CN112546854B - Selective thermal sintering molding 3D printing dioxin removal bag cage and preparation method thereof - Google Patents

Abstract

The invention discloses a selective thermal sintering molding 3D printing dioxin removal bag cage and a preparation method thereof, which take dioxin removal catalytic powder, polytetrafluoroethylene powder, nano silicon dioxide and dioctyl phthalate as raw materials, obtain a 3D printing material after ball milling, melting, stirring and extrusion granulation, and prepare the dioxin removal bag cage by a selective thermal sintering 3D printing technology; the bag cage prepared by the invention can support the filter bag more fully and uniformly, further reduces the stress on the surface of the filter bag and can effectively prolong the service life of the filter bag; meanwhile, as the bag cage is fully distributed with a considerable number of micropores, through tests, the resistance of the combination of the conventional filter bag and the dioxin removal bag cage is smaller than that of the combination of the dioxin removal filter bag and the conventional bag cage; is convenient for industrial scale production and has high engineering application value.

Description

A kind of selective thermal sintering forming 3D printing dedioxin bag cage and its preparation method

technical field

The invention belongs to the technical field of waste incineration flue gas purification, and in particular relates to a selective thermal sintering forming 3D printing dioxin-free bag cage and a preparation method thereof.

Background technique

Waste incineration power generation is an important way to solve the siege of waste. Among them, the purification of waste incineration flue gas is the focus of research in recent years, and the removal of dioxins from flue gas is the top priority of waste incineration flue gas purification. Filter bag dioxin removal is a new flue gas dioxin removal technology. With the help of a filter bag with catalytic function, the bag type dust removal process is used to achieve flue gas dioxin removal at low temperature. At present, only U.S. Gore Company has a mature and applied catalytic filter bag product (US005620669). This technology has been successfully applied in foreign waste incineration flue gas treatment, but it is expensive and difficult to develop. At present, the preparation method of the domestic de-dioxin filter bag is mainly the dipping method (CN110465288A, CN110898829A). Although the above method can prepare the dioxin-removing filter material, there are usually poor dispersibility of the dioxin-removing active components, and the combination strength of the catalyst and the filter bag fiber is weak, resulting in a low efficiency of the filter bag to remove dioxins and a long service life. Short, which greatly limits its engineering applications.

Contents of the invention

The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art, and provide a method for preparing a dioxin-removing bag cage, jumping out of the framework of filter bag removal of dioxins, changing the thinking, and using 3D printing technology to load the catalyst on the filter. On the bag cage, a dioxin-removing and dust-removing integrated bag cage with a dioxin-removing function was prepared.

In order to achieve the above purpose, the present invention adopts the following technical scheme: a method for preparing a selective thermal sintering molding 3D printing de-dioxin bag cage, comprising the following steps:

(1) By weight, 55-80 parts of dioxin-removing catalyst powder, 15-35 parts of polytetrafluoroethylene powder, 1-8 parts of monoalkoxy titanate and 4-12 parts of nano-silica After mixing, carry out ball milling, and then undergo melting treatment to obtain material A, then add 0.2 to 4 parts of dioctyl phthalate to the material A, and then extrude and granulate after stirring to obtain printing materials for 3D printing;

(2) Create a three-dimensional model of the dioxin-removing bag cage. The main body of the dioxin-removing bag cage is a straight cylinder with micropores, and the bottom of the straight cylinder is also provided with micropores, and the diameter of the micropores and the distance between the micropores are set;

(3) slice the dioxin-free cage three-dimensional model created in step (2), set the layer height and wall thickness, and obtain a three-dimensional model of the dioxin cage that can be printed;

(4) 3D printing adopts the selective thermal sintering method. Firstly, the prepared powder is evenly spread on the operating table by the powder spreading roller, and the operating table is preheated at the same time, and then the moving speed and power of the printing head are set. The 3D model of the dioxin bag cage that can be printed is 3D printed;

(5) After the printing is finished, it is cooled and shaped, and the unsintered powder is removed after cooling and shaped, and finally the dioxin-free bag cage is obtained.

