KR20030083651A - apparatus for recycling of machining wastewater by multi-stage filtering including membranes - Google Patents

Abstract

PURPOSE: Provided is an apparatus for recycling wastewater produced from machining process by multi-step filtering processes including membranes. CONSTITUTION: The apparatus comprises a raw water tank(1), an oil/water separation basin(2) for separating floated oils from the raw water, a pre-coat filter(3) for removing metal chips, non-metal impurities, suspended solids, and other oils, a cartridge type micro-filter(4) for removing contaminants which passes the pre-coat filter and are greater than 5 μm, a first storage tank(5) for filtrate of the micro-filter(4), an ultrafiltration membrane(5) for removing organic material with high molecular weight, color inducing material and N-H from the filtrate stored in the first storage tank(5), a second storage tank(6) for storing filtrate of the ultrafiltration membrane(5), a reverse osmosis filtration membrane(8) for removing organic material with low molecular weight, color inducing material, heavy metals, COD, ABS and TDS, and an adsorption basin(9) for removing residual color inducing material, a small amount of organic material, N-H, COD and ABS from the water passing out the reverse osmosis filtration membrane(8).

Description

Apparatus for recycling of machining wastewater by multi-stage filtering including membranes}

The present invention is a water quality suitable for reuse of the process wastewater generated in the machining process through a multi-stage pretreatment including oil-water separation, precoat filter, micro filter, two-stage membrane treatment of ultrafiltration and reverse osmosis, and the adsorption process of the back end activated carbon It relates to a device for processing.

Wastewater generated in the machining process includes cutting wastewater and cleaning wastewater used in the machining process. More specifically, in the machining process wastewater, waste chips, metal chips and nonmetal wastes generated during machining and product cleaning, Suspended solids, oil, surfactants and the like. Machining process wastewater containing such contaminants is difficult to general biological treatment and physical and chemical treatment by toxic from cutting oil and hardly degradable materials such as cutting oil and surfactant.

Therefore, existing machining companies require a large amount of process water in the washing and rinsing process, and even though expensive processing costs are consumed, most of them rely on consignment processing.

The present invention solves these conventional problems and introduces a process including multi-stage pretreatment and membrane treatment, which avoids inefficient and costly consignment treatment systems and reuses the wastewater, thereby effectively treating the wastewater, while Cutting amount of cutting oil, cleaning agent, etc. can be achieved.

In addition, the TDS in the process water is removed from the system while the membrane is treated, which improves the quality of the treated water. It can minimize the effects of stains and improve cleaning quality.

An object of the present invention is to solve the problems of the prior art, to effectively remove the contaminants in the waste water machining process using a multi-stage treatment process including pre-treatment and membrane treatment, high quality treated water that can be reused in the washing and rinsing process The purpose is to provide a device for producing a.

1. Raw water tank

2. Oil and Water Separation Tank

3. Precoat Filter

4. micro filter

5. Primary reservoir

6. Ultrafiltration membrane

7. Secondary reservoir

8. Reverse Osmosis Membrane

9. Activated carbon adsorption tank

10. First Return Line

11. 2nd Return Line

The present invention has a supply pipe for supplying the cutting waste water and the washing waste water generated in the machining process to the raw water tank (1), the oil and water separation tank (2) for separating the floating oil and SS components in the waste water introduced from the raw water tank (1) ; A precoat filter (3) which receives wastewater from the oil / water separation tank (2) and removes metal chips and nonmetallic debris, various suspended substances, oil, etc .; A cartridge type micro filter 4 which receives wastewater from the precoat filter 3 and removes suspended solids and contaminants of 5 μm or more in the wastewater; A primary reservoir 5 for storing the wastewater filtered by the micro filter 4; Ultrafiltration membrane (6) to receive the pre-processing process wastewater of the primary storage tank (5) to remove organic substances and chromaticity-inducing substances, N-H, COD, etc. having a large molecular weight; A secondary reservoir 7 for storing wastewater produced from the ultrafiltration membrane 6; A reverse osmosis membrane (8) for receiving the ultra-filtered wastewater of the secondary storage tank (7) to remove organic substances and chromaticity-inducing substances, heavy metals, COD, ABS, TDS and the like having low molecular weight; An activated carbon adsorption tank 9 for receiving the wastewater filtered by the reverse osmosis membrane 8 to remove residual chromaticity, trace organic matter, N-H, COD, ABS and the like in the wastewater; First and second return lines (10, 11) for transferring the concentrated water of the ultrafiltration membrane (6) and reverse osmosis membrane (8) to the primary reservoir (5).

