CN102151440A - Composite filter pipe manufactured by expanded perlite and zeolite as main raw materials and manufacture method of composite filter pipe - Google Patents

Abstract

The invention discloses a composite filter tube with expanded perlite and zeolite as main raw materials and a preparation method thereof, in particular to a composite filter tube for material filtration or waste water treatment in the fields of environmental protection, food, light industry, medicine, chemical industry and the like. Filter tube and preparation method. The preparation method is as follows: mix expanded perlite and natural zeolite powder according to a certain ratio, and grind to 200-325 mesh to obtain base material; add pore-forming agent, melting agent and water-soluble adhesive to the base material, mix thoroughly, Prepare a semi-dry mixture; put the obtained semi-dry mixture into a separable rigid pipe mold, and centrifugally form a filter tube green body on a centrifugal molding machine; after the green body is demoulded, sintered and cooled to obtain expanded perlite/zeolite Composite filter. The present invention is characterized in that: perlite and natural zeolite are used as main raw materials, the preparation process is simple, and the manufacturing cost is low; the filter tube has high strength, pressure resistance, high temperature resistance, and wide application range; the continuous working time is long, easy to clean, and can be reused .

Description

A composite filter tube with expanded perlite and zeolite as main raw materials and its preparation method

technical field

The invention relates to the field of filtration, in particular to a composite filter tube with expanded perlite and zeolite as main raw materials for material filtration or wastewater treatment in the fields of environmental protection, food, light industry, medicine, chemical industry and the like and a preparation method thereof.

Background technique

Expanded perlite is a kind of porous white granular bulk material made of perlite ore preheated and roasted at high temperature. It can be used as filter material after crushing. As a traditional inorganic filter material, expanded perlite has been widely used in petroleum, chemical industry, light industry, preparation, water treatment and other fields. Natural zeolite is a kind of hydrous frame-like aluminosilicate mineral. Its internal structure is a three-dimensional space frame structure composed of silicon-oxygen tetrahedron and aluminum-oxygen tetrahedron. Holes and channels connected to the outside world (pore diameter 0.3~1nm). Therefore, natural zeolite can be used in environmental pollution control such as air purification, water pollution treatment, deodorization and antibacterial, solid waste treatment and catalyst carrier.

Expanded perlite and natural zeolite have the following advantages and disadvantages when used as filter materials:

1. Both perlite and natural zeolite are non-metallic minerals with wide sources, simple processing technology and low cost.

2. The chemical components of perlite and natural zeolite are mainly silicon and aluminum oxides, with stable chemical properties and a wide range of applications. It itself does not contain organic matter, has no harm to the human body, has no effect on the essential properties of the filtrate, and has no potential pollutants.

3. Expanded perlite filter aid is generally added to the material to be filtered, fully stirred, and then centrifugally filtered (drum filter) or press-filtered (plate-frame filter). There is a certain loss during use. The longer the filtration time, the higher the compactness of the filter cake, and the lower the filtration flux. In addition, since expanded perlite filter aids are generally used for one-time use, a large amount of filter aid waste will be generated.

4. Natural zeolite is mainly based on ion exchange due to its small internal pore size and low filtration flux. The ion exchange capacity of zeolite is not only related to the type of zeolite, but also related to the ratio of silicon to aluminum of zeolite, the size of pores in the crystal lattice, the dredging of pores, the position and nature of cations, and the temperature, pressure, ion concentration, and flow rate during the exchange process. It is related to many factors such as pH value.

my country's perlite and natural zeolite are rich in mineral resources, and have been applied in the fields of petroleum, chemical industry, light industry, pharmaceuticals, water treatment, etc. Therefore, it is an urgent problem to provide a method for preparing composite filter tubes with expanded perlite and zeolite as raw materials.

Contents of the invention

In order to overcome the deficiencies in the above-mentioned prior art, the present invention provides a kind of perlite and natural zeolite as the main raw material, the preparation process is simple, the manufacturing cost is low, pressure resistance, high temperature resistance, continuous working time is long, easy to clean, repeatable The composite filter pipe used and its preparation method.

