KR102478940B1 - Method for manufacturing ptfe fiber and a ptfe membrane catalytic filter using the same - Google Patents

Abstract

Disclosed is a method for manufacturing a PTFE fiber for a PTFE membrane catalytic filter, wherein the processes of mixing, aging, compression, extrusion, rolling, sintering, oiling/stretching, and slitting are performed, a catalyst subjected to homogenization operation in the mixing process is introduced, the ratio of the introduced catalyst is 0.5 % or more and 0.6 % or less, and the ratio of an introduced lubricant is 28 % or more and 30 % or less.

Description

Method for manufacturing PTFE fiber and PTFE membrane catalyst filter using the same

The present invention relates to a method for manufacturing PTFE fibers and a PTFE membrane catalyst filter made using PTFE fibers, and more particularly, to a PTFE membrane catalyst with improved performance through an optimized mixing process in the step of manufacturing fibers. It relates to a method for producing PTFE fibers for filter production and a PTFE catalyst filter.

Against the background of the development of a catalytic filter that simultaneously reduces dust and NOx contained in exhaust gas, the emission standards for harmful gases in exhaust gas are gradually being strengthened. High-performance material development and process improvement are showing high interest, but domestic technology is insufficient, and core technology relies on advanced overseas technology.

In particular, due to economic and spatial problems of small operators such as small and medium-sized incineration facilities, methods such as a combination of a plurality of unit facilities are causing practical problems such as installation space and investment costs.

Due to these conditions, large-scale facilities such as SCR and SNCR are currently being operated as a nitrogen oxide (NOx) removal process in Korea.

Republic of Korea Patent Publication No. 10-2009-0102835 "Felt for filter of film divided into microfibers and manufacturing method thereof" Republic of Korea Patent Registration No. 10-1385115 "Dust filter with high-performance dust removal device and method of operation thereof" Korean Patent Registration No. 10-1700982 "Method for manufacturing a stretched polytetrafluoroethylene porous film or tape carrying catalyst particles and a filter for removing ozone" Republic of Korea Patent Registration No. 10-1734097 "Method of manufacturing filter material for high-density hybrid filter bag for dust collector"

The present invention is to provide a method for manufacturing a PTFE membrane catalytic filter for reducing fine dust and NOx contained in exhaust gas so that it can be applied to dust collection facilities operated by existing small and medium incineration facilities to satisfy improved emission standards. do.

Further, the present invention aims to provide a method for producing a catalyst fiber for producing a PTFE membrane catalytic filter.

In addition, the present invention aims to provide optimized catalyst fiber manufacturing process conditions.

In order to solve the above problems, the present invention is a powder mixing method for preparing PTFE fibers by mixing a De-NOx catalyst and a lubricant with PTFE powder, in a mixer for mixing the powder by repeating falling using gravity and centrifugal force. Disclosed is a powder mixing method for producing PTFE fibers, characterized in that a lubricant is sprayed on the powders in the process of adding and rotating De-NOx catalyst powder to create a mixed powder.

According to one embodiment of the present invention, the lubricant is disclosed a powder mixing method for producing PTFE fibers characterized in that the lubricant is adjusted so that it is sprayed only on the PTFE powder and the De-NOx catalyst powder without spraying on the wall surface of the mixer.

According to one embodiment of the present invention, the De-NOx catalyst powder discloses a powder mixing method for producing PTFE fibers, characterized in that 0.5% by weight or more and 0.7% by weight of the total weight.

According to one embodiment of the present invention, the lubricant discloses a powder mixing method for producing PTFE fibers, characterized in that 27% by weight or more and 29% by weight or less of the total weight.

According to one embodiment of the present invention, the injection rate of the lubricant is disclosed a powder mixing method for producing PTFE fibers, characterized in that 150g / min or more and less than 250g / min.

According to one embodiment of the present invention, the rotational speed of the mixer is 10 rpm or more and 14 rpm or less, and the mixing time is 40 minutes or more and 70 minutes or less.

In addition, the present invention is a method for manufacturing a PTFE fiber for manufacturing a PTFE membrane catalyst filter manufactured through a mixing process, an aging process, a compression process, an extrusion process, a rolling process, a sintering process, an oil making/stretching process, and a slitting process, wherein the mixing process comprises PTFE fiber manufacturing characterized by creating mixed powder by spraying a lubricant to the powder in the process of putting PTFE powder and De-NOx catalyst powder in a mixer that mixes the powder by repeated falling using gravity and centrifugal force and rotating it start the way

According to one embodiment of the present invention, the lubricant is disclosed a method for manufacturing a PTFE fiber, characterized in that the lubricant is adjusted so that it is sprayed only on the PTFE powder and the De-NOx catalyst powder without being sprayed on the wall surface of the mixer.

