KR101745562B1 - Advanced treatment process for high-concentrated organic wastewater - Google Patents

Abstract

The present invention relates to an advanced treatment process for highly concentrated organic wastewater, and more particularly, to a process for treating organic wastewater with high efficiency by combining a pretreatment process with a protein skimmer and an electrochemical treatment in a biological treatment process, The present invention relates to an advanced treatment process for highly concentrated organic wastewater which can enhance water treatment efficiency and meet enhanced water quality standards by highly oxidizing treatment of refractory materials.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-concentration organic wastewater treatment apparatus,

The present invention relates to an advanced treatment process for highly concentrated organic wastewater, and more particularly, to a process for treating biological wastewater by biologically treating a high-concentration organic wastewater with a pretreatment device comprising a protein skimmer and an electrochemical treatment device, The present invention relates to an advanced treatment process for highly concentrated organic wastewater which can reduce the organic load of the process and maintain the oxygen activity at a high level to increase the water treatment efficiency to meet the enhanced water quality standard.

In general, organic wastewater such as livestock wastewater, food wastewater, and milk processed wastewater is very difficult to treat because it contains a large amount of organic matter, nutrients such as nitrogen and phosphorus, and is discharged into a river or a lake Causing eutrophication phenomenon.

In other words, various kinds of algae breed in rivers and lakes, and in the course of their breathing, they deplete dissolved oxygen in the water, which causes aquatic plants and animals to be killed, turbid water, and bad odor.

Furthermore, as the consumption of livestock products continues to increase due to industrial development and income increase, the amount of livestock wastewater discharged from livestock farms further increases, resulting in serious environmental pollution such as water quality and soil.

In addition, the livestock wastewater contains a large amount of biodegradable material, and since the water quality and the flow rate of the wastewater discharged are largely fluctuated due to the structure of the farmhouse installed in the livestock farmhouse, it is difficult to find a standardized treatment method and the conventional chemical coagulation and biological treatment There is a risk of exceeding the emission allowance criteria when processing by the process.

As a result, the government is implementing regulations to reduce the pollution of animal wastewater, such as management and support of livestock farmers, strengthening regulations on pollutant emissions, and expanding public treatment facilities. By strengthening legislation on livestock wastewater treatment, The water quality of the effluent is strictly regulated by further increasing the standards for the pollutants involved, namely, the biochemical oxygen demand (BOD) and suspended solids (SS) and in particular the total nitrogen (TN) and total phosphorus .

For this purpose, prior to biologically treating the degradation wastewater, a method of lowering the concentration of the organic matter by performing a pretreatment process with a chemical coagulant such as an aluminum salt has been proposed in the prior art, and the present invention continues the effect of this pretreatment process, And a new method for efficiently treating the high concentration organic substances and nutrients contained in the water.

Korean Patent No. 795072 entitled "Method and apparatus for treatment of high concentration wastewater containing livestock manure" (2008.01.09) Korean Utility Model Registration No. 470808 entitled "Organic agriculture and wastewater treatment system" (2014.01.03) "High concentration organic wastewater treatment device" of Korea Patent No. 1222704 (2013.01.09) Korean Patent No. 1241289 entitled " Apparatus and Method for Treating High-Concentration Organic Wastewater and Nitrogen and Phosphorus (2013.03.04) " Korea patent registration 1009457220000 "Advanced treatment of high concentration wastewater such as livestock manure and manure, recycling method of resources and processing device for it" (2010.02.26) Korean Patent No. 970576 entitled "Apparatus for removing organic matter, nitrogen and phosphorus from livestock wastewater and method for treating livestock wastewater using the same" (2010.07.09) Korean Patent No. 784933 entitled "Organic matter and Nitrogen Treatment System of Highly Organic Wastewater" (2007.12.05)

The present invention has been made to solve the above problems, and it is an object of the present invention to efficiently treat nitrogen and phosphorus and decomposable organic substances contained in high concentration organic wastewater through a pretreatment process by microbubbles and electrolysis as a pretreatment process of biological treatment And to provide a highly advanced organic wastewater treatment process.

According to an aspect of the present invention, there is provided a process for advanced treatment of highly concentrated organic wastewater comprising: (a) a first pre-treatment step of adsorbing and removing organic substances in organic wastewater using micro bubbles; (B) a secondary pretreatment step of converting the first pre-treated wastewater into a biologically degradable material by pretreating a high concentration organic component by an electrode reaction; A biological treatment step of decomposing the organic matter using the biofilm carrier of the second pretreated wastewater; And a membrane filtration step of filtering the biologically treated wastewater with a membrane and oxidizing the membrane using microbubble ozone.

Herein, the step (a) is characterized in that the protein skimmer is used, and the two steps are connected and pretreated.

In the step (b), an electrode electrolytic cell filled with a plurality of electrically conductive particles between three cylindrical anode electrodes and two cylindrical anode electrodes is used.