In the step (1), add manganese nitrate, cerium nitrate hexahydrate and cobalt sulfate heptahydrate into deionized water in a mass ratio of 1.5:2.1:1, stir to form a solution, add ammonia water dropwise to the solution to control the pH value to 8.2 until the precipitation is completed , followed by filtration and drying to obtain the precursor powder, and then the precursor powder was roasted in the air at 400°C for 4 hours, and then ground and sieved to make 1200 mesh particles to obtain the dedioxin powder catalytic powder.

The particle size of the polytetrafluoroethylene powder in the step (1) is 500nm-50μm.

The particle size of the 3D printing material in the step (1) is 25-100 μm.

The melting temperature in the step (1) is 380-400°C.

The diameter of micropores in the three-dimensional model of the dioxin-removing bag cage in the step (2) is 2-10 mm, and the distance between micropores is 4-15 mm.

In the step (3), the height of the middle layer is 0.2-1 mm, the wall thickness is 0.1-0.3 mm, the diameter of the pores is 2-10 mm, and the distance between the pores is 4-15 mm.

In the step (4), the moving speed of the printing head is 1000-4000mm/min, and the power is 5-30W.

A dioxin-removing bag cage, prepared based on the method of the present invention, the main body is a straight cylinder with micropores, the bottom of the straight cylinder is the bottom of the cage, and micropores are arranged on the bottom of the cage, the diameter of the micropores is 2-10mm, The hole spacing is 4-15mm.

The top of the straight cylinder is provided with a flanging type upper ring opening.

Compared with the prior art, the present invention has the following beneficial technical effects:

(1) The present invention makes the functions of the dioxin-removing filter bag and the bag cage cleverly coexist in one main body, the catalyst can be well attached in the bag cage, and fully exerts the catalytic performance. The support of the filter bag is more sufficient and uniform, which further reduces the force on the surface of the filter bag and can effectively prolong the life of the filter bag; at the same time, the bag cage is covered with a considerable number of micropores. Compared with the combination of dioxin removal filter bag and conventional bag cage, the resistance of the oxin bag cage combination is smaller;

(2) The bag cage of the present invention is to implant the catalyst for removing dioxin into the bag cage for removing dioxin through raw material blending, so that the loading capacity of the catalyst on the bag cage is large, and the catalyst is more evenly distributed in the bag cage. Greatly improve the efficiency of removing dioxins.

(3) Among the raw materials of the present invention, polytetrafluoroethylene has good adhesion to the pair, and can play a good main body support effect on the bag cage after molding, while utilizing the good hydrophobicity of polytetrafluoroethylene It can prevent the catalytic performance of the catalyst powder from excessive contact with water and reduce the catalytic performance; the monoalkoxy titanate can improve the oxidation resistance of the bag cage and help to prolong the life of the catalyst. In addition, it can also improve the catalyst powder, The bonding strength between PTFE powder and nano-silica, and nano-silica has a good reinforcing effect on the bag cage;

(4) The present invention adopts the selective thermal sintering 3D printing method to prepare the dioxin-free bag cage. The size of micropores in the bag cage can be set according to the requirements, and there is almost no difficulty in preparation, which can fully Play the limit of structural optimization design, taking into account gas resistance and removal efficiency.

The bag cage prepared by the present invention organically combines functions and structures in one main body, that is, the dioxin can be removed by using the bag cage according to the present invention in combination with a common filter bag, and the bag cage prepared by the present invention has a significant effect on the filter bag. The support is more sufficient and uniform, which further reduces the force on the surface of the filter bag and can effectively prolong the life of the filter bag; the bag cage is covered with a considerable number of micropores. After testing, the conventional filter bag plus the application of the dioxin removal bag cage Compared with the combination of de-dioxin filter bag and conventional bag cage, the combination has lower resistance.

Description of drawings

Fig. 1 is a schematic diagram of an implementable dioxin removal bag cage model.

Fig. 2 is a top view schematic diagram of a dioxin-removing bag cage.

Fig. 3 is a schematic side view of a bag cage for removing dioxins.

In the figure: 1 upper ring mouth, 2 microholes, 3 microhole spacing, 4 cage bottom.

Detailed ways

The present invention will be described in detail below in conjunction with the examples.