According to one embodiment of the present invention, the De-NOx catalyst powder discloses a method for producing a PTFE fiber, characterized in that 0.5% by weight or more and 0.7% by weight of the total weight.

According to one embodiment of the present invention, the lubricant discloses a method for manufacturing a PTFE fiber, characterized in that 27% by weight or more and 29% by weight or less of the total weight.

According to one embodiment of the present invention, the injection rate of the lubricant is disclosed a PTFE fiber manufacturing method characterized in that 150g / min or more and less than 250g / min.

According to one embodiment of the present invention, the rotational speed of the mixer is 10 rpm or more and 14 rpm or less, and the mixing time is 40 minutes or more and 70 minutes or less.

In addition, the present invention is a method for manufacturing a PTFE membrane catalyst filter using a PTFE fiber manufactured through a mixing process, an aging process, a compression process, an extrusion process, a rolling process, a sintering process, an oil making/stretching process, and a slitting process, wherein the mixing In the process, the PTFE powder and the De-NOx catalyst powder are put into a mixer that mixes the powder by repeated falling using gravity and centrifugal force, and in the process of rotating the powder, a lubricant is sprayed to the powder to create a mixed powder. A method for manufacturing a membrane catalytic filter is disclosed.

According to one embodiment of the present invention, a method for manufacturing a PTFE membrane catalyst filter is disclosed, wherein the lubricant is controlled to be sprayed only on the PTFE powder and the De-NOx catalyst powder without being sprayed on the wall surface of the mixer.

According to one embodiment of the present invention, the De-NOx catalyst powder discloses a method for manufacturing a PTFE membrane catalyst filter, characterized in that 0.5% by weight or more and 0.7% by weight of the total weight.

According to one embodiment of the present invention, the lubricant is disclosed a method for manufacturing a PTFE membrane catalyst filter, characterized in that 27% by weight or more and 29% by weight or less of the total weight.

According to one embodiment of the present invention, a method for manufacturing a PTFE membrane catalyst filter is disclosed, wherein the injection rate of the lubricant is 150 g/min or more and less than 250 g/min.

According to one embodiment of the present invention, the rotational speed of the mixer is 10 rpm or more and 14 rpm or less, and the mixing time is 40 minutes or more and 70 minutes or less.

In addition, the present invention discloses a PTFE fiber manufactured by the method for manufacturing a PTFE fiber described in the above embodiment.

In addition, the present invention discloses a PTFE membrane catalyst filter manufactured by the method for manufacturing a PTFE membrane catalyst filter described in the above embodiment.

According to the present invention, it is possible to remove NOx and dust at the same time by applying a PTFE membrane to filter dust in exhaust gas from the filter surface and to remove nitrogen oxides by reacting NOx in a bag filter carrying a catalyst.

In addition, according to the present invention, the catalytic filter, which is dependent on overseas technology and products, is a catalytic filter having NOx reduction function in the bag filter, which is the final product, by imparting a catalytic function through a mixing method from the step of manufacturing a fiber rather than a coating method. It becomes possible to manufacture

1 is a photograph of a mixing step in the process of manufacturing fibers in the present invention.
2 is a photograph of a maturation step in the process of manufacturing fibers in the present invention.
3 is a photograph of a compression step in the process of manufacturing fibers in the present invention.
4 is a photograph of an extrusion step in the process of manufacturing fibers in the present invention.
5 is a photograph of a rolling step in the process of manufacturing fibers in the present invention.
6 is a photograph of a sintering step in the process of manufacturing fibers in the present invention.
7 is a photograph of a deoiling/stretching step in the process of manufacturing fibers in the present invention.
8 is a photograph of a slitting step in the process of manufacturing fibers in the present invention.
Fig. 9 is a photograph of the reticulated catalyst fibers spread after slitting.
10 is a photograph of a catalyst fiber wound on a bobbin.
11A is a photograph showing a billet of Sample 1.
11B is a photograph showing a rolled sheet of Sample 1.
12A is a photograph showing a billet of Sample 2.
12B is a photograph showing a rolled sheet of Sample 2.
13A is a photograph showing a billet of Sample 3.
13B is a photograph showing a rolled sheet of Sample 3.
14A is a photograph showing a billet of Sample 4.
14B is a photograph showing a rolled sheet of Sample 4.
15 is a photograph showing desorption of the catalyst during the slitting process of Sample 7.
16 is a photograph showing desorption of the catalyst during the slitting process of Sample 8.
17A is a photograph showing a billet of Sample 9.
17B is a photograph showing a rolled sheet of Sample 9.
18 is a photograph showing the billet of Sample 10.

Hereinafter, the present invention will be described in more detail with reference to the drawings. In this specification, the same or similar reference numerals are given to the same or similar components even in different embodiments, and the description is replaced with the first description. Singular expressions used herein include plural expressions unless the context clearly dictates otherwise.