In addition, the step (a) is characterized in that water treatment is performed with five aerobic basins, a settling tank, an anaerobic tank and an anoxic tank to decompose the pretreated wastewater by microorganisms.

As described above, according to the present invention, in the process of treating the high concentration organic wastewater such as livestock wastewater, a first pre-treatment using a two-stage high-level oxidation system by a protein skimmer and a bio- It is possible to efficiently treat the organic and high-concentration non-degradable wastewater including nitrogen and phosphorus, thereby providing an appropriate advanced treatment process for satisfying the water quality standard for effluent water.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically shows a process for the overall treatment of highly concentrated organic wastewater according to the present invention; FIG.
2 is a view schematically showing a primary pretreatment apparatus of the present invention
Figure 3 schematically illustrates the membrane filtration process of the present invention
Figure 4 is a photograph of the high concentration organic wastewater pretreated by the primary and secondary pretreatment processes of the present invention

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings so that those skilled in the art can readily implement the technical idea of the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

FIG. 1 is a view schematically showing a general advanced treatment process of a high concentration organic wastewater according to the present invention, FIG. 2 is a view schematically showing a first pre-treatment apparatus (altitude oxidation system) of the present invention, FIG. 4 is a photograph of a high concentration organic wastewater pretreated by the primary and secondary pretreatment processes of the present invention. FIG.

The present invention provides a process for treating a high concentration organic wastewater, comprising: a first pre-treatment step using fine bubbles; A second pre-treatment step through electrolysis; Biological degradation step using biofilm carrier; As shown in FIG. 1, the high-concentration organic wastewater is converted into a biologically decomposable material through a micro-bubble pretreatment and an electrochemical pretreatment process to remove contaminants which can not be biologically decomposed, After the treatment, the solid byproducts generated from the anaerobic tank 1, the anaerobic tank 3 and the anaerobic tank 4 were transferred to a decanter, and the filtrate was passed through an anaerobic tank, anoxic tank, And removing the colloidal solids component from the filtration tank.

This will be described in detail as follows.

[1] Primary pretreatment

In this process, a protein skimmer is added to the organic wastewater in order to highly oxidize the poorly decomposable organic substances in the organic wastewater. Is used.

The protein skimmer 100 absorbs and removes organic substances (polymeric organic substances) in the water together with bubbles by mixing organic wastewater and fine air bubbles. The protein skimmer 100 has a tubular shape with an inlet port and an outlet port, (3) for circulating wastewater inside the main body (1), a fine bubble supplying section (2) for supplying fine bubbles to the inside of the main body, a collecting section ).

That is, the organic wastewater flows into the main body 1 through the inlet, fine nano-sized air bubbles are supplied into the main body where the wastewater is stored by the fine bubble supplying part 2, and the wastewater is smoothly In the circulation process, the surface tension of the air bubbles causes the organic material in the water to become entangled with the surface of the air bubbles and mix well. As a result of this skimmer operation, the fine bubbles become a large amount of bubbles, And is removed by the collecting part 4 after it has floated on the water surface.

At this time, if the size of the minute bubbles in the main body 1 is reduced or the time for staying the minute bubbles is adjusted long, the water treatment efficiency by the skimmer can be further increased.

As shown in FIG. 2, the protein skimmers are connected in two stages. In the first skimmer, the wastewater from which the organic material is removed flows into the second skimmer, and the organic material is removed by the same method.

The first pretreatment step using the protein skimmer utilizes the principle of separating and separating particulate matter or dissolved organic substances present in the high concentration organic wastewater into bubbles rising in water. In this process, And organic matter such as protein and nitrogen is adsorbed to the outside of the body, and oxygen is supplied while decreasing the load in the biological treatment process in the post-process, thereby increasing the dissolved oxygen.

[2] Second pre-treatment

In the first pre-treatment step, the wastewater pretreated with a protein skimmer is converted into a decomposable state in a component which can not be biologically treated in a post-process by using an electrochemical oxidation reaction. In this process, The electrode electrolytic bath 200 is used.

That is, although not shown in the drawing, the electrode electrolytic cell is constituted by arranging three cylindrical anode electrodes and two cylindrical cathode electrodes in a cylindrical reaction tank and filling a plurality of electrically conductive particles between the electrodes.

At this time, the electroconductive particles function as a particulate electrode, so that a plurality of fine electrolytic cells are formed as a whole, thereby increasing the effective electrode area and shortening the moving distance of the substance to be treated in the organic wastewater in the electrolytic cell Therefore, the reaction rate can be shortened.

In addition, since the bivalent iron ions that are finely dissolved in the anode remove the total phosphorus component in the wastewater, and the electrode reaction causes the high concentration organic component to be pretreated and converted into a biologically degradable substance, Processing is possible.

