KR100419827B1 - Biological, pysical and chemical treatment method of waste water from livestock - Google Patents

Abstract

The present invention relates to a biological, physical and chemical treatment method of livestock wastewater, more specifically, the raw water storage tank 10 for the first livestock wastewater to stay; Anaerobic tank 20 to induce intracellular phosphorus release, Nitrogen denitrification tank 30 and 50, Nitrogen oxides produced in aerobic tank 1 (40) and in aerobic tank 1 in which nitric oxide is produced and phosphorus intake by microorganisms occurs Internal return water transfer line 100 to return to denitrification tank 1 (30), right member water supply line 120 to supply organic matter contained in raw water to denitrification tank 2 (50) for supply of insufficient carbon source, denitrification tank 2 Aeration tank 2 (60) used to remove the remaining carbon source residues, a settling tank 70 in which the introduced microorganisms are settled, and a return sludge transfer to return the microorganisms of the settling tank to the anaerobic tank 20 and the denitrification tank 2 (50). A bioprocess comprising lines 110a and 110b; A physical process of removing the suspended solids introduced through the right member water supply line by the deposition membrane separation tank 80 after passing through the settling tank 70; And it is made of a chemical process for the removal and sterilization of suspended solids, ammonia nitrogen and dissolved phosphorus by the electrolysis tank 90 to improve the removal rate of nitrogen and phosphorus and to provide an economical livestock wastewater treatment method.

Description

Livestock Wastewater Treatment Method {BIOLOGICAL, PYSICAL AND CHEMICAL TREATMENT METHOD OF WASTE WATER FROM LIVESTOCK}

The present invention relates to a biological, physical and chemical treatment method of livestock wastewater, and in particular, to improve the total nitrogen and phosphorus removal efficiency by performing a continuous two-stage installation of denitrification tank and supply of right member water in a biological treatment process.

Today is an age of environment. Therefore, awareness of environmental preservation is spreading, and among them, social needs for water quality improvement and preservation for the water resources of rivers and streams used as water resources are increasing. The pollution caused by livestock wastewater is serious among the pollutants that deteriorate the water quality of these water sources, and the legal system for this is becoming strict.

Livestock wastewater is the sewage from livestock farms, and most of the livestock manure and washhouse water are used. These are not only large amounts of organic material loads (BOD) and solids loads (TSS) but also nitrogen (TN), which is toxic to humans when entering the water supply area. And it contains a lot of phosphorus (TP) and the color that causes a visual aversion is quite high. Among them, nitrogen exists in the state of organic nitrogen (ammonia / ammonium) such as urea and amino acids in water, and phosphorus is organic phosphorus (phosphate) such as protein, ATP, etc. Since these pollutants are introduced into the water supply as they are in the form of or in a state where they are not completely treated, eutrophication occurs in a closed water system such as a dam.

In order to treat livestock wastewater having such characteristics and problems, conventionally, the biological sludge has been somewhat successful in removing simple organic materials and solid materials by using activated sludge method or its modified methods, but the treatment efficiency of nitrogen and phosphorus is low. There was a problem of low economic feasibility due to excessive use of power. In addition, physical and chemical treatment methods such as pantone oxidation and electrocoagulation cause secondary pollution of the treated sludge and have high maintenance costs due to the use of expensive chemicals.

On the other hand, one of the methods of removing nutrients in the water biological treatment method uses microorganisms. At this time, in the aerobic state in which air is supplied, organic matter and oxygen are consumed and used as energy for growth, and then converted to carbon dioxide and water, phosphorus is taken into the body, and ammonia nitrogen is converted to nitrate nitrogen ( Nitrification). On the other hand, in an anoxic state where no air is supplied, nitrate nitrogen is converted to nitrogen gas (denitrification), and organic processes are consumed in this process. At this time, the generated nitrogen gas is discharged from the water to the atmosphere and removed. In this process, since denitrification requires the separate supply of organic materials used as a carbon source from outside, the burden on the cost is high, and therefore, the development of economic external carbon sources must be urgent, and a livestock wastewater treatment method must be accompanied for proper operation.