In addition, in the description with reference to the accompanying drawings, the same reference numerals are given to the same components regardless of reference numerals, and overlapping descriptions thereof will be omitted. In describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted.

Referring to Figures 1 to 8, the general PTFE Fiber manufacturing process is performed in the order of mixing, aging, compression, extrusion, rolling, sintering, oil production, stretching, and slitting processes.

In the catalyst fiber manufacturing process for manufacturing a PTFE membrane catalyst filter according to the present invention, PTFE powder and lubricant are mixed in a mixer at a certain ratio in the mixing process. so you have to mix it.

At this time, due to the De-NOx catalyst for imparting a catalytic function, the ratio of raw materials is different in the manufacture of catalyst fibers, and as a result, workability (continuous operation) and productivity (loss rate) depend on temperature, speed, and working time in each process. , a difference occurs in the De-NOx effect (nitrogen oxide removal function).

Since these various conditions are related to the manufacture of catalytic filters, research on these conditions is necessary in order to most efficiently produce products of the highest quality.

In addition, according to the revised regulations as shown in Table 1 below, the dust/nitrogen oxide emission standards have become stricter.

Current emission standards Revised emission standards reinforcement rate dust 10-70 mg/Sm ³ 5-50 mg/Sm ³ 33% Nitrogen Oxides (NOx) 20 to 530 ppm 10 to 250 ppm 28% Emission standards for facilities with an incineration capacity of 2 tons or more Dust: 10 mg/Sm ³
NOx : 50ppm

This content describes the optimal working conditions in the mixing process of the fiber manufacturing process used in the manufacture of PTFE membrane filters to satisfy these conditions.

PTFE powder and De-NOx catalyst are mixed with liquid lubricant in a mixer in the form of powder. If the ratio of lubricant is low, problems occur when forming billets in the extrusion process, and if the ratio of lubricant is high, oil removal is not good. Otherwise, the loss rate increases.

When these are mixed in an appropriate ratio, problems in workability and productivity can be reduced in the post-process.

In addition, if the ratio of the De-NOx catalyst added to impart the catalytic function is low, the De-NOx effect of the catalyst fiber is low, which may cause compatibility problems. Workability and productivity are low, and the amount of desorption of the catalyst caught on the needle during slitting is large, resulting in the final deterioration of the De-NOx effect.

Therefore, while the proper mixing ratio of PTFE powder, De-NOx catalyst, and lubricant is important when manufacturing catalyst fibers, additional detailed working conditions are also required in the mixing process.

In addition, the mixer uses gravity and centrifugal force to repeatedly fall and mix, but when mixing at too high a speed, the agglomeration of the PTFE powder occurs and the De-NOx catalyst cannot be properly mixed.

Since PTFE powder and De-NOx catalyst do not melt even at high temperatures and are physically stabilized, they have physical properties that cannot be chemically/physically bonded to each other, so the role of lubricant in the mixing process is quite important.

Since uniform mixing is impossible by simply putting lubricants together in a mixer and mixing them, how the lubricants are mixed in the mixing process is also a very important factor.

The lubricant is evenly sprayed and mixed into the two powder mixtures (PTFE, De-NOx catalyst) through the inlet of the rotating mixer. If the amount of injection is large, the lubricant may clump together in a part and may not be mixed evenly.

Lubricant should be sprayed only on the two powder mixtures, and controlled so that it is not sprayed on the mixer wall. When spraying on the wall of the mixer, the two powder mixtures stick to the wall of the mixer and do not fall, resulting in loss and uneven mixing.

As the content of the De-NOx catalyst increases, the De-NOx effect increases. In the mixing process, as the amount of the De-NOx catalyst increases, the amount of lubricant must be increased and the mixing time must be increased to improve the dispersibility, workability, and productivity of the catalyst. It can be.

Reflecting these conditions, the experiment was conducted as follows.

The conditions applied to the experiment were as follows.

In the present invention, sintering is performed within a temperature range of 300° C. to 500° C., and specifically, it is preferable that sintering is performed at around 400° C. However, in the present invention, emphasis is placed on the ratio of the catalyst used in the mixing process, the ratio of the lubricant, the lubricant injection speed, the mixing speed, and the mixing time rather than the sintering temperature conditions.

Whether or not the homogenization operation was successful is judged based on the degree of mixing of the lubricant, PTFE, and catalyst. According to an embodiment of the present invention, the specific determination of the degree of mixing is made by checking the mixing ratio or color of the mixed powder.

In the present invention, the homogenization grade is classified by dividing into mixing ratio analysis evaluation and operator evaluation. More specifically, a score is given to the result of analysis of the mixing ratio of the sample, and the evaluation score of the workers is averaged to classify the grade into 'excellent', 'good', and 'unsatisfactory'.

This is to compensate for the change in the mixing ratio due to vibration in the process of taking samples for mixing ratio analysis.

The mixing ratio analysis of the sample is performed as follows.