Hereinafter, with reference to the accompanying drawings [FIG. 1] an embodiment of an apparatus for recycling wastewater in a machining process by multi-stage filtering including a pretreatment and a separator for the present invention.

As shown in Figure 1, the multi-stage filtering process of the wastewater recycling process using the present embodiment is a raw water tank (1); Oil and water separation tank (2); Precoat filter 3; Micro filter 4; Primary reservoir 5; Ultrafiltration membrane 6; Secondary reservoir 7; Reverse osmosis membrane (8); The activated carbon adsorption tank 9 is included.

Machining process wastewater includes cutting wastewater from general machining process and cleaning wastewater from washing and rinsing process.

The raw water tank 1 is connected to a supply pipe for supplying the machining process wastewater, and the process wastewater generated in the machining process through the supply pipe is stored in the raw water tank 1. The supplied process wastewater includes cutting wastewater generated during the molding of mechanical parts and cleaning waste water generated when washing and rinsing the molded products.The process wastewater contains oil, metal chips, nonmetal waste, and various suspended substances. This causes pollution loads such as SS, COD, NH, TDS, ABS, color, heavy metals in the waste water.

Waste water transferred from the raw water tank (1) is introduced into the oil and water separation tank (2). Contaminants of the light dense flotation oil and the flotation solids in the wastewater introduced from the raw water tank 1 to the oil water separation tank 2 are removed while passing through the oil water separation tank 2. The oil / water separation tank 2 removes the floating oil and the floating solids by solid-liquid separation of the introduced wastewater, and the wastewater from which the floating oil and the floating solids are removed is introduced into the precoat filter 3 along the transfer pipe.

The precoat filter 3 is equipped with a filter element made of woven filter cloth. The filter element is coated on the surface of the ceramic material, and the wastewater introduced from the oil and water separation tank 2 penetrates through the filter cloth coated with the ceramic material and is not removed from the oil and water separation tank 2. Remove relatively large particles such as dregs and oil. The wastewater which has passed through the filter media having the ceramic media coated thereon is transferred to the micro filter 4.

The micro filter 4 is equipped with a cartridge type micro filter element, which has a pore size of 5 mu m. Therefore, by removing the contaminants of 5㎛ or more of the uncontaminated contaminants in the wastewater introduced into the precoat filter (3) to minimize the pollution load imposed on the post-stage membrane treatment. Wastewater filtered by the micro filter 4 is introduced into the primary reservoir (5).

The primary reservoir (5) is a pre-treatment process of the oil-water separation tank (2), precoat filter (3), micro filter (4) and stores the machining process waste water from which contaminants are considerably removed. Machining process wastewater pretreated with the ultrafiltration separator 6 for the treatment of the membrane from the primary reservoir 5 is supplied, and to cope with a sudden flow rate change of the machining process wastewater supplied to the downstream ultrafiltration membrane 6. It acts as a buffer. The membrane concentrate water, which has been removed from the trailing ultrafiltration membrane 6 and the reverse osmosis membrane 8, is returned and stored in the primary reservoir 5 along the respective return lines 10 and 11.

The ultrafiltration membrane 6 receives ultra-prepared machining process wastewater from the primary storage tank 5 and performs ultrafiltration, and organic materials, chromaticity-inducing substances, N-H, etc. having high molecular weight are excluded and removed from the permeate. The ultrafiltration membrane used in the present invention uses a hydrophilic material and a molecular weight cut-off of 10,000 to 100,000 daltons uses a hollow fiber type ultrafiltration membrane having a diameter of 1.1 mm. The machining process wastewater transmitted from the ultrafiltration membrane 6 is transferred to the secondary storage tank 7 at the rear end and stored, and the concentrated concentrated water is discharged to the primary storage tank 5 along the primary return line 10. It is returned and stored.

The secondary storage tank (7) is stored from the ultrafiltration membrane 6, the organic permeate of large molecular weight, chromaticity-inducing material, N-H, COD and the like is supplied and stored. The secondary reservoir 7 supplies the ultrafiltration machined process wastewater to the reverse osmosis membrane 8 for the treatment of the machining process wastewater at the rear end reverse osmosis membrane 8, and is supplied to the reverse osmosis membrane 8. It acts as a buffer to flexibly cope with sudden changes in the flow rate of the machining process wastewater.