The purpose of the present invention is achieved like this:

1, a kind of composite filter tube and preparation method that take expanded perlite and zeolite as main raw material, it is characterized in that, concrete preparation method step is as follows:

The first step: Take expanded perlite and natural zeolite with a mass ratio of 1:4~6, mix and grind to 200~325 mesh to obtain the base material;

The second step: Add pore-forming agent, melting agent, water-soluble adhesive and water to the base material prepared in the first step, and mix thoroughly to prepare a semi-dry mixture; adding pore-forming agent and fluxing agent The amount is 0.5~2% of the base material; the amount of adhesive added is 1~10%, the adhesive is dissolved in water in advance, and the amount of water added is preferably to hold the mixture by hand without water out;

Step 3: First, coat the inner wall of the pipe mold with a release agent, then put the semi-dry mixture obtained in the second step into a separable rigid pipe mold, place it on a centrifugal molding machine, and centrifugally form it into a green filter tube; centrifuge The rotational speed during molding is controlled at 1200~1500rpm, and the centrifugal molding time is controlled at 30~60min;

Step 4: Remove the rigid pipe mold from the centrifuge, open the pipe mold, and take out the green filter tube;

Step 5: Move the green body of the filter tube in the fourth step to a temperature-programmed furnace for roasting, and obtain the expanded perlite/zeolite composite filter tube after cooling. The roasting temperature system is as follows: heating rate is less than or equal to 5°C/min; 100~200°C for 60 minutes; 400~600°C for 30 minutes; 700~1000°C for 30 minutes.

The main raw materials used are expanded perlite and natural zeolite, with a particle size of 200-325 mesh; the filter holes of the composite filter tube are composed of base material expanded perlite, zeolite internal micropores and particle gaps.

The pore-forming agent used can be any one or a combination of several of methylcellulose, polyvinyl alcohol, vegetable starch, charcoal powder, sawdust powder, etc., and the amount added is 0.5-2% of the base material.

The flux used can be any one or a mixture of borax, sodium oxide, potassium oxide, etc., and the amount added is 0.5-2% of the base material.

The water-soluble adhesive used can be any one or a mixture of several of methylcellulose, polyvinyl alcohol, vegetable starch, bentonite, clay, etc., and the amount added is 1-10% of the base material.

The composite filter tube is formed by centrifugal molding, the speed of centrifugal forming is controlled at 1200-1500 rpm, and the time of centrifugal forming is controlled at 30-60 minutes.

The sintering temperature of the composite filter tube is not higher than 1000°C.

The present invention is characterized in that: the porosity of natural minerals is fully utilized, and the filter holes of the composite filter tube are composed of base material expanded perlite, zeolite internal micropores and particle gaps; semi-dry billet making, drying and sintering are completed at one time, saving energy Centrifugal molding, the compactness of the billet is easy to adjust, the pore diameter of the filter tube is distributed in a gradient from the inside to the outside, the inner surface pore size is small, the outer surface pore size is large, which can slow down the decrease in filtration flux during use; the filter tube has high strength and durability High pressure, high temperature resistance, wide range of use; long continuous working time, easy to clean and reusable.

Detailed ways

The present invention will be further described below in conjunction with specific embodiment:

The first step: Take expanded perlite and natural zeolite with a mass ratio of 1:4~6, mix and grind to 200~325 mesh to obtain the base material;

The second step: Add pore-forming agent, melting agent, water-soluble adhesive and water to the base material prepared in the first step, and mix thoroughly to prepare a semi-dry mixture; adding pore-forming agent and fluxing agent The amount is 0.5~2% of the base material; the amount of adhesive added is 1~10%, the adhesive is dissolved in water in advance, and the amount of water added is preferably to hold the mixture by hand without water out;

Step 3: First, coat the inner wall of the pipe mold with a release agent, then put the semi-dry mixture obtained in the second step into a separable rigid pipe mold, place it on a centrifugal molding machine, and centrifugally form it into a green filter tube; centrifuge The rotational speed during molding is controlled at 1200~1500rpm, and the centrifugal molding time is controlled at 30~60min;

Step 4: Remove the rigid pipe mold from the centrifuge, open the pipe mold, and take out the green filter tube;

Step 5: Move the green body of the filter tube in the fourth step to a temperature-programmed furnace for roasting, and obtain the expanded perlite/zeolite composite filter tube after cooling. The roasting temperature system is as follows: heating rate is less than or equal to 5°C/min; 100~200°C for 60 minutes; 400~600°C for 30 minutes; 700~1000°C for 30 minutes.