Referring to Figure 1, Figure 2 and Figure 3, a selective thermal sintering molding 3D printing de-dioxin bag cage and its preparation method include the following steps:

(1) By weight, 55-80 parts of dioxin-removing catalyst powder, 15-35 parts of polytetrafluoroethylene powder, 1-8 parts of monoalkoxy titanate and 4-12 parts of nano-silica After mixing, carry out ball milling, and then undergo melting treatment to obtain material A, then add 0.2 to 4 parts of dioctyl phthalate to the material A, and then extrude and granulate after stirring to obtain printing materials for 3D printing;

(2) Create a three-dimensional model of the dioxin-removing bag cage. The main body of the dioxin-removing bag cage is a straight tube provided with micropores 2, and the diameter of the micropores and the distance between the micropores are set;

(3) slice the dioxin-free cage three-dimensional model created in step (2), set the layer height and wall thickness, and obtain a three-dimensional model of the dioxin cage that can be printed;

(4) 3D printing adopts the selective thermal sintering method. Firstly, the prepared powder is evenly spread on the operating table by the powder spreading roller, and the operating table is preheated at the same time, and then the moving speed and power of the printing head are set. The 3D model of the dioxin bag cage that can be printed is 3D printed;

(5) After the printing is finished, it is cooled and shaped, and the unsintered powder is removed after cooling and shaped, and finally the dioxin-free bag cage is obtained.

In the step (1), add manganese nitrate, cerium nitrate hexahydrate and cobalt sulfate heptahydrate into deionized water in a mass ratio of 1.5:2.1:1, stir to form a solution, add ammonia water dropwise to the solution to control the pH value to 8.2 until the precipitation is completed , followed by filtration and drying to obtain the precursor powder, and then the precursor powder was roasted in the air at 400°C for 4 hours, and then ground and sieved to make 1200 mesh particles to obtain the dedioxin powder catalytic powder.

The particle size of the polytetrafluoroethylene powder in the step (1) is 500nm-50 μm; the particle size of the 3D printing material in the step (1) is 25-100 μm; the melting temperature in the step (1) is 380-400°C;

Step (2) The micropore diameter in the dioxin-removing bag cage three-dimensional model is 2-10mm, and the micropore spacing is 4-15mm;

In step (3), the height of the middle layer is 0.2-1mm, the wall thickness is 0.1-0.3mm, the diameter of the micropores is 2-10mm, and the distance between the micropores is 4-15mm.

In step (4), the moving speed of the printing head is 1000-4000mm/min, and the power is 5-30W.

A dioxin-removing bag cage, prepared based on the method of the present invention, the main body is a straight cylinder provided with micropores 2, the bottom of the straight cylinder is a cage bottom 4, and micropores 2 are arranged on the cage bottom 4, and the diameter of the micropores is 2 ～10mm, the microhole spacing 3 is 4～15mm;

It should be noted that the micropores in the present invention are not necessarily regular circles, and the diameter of the micropores is the average value of all radial distances of the micropores.

Comply with described general plan, carry out following several implementations:

Example 1

After mixing 7.2kg of dioxin-removing catalyst powder, 3.1kg of polytetrafluoroethylene powder, 0.4kg of monoalkoxy titanate, and 0.6kg of nano-silicon dioxide, they are placed on a planetary ball mill for ball milling at a speed of 220r /min, every 20min is a round, and there are 5 rounds of grinding, that is, the ball milling time is 100min. Then melt processing at 380° C. to obtain material A, then add 0.058 kg of dioctyl phthalate to the material A, stir to obtain material B, and then extrude powder particles with an average particle size of 5 μm through a granulator, Obtain printing materials that can be used by 3D printing equipment; use Solidworks software to create a 3D model of the bag cage. The size of the substrate is: the diameter of the upper ring is 145mm, the thickness is 5mm, the diameter of the bottom is 110mm, the length of the bag cage is 970mm, and the diameter of the micropore is 3mm. Microhole spacing 5mm. Use Simplify 3D software to slice the created dioxin-free bag cage 3D model, set the layer height to 0.2mm, and the wall thickness to 0.1mm; 3D printing adopts selective thermal sintering technology, firstly, the prepared powder is passed through powder coating The rollers are evenly laid on the operation table, and the operation table is preheated to 260°C at the same time, and then the printing head moving speed is set to 2000mm/min and the power is 30W, and the 3D printing is carried out according to the modeling; after the printing is completed, it is shaped at 100°C and cooled Finally, the unsintered excess powder is removed, and finally the de-dioxin bag cage is obtained.