When the mixing ratio of the sample is analyzed, if the mixing ratio is 80% or more, the homogenization grade is evaluated as 'excellent'. If the mixing ratio is 50% or more and less than 80%, the homogenization grade is evaluated as 'good'. If the mixing ratio is less than 50%, the homogenization grade is evaluated as 'insufficient'.

If the homogenization grade is 'excellent', 3 points are given. If the homogenization grade is 'good', 2 points are given. If the homogenization grade is 'sufficient', 1 point is given.

Operator evaluation of the sample is made as follows.

First, 20 workers involved in product production are selected for worker evaluation.

After that, the selected workers are shown the mixed powder before sampling.

Each worker gives 3 points if the mixture of the mixed powder is judged to be excellent, 2 points if the mixture is judged to be good, and 1 point if the mixture is judged to be insufficient. The scores given by each worker are averaged to classify the homogenization grade of the mixed powder.

For consistent evaluation, the following criteria were presented to the workers.

First, the workers are shown samples with 90%, 60%, and 30% mixing ratios.

In addition, if the mixing ratio is determined to be 80% or more in the operator's judgment and the clumped area is not visible when looking at the color of the powder, 3 points are given. If the mixing ratio is judged to be 50% or more and less than 80%, and 1 or 2 clumped areas are visible when looking at the color of the powder, 2 points are given. When the mixing ratio is judged to be less than 50% and the color of the powder is seen, 1 point is given if three or more areas where they are clumped together are visible.

In worker evaluation, 3 points means 'excellent', 2 points means 'good', and 1 point means 'insufficient'.

Calculate the final evaluation score by averaging the score calculated through mixing ratio analysis and the average score of workers calculated through worker evaluation.

The final evaluation score is rounded off to determine that 3 points are 'excellent' in the homogenization grade, 2 points are 'good' in the homogenization grade, and 1 point are 'poor' in the homogenization grade.

It is determined that the factors that have the greatest influence on the homogenization grade are the mixing speed (rpm) and the mixing time (min).

Therefore, in order to determine how to adjust the mixing speed and mixing time conditions, the homogenization grade was determined by varying the mixing time and mixing speed as shown in Table 2 below.

Table 3 is a table showing the homogenization grade evaluation criteria in the present invention.

mixing speed mixing time homogenization grade 20rpm 30min Inadequate 20rpm 60min Inadequate 18rpm 60min Good 16rpm 60min Great 14 rpm 60min Great 14 rpm 50min Great 14 rpm 40min Good 14 rpm 30min Inadequate

According to Table 2, when the mixing speed was 20 rpm, it could be confirmed that the homogenization grade was 'insufficient' regardless of the mixing time.

When the mixing speed was lowered to 18 rpm and the mixing time was 60 min, the homogenization grade was confirmed as 'good'.

When the mixing speed was lowered to 16 rpm and the mixing time was 60 min, the homogenization grade was confirmed as 'excellent'.

When the mixing speed was lowered to 14 rpm, the homogenization grade was confirmed as 'excellent' when the mixing time was 60 min to 50 min.

When the mixing speed was 14 rpm and the mixing time was 40 min, the homogenization grade was confirmed as 'good'.

However, when the mixing speed was 14 rpm and the mixing time was reduced to 30 min, it was confirmed that the homogenization grade was 'insufficient'.

That is, the homogenization grade tends to increase as the mixing speed decreases, but when the mixing time is lowered to 30 min or less, it can be seen that the homogenization grade decreases even if the mixing speed decreases.

Since the performance of the catalyst fiber is improved when the homogenization grade of the powder is high, the mixing speed is set to 20 rpm or less and the mixing time is set to 60 min in the catalyst fiber (or PTFE membrane filter using the same) experiment.

PTFE membrane catalyst filter experiments were performed based on catalyst desorption rate, workability, productivity, De-NOx efficiency, and catalyst dispersibility.

The catalyst desorption rate was measured in the range of 20% to 50%. When measuring the result value, if the catalyst desorption rate exceeds 50%, it is meaningless to measure an accurate value because the desorption rate is excessive and commercialization is difficult. Therefore, if the catalyst desorption rate exceeds 50%, it is expressed as 50%. Likewise, if the catalyst desorption rate is 20% or less, it is meaningless to measure an accurate value because it is sufficient for commercialization. Therefore, when the catalyst desorption rate was less than 20%, it was expressed as 20%.

Productivity was classified into 'excellent', 'good', and 'insufficient'.

In the present invention, the productivity grade is based on the frequency of error occurrence.

Errors that occur in the production process are judged based on whether the following three phenomena occur.

1) 'Cracking of the billet'

2) 'Hole on sheet'

3) 'Cracking of the rod'

If necessary, 'unstable thickness uniformity of sheet' and 'strength of sheet' may also be included in the criterion for error determination.

