the acid fermentation tank 10, and the spray- By connecting the device 17, uniform and rapid diffusion of the treated water in the acid fermentation tank 10 is made possible.

That is, in performing the washing process of separating the dissolved substances in the extinguished sludge from the sludge by mixing the treated water conveyed in the methane fermentation tank 30 with the extinguished sludge in the acid fermentation tank 10, In the anaerobic digestion system, as shown in FIG. 1, the feed pipe 35 is simply connected to the lower portion of the acid fermentation tank 10, so that sufficient contact between the treated feed water and the digested sludge is not achieved, The water is raised along the wall surface of the fermentation tank 10 so that a sufficient elution effect can not be obtained. Accordingly, in the present invention, as shown in Fig. 4, the circulation pipe 35 connected to the return pipe 35, (17) composed of a plurality of fine spray holes (18) formed through a plurality of tubular walls of the annular body and a plurality of minute spray holes (18) The digested sludge and treated Trunk sufficient contact was to be in accordance with the.

The digested sludge settled in the lower part of the acid fermentation tank 10 is discharged through the vanny tube 16 and introduced into the solubilization unit 50.

The solubilization of the digested sludge destroys the cell walls of the microorganisms constituting the degradable digestive sludge discharged from the acid fermentation tank 10 to expose the intracellular organic matter. In the present invention, a method of heating and simultaneously supplying an acidic or alkaline treatment agent Thereby performing solubilization.

3, the solubilization apparatus 50, which is a kind of reaction tank for storing and treating the digested sludge, is connected to the acid fermentation tank 10, and an acidic or alkaline processing agent is added to the digested sludge stored in the solubilization apparatus 50 And a heating device 52 such as an electric heating line, a hot water tank, or a hot water pipe is provided so that the addition of an acidic or alkaline treatment agent for chemically decomposing the cell wall and the heating for promoting the decomposition action are performed in parallel Whereby the digesting sludge can be rapidly solubilized.

The digested sludge solubilized in the solubilization unit 50 is reintroduced into the acid fermentation tank 10 through the reintroduction pipe 12 and digested so that the amount of digested sludge generated in the acid fermentation tank 10 can be remarkably reduced have.

5 is a flowchart of a wastewater treatment method of the present invention for extinguishing organic wastewater using the apparatus of the present invention described above, which will be described in detail as follows.

As shown in FIG. 5, the wastewater treatment method of the present invention starts with a mixing step (S10) of mixing mixed wastewater by mixing sewage sludge and food wastewater.

In the mixing step (S10), the sewage sludge having a low organic matter content and the food wastewater which has a high organic matter content but high salinity are mixed, thereby increasing the organic matter content to a desired level and reducing the salinity, 2, a separate mixing tank 71 is formed before the acid fermentation tank 10 to form a mixed wastewater in which sewage sludge and food wastewater are mixed at a predetermined ratio, And can be carried out through various types of facilities such as a combined-type pipe as a simpler form.

The mixed wastewater generated in the mixing step S10 is transferred to the acid fermentation tank 10 and subjected to an acid fermentation step S21 in which a hydrolysis and an acid production reaction are carried out. In the acid fermentation step S21, The treated water is floated as a symbol water and the digested sludge is settled to the lower part of the acid fermentation tank 10.

After the acid fermentation step S21 is carried out, the waste water in the acid fermentation tank 10 is transferred to the methane fermentation tank 30 and the precipitated digested sludge in the acid fermentation tank 10 is transferred to the solubilization apparatus 50 And a methane fermentation step S23 for performing a methane generation reaction in the methane fermentation tank 30 and a part of the methane water in the methane fermentation tank 30 are returned to the acid fermentation tank 10, Is carried out to carry out a conveyance cleaning step S31.

In the solubilization apparatus 50, an acidic or alkaline treatment agent is added to the stored digested sludge, and at the same time, the digested sludge is heated to solubilize the degradable digestible sludge. The digested sludge, which has been solubilized, is re- The reprocessing step S41 is performed, whereby the waste water treatment method of the present invention is completed.

10: acid fermentation tank
11: Inflow pipe
12: Re-entry
13: Correlation
14: Housekeeper
15: discharge pipe
16:
17: Sputtering device
18: Spout ball
30: methane fermentation tank
33: Discharge tube
35: Return pipe
50: Solubilizing device
51: treatment agent inlet
52: Heating device
71: mixing tank
72: Gas holder
73: Advanced Treatment Facilities
S10: Mixing step
S21: acid fermentation step
S22:
S23: methane fermentation step
S31: Transfer cleaning step
S41: Reprocessing step

Claims (3)

An anaerobic digestion apparatus for digesting organic wastewater, comprising: an acid fermentation tank (10) in which hydrolysis and an acid production reaction of wastewater are carried out; and a methane fermentation tank (30) in which a methane formation reaction of the treated water discharged from the acid fermentation tank And a part of the treated water discharged from the methane fermentation tank 30 is transferred to the acid fermentation tank 10 to clean the dissolved substances in the digested sludge in the acid fermentation tank 10 As a result,
The acid fermentation tank 10 is provided with a vanny tube 16 for discharging the precipitated digested sludge and a solubilization device 50 for solubilizing the digested sludge discharged from the acid fermentation tank 10, Lt; / RTI >
Characterized in that a solubilizing device (50) in which digested sludge is stored is provided with a heating device (52) for heating the digested sludge which is provided with a treating agent inlet (51) for injecting the treating agent into the digested sludge that is stored, Two - phase anaerobic digestion system.
The acid fermenter (10) according to claim 1, wherein the acid fermenter (10) is provided with an inlet port (13) at the center thereof and connected to the inlet pipe (11) and the solubilization apparatus (50) The wastewater discharged from the inflow pipe 11 and the re-inflow pipe 12 and the extinguished sludge are introduced into the inlet pipe 13, while the re-inflow pipe 12 into which the solubilized extinguishing sludge flows is introduced.
A transfer tube 35 is connected to the lower part of the acid fermentation tank 10 to transport the treated water discharged from the methane fermentation tank 30 and a plurality of spray holes 18 are formed as an annular tube below the acid fermentation tank 10, The treated water discharged from the methane fermentation tank 30 is discharged through the spray hole 18 of the spraying device 17 and is discharged from the methane fermentation tank 30, And is sprayed into the fermentation tank (10). The sludge treatment type cleansing type two-phase anaerobic digestion device.
A method for treating wastewater using a sludge reprocessing type cleansing two-phase anaerobic digestion apparatus according to claim 1 or 2,
(S10) mixing the sewage sludge and the food wastewater to form mixed wastewater;
An acid fermentation step (S21) in which mixed wastewater is introduced into an acid fermentation tank (10) to perform a hydrolysis and acid production reaction;
A discharging step (S22) of transferring the water in the acid fermentation tank (10) to the methane fermentation tank (30) and transferring the precipitated digested sludge in the acid fermentation tank (10) to the solubilization apparatus (50);
A methane fermentation step (S23) of performing a methanogenic reaction in the methane fermentation tank (30);
A conveyance cleaning step (S31) of conveying a part of the symbol water in the methane fermentation tank (30) to the fermentation tank (10) to clean and separate dissolved substances in the digested sludge;
And a reprocessing step (S41) of re-introducing the digested sludge solubilized in the solubilization apparatus (50) into the acid fermentation tank (10) and digesting the digested sludge. Wastewater treatment method

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