The obtained dioxin removal bag cage was evaluated on the SCR dioxin removal test bench using simulated flue gas to evaluate the dioxin removal performance. The flue gas at the inlet and outlet of the reactor was collected and analyzed for dioxin concentration, and the calculated dioxin removal efficiency was 90.5%.

According to the GB/T 5453-1997 test standard, the air permeability test was performed on the combination of conventional PTFE filter bag + dioxin-free bag cage under a pressure difference of 200Pa, and the air permeability was 7.7m ³ /m ² /min.

Example 2

After mixing 9.9kg of dioxin-removing catalyst powder, 3.2kg of polytetrafluoroethylene powder, 0.5kg of monoalkoxy titanate, and 0.75kg of nano-silicon dioxide, they are placed on a planetary ball mill for ball milling at a speed of 220r /min, every 20min is a round, and there are 5 rounds of grinding, that is, the ball milling time is 100min. Then melt processing at 380°C to obtain material A, then add 0.075kg dioctyl phthalate to material A, obtain material B after stirring, and then extrude powder particles with an average particle size of 25 μm through a granulator, Obtain printing materials that can be used by 3D printing equipment; use Solidworks software to create a 3D model of the bag cage. The size of the substrate is: the diameter of the upper ring is 145mm, the thickness is 5mm, the diameter of the bottom is 110mm, the length of the bag cage is 970mm, and the diameter of the micropore is 2mm. Microhole spacing 5mm. Use Simplify 3D software to slice the created dioxin-free bag cage 3D model, set the layer height to 0.2mm, and the wall thickness to 0.1mm; 3D printing adopts selective thermal sintering technology, firstly, the prepared powder is passed through powder coating The rollers are evenly laid on the operation table, and the operation table is preheated to 260°C at the same time, and then the printing head moving speed is set to 2500mm/min and the power is 30W, and the 3D printing is carried out according to the modeling; after the printing is completed, it is shaped at 100°C and cooled Finally, the unsintered excess powder is removed, and finally the de-dioxin bag cage is obtained.

The obtained catalytic oxidation filter material was used to evaluate the performance of dioxin removal on the SCR dioxin removal test bench using simulated flue gas. . The flue gas at the inlet and outlet of the reactor was collected and analyzed for dioxin concentration, and the removal efficiency of dioxin was calculated to be 95%.

According to the GB/T 5453-1997 test standard, the air permeability test was carried out on the combination of conventional PTFE filter bag + dioxin-free bag cage under a pressure difference of 200Pa, and the air permeability was 8.2m ³ /m ² /min.

Example 3

Mix 9.9kg of dioxin-removing catalyst powder, 3.2kg of polytetrafluoroethylene powder, 0.5kg of monoalkoxy titanate, and 0.75kg of nano-silicon dioxide and place them on a planetary ball mill for ball milling. The speed of the ball mill is 250r/ min, every 20min is a round, and there are 6 rounds of grinding, that is, the ball milling time is 120min. Then melt processing at 400°C to obtain material A, then add 0.075kg of dioctyl phthalate to the material A, stir to obtain material B, and then extrude powder particles with an average particle size of 30 μm through a granulator, Obtain printing materials that can be used by 3D printing equipment; use Solidworks software to create a 3D model of the bag cage. The size of the substrate is: the diameter of the upper ring is 145mm, the thickness is 5mm, the diameter of the bottom is 110mm, the length of the bag cage is 970mm, and the diameter of the micropore is 5mm. Microhole spacing 5mm. Use Simplify 3D software to slice the created dioxin-free bag cage 3D model, set the layer height to 0.2mm, and the wall thickness to 0.3mm; 3D printing adopts selective thermal sintering technology. The rollers are evenly laid on the operation table, and the operation table is preheated to 260°C at the same time, and then the printing head moving speed is set to 1800mm/min and the power is 25W, and the 3D printing is carried out according to the modeling; after the printing is completed, it is shaped at 100°C and cooled Finally, the unsintered excess powder is removed, and finally the de-dioxin bag cage is obtained.

The obtained catalytic oxidation filter material was used to evaluate the performance of dioxin removal on the SCR dioxin removal test bench using simulated flue gas. . The flue gas at the inlet and outlet of the reactor was collected and analyzed for dioxin concentration, and the calculated dioxin removal efficiency was 97%.