When evaluated according to the above criteria, productivity is evaluated as 'excellent' if no error occurs in the production process. Productivity is evaluated as 'good' when errors occur more than 0 and less than 2 times in the production process. If errors occur more than twice in the production process, productivity is evaluated as 'insufficient'.

If productivity is based on the number of defects in production, workability is based on the number of interruptions in the production process.

Specifically, workability is classified into 'excellent', 'good', and 'insufficient' based on the number of times the production process stops due to breakage in the slitting process.

In the workability evaluation, it is checked how many times breakage occurs when working with a total of 10 kg of PTFE mixed powder. It is calculated that workability decreases by 5% for each breakage.

Table 3 is a table summarizing workability evaluation criteria of the present invention.

number of cuts Workability % Workability evaluation less than 2 times over 90 Great More than 2 times and less than 5 times 75% or more and less than 90% Good more than 5 times less than 75% Inadequate

Referring to Table 3, when the workability is 90% or more (when the breakage occurs twice or less), the workability is evaluated as 'excellent'.

Workability is evaluated as 'good' when workability is less than 90% and 75% or more (when breakage occurs more than 2 times and less than 5 times).

When workability is less than 75% (when breakage occurs more than 5 times), workability is evaluated as 'insufficient'.

If the workability is evaluated as 'insufficient', it is necessary to change the conditions because it is impossible to proceed with the process any further.

The dispersibility of the catalyst indicates whether the catalyst is evenly distributed on the surface of the nonwoven fabric when the nonwoven fabric is produced using the PTFE fiber prepared according to the present invention.

Dispersion evaluation is made by observing five random spots on the nonwoven fabric sample with an optical microscope.

As a result of observing the above five random spots, when the aggregation of the catalyst is observed less than 3 times, the dispersibility is evaluated as 'excellent'.

As a result of observing the five random spots, when the aggregation of the catalyst is observed 3 or more times and less than 6 times, the dispersibility is evaluated as 'good'.

As a result of observing the above 5 random spots, when aggregation of the catalyst is observed 6 or more times, the dispersibility is evaluated as 'insufficient'.

De-NOx filtration efficiency was measured based on the Modified BS EN 1822-3 test method.

The filter fiber has a filtration efficiency of 99.9% or more for 0.3 ㎛ particles at 32LPM, and the pressure loss at this time is less than 100 mmAq. The final catalyst filter manufactured by making a non-woven fabric with these catalyst fibers and compounding the PTFE membrane has an air permeability of 3 cm 3 / cm 2.s or more.

If the De-NOx efficiency is 7% or more, it is evaluated as 'excellent'.

If the De-NOx efficiency is 3% or more and less than 5%, it is evaluated as 'normal'.

If the De-NOx efficiency is less than 3%, it is evaluated as 'bad'.

According to the criteria described above, the experimental results are shown in Table 4 below.

division
mixing process
catalyst ratio
(weight%) slush
ratio
(weight%) lubricant dispensing speed
(g/min) mixing speed
(rpm) mix
time
(min) Catalytic Fiber Results note catalyst
dropout rate Workability productivity De-NOx
efficiency catalyst
dispersibility #One 0.3 25 250 20 30
50% Inadequate under bad under poor catalyst dispersibility;
Frequent breakage during slitting #2 0.3 25 250 20 60 45% Inadequate under bad middle Catalyst dispersibility Partially improved activity is very low #3 0.3 25 250 18 60 40% Good middle bad middle Catalyst dispersibility Partially improved activity is very low #4 0.3 25 250 16 60 40% Good middle bad middle no big change
very low activity #5 0.4 25 250 16 60 40% Good middle bad middle no big change
very low activity #6 0.4 25 250 14 60 40% Good middle bad award Partial improvement in catalyst dispersibility
very low activity #7 0.5 26 250 14 60 30% Good award commonly middle Sheet hole occurrence
low activity #8 0.5 28 200 12 30 20% Good middle commonly under heterogeneity of the catalyst
low activity #9 0.5 28 250 12 60 20% Inadequate middle commonly middle Poor workability
(More than billet and rod) #10 0.5 28 200 12 60 20% Great award Great award Excellent overall
#11 0.5 28 220 13 60 20% Good award Great award Excellent overall
#12 0.6 29 180 13 60 20% Good award Great award Excellent overall
#13 0.7 28 200 12 60 30% Inadequate under commonly under Increased desorption rate of catalyst
Increased frequency of disconnections #14 0.7 29 200 16 60 25% Inadequate under Great middle Excellent denitrification performance
Frequent break-ups #15 0.7 30 200 8 60 20% Good middle Great middle Excellent denitrification performance
low productivity #16 0.5 28 270 12 60 20% Inadequate under bad under poor dispersibility
Low workability and productivity #17 0.5 28 130 12 60 20% Good middle bad under Confirmation of aggregation of catalyst
Holes and tears in the sheet due to clumped catalyst #18 0.5 25 200 12 60 25% Inadequate under bad under Sheet is hard
Difficult to control thickness #19 0.5 35 200 12 60 20% - under bad - Lubricant needs to be adjusted. Cannot be produced (fire risk)

Referring to Table 4 above, it can be seen how the characteristics of the PTFE catalyst fiber change by adjusting the catalyst ratio, homogenization degree (mixing speed and mixing time), lubricant ratio, and lubricant injection speed in the mixing process.