The purpose of adding the pore-forming agent in the above embodiment is to increase the gap between the mineral particles and increase the filtration flux of the filter tube. The added pore-forming agent can be any one or a combination of several of methylcellulose, polyvinyl alcohol, vegetable starch, charcoal powder, sawdust powder, etc.

The purpose of adding flux in the above embodiment is to reduce the sintering temperature of the filter tube blank. The added flux can be any one or a mixture of borax, sodium oxide, potassium oxide, etc.

The purpose of adding the water-soluble adhesive in the above embodiment is to increase the strength of the filter tube blank, which is convenient for demoulding and transfer to the roasting furnace. The added water-soluble binder can be any one or a combination of several of methylcellulose, polyvinyl alcohol, vegetable starch, bentonite, clay, etc.

The present invention is characterized in that: the porosity of natural minerals is fully utilized, and the filter holes of the composite filter tube are composed of base material expanded perlite, zeolite internal micropores and particle gaps; semi-dry billet making, drying and sintering are completed at one time, saving energy Centrifugal molding, the compactness of the billet is easy to adjust, the pore diameter of the filter tube is distributed in a gradient from the inside to the outside, the inner surface pore size is small, the outer surface pore size is large, which can slow down the decrease in filtration flux during use; the filter tube has high strength and durability High pressure, high temperature resistance, wide range of use; long continuous working time, easy to clean and reusable.

Example 1:

1. Mix expanded perlite and natural zeolite powder at a ratio of 1:4 (by weight), and grind to 325 mesh to obtain the base material.

2. Add 1% starch, 2% borax, and 10% bentonite to the base material, mix thoroughly, add an appropriate amount of water, and mix evenly to obtain a semi-dry mixture.

3. First coat the inner wall of the Φ50×200 separable rigid pipe mold with a release agent, then put the obtained semi-dry mixture into it, place it on a centrifugal molding machine, control the speed at 1200 rpm, and centrifuge for 50 minutes to obtain a filter tube green body.

4. Remove the rigid tube mold from the centrifuge, open the tube mold, and take out the green filter tube.

5. Move the green filter tube to the temperature-programmed furnace, heat up to 100°C for 60 minutes at a heating rate of 5°C/min, hold for 30 minutes at 500°C, and hold for 30 minutes at 800°C, and then naturally cool in the furnace to obtain expanded perlite / Zeolite composite filter tube.

Example 2:

1. Mix expanded perlite and natural zeolite powder at a ratio of 1:5 (weight ratio), and grind to 325 mesh to obtain the base material.

2. Add 1.5% starch, 1.5% borax, and 5% bentonite to the base material, mix thoroughly, add an appropriate amount of water, and stir evenly to obtain a semi-dry mixture.

3. First coat the inner wall of the Φ50×200 separable rigid pipe mold with a release agent, then put the obtained semi-dry mixture into it, place it on a centrifugal molding machine, control the speed at 1500 rpm, and centrifuge for 30 minutes to obtain a filter tube green body.

4. Remove the rigid tube mold from the centrifuge, open the tube mold, and take out the green filter tube.

5. Move the green filter tube to the temperature-programmed furnace, heat up to 120°C for 60 minutes at a heating rate of 5°C/min, keep at 600°C for 30 minutes, and hold at 850°C for 30 minutes. After natural cooling in the furnace, the expanded perlite is obtained. / Zeolite composite filter tube.

Example 3:

1. Mix expanded perlite and natural zeolite powder at a ratio of 1:6 (weight ratio), and grind to 325 mesh to obtain the base material.

2. Add 2% starch, 1% borax, and 0.5% sodium oxide to the base material, then dissolve 5g of polyvinyl alcohol with an appropriate amount of hot water, add it, and stir evenly to obtain a semi-dry mixture.

3. First coat the inner wall of the Φ50×200 separable rigid pipe mold with a release agent, then put the obtained semi-dry mixture into it, place it on a centrifugal molding machine, control the speed at 1400 rpm, and centrifuge for 40 minutes to obtain a filter tube green body.