According to the GB/T 5453-1997 test standard, the air permeability test was carried out on the combination of conventional PTFE filter bag + dioxin-free bag cage under a pressure difference of 200Pa, and the air permeability was 8.3m ³ /m ² /min.

Example 4

Mix 9.9kg of dioxin-removing catalyst powder, 3.2kg of polytetrafluoroethylene powder, 0.5kg of monoalkoxy titanate, and 0.75kg of nano-silicon dioxide and place them on a planetary ball mill for ball milling. The speed of the ball mill is 250r/ min, every 20min is a round, and there are 6 rounds of grinding, that is, the ball milling time is 120min. Then melt processing at 400°C to obtain material A, then add 0.075kg dioctyl phthalate to material A, obtain material B after stirring, and then extrude powder particles with an average particle size of 40 μm through a granulator, Obtain printing materials that can be used by 3D printing equipment; use Solidworks software to create a 3D model of the bag cage. The size of the substrate is: the diameter of the upper ring is 145mm, the thickness is 5mm, the diameter of the bottom is 110mm, the length of the bag cage is 970mm, and the diameter of the micropore is 10mm. Microhole spacing 15mm. Use Simplify 3D software to slice the created dioxin-free bag cage 3D model, set the layer height to 0.6mm, and the wall thickness to 0.3mm; 3D printing adopts selective thermal sintering technology. The rollers are evenly laid on the operation table, and the operation table is preheated to 260°C at the same time, and then the printing head moving speed is set to 1800mm/min and the power is 20W, and the 3D printing is carried out according to the modeling; after the printing is completed, it is shaped at 100°C and cooled Finally, the unsintered excess powder is removed, and finally the de-dioxin bag cage is obtained.

The obtained catalytic oxidation filter material was used to evaluate the performance of dioxin removal on the SCR dioxin removal test bench using simulated flue gas. . The flue gas at the inlet and outlet of the reactor was collected and analyzed for dioxin concentration, and the calculated dioxin removal efficiency was 92%.

According to the GB/T 5453-1997 test standard, the air permeability test was carried out on the combination of conventional PTFE filter bag + dioxin-free bag cage under a pressure difference of 200Pa, and the air permeability was 10.1m ³ /m ² /min.

Example 5

Mix 9.2kg of dioxin-removing catalyst powder, 3.8kg of polytetrafluoroethylene powder, 0.45kg of monoalkoxy titanate, and 0.65kg of nano-silicon dioxide and place them on a planetary ball mill for ball milling. The speed of the ball mill is 250r/ min, every 20min is a round, and there are 6 rounds of grinding, that is, the ball milling time is 120min. Then melt processing at 380°C to obtain material A, then add 0.055 kg of dioctyl phthalate to the material A, stir to obtain material B, and then extrude powder particles with an average particle size of 60 μm through a granulator, Obtain printing materials that can be used by 3D printing equipment; use Solidworks software to create a 3D model of the bag cage. The size of the substrate is: the diameter of the upper ring is 145mm, the thickness is 5mm, the diameter of the bottom is 110mm, the length of the bag cage is 970mm, and the diameter of the micropore is 10mm. Microhole spacing 15mm. Use Simplify 3D software to slice the created dioxin-free bag cage 3D model, set the layer height to 0.8mm, and the wall thickness to 0.3mm; 3D printing adopts selective thermal sintering technology. Spread the rollers evenly on the operating table, preheat the operating table to 260°C, then set the printing head moving speed to 1500mm/min and the power to 10W, and then carry out 3D printing according to the modeling; after printing, set the shape at 100°C and cool down Finally, the unsintered excess powder is removed, and finally the de-dioxin bag cage is obtained.

The obtained catalytic oxidation filter material was used to evaluate the performance of dioxin removal on the SCR dioxin removal test bench using simulated flue gas. . The flue gas at the inlet and outlet of the reactor was collected and analyzed for dioxin concentration. The calculated dioxin removal efficiency was 94%.

According to the GB/T 5453-1997 test standard, the air permeability test was carried out on the combination of conventional PTFE filter bag + dioxin-free bag cage under a pressure difference of 200Pa, and the air permeability was 10m ³ /m ² /min.