In the table above, if measurement is impossible because fiber production is impossible, '-' is marked.

In samples 1 to 3, the mixing process catalyst ratio was fixed at 0.3%, the lubricant ratio was 25%, and the lubricant injection speed was 250 g/min, and the mixing degree (homogenization grade) was varied.

Referring to Tables 2 and 4, in the case of Sample 1, the mixing speed was 20 rpm and the mixing time was 30 min. Under these conditions, the homogenization grade is identified as 'poor'.

In the case of sample 1, the catalyst desorption rate was 50%, the workability was 'sufficient', the productivity was 'low', the De-NOx efficiency was 'poor', and the catalyst dispersion was 'low'. According to this, it was confirmed that the catalyst dispersibility was poor and the activity of the catalyst (De-NOx efficiency) was very low, making it difficult to commercialize.

11A is a photograph showing a billet of Sample 1, and FIG. 11B is a photograph showing a rolled sheet of Sample 1.

Referring to FIGS. 11A and 11B , in the case of Sample 1, it can be seen that light streaks are formed in the billet due to aggregation of the catalyst. It seems that the catalyst is not evenly dispersed and clumped together. In addition, catalysts are aggregated in the form of thick dots in the sheet, and the desorption rate of the catalyst is high and disconnection occurs during fiber production.

In the case of Sample 2, the mixing speed was 20 rpm and the mixing time was 60 min. Under these conditions, the homogenization grade is identified as 'poor'.

In the case of sample 2, the catalyst desorption rate was 45%, workability 'sufficient', productivity 'low', De-NOx efficiency 'poor', and catalyst dispersibility 'medium'. Sample 2 had better catalyst desorption rate and catalyst dispersibility compared to sample 1, but it was confirmed that there was a problem in commercialization because the catalyst activity was still low.

12A is a photograph showing a billet of Sample 2, and FIG. 12B is a photograph showing a rolled sheet of Sample 2.

Referring to Figures 12a and 12b, as a result of the experiment by increasing the lubricant mixing time, it was confirmed that the aggregation and disconnection of the catalyst were partially improved, but the catalyst activity was low, making it difficult to commercialize.

For Sample 3, the mixing speed was 18 rpm and the mixing time was 60 min. Under these conditions, the homogenization grade is identified as 'good'.

In the case of sample 3, the catalyst desorption rate was 40%, workability 'good', productivity 'medium', De-NOx efficiency 'poor', and catalyst dispersibility 'medium'. Sample 3 had improved catalyst desorption rate, workability, and productivity compared to Sample 2, but it was confirmed that there was still a problem in commercialization due to low catalyst activity.

13A is a photograph showing a billet of Sample 3, and FIG. 13B is a photograph showing a rolled sheet of Sample 3.

Referring to this, when the catalyst homogenization grade is raised, it can be seen that the aggregation of the catalyst is improved compared to Samples 1 and 2. Through this, it can be seen that the homogenization of the catalyst affects the productivity.

For Sample 4, the mixing speed was 16 rpm and the mixing time was 60 min. Under these conditions, the homogenization grade is identified as 'good'.

In the case of sample 4, the catalyst desorption rate was 40%, workability 'good', productivity 'medium', De-NOx efficiency 'poor', and catalyst dispersibility 'medium'. It was confirmed that the results of Sample 4 were not significantly different from those of Sample 3. That is, it was confirmed that Sample 4 also had a problem in commercialization due to its low catalytic activity.

14A is a photograph showing a billet of Sample 4, and FIG. 14B is a photograph showing a rolled sheet of Sample 4. Referring to this, it can be seen that the aggregation of the catalyst between the billet and the sheet is further improved when the catalyst homogenization grade is raised by lowering the mixing speed.

In sample 5, other conditions were the same as in sample 4, and the mixing process catalyst ratio was improved by about 33% from 0.3% to 0.4%.

In the case of sample 5, the catalyst desorption rate was 40%, workability 'good', productivity 'medium', De-NOx efficiency 'poor', and catalyst dispersibility 'medium'. It was confirmed that the results of Sample 5 were not significantly different from those of Sample 4. That is, it was confirmed that Sample 5 still had a problem in commercialization due to its low catalytic activity.

In sample 6, other conditions were the same as in sample 5, and the mixing speed was lowered to 14 rpm.