Therefore, in order to solve the above problems, the present invention is to install a biological treatment in two consecutive stages to improve the removal efficiency of nitrogen, while maximizing the operation of the treatment process in which the supply of the external carbon source necessary for denitrification is made in itself. The purpose is to provide a biological treatment process that allows the carbon source to be bypassed with organic matter contained in raw water and to supply sludge microorganisms from the sedimentation tank to the denitrification tank and the anaerobic tank through the internal conveying line for economic and efficient purification of livestock wastewater. There is this.

In addition, in order to remove suspended solids and untreated ammonia nitrogen, dissolved phosphorus and color in the raw water introduced for the supply of the carbon source, the biological wastewater from livestock wastewater, which is installed at the end of the biological treatment process, has a deposition membrane separation tank and an electrolysis tank. Its purpose is to provide physical and chemical treatment methods.

1 is a processing system diagram showing the procedure of the livestock wastewater treatment method of the present invention,

2 is a layout view of each step of treating livestock wastewater according to the method of the present invention.

<Description of the symbols for the main parts of the drawings>

10: raw water storage tank 20: anaerobic tank

30: denitrification tank 1 40: aerobic tank 1

50: denitrification tank 2 60: aerobic tank 2

70: sedimentation tank 80: immersion membrane separation tank

80: electrolysis tank

100: Internal return water transfer line

110a: conveying sludge conveying line (sedimentation tank → anaerobic tank)

110b: conveying sludge conveying line (sedimentation tank → denitrification tank 2)

120: right member supply line 130: biological treatment process

In order to achieve the above object, in the present invention, a biological treatment process comprising at least one return sludge line for returning the sludge of the raw water storage tank, at least one anaerobic tank, at least one aerobic tank, sedimentation tank and sedimentation tank to the anaerobic tank; A physical treatment process of treating biologically treated water using a membrane separation tank; In the livestock wastewater treatment method consisting of a chemical treatment process of the electrolytic treatment by sending the treated water undergoing a physical treatment process to the electrolysis tank, the biological treatment process, denitrification tank 1 (anaerobic tank)-aerobic tank to improve the nitrogen removal efficiency 1-denitrification tank 2 (anaerobic tank)-aerobic tank 2, the biological treatment leading to the 'denitrification tank-aerobic tank' is installed in two consecutive stages; the nitric oxide produced in the aerobic tank 1 through the internal transport water transfer line the denitrification And further denitrification by returning to tank 1; supplying raw water from the raw water storage tank to the denitrification tank 2 through the right member water supply line to supply the organic matter necessary for denitrification; organic matter residue and floating in the raw water remaining in the denitrification tank 2; Provided is a method for treating livestock wastewater, wherein the substance is decomposed in the aerobic tank 2.

In addition, the chemical treatment process by the electrolysis can increase the treatment effect by injecting a certain amount of sodium chloride.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 and 2 is a schematic diagram and layout showing the treatment procedure of the livestock wastewater of the present invention, the total nitrogen (TN) concentration in the raw water storage tank 10 to which the livestock wastewater first flows is about 3000 mg / l, the total phosphorus (TP) concentration Is a high load of about 500mg / ℓ, anaerobic tank 20 contributes to phosphorus removal in the biological treatment process of the previous stage of the present invention, induce intracellular phosphorus release to the phosphorus removal microorganisms and dissolved raw water introduced in aerobic tank 1 (40) After the microorganisms ingest the dissolved phosphorus released from the anaerobic tank 20, the microorganisms are removed in a method of removing the microorganisms from the settling tank 70.

Further, in order to improve the nitrogen removal efficiency, the denitrification tanks 30 and 50, which are biological treatment means, are installed in two stages in a row, and then passed through the electrolysis tank 90 using electrolysis as a post process. And discharged effluent with low phosphorus water quality, and also suspended solids (SS) in the wastewater are also subjected to a pretreatment biological process as a high load, and then subjected to the post-treatment of the deposition membrane separation tank (80) and the electrolysis tank (90). It is removed through physical and chemical processes.