Example 6

After mixing 10.5kg of dioxin-removing catalyst powder, 4.6kg of polytetrafluoroethylene powder, 1.05kg of monoalkoxy titanate, and 1.6kg of nano-silicon dioxide, they are placed on a planetary ball mill for ball milling, and the ball mill speed is 250r/ min, every 20min is a round, and there are 6 rounds of grinding, that is, the ball milling time is 120min. Then melt processing at 400°C to obtain material A, then add 0.53kg of dioctyl phthalate to the material A, stir to obtain material B, and then extrude powder particles with an average particle size of 40 μm through a granulator, Obtain printing materials that can be used by 3D printing equipment; use Solidworks software to create a 3D model of the bag cage. The size of the substrate is: the diameter of the upper ring is 145mm, the thickness is 5mm, the diameter of the bottom is 110mm, the length of the bag cage is 970mm, and the diameter of the micropore is 8mm. Microhole spacing 4mm. Use Simplify 3D software to slice the created dioxin-free bag cage 3D model, set the layer height to 0.6mm, and the wall thickness to 0.3mm; 3D printing adopts selective thermal sintering technology. The rollers are evenly laid on the operation table, and the operation table is preheated to 260°C at the same time, and then the printing head moving speed is set to 1000mm/min and the power is 5W, and the 3D printing is carried out according to the modeling; after the printing is completed, it is shaped at 100°C and cooled Finally, the unsintered excess powder is removed, and finally the de-dioxin bag cage is obtained.

The obtained catalytic oxidation filter material was used to evaluate the performance of dioxin removal on the SCR dioxin removal test bench using simulated flue gas. . The flue gas at the inlet and outlet of the reactor was collected and analyzed for dioxin concentration, and the removal efficiency of dioxin was calculated to be 90%.

According to the GB/T 5453-1997 test standard, the air permeability test was carried out on the combination of conventional PTFE filter bag + dioxin-free bag cage under a pressure difference of 200Pa, and the air permeability was 9.6m ³ /m ² /min.

Example 7

Mix 8.1kg of dioxin-removing catalyst powder, 2.0kg of polytetrafluoroethylene powder, 0.13kg of monoalkoxy titanate, and 0.53kg of nano-silicon dioxide and place them on a planetary ball mill for ball milling. The speed of the ball mill is 250r/ min, every 20min is a round, and there are 6 rounds of grinding, that is, the ball milling time is 120min. Then melt processing at 400°C to obtain material A, then add 0.026kg dioctyl phthalate to material A, obtain material B after stirring, and then extrude powder particles with an average particle size of 20 μm through a granulator, Obtain printing materials that can be used by 3D printing equipment; use Solidworks software to create a 3D model of the bag cage. The size of the substrate is: the diameter of the upper ring is 145mm, the thickness is 5mm, the diameter of the bottom is 110mm, the length of the bag cage is 970mm, and the diameter of the micropore is 4mm. Microhole spacing 8mm. Use Simplify 3D software to slice the created dioxin-free bag cage 3D model, set the layer height to 0.2mm, and the wall thickness to 0.3mm; 3D printing adopts selective thermal sintering technology. The rollers are evenly laid on the operation table, and the operation table is preheated to 260°C at the same time, and then the printing head moving speed is set to 4000mm/min and the power is 25W, and the 3D printing is carried out according to the modeling; after the printing is completed, it is shaped at 100°C and cooled Finally, the unsintered excess powder is removed, and finally the de-dioxin bag cage is obtained.

The obtained catalytic oxidation filter material was used to evaluate the performance of dioxin removal on the SCR dioxin removal test bench using simulated flue gas. . The flue gas at the inlet and outlet of the reactor was collected and analyzed for dioxin concentration, and the calculated dioxin removal efficiency was 91%.

According to the GB/T 5453-1997 test standard, the air permeability test was carried out on the combination of conventional PTFE filter bag + dioxin-free bag cage under a pressure difference of 200Pa, and the air permeability was 9.5m ³ /m ² /min.