In the case of sample 6, the catalyst desorption rate was 40%, workability 'good', productivity 'medium', De-NOx efficiency 'poor', and catalyst dispersibility 'good'. Although the catalyst dispersibility is improved in Sample 6, it is confirmed that there is no significant difference from Sample 5 in other results. Sample 4 was also confirmed to have problems in commercialization due to its low catalytic activity.

In Sample 7, the catalyst ratio and lubricant ratio were different from Sample 6. The catalyst ratio was increased from 0.4% to 0.5% and the lubricant ratio was increased from 25% to 26%.

Checking the results, in the case of sample 7, the catalyst desorption rate was 30%, workability 'good', productivity 'high', De-NOx efficiency 'normal', and catalyst dispersibility 'medium'. According to the results of sample 7, it can be seen that the catalyst activity has improved to a moderate level, but the activity is still insufficient for commercialization and the catalyst dispersibility has decreased. In addition, problems such as occurrence of holes in the sheet were confirmed.

In addition, referring to FIG. 15 , it can be confirmed that in Sample 7, a large amount of the catalyst is desorbed during the slitting process.

In sample 8, the experiment was conducted under conditions of catalyst ratio 0.5%, lubricant ratio 28%, lubricant injection speed 200g/min, mixing speed 12rpm, mixing time 30min.

Checking the results, in the case of sample 8, the catalyst desorption rate was 20%, workability 'good', productivity 'medium', De-NOx efficiency 'normal', and catalyst dispersibility 'low'. In the case of sample 8, the catalyst is unevenly distributed and the activity is low, so it is judged that it will be difficult to commercialize it.

Referring to FIG. 16 , it can be seen that the desorption of the catalyst in Sample 8 is greatly reduced compared to that in Sample 7.

In sample 9, the experiment was conducted by increasing the mixing time compared to sample 8. That is, in Sample 9, the catalyst ratio was 0.5%, the lubricant ratio was 28%, the lubricant injection speed was 250 g/min, the mixing speed was 12 rpm, and the mixing time was 60 min.

Checking the results, in the case of sample 9, the catalyst desorption rate was 20%, workability 'sufficient', productivity 'medium', De-NOx efficiency 'normal', and catalyst dispersibility 'medium'. In the case of sample 9, it was confirmed that product production was difficult due to poor workability. Specifically, it is confirmed that there is a problem in mass-producing the product due to a problem with the billet and the rod.

17A is a photograph showing a billet of Sample 9, and FIG. 17B is a photograph showing a rolled sheet of Sample 9.

Referring to FIGS. 17A and 17B , it was also confirmed that the billet was broken and that fine holes were formed in the process of sintering/stretching the sheet.

In Sample 10, the catalyst ratio was 0.5%, the lubricant ratio was 28%, the lubricant injection speed was 200g/min, the mixing speed was 12rpm, and the mixing time was 60min.

Checking the results, in the case of sample 10, the catalyst desorption rate was 20%, workability 'excellent', productivity 'high', De-NOx efficiency 'excellent', and catalyst dispersibility 'high'. As a result of the experiment, the characteristics to be measured were confirmed to be excellent overall, and it was confirmed that there was no problem in mass production of the product.

18 is a photograph showing the billet of Sample 10.

Referring to FIG. 18, as a result of the experiment by lowering the lubricant injection speed, it was confirmed that the cracking phenomenon in the billet was improved and the productivity was improved.

In Sample 11, the catalyst ratio was 0.5%, the lubricant ratio was 28%, the lubricant injection speed was 220 g/min, the mixing speed was 13 rpm, and the mixing time was 60 min.

Checking the results, in the case of sample 11, the catalyst desorption rate was 20%, workability 'good', productivity 'good', De-NOx efficiency 'excellent', and catalyst dispersibility 'good'. As a result of the experiment by slightly changing the lubricant injection speed and mixing speed in sample 10, sample 11 had slightly lower workability than sample 10, but it was judged as 'good' and it was confirmed that there was no problem in mass production of the product.

In Sample 12, the catalyst ratio was 0.6%, the lubricant ratio was 29%, the lubricant injection speed was 180 g/min, the mixing speed was 13 rpm, and the mixing time was 60 min.

Checking the results, in the case of sample 12, the catalyst desorption rate was 20%, workability 'good', productivity 'good', De-NOx efficiency 'excellent', and catalyst dispersibility 'good'. Sample 11 has somewhat lower workability than Sample 9, but it is judged to be a 'good' grade, and it is confirmed that there is no problem in mass production of the product.

That is, although all of Samples 10 to 12 are suitable for mass production, it can be confirmed that the conditions of Sample 10 are better than those of Samples 11 and 12.

In Sample 13, the catalyst ratio was increased while other conditions were fixed in Sample 10. That is, the conditions of sample 13 were catalyst ratio 0.7%, lubricant ratio 28%, lubricant injection speed 200g/min, mixing speed 12rpm, mixing time 60min.