[3] Biological treatment

The water treatment tank used in the present process is a reaction tank composed of a settling tank, an anoxic tank, an anaerobic tank, and five aerobic tank, Each of the reaction vessels is charged with 30% of the biofilm carrier, and the biofilm is formed by adhering the microorganisms that can survive under the extreme conditions to enhance the treatment efficiency of the additional pollutants.

First, the pretreated wastewater flows into the aerobic reactor and converts organic nitrogen and ammonia nitrogen into nitrate nitrogen by biological decomposition as well as removal of organic matter (BOD). At this time, the organic wastewater flowing into the aerobic tank is at a high concentration, and the aerobic tank is composed of the first aerobic tank 311, the second aerobic tank 312 and the third aerobic tank 313 to remove organic matter.

The aerated wastewater flows into the sedimentation tank 320 and is subjected to solid-liquid separation with the dehydrated filtrate and solid particles. The dehydrated filtrate is transferred to the anaerobic tank 330 and the solid particles are transferred to the decanter 321.

That is, in the case of the high concentration organic wastewater, 70% or more of the organic wastewater is generated as solids particles as the pollutants are reduced. Therefore, it is necessary to remove them from the titration process. For this, the solids particles generated in the biological treatment process are removed from the decanter 321, And the dehydrated filtrate resulting therefrom is transferred to a primary pretreatment tank (skimmer: 100) for further treatment, and the solids recovered by the tester are recycled as compost or organic fertilizer.

The wastewater (dehydrated filtrate) flowing out of the settling tank 320 removes phosphorus from the anaerobic tank 330 and the nitrate nitrogen is removed from the anaerobic treated wastewater by denitrification using an organic carbon source in the anoxic tank 340.

The anaerobic treated wastewater is nitrified by nitrifying microorganisms and removed by excessive intake of microorganisms in the No.

[4] membrane filtration

And filtering the biologically treated wastewater with a membrane filtration apparatus to finally treat the wastewater. The fine wastewater is removed through a separation membrane to remove fine colloidal substances.

3, the membrane filtration apparatus is provided with an ozone supply unit 411 for supplying ozone through fine bubbles to oxidize and disinfect fine organic substances, and is capable of disinfecting the filtered water Is discharged through the treatment tank 500.

At this time, air is poured into the membrane to remove the debris from the wastewater adhered to the membrane 420, and the debris is separated by air cleaning to be sent to the membrane filtration tank 410, Sodium hypochlorite (NaOCl) is supplied to treat microorganisms and the like on the surface of the membrane 420.

The material that can not be biologically degraded as described above is converted into a decomposable material through pretreatment and biologically treated to be water-soluble, thereby satisfying water quality standards for effluent water.

For example, the present invention can maintain a dissolved oxygen concentration of 8 ppm or more, and also solve the problem of odor generated in a high concentration organic wastewater treatment facility, compared to the case where the concentration of dissolved oxygen in processes using conventional micro-bubbles is 1.5 ppm. So that the microbial reaction in the biological reaction tank can be promoted.

In addition, unlike other water treatment processes, it is possible to remove about 50% of nutrients including nitrogen phosphorus without using chemical coagulant, and has excellent removal efficiency of fatty compounds, proteins and oil components.

Particularly, since it is treated through a bioreactor after a two-stage pretreatment and an electrochemical pretreatment process, the residence time can be drastically reduced compared to conventional processes even at a high concentration of 50,000 mg / L or more of organic matter, It is a good way to solve the site problem.

1: Main body 2: fine bubble supplying part
3: Pump 4:
100: Protein skimmer 200: Electrolysis tank (electrolysis device)
311: First crew 312: Second crew
313: the third crew 314: the fourth crew
315: 5th aeration tank 320: settling tank
321: decanter 330: anaerobic tank
340: Anoxic tank 410: membrane filtration tank
420: Membrane 500: Treatment tank

Claims (4)

(A) a first pre-treatment step of adsorbing and removing organic substances in organic wastewater using micro-bubbles;
(B) a secondary pretreatment step of converting the first pre-treated wastewater into a biologically degradable material by pretreating a high concentration organic component by an electrode reaction;
(2) The second pre-treated wastewater is decomposed by using a biofilm carrier, and the solid particles generated therefrom are dehydrated by using a decanter, and the dehydrated filtrate resulting therefrom is transferred to the first pre-treatment step A biological treatment step And
A membrane filtration step of filtering the biologically treated wastewater with a separation membrane and oxidizing the wastewater using microbubble ozone,
In the step (b), the electroconductive particles act as a particulate electrode by using an electrode electrolytic cell filled with a plurality of electroconductive particles between three cylindrical anode electrodes and two cylindrical cathode electrodes. Advanced processing process. The method according to claim 1,
The process of (a) above is characterized in that a protein skimmer is used, and the two stages are connected and pretreated. delete The method according to claim 1,
Wherein said step (a) comprises the steps of: (a) treating said wastewater with water by treating said wastewater with 5 aerators, a settling tank, an anaerobic tank and an anoxic tank to decompose the pretreated wastewater by microorganisms;

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