KR20170026780A

KR20170026780A - Filter plate for filter press

Info

Publication number: KR20170026780A
Application number: KR1020150121232A
Authority: KR
Inventors: 우현직; 송태규; 이민철; 김영선; 김영곤; 심상은
Original assignee: (주)동일캔바스엔지니어링; 인하대학교 산학협력단
Priority date: 2015-08-27
Filing date: 2015-08-27
Publication date: 2017-03-09
Also published as: KR101818433B1

Abstract

The present invention provides a filter plate for a filter press made of a mixture of a ceramic filler and a polymer resin. The ceramic filler may be at least one selected from the group consisting of silica, glass fiber, calcium carbonate, carbon black, limestone powder and kaolin. The polymer resin may be at least one selected from the group consisting of polypropylene, polyethylene, polystyrene, polyester, acrylonitrile butadiene styrene , Polycarbonate, and nylon. The ceramic filler is dispersed in the course of mixing with the polymer resin, thereby improving the tensile strength of the filter plate for the filter press.

Description

{FILTER PLATE FOR FILTER PRESS}

The present invention relates to a filter plate for a filter press, and more particularly to a filter plate for a filter press having excellent mechanical strength and chemical resistance.

At present, the sewage discharged from homes and factories is sent to the sewage treatment plant and processed. The sewage treatment process includes a purification process and a sludge treatment process. In the purification process, the sewage is purified to a range where the self-purification of the river can be activated and discharged to a public water such as a river. In the sludge treatment process, The sludge is treated through processes such as concentration and dehydration.

A dehydrator, which is one of the devices used in the sludge treatment process, separates the filtrate from the sludge and is classified into a belt press, a filter press, a screw press, a centrifugal dehydrator, and an electroosmotic dehydrator according to the operation principle. Among them, the filter press is a device for removing the sludge cake (filtrate and separated sludge) from the compartment after pressurizing the compartment sludge provided between the filter plates which are in close contact with each other to separate the filtrate from the sludge.

In the filter press, the pressure of the sludge is applied to the filter plates during dehydration of the sludge, and the pressure input to the filter plates is released when the dehydration of the sludge is completed. Therefore, in the filter press, the action and release of high pressure on the filter plate are repeatedly performed, and the filter plate of the filter press needs to have a mechanical strength capable of withstanding repeated pressure changes. In addition, since the filter plate of the filter press is inevitably in constant contact with the organic / inorganic wastewater and air, it is also necessary to provide chemical resistance.

Korean Patent Laid-Open No. 10-2008-0018168 (Membrane plate for filter press) Korean Patent Laid-Open No. 10-2008-0018167 (Chamber Filter Plate) Korean Patent Laid-Open No. 10-2008-0011295 (heating and cooling filter plate)

SUMMARY OF THE INVENTION The present invention has been made in view of the above needs, and it is an object of the present invention to provide a filter plate for a filter press having excellent mechanical strength and chemical resistance, more specifically, a material for the filter plate.

When calcium carbonate and glass fiber are used as the ceramic filler, the weight of the calcium carbonate is preferably in the range of 1 to 6 times the weight of the glass fiber. Then, the tensile strength of the filter plate for the filter press can be set within the range of 48.72 MPa to 58.61 MPa, which is larger than the tensile strength of the filter plate for the filter press made of only polymer, which is 47.31 MPa. At this time, the content of the ceramic filler with respect to the mixture is preferably in the range of 10 wt% to 20 wt%, and if it is out of this range, the tensile strength may be lower than that of the filter plate made of only polymer.

The ceramic filler may be surface treated with a ceramic surface treatment agent selected from the group consisting of APS, EHTMS, MPA and VTMS. The ceramic surface treatment agent serves to help the ceramic filler to be more uniformly dispersed.

When the ceramic filler is a surface-treated silica, the content of the ceramic filler in the mixture is preferably 20 wt%. Then, the tensile strength of the filter plate for the filter press can be formed within the range of 51.86 MPa to 52.88 MPa, which is larger than the tensile strength of the filter plate for the filter press made of only polymer.

When the surface-treated silica and the glass fiber are used as the ceramic filler, the weight of the glass fiber is preferably in the range of 1 to 2 times the weight of the surface-treated silica. In this case, the tensile strength of the filter plate for the filter press can be formed within the range of 53.68 MPa to 81.46 MPa, which is larger than the tensile strength of the filter plate for the filter press made of only a polymer material. At this time, it is preferable that the content of the ceramic filler to the mixture is in the range of 10 wt% to 40 wt%, otherwise the tensile strength of the filter plate for the filter press made of only polymer may be lowered.

When the surface-treated silica and the glass fiber are used as the ceramic filler, the weight of the surface-treated silica may be in the range of 2 to 4 times the weight of the glass fiber. In this case, the tensile strength of the filter plate for the filter press can be formed within the range of 49.89 MPa to 65.56 MPa. At this time, it is preferable that the content of the ceramic filler in the mixture is in the range of 10 wt% to 30 wt%, otherwise the tensile strength of the filter plate for the filter press made of only polymer can be lowered.