At present, the dioxin-removing catalytic filter bag prepared by the impregnation method is tested according to the standard in the above examples, and the air permeability is 4.5-7.7m ³ /m ² /min, which is lower than the 7.7-10.1m ³ /m ² /min of the present invention. min. Since the air permeability is directly proportional to the resistance, it proves that the combination of conventional filter bag + dioxin-free bag cage has lower resistance than the combination of dioxin-free filter bag + conventional bag cage. At the same time, due to the use of 3D printing technology for molding, products with different structures and parameters can be conveniently manufactured by changing the model settings. The product has a high degree of freedom and strong diversity. Due to the use of automatic control, the product quality is stable and reliable, and it is suitable for engineering promotion.

Claims (8)

1. A preparation method of a selective thermal sintering molded 3D printed dioxin removal bag cage is characterized by comprising the following steps:

(1) Mixing 55 to 80 parts by weight of dioxin-free catalyst powder, 15 to 35 parts by weight of polytetrafluoroethylene powder, 1~8 parts by weight of monoalkoxy titanate and 4 to 12 parts by weight of nano silicon dioxide, carrying out ball milling, carrying out melt processing to obtain a material A, adding 0.2 to 4 parts by weight of dioctyl phthalate into the material A, stirring, and carrying out extrusion granulation to obtain a printing material for 3D printing;

(2) Creating a three-dimensional model of a dioxin removal bag cage, wherein the main body of the dioxin removal bag cage is a straight cylinder provided with micropores, the bottom of the straight cylinder is a cage bottom, the cage bottom is provided with micropores, and the diameters and the distances of the micropores are set at the same time;

(3) Slicing the dioxin-removing bag cage three-dimensional model created in the step (2), and setting the layer height and the wall thickness to obtain a dioxin bag cage three-dimensional model capable of being printed;

(4) 3D printing adopts a selective thermal sintering method, firstly, uniformly paving an operation table on prepared powder through a powder paving roller, simultaneously preheating the operation table, then setting the moving speed and power of a printing head, and performing 3D printing on the basis of the printable dioxin bag cage three-dimensional model obtained in the step (3);

(5) Cooling and shaping are carried out after printing is finished, and unsintered powder is removed after cooling and shaping, so that the dioxin-removing bag cage is finally obtained; in the step (1), manganese nitrate, cerous nitrate hexahydrate and cobalt sulfate heptahydrate in a mass ratio of 1.5:2.1:1, adding the solution into deionized water, stirring to form a solution, dropwise adding ammonia water into the solution to control the pH value to be 8.2 until precipitation is completed, sequentially filtering and drying to obtain precursor powder, roasting the precursor powder in air at 400 ℃ for 4 hours, grinding and sieving to prepare particles of 1200 meshes to obtain the dioxin-removed powder catalytic powder;

the diameter of each micropore in the dioxin removal bag cage three-dimensional model in the step (2) is 2-10mm, and the distance between micropores is 4-15mm.

2. The method for preparing the selectively hot-sintered 3D-printed dioxin-removal bag cage according to the claim 1, wherein the particle size of the polytetrafluoroethylene powder in the step (1) is 500nm to 50 μm.

3. The method for preparing the selectively hot-sintered 3D printed dioxin-removal bag cage according to the claim 1, wherein the grain size of the 3D printed material in the step (1) is 25 to 100 μm.

4. The method for preparing the selectively hot-sintered molded 3D printed dioxin-removal bag cage according to the claim 1, characterized in that the melting temperature in the step (1) is 380 to 400 ℃.

5. The method for preparing the selectively hot-sintered 3D printed dioxin-removal bag cage according to the claim 1, wherein in the step (3), the layer height is 0.2 to 1mm, the wall thickness is 0.1 to 0.3mm, the diameter of each micropore is 2 to 10mm, and the distance between micropores is 4 to 15mm.

6. The method for preparing the selective thermal sintering molded 3D printed dioxin-removing bag cage as claimed in the claim 1, wherein the moving speed of the printing head in the step (4) is 1000-4000mm/min, and the power is 5 to 30W.

7. A dioxin removal bag cage, characterized in that, prepared based on the method of any claim 1~6, the main body is a straight cylinder provided with micropores (2), the bottom of the straight cylinder is a cage bottom (4), the cage bottom (4) is provided with micropores (2), the diameter of the micropores is 2 to 10mm, and the distance (3) between the micropores is 4 to 15mm.

8. The dioxin-removing bag cage according to claim 7, wherein the top end of the straight cylinder is provided with a flanged upper ring opening (1).

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