KR100673841B1 - High concentration organic wastewater treatment method use of ceramic coagulant - Google Patents

Abstract

The present invention provides a method for effectively solid-liquid separation of high concentration organic SS-containing wastewater containing livestock wastewater and food waste desorbing liquid using a ceramic flocculant, and then the wastewater from which SS is removed is compacted using membrane treatment, biological anaerobic and aerobic treatment. And to suggest an economical treatment method.

The present invention is to coagulate sedimentation of the high concentration organic SS-containing wastewater introduced to achieve the above object by using a ceramic flocculant, and the liquid separation liquid separated by precipitation is treated with primary and secondary membranes, and the solid cake is subjected to consignment treatment and Compost and remove the small amount of high-density primary membrane concentrated water from which the permeate is removed from the primary membrane for a long time biological anaerobic treatment and aerobic treatment, and return it to the initial flocculation tank, and the secondary membrane concentrated water from the secondary membrane is separated by sedimentation. It is returned to be reprocessed together with the liquid separation liquid.

The treatment method of high concentration organic SS-containing wastewater using the ceramic coagulant of the present invention can be applied and applied as the most suitable treatment method for the high concentration SS and BOD, COD-containing wastewater generation sites that have been difficult to treat.

Ceramic flocculant, flocculation sedimentation, high concentration wastewater, SS

Description

High concentration organic wastewater treatment method use of ceramic coagulant

1 is a block diagram showing a schematic configuration of the present invention.

2 is a block diagram showing a preferred embodiment of the present invention.

<Description and Name of Each Part>

1 Inflow of high concentration organic SS containing wastewater

2 water inflow

3 ceramic flocculant inflow

4 Consignment or composting of solid cakes

5 Aeration tank inflow of liquid separation liquid

6 Reservoir inflow of primary membrane permeate

7 Biological anaerobic inflow of primary membrane concentrate

8 Biological aerobic inflow of biological anaerobic treated water

9 Return the biological aerobic tank treated water to the first flocculation reactor

11 Discharge of Secondary Membrane Permeate

12 Return the secondary membrane concentrated water to the aeration tank

13 Wastewater Transfer Pump

14 Feed Pump

15 Primary High Pressure Pump

16 Secondary High Pressure Pump

10 Drug Storage Tank

20 flocculation reactor

30 decanta

40 aeration tanks

50 Precision Filtration Device

60 primary membrane

70 reservoir

80 secondary separator

90 biological anaerobic tank

100 biological aerobic tanks

The removal of SS from high concentration SS containing wastewater, including livestock waste and food waste stripping liquor, is one of the most important concerns in determining overall treatment efficiency.

Precipitant separation when conventional flocculants such as alumina, ferrous chloride, and ferric chloride are applied to high-concentration organic SS-containing wastewater with poor sedimentation and viscous SS substances, such as livestock wastewater and food waste desorbents, suspended in high concentration slurry. The efficiency is so small that it is difficult to see the expected effect. In some cases, an excessive amount of the coagulant input may be added in an excessive amount, but this may cause an economic decrease by an excessive input of the coagulant, and it may be difficult to produce a satisfactory effect because it requires a difficult operating condition such as pH correction. In particular, pH correction is required for the use of flocculants, which leads to additional consumption of alkaline agents.

Wastewater that has not been completely SS removed is unlikely to produce satisfactory treatment efficiency at any stage of the process and results in an increase in the size of the entire treatment system, impeding economic system configuration.

In addition, wastewater containing high concentrations of organic SS often has tens of thousands of BOD and COD values even if the SS is removed, and biological anaerobic treatment, which is a representative method of treating high concentrations of BOD and COD, requires long residence times and large sites due to slow reaction. However, in Korea, due to the restriction on the site, it is not a realistic treatment method.

On the other hand, in the case of separation treatment using the separation membrane can be expected to be a good water quality and stable water quality has been applied to a lot of heavy water and sewage treatment. However, in the case of applying the membrane to the high concentration wastewater, the problem of treatment of concentrated water concentrated at high concentration and frequent fouling by SS act as a limit of application.