The filter plate for a filter press according to the present invention has excellent tensile strength and chemical resistance as compared with a filter plate for a filter press made of only polymer water.

1 shows the results of tensile strength test and chemical resistance test of the composite specimen according to Example 1 of the present invention.
2 shows the results of the tensile strength test and the chemical resistance test of the composite specimen according to Example 2 of the present invention.
3 shows the results of tensile strength test and chemical resistance test of the composite specimen according to Example 3 of the present invention.
4 shows the results of the tensile strength test and chemical resistance test of the composite specimen according to Example 4 of the present invention.

Hereinafter, preferred embodiments of the filter plate for a filter press according to the present invention will be described in detail. It is to be understood that the terminology or words used herein are not to be construed in an ordinary sense or a dictionary, and that the inventor can properly define the concept of a term to describe its invention in the best possible way And should be construed in accordance with the meaning and concept consistent with the technical idea of the present invention.

Example 1 (surface treated silica / polypropylene composite)

160 g of methanol having a purity of 99.9%, 9 g of acetic acid, and 1 g of APS (N-2- (aminoethyl) -3-aminopropyltrimethoxysilane) as a ceramic surface treatment agent were stirred for 30 minutes to prepare a mixed solution. Then, 20 g of silica having a diameter of 6 micrometers was added to the mixed solution, stirred for 2 hours, and then silica was filtered out and dried. During the drying process, both methanol and acetic acid are vaporized, and APS chemically reacts with silica and remains on the surface of silica.

11 g of the surface-treated 6-micrometer-diameter silica was mixed with 44 g of pellet-shaped polypropylene in an airtight mixer at a temperature of 220 ° C and a screw rotation speed of 100 rpm for 15 minutes to form a composite And the silica content was 20 wt%). The composite was placed in a stainless steel mold, and thermocompression was performed at 220 ° C and 4600 psi to prepare a composite specimen. In addition, two composite specimens were further prepared by replacing only the ceramic surface treatment agent with EHTMS and MPA while keeping the other conditions intact.

EHTMS (2- (3, 4epoxycyclohexyl) ethyltrimethoxysilane)

MPA (3-methacryloxypropyltrimethoxysilane)

The tensile strength test and the chemical resistance test were performed on the three composite specimens prepared as described above, and the results are shown in FIG. The tensile strength test was conducted according to ASTM D638-10. In the chemical resistance test, if the tensile strength of the composite specimen immersed in anaerobic wastewater for 2 months decreased to within 7% of the tensile strength of the composite specimen before immersing, it was judged to pass or fail.

Referring to FIG. 1, it can be seen that the composite specimens according to the present embodiment have a tensile strength in the range of 51.86 MPa to 52.58 MPa. Also, referring to FIG. 1, it can be seen that the chemical compositions of the composite specimens according to the present embodiment are all acceptable.

Example 2 (silica / polypropylene / Surface treatment agent Complex)

11 g of silica having a diameter of 6 micrometers, 44 g of polypropylene in the form of pellets, and 0.55 g of APS were mixed in a closed mixer at a temperature of 220 DEG C and a screw rotating speed of 100 rpm for 15 minutes and then dried to form a composite. APS chemically reacts with silica in the mixing process and remains on the surface of silica, and unreacted APS is vaporized during the drying process.

The composite (20 wt% silica content of the composite) was put into a stainless steel mold and thermocompression bonded at 220 ° C and 4600 psi to prepare a composite specimen. In addition, two composite specimens were further prepared by replacing only the ceramic surface treatment agent with EHTMS and MPA while keeping the other conditions intact.

The tensile strength test and the chemical resistance test were carried out on the three composite specimens prepared as described above, and the results are shown in Fig. The tensile strength test and the chemical resistance test were carried out in the same manner as in Example 1.

Referring to FIG. 2, the composite specimens according to the present embodiment have a tensile strength in the range of 51.99 MPa to 52.88 MPa. In addition, referring to FIG. 2, it can be seen that the chemical resistance of the composite specimens according to the present embodiment is all acceptable.

Example 3 (silica / glass fiber / polypropylene / Surface treatment agent Complex)

6 g of silica with a diameter of 6 micrometers, 12 g of glass fiber glass strand masterbatch (90% of glass fiber weight), 42 g of polypropylene in the form of pellets and 0.3 g of APS were mixed in a closed mixer at a temperature of 220 캜 and a screw rotation speed of 100 rpm Minute, followed by drying to form a complex. APS chemically reacts with silica in the mixing process and remains on the surface of silica, and unreacted APS is vaporized during the drying process.

These composites (silica and glass fiber weight ratio 1: 2, silica and glass fiber content 30wt% to the composite) were placed in a stainless steel mold and thermocompression bonded at 220 ° C and 4600 psi to produce composite specimens. Three composite specimens were further prepared by replacing only the ceramic surface treatment agent with EHTMS, MPA, and VTMS (Vinyltrimethoxysilane) while the other conditions remained unchanged.