4. Remove the rigid tube mold from the centrifuge, open the tube mold, and take out the green filter tube.

5. Move the green filter tube to the temperature-programmed furnace, heat up to 120°C for 60 minutes at a heating rate of 5°C/min, hold for 30 minutes at 700°C, and hold for 30 minutes at 900°C, and then naturally cool in the furnace to obtain expanded perlite / Zeolite composite filter tube.

The above examples are only used to illustrate preferred implementations of the present invention, but the present invention is not limited to the above-mentioned implementations, within the scope of knowledge possessed by those of ordinary skill in the art, any modifications made within the spirit and principles of the present invention , equivalent replacements and improvements, etc., all of which shall be covered within the scope of the technical solution claimed in the present invention.

Claims (7)

1. one kind is the composite filter tube and the preparation method of primary raw material with expanded perlite and zeolite, it is characterized in that, concrete preparation method's step is as follows:

The first step: getting expanded perlite and natural zeolite mass ratio is 1:4 ~ 6, and combined grinding to 200 ~ 325 orders obtains base-material;

Second step: in the prepared base-material of the first step, add pore creating material, flux, water soluble adhesive and water, fully mix, be prepared into half-dried compound; The addition of pore creating material and flux is respectively 0.5 ~ 2% of base-material; The bonding agent addition is 1 ~ 10%, the dissolving of the prior water of bonding agent, and amount of water is held the agglomerating but not water outlet of compound with final usefulness and is advisable;

The 3rd step: earlier the pipe die inwall is coated releasing agent, in the separable rigidity pipe die of the more half-dried compound of the second step gained being packed into, be placed on the centrifugal shaper, centrifugal forming is the chimney filter green compact; Rotating speed is controlled at 1200 ~ 1500rpm during centrifugal forming, and the centrifugal forming time is controlled at 30 ~ 60min;

The 4th step: the rigidity pipe die is taken off from centrifuge, open pipe die, take out the chimney filter green compact;

The 5th step: the chimney filter green compact in the 4th step are moved to the temperature programming kiln roasting, promptly obtain expanded perlite/zeolite composite filter tube after the cooling; The sintering temperature system is: programming rate is less than or equal to 5 ℃/min; 100 ~ 200 ℃ of insulation 60min; 400 ~ 600 ℃ of insulation 30min; 700 ~ 1000 ℃ of insulation 30min.

2. according to claim 1 a kind of be the composite filter tube and the preparation method of primary raw material with expanded perlite and zeolite, it is characterized in that: used primary raw material expanded perlite and natural zeolite, granularity is at 200 ~ 325 orders; The composite filter tube filter opening is made up of base-material expanded perlite, zeolite inside self micropore and particle gap.

3. according to claim 1 a kind of be the composite filter tube and the preparation method of primary raw material with expanded perlite and zeolite, it is characterized in that: used pore creating material can be any or several mixing in methylcellulose, polyvinyl alcohol, plant amylum, charcoal powder, the sawdust powder etc., and addition is 0.5 ~ 2% of a base-material.

4. according to claim 1 a kind of be the composite filter tube and the preparation method of primary raw material with expanded perlite and zeolite, it is characterized in that: used flux can be any or several mixing in borax, sodium oxide molybdena, the potassium oxide etc., and addition is 0.5 ~ 2% of a base-material.

5. according to claim 1 a kind of be the composite filter tube and the preparation method of primary raw material with expanded perlite and zeolite, it is characterized in that: used flux water soluble adhesive can be any or several mixing in methylcellulose, polyvinyl alcohol, plant amylum, bentonite, the clay etc., and addition is 1 ~ 10% of a base-material.

6. according to claim 1 a kind of be the composite filter tube and the preparation method of primary raw material with expanded perlite and zeolite, it is characterized in that: described composite filter tube adopts centrifugal forming, rotating speed is controlled at 1200 ~ 1500rpm during centrifugal forming, and the centrifugal forming time is controlled at 30 ~ 60min.

7. according to claim 1 a kind of be the composite filter tube and the preparation method of primary raw material with expanded perlite and zeolite, it is characterized in that: the firing temperature of described composite filter tube is not more than 1000 ℃.