The present invention provides a method for effectively solid-liquid separation of a high concentration of organic SS-containing wastewater, which is poor in sedimentation property and cannot be treated compactly, using a porous ceramic flocculant having adsorptive properties such as ash, diatomaceous earth, loess, and activated clay, and then SS is removed. The present invention aims to provide a method for economically and compactly treating high concentration SS-containing wastewater through membrane treatment and biological treatment.

In more detail, the present invention aims to provide the most effective and simple method of flocculation and precipitation using porous ceramic flocculant, which is inexpensive and easy to use.

In addition, in the treatment of high concentration wastewater from which the SS is removed, the membrane treatment and biological treatment are effectively arranged to reduce the burden on the site caused by the biological treatment and to provide a method for completely treating the concentrated water generated during the membrane treatment.

In order to achieve the above object, the present invention provides a chemical storage tank (10) for storing a ceramic coagulant, a coagulation reaction tank (20) in which a high concentration of SS-containing wastewater and a ceramic coagulant react, and a transfer pump (13) for transporting the reacted slurry type wastewater. , The decanter 30 for solid-liquid separation of the condensed wastewater by a centrifugal force, the aeration tank 40 for aeration of the liquid separation liquid 5 separated from the decanter 30, and the wastewater of the aeration tank 40 with a precision filtration device 50 ) To feed the feed pump (14), the fine filtration device (50) for removing the fine SS of the wastewater and protecting the rear separator, and pressurized the wastewater from which the fine SS has been removed to the primary membrane (60). Primary high pressure pump (15), primary membrane (60) for reducing COD and BOD of wastewater, reservoir (70) for storing permeate (6) permeated from primary membrane (60), impermeable 1 Biology for Biological Treatment for BOD and COD Reduction of Primary Membrane Concentrates (7) Secondary high pressure pump 16 for pressurizing and transporting wastewater from the storage tank 70 in which the anaerobic tank 90, the aerobic tank 100, and the permeate 6 of the primary separation membrane 60 are stored to the secondary separation membrane 80. ), The secondary membrane (80) for treating the water quality of the wastewater to the effluent level.

Looking at the above configuration in detail, when the wastewater containing high concentration of SS is introduced (1) to the aggregation reaction tank 20 and reaches a high level, the ceramic flocculant of the chemical storage tank 10 is metered and stirred together. The high concentration of SS contained in the waste water is adsorbed by the ceramic coagulant having a porosity without special pH correction in the flocculation tank 20 to form floc.

At this time, the ceramic coagulant used has the adsorptive property due to the porous structure and serves to agglomerate and precipitate SS in the wastewater as fine particles having a particle size of about 10 to 100 micron. Typically, ash, diatomaceous earth, loess, and acid clay are used. Etc.

In addition, the chemical storage tank 10 serves to supply a predetermined amount when the water level reaches the high level due to the inflow of the waste water of the flocculation reaction tank 20 while storing and making a liquid state easy to inject by mixing the ceramic flocculant and water. In addition, the liquid state in which the ceramic coagulant and the water are mixed not only facilitates the injection but also increases the reaction efficiency with the SS in the waste water.

In addition, high concentration SS-containing wastewater often shows a high viscosity, which contributes to the improvement of the flocculation and sedimentation efficiency by assisting the adsorption and aggregation between the porous ceramic coagulant and the SS. High concentration SS-containing wastewater with floc is much reduced in viscosity and the decrease in viscosity improves floc sedimentation efficiency.

Wastewater in which floc is formed by reacting with a ceramic flocculant is gravity-precipitated and is transferred to decanta 30 to undergo a solid-liquid separation process. Decanta 30 can create a centrifugal force of thousands of times the gravity to obtain a maximum precipitation efficiency in a short time.

The solid waste separated from the decanta 30 requires separate treatment such as consignment treatment or composting (4), and the liquid separation solution (5) is aerated and transferred to the aeration tank (40). Adjust the pH to weak alkali in 40). Wastewater that has been aerated for some time in the aeration tank 40 may remove some of the COD and BOD in the wastewater.

The waste water aerated in the aeration tank 40 is transferred to the precision filtration device 50 to remove fine SS material and increase the efficiency of the membrane treatment process. Since most SS is already removed by the coagulation sedimentation by the ceramic coagulant, the SS load imposed on the microfiltration unit 50 is not large and can be operated without changing the filter for a long time. Precision filtration device 50 is applied to have a filtration precision of 1 ~ 10 micron.

Wastewater from which the fine SS is removed is treated with the primary separator 60 and the secondary separator 80 to remove BOD and COD to the effluent level, and the treated water is discharged 11.

The primary high pressure pump 15 and the secondary high pressure pump 16 pressurize the wastewater and supply it to each separator for optimum performance of the membrane treatment.

As the primary separator 60, an ultrafiltration separator having a biological anaerobic tank 90 and an aerobic tank 100 is applied. The permeated water 6 through which the wastewater introduced into the primary separation membrane 60 passes through the separation membrane is transferred to the reservoir 70 for treatment of the secondary separation membrane 80 and is not concentrated, and is concentrated, showing high BOD and COD. (7) is transferred to the biological anaerobic tank (90) to reduce the BOD and COD. Sufficient time anaerobic concentrated water is transferred to the biological aerobic tank 100 to ensure more stable water quality in the biological aerobic tank 100. Since the concentrated water 7 generated in the primary separation membrane 60 is smaller than the total wastewater, biological treatment time may be sufficiently provided even with a small site.

The treated water (9), which has passed through the biological anaerobic tank (90) and the aerobic tank (100), is transferred to the coagulation reaction tank (20) together with the inflow of the high concentration SS-containing wastewater (1) to dilute the high concentration SS-containing wastewater and improve the coagulation efficiency. Reprocessed through the system. The excess sludge generated in the biological treatment tank is returned to the coagulation reaction tank 20 together with the return of the treated water, and is separated into coagulation sedimentation with the raw waste water and treated as a solid cake.

On the other hand, the permeated water 6 passing through the primary separation membrane 60 is stored in the storage tank 70, the SS is insignificant and the COD and BOD is transferred to the secondary separation membrane 80 with much reduced state. The secondary separation membrane 80 is discharged by obtaining the final quality of the discharged water level using a single ultrafiltration membrane. Secondary membrane concentrated water 12 that did not pass through the secondary membrane 80 is returned to the aeration tank 40 at the front end of the microfiltration unit 50 and the liquid separation solution 5 separated by the decanter 30 and Reprocessed together.

As an embodiment of the present invention, the food waste stripping liquid generated in the food composting plant was treated. The pH of the desorption liquid is about 4, and it is a high concentration waste solution of SS 150,000 ~ 200,000ppm, BOD 100,000 ~ 120,000ppm, and COD 150,000 ~ 170,000ppm. 3 w / V% of the ash was applied as a ceramic flocculant to the food desorption solution and the pH was agglomerated without adjustment. The flocculant reacted with the ceramic coagulant formed fine floc and separated from the decanta (30), showing that the SS of the supernatant showed 2,000 ~ 3,000ppm, BOD 50,000ppm, and COD 70,000ppm. The solid cake separated from the decanter (30) was composted and the liquid separation liquid was aerated for 7 days with adjusting the pH to weak alkali in the aeration tank (40) to see the effect of removing BOD and COD. COD 50,000 ppm level. After the aeration, the water quality of the permeated water that passed through the microfiltration unit 50 and the primary membrane 60 of MWCO 200,000 was about 300-400 ppm BOD, 1,000 ppm COD, and 1 ppm or less. At this time, the concentrated water that did not pass through the primary separation membrane 60 was treated in an anaerobic tank for 25 days and in an aerobic tank for 15 days and returned to the coagulation reaction tank 20. The average water quality of the treated water that passed through the primary membrane 60 to the secondary membrane 80 of MWCO 10,000 was less than 50 ppm BOD, 50 ppm COD, and 1 ppm SS. It was conveyed to the aeration tank 40 in front of the microfiltration device 50 and reprocessed with the decanter 30 liquid separation liquid.