The tensile strength test and the chemical resistance test were carried out on the four composite specimens thus prepared in the same manner as in Example 1, and the results are shown in Fig. Referring to FIG. 3, it can be seen that the above four composite specimens have a tensile strength in the range of 68.18 MPa to 73.15 MPa, and the chemical resistance is all acceptable.

On the other hand, in the present embodiment, the ceramic surface treatment agent was changed to APS and the 11 kinds of silica-glass fibers having a silica diameter of 6 micrometers and a weight ratio of silica and glass fiber, Composite specimens were further prepared, and tensile strength tests and chemical resistance tests were carried out for each composite specimen in the same manner as in Example 1.

Of these 11 composite specimens, the silica and glass fiber contents were 40 wt%, the weight ratio of silica to glass fiber was 2: 1, the content of silica and glass fiber was 40 wt%, and the weight ratio of silica and glass fiber was 4: 1, the tensile strength in the range of 49.89 MPa to 81.46 MPa is shown in FIG. In addition, it can be seen that the chemical resistance of the above 11 composite specimens are all acceptable.

Example 4 (calcium carbonate / glass fiber / polypropylene composite)

6 g of calcium carbonate, 6 g of a glass fiber cord strand master batch (90% of glass fiber weight) and 48 g of pellet-shaped polypropylene were mixed in a closed type mixer at 220 캜 and 100 rpm screw rotation speed for 15 minutes to form a composite. Then, this composite (calcium carbonate and glass fiber weight ratio 1: 1, calcium carbonate and glass fiber content 20wt% for the composite) was placed in a stainless steel mold and thermocompression bonded at 220 ° C. and 4600 psi to prepare a composite specimen. In addition, one composite specimen was prepared by changing the content of calcium carbonate and glass fiber to 10 wt%, while keeping the other conditions intact. Six composite specimens were also prepared by changing the weight ratio of calcium carbonate to glass fiber to 2: 1, 4: 1 and 6: 1 for each of the two composites.

The tensile strength test and the chemical resistance test were conducted on the eight composite specimens thus prepared in the same manner as in Example 1, and the results are shown in FIG. Referring to FIG. 4, it can be seen that the above eight composite specimens have a tensile strength in the range of 48.72 MPa to 58.61 MPa, and the chemical resistance is all acceptable.

Comparative Example (Polypropylene)

52 g of pelletized polypropylene was mixed in a closed mixer at a temperature of 220 ° C and a screw rotation speed of 100 rpm for 7 minutes. The mixture was placed in a stainless steel mold and thermocompression-bonded at 220 ° C. and 4600 psi to prepare a polypropylene sample.

The tensile strength test and the chemical resistance test were carried out on the polypropylene sample thus prepared in the same manner as in Example 1. As a result, it was confirmed that the polypropylene sample had a tensile strength of 47.31 MPa and the chemical resistance was confirmed to be acceptable .

The tensile strength of the polypropylene specimen is smaller than the tensile strength of the three composite specimens of Example 1, the tensile strength of the three composite specimens of Example 2 and the tensile strength of the eight composite specimens of Example 4. The tensile strengths of the polypropylene specimens were the same as in Example 3 except that two of the fifteen composite specimens of Example 3 (having a silica and glass fiber content of 40 wt% and a weight ratio of silica to glass fiber of 2: 1, Is 40 wt% and the weight ratio of silica to glass fiber is 4: 1) than the tensile strength of the 13 composite specimens.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It is to be understood that various changes and modifications may be made without departing from the scope of the appended claims.

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Claims

A mixture of a ceramic filler and a polymer resin,
Wherein the ceramic filler is at least one selected from the group consisting of silica, glass fiber, calcium carbonate, carbon black, limestone powder and kaolin, and the polymer resin is selected from the group consisting of polypropylene, polyethylene, polystyrene, polyester, acrylonitrile butadiene styrene, A filter plate for a filter press employing one or more of the group consisting of carbonates and nylons.

The method according to claim 1,
Wherein when calcium carbonate and glass fiber are used as the ceramic filler, the weight of the calcium carbonate is in the range of 1 to 6 times the weight of the glass fiber.

3. The method of claim 2,
Wherein the content of the ceramic filler in the mixture is in the range of 10 wt% to 20 wt%.

The method according to claim 1,
Wherein the ceramic filler is surface treated with a ceramic surface treatment agent selected from the group consisting of APS, EHTMS, MPA and VTMS.

5. The method of claim 4,
Wherein when the ceramic filler is a surface-treated silica, the content of the ceramic filler relative to the mixture is 20 wt%.

5. The method of claim 4,
Wherein when the surface-treated silica and glass fiber are used as the ceramic filler, the weight of the glass fiber is in the range of 1 to 2 times the weight of the surface-treated silica.

The method according to claim 6,
Wherein the content of the ceramic filler in the mixture is in the range of 10 wt% to 40 wt%.

5. The method of claim 4,
Wherein when the surface-treated silica and glass fiber are used as the ceramic filler, the weight of the surface-treated silica is in the range of 2 to 4 times the weight of the glass fiber.

9. The method of claim 8,
Wherein the content of the ceramic filler in the mixture is in a range of 10 wt% to 30 wt%.