In order to double nitrogen removal in the biological treatment process, the denitrification tank 1 (30) transfers the nitric oxide (NO _x -N) generated by nitrification in the aerobic tank 1 (40) to the internal transport pump 140 and the internal transport water transfer line (100). The nitrogen gas is degassed into the atmosphere by returning through N) and further denitrification. At this time, in order to compensate for the shortage of organic matter, which is a carbon source necessary for denitrification of the denitrification tank 2 (50), about 10% of raw water is supplied through the right member water supply pump 150 and the right member water supply line 120 in the raw water storage tank 10 (v). / v) is introduced into the denitrification tank 2 (50) to increase the denitrification effect by using the organic material contained in the raw water as a carbon source. The aerobic tank 2 (60) is used in the denitrification tank 2 (50) and is installed and used for the purpose of complete mixing of the microorganisms in order to remove residues and suspended substances of organic matter, which are carbon sources in the remaining right member water, and to secure microorganisms in the sedimentation basin.

The settling tank 70 precipitates the microorganisms introduced in the aerobic tank 2 (60) and transfers the microorganisms to the anaerobic tank 20 and the denitrification tank 2 (50) through the conveying sludge pump 160 and the conveying sludge conveying line (110a, 110b). do. The sludge transfer to the denitrification tank 2 (50) is to maintain a high concentration of denitrification microorganisms in the denitrification tank 2 (50) to obtain a higher denitrification rate than the shear denitrification tank 1 (30).

The bypass water supply through the right member water supply line 120 is supplied with a high concentration of nitrogen and suspended solids as well as a carbon source supply to the denitrification tank 2 (50). As a solution for this, after passing through the settling tank (70), the sedimentary membrane separation (80) and the electrolysis tank (90) are installed at the rear end.

The immersion membrane separation tank 80 solves the blockage phenomenon by installing a hollow fiber membrane at the top and an air supply line at the bottom to supply air. The deposition membrane is operated to remove suspended matter in the right member water supplied to the denitrification tank 2 (50).

Electrolysis tank 90 is installed for the purpose of floating material, ammonia nitrogen, dissolved, chromaticity removal and sterilization by installing a titanium electrode plate coated with iridium oxide (IrO ₂ ) on the anode. In addition, in the electrolysis tank, sodium chloride (NaCl) is injected into the metering pump in an amount of 50 l / d to increase the electrolyte concentration to increase the indirect oxidation effect, thereby reducing the power cost and removing the contamination.

Table 1 shows the results of the water quality of each process of the biological process, the physical process of immersion membrane separation, and the unit process of chemical process of electrolysis.

Water quality per unit process (mg / ℓ) TBOD TSS T-N NOx-N T-P Influent 31,000 16,500 3,000 - 500 Runoff Biological treatment process Expiry 1 25 64 930 880 14 Expiry 2 48 285 338 160 37 Deposition membrane separator 43 13 338 160 37 Electrolysis tank 34 7 209 138 18

As described above, the livestock wastewater treatment method of the present invention can effectively remove nitrogen (TN) and phosphorus (TP), which are pollutants of the water system, without being treated by conventional methods through biological, physical, and chemical treatment processes. In particular, it is possible to reduce the cost by repeating the denitrification process by biological treatment process and solving the supply of carbon source necessary for the removal of nitrogen through the right member water supply line, and circulating nitrates and microorganisms through the return line in the process. The nutrient removal ability and economical treatment method have been obtained.

Claims (2)

A biological treatment process comprising at least one return sludge line for returning raw water storage tank, at least one anaerobic tank, at least one aerobic tank, sedimentation tank and sludge of the sedimentation tank to the anaerobic tank; A physical treatment process of treating biologically treated water using a membrane separation tank; In the livestock wastewater treatment method consisting of a chemical treatment process of electrolytic treatment by sending the treated water that has undergone physical treatment process to the electrolysis tank, The biological treatment process, In order to improve the nitrogen removal efficiency, biological treatments leading to 'denitrification tank-aerobic tank' in order of denitrification tank 1 (anaerobic tank) -aerobic tank 1-denitrification tank 2 (anaerobic tank) -aerobic tank 2 are installed in two consecutive stages; Further denitrification by returning the nitric oxide produced in the aerobic tank 1 to the denitrification tank 1 through an internal transport water transfer line; Supplying raw water to the denitrification tank 2 from the raw water storage tank through the right member water supply line to supply the organic matter necessary for denitrification; Livestock wastewater treatment method characterized in that the remaining organic matter and suspended matter in the raw water used in the denitrification tank 2 is decomposed in the aerobic tank 2. The method of claim 1, The chemical treatment process by the electrolysis is a method of treating livestock wastewater, characterized in that to increase the treatment effect by injecting a certain amount of sodium chloride.