Checking the results, in the case of sample 13, the catalyst desorption rate was 30%, workability 'sufficient', productivity 'low', De-NOx efficiency 'normal', and catalyst dispersibility 'low'. As a result of the experiment of Sample 13, it can be seen that when the catalyst ratio increases to 0.7% or more, the desorption rate of the catalyst increases and breaks occur several times during the fiber production process, resulting in problems in product production.

From the results of Sample 13, it was confirmed that the workability and productivity were very low, which may be because the ratio of the lubricant was fixed and only the ratio of the catalyst was increased. Also, since the powder was not mixed homogeneously, the lubricant ratio and mixing speed were changed in samples 14 and 15.

The conditions of sample 14 were catalyst ratio 0.7%, lubricant ratio 29%, lubricant injection speed 200g/min, mixing speed 16rpm, mixing time 60min.

Checking the results, in the case of sample 14, the catalyst desorption rate was 25%, workability 'sufficient', productivity 'low', De-NOx efficiency 'excellent', and catalyst dispersibility 'medium'. In the case of sample 14, it was confirmed that the denitrification performance was excellent, but the breakage frequency was high.

In Sample 15, the ratio of lubricant was increased and the mixing speed was decreased.

Specifically, the conditions of Sample 15 were a catalyst ratio of 0.7%, a lubricant ratio of 30%, a lubricant spraying speed of 200g/min, a mixing speed of 8rpm, and a mixing time of 60min.

Checking the results, in the case of sample 15, the catalyst desorption rate was 20%, workability 'good', productivity 'medium', De-NOx efficiency 'excellent', and catalyst dispersibility 'medium'. In the case of sample 15, it was confirmed that the denitrification performance was excellent, but the productivity was low.

In Samples 16 to 19, the ranges of the lubricant injection speed (Samples 16 and 17) and the ranges of the lubricant ratio (Samples 18 and 19) were confirmed based on the conditions of Sample 10, which is a preferred embodiment.

In Sample 16, the other conditions were the same as those of Sample 10, and the lubricant injection rate was increased to 270 g/min.

Checking the results, in the case of sample 16, the catalyst desorption rate was 20%, workability 'sufficient', productivity 'low', De-NOx efficiency 'poor', and catalyst dispersibility 'low'. When the lubricant spraying speed exceeds 270 g/min, dispersibility deteriorates, and workability and productivity also decrease, making it difficult to mass-produce the product.

In Sample 17, the other conditions were the same as those of Sample 10, and the lubricant injection rate was reduced to 130 g/min.

Checking the results, in the case of sample 17, the catalyst desorption rate was 20%, workability 'good', productivity 'medium', De-NOx efficiency 'poor', and catalyst dispersibility 'low'. When the lubricant injection speed is less than 130 g/min, agglomeration of the catalyst occurs, and holes are formed in the sheet or the sheet is torn due to the agglomeration of the catalyst.

In sample 18, other conditions were the same as in sample 10, and the lubricant ratio was reduced to 25%.

Checking the results, in the case of sample 18, the catalyst desorption rate was 25%, workability 'sufficient', productivity 'low', De-NOx efficiency 'poor', and catalyst dispersibility 'low'. When the lubricant ratio was less than 25%, it was confirmed that the sheet was hard and it was difficult to control the thickness.

In sample 19, other conditions were the same as in sample 10, and the lubricant ratio was increased to 35%.

In this case, it was confirmed that production was impossible and the possibility of fire increased. Increasing the lubricant to more than 35% can pose a safety concern.

According to at least one embodiment described above, in the present invention, a PTFE membrane is applied to filter dust in exhaust gas from the filter surface, and NOx and dust are removed by a technology for removing nitrogen oxides by reacting NOx in a bag filter supported with a catalyst. can be removed at the same time. In addition, it becomes possible to manufacture a catalytic filter using a catalytic fiber rather than a catalytic filter of a coating method, which is dependent on overseas technology and products.

The embodiments described in this specification and the accompanying drawings merely illustrate some of the technical ideas included in the present invention by way of example. Therefore, since the embodiments disclosed in this specification are intended to explain rather than limit the technical spirit of the present invention, it is obvious that the scope of the technical spirit of the present invention is not limited by these embodiments. All modifications and specific examples that can be easily inferred by those skilled in the art within the scope of the technical idea included in the specification and drawings of the present invention should be construed as being included in the scope of the present invention.

Claims (20)

In the powder mixing method for producing PTFE fibers by mixing a De-NOx catalyst and a lubricant with PTFE powder,
In the process of putting PTFE powder and De-NOx catalyst powder in a mixer that mixes the powder by repeated falling using gravity and centrifugal force and rotating it, a lubricant is sprayed on the powder to create a mixed powder,
The