In another embodiment of the present invention, the livestock slurry wastewater was treated.

The pH of the livestock wastewater is neutral 7 and is a high concentration wastewater of SS 50,000ppm, BOD 30,000 ~ 50,000ppm, COD 150,000ppm, T-N 2,500ppm. 3w / V% of ash was applied to the livestock wastewater as a ceramic flocculant. As a result of separating the coagulated livestock wastewater from the decanter (30), the SS of the supernatant water was 1,000 ppm or less, BOD 10,000 ppm, COD 50,000 ppm, T-N 1,200 ppm and showed excellent treatment results. The solid cake separated from the decanter (30) was composted, and the liquid separation liquid was aerated for 7 days with pH adjustment with weak alkali in the aeration tank (40) for water quality of BOD 5,000ppm, COD 30,000ppm, TN 800 ~ 1,000ppm Got. The water quality of the permeated water that passed through the microfiltration unit 50 and the primary membrane 60 of MWCO 100,000 after aeration was about 500 ppm of BOD, 500 ppm of COD, and less than 1 ppm of SS and about 200 ppm of TN. The concentrated water that did not pass) was treated in an anaerobic tank for 25 days and in an aerobic tank for 15 days and then returned to the flocculation reactor (20). The average water quality of the treated water that passed the first separator 60 through the second separator 80 of MWCO 10,000 is BOD 30-50 ppm, COD 30-50 ppm, SS 1 ppm or less, and TN 20 ppm or less. The concentrated water that was not passed through was transferred to the aeration tank 40 in front of the precision filtration device 50 and retreated with the decanter 30 liquid separation liquid.

The present invention provides a method for effectively solid-liquid separation of high concentration organic SS-containing wastewater having poor sedimentation by using a ceramic flocculant, and then, a compact and economical treatment method using a membrane treatment, biological anaerobic, and aerobic treatment for the SS-removed wastewater. To present.

So far, high concentration organic SS-containing wastewater including livestock wastewater and food waste stripping liquid has been heavily dependent on the disposal method by ocean dumping, but it is urgent to obtain economic and effective treatment methods by strengthening the dumping conditions. In addition, in the case of a waste treatment plant equipped with a composting facility, there is no clear solution for the treatment of high concentration organic SS-containing wastewater generated after the separation of large solid materials.

The coagulation sedimentation method using the ceramic coagulant according to the present invention provides an effective treatment method for the difficulties of solid-liquid separation encountered in high-concentration organic SS-containing wastewater generation sites, such as livestock wastewater, food waste stripping liquid, and food wastewater. In addition, the membrane treatment, biological anaerobic and aerobic treatment is most appropriately arranged to provide a compact and economical treatment method that greatly reduces the site and solves the small amount of concentrated water generated in the membrane. The treatment method of the high concentration organic SS-containing wastewater using the ceramic flocculant of the present invention can be applied and applied as the most suitable treatment method for the high concentration SS and BOD, COD-containing wastewater generation sites that suffer from conventional treatment difficulties.

Claims (5)

In the treatment of high concentration organic SS-containing wastewater containing livestock wastewater and food desorption liquid, the high concentration organic SS-containing wastewater and ceramic flocculant are coagulated and precipitated, and the solid cake separated by sedimentation is composted or consigned. In the aeration tank, the organic matter is reduced by pH adjustment and aeration, and microfiltration is performed to remove fine SS from the wastewater treated in the aeration tank, and the permeated water that has passed through the primary membrane by separating the microfiltered wastewater into the primary membrane is 2 The primary membrane concentrate, which was separated by the secondary membrane and failed to pass through the primary membrane, was returned to the first flocculation tank after biological anaerobic treatment and aerobic treatment, and the secondary permeate passed through the secondary membrane was discharged and passed through. Wastewater treatment method containing a high concentration of SS, characterized in that the secondary membrane concentrated water not returned to the aeration tank delete delete delete delete

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