The reverse osmosis membrane (8) is supplied by the ultrafiltration membrane from the secondary storage tank (7) to receive a high molecular weight organic matter, chromate-inducing substances, NH, COD, etc. are excluded from the secondary storage tank (7) Organic materials and chromatic inducing substances, heavy metals, COD, ABS, TDS, etc. are excluded along with the concentrated water and permeate the treated water. The reverse osmosis membrane 8 used in the present invention uses a spiral wound reverse osmosis membrane having a molecular weight cut-off of 10 to 1000 daltons. Since the TDS removed by the reverse osmosis membrane 8 is a main component that causes stains on the surface of the product during the product washing process, the removal of the TDS improves the cleaning quality and also improves the quality of the product. In addition, the hardness component of the TDS is combined with the cleaning agent to reduce the cleaning ability and increases the consumption of the cleaning agent. Therefore, the removal of the TDS can significantly reduce the consumption of the detergent. The concentrated water removed from the reverse osmosis membrane 8 is transferred to and stored in the primary storage tank 5 along the secondary return line 11. In the reverse osmosis membrane 8, the organic permeate having a low molecular weight, chromaticity causing substances, heavy metals, COD, ABS, TDS, etc. are removed, and the treated permeate is transferred to the activated carbon adsorption tank 9.

The activated carbon adsorption tank (9) is permeated through the reverse osmosis membrane (8) is supplied with the processing process waste water is removed from the organic material and chromaticity-inducing substances, heavy metals, COD, ABS, TDS, etc. are removed. Due to the adsorption capacity of activated carbon, residual chromaticity, trace organic matter, N-H, COD, ABS, etc. are removed from the permeate treated with the reverse osmosis membrane 8, and water quality suitable for reuse is completed. The treated water passing through the activated carbon adsorption tank 9 is fed back into the washing process during the machining process as the final treated water and reused. The activated carbon adsorption tank 9 loses adsorption capacity after treating a certain amount of machining process wastewater, so it is necessary to periodically replace activated carbon.

According to the present invention, it is possible to effectively treat wastewater generated in the machining process and reuse it in the washing and rinsing process as well as greatly reducing the amount of process water used according to the reuse. In addition, by continuously removing TDS in the system, it prevents stains on the surface of the product due to TDS, thereby improving the cleaning quality of the product and greatly improving the quality of the product.

Claims (6)

In the re-use device of the machining process wastewater by multi-stage filtering including a separator, the raw water tank (1) to which the machining process wastewater flows; Oil-water separation tank (2) for separating the floating oil residue in the wastewater by introducing the machining process wastewater stored in the raw water tank; A precoat filter (3) for removing metal chips and nonmetallic debris, various suspended substances, oil, etc .; A cartridge-type micro filter 4 for removing contaminants of 5 μm or more passing through the precoat in waste water; A primary storage tank 5 into which the machining process wastewater filtered by the microfilter is introduced; Ultrafiltration membrane (6) to remove the organic matter, chromaticity-inducing substances, N-H, etc. having a large molecular weight by introducing the wastewater machining process of the primary storage tank; A secondary reservoir 7 for storing wastewater filtered by the ultrafiltration membrane; A reverse osmosis membrane (8) for introducing the ultra-filtered wastewater of the secondary storage tank to remove organic substances having low molecular weight, color causing substances, heavy metals, COD, ABS, TDS, etc .; Machine processing process wastewater recycling apparatus comprising an activated carbon adsorption tank (9) for introducing wastewater filtered by a reverse osmosis membrane to remove residual color in the wastewater, trace organic matter, N-H, COD, ABS and the like. The concentrate of the membrane removed from the ultrafiltration membrane (6) and the reverse osmosis membrane (8) according to claim 1 is transferred to the primary water tank (5) by the first return line (10) and the second return line (11). Apparatus characterized by being reprocessed Apparatus according to claim 1 comprising an oil separation tank (2), a precoat filter (3) and a micro filter (4). The method according to claim 1, wherein a ceramic system is used as a media of the precoat filter (3). The hollow fiber type ultrafiltration membrane according to claim 1, wherein the molecular weight cut-off of the hydrophilic material is 10,000 to 100,000 daltons. The method according to claim 1, wherein a spiral wound reverse osmosis membrane having a molecular weight cut-off of 10 to 1000 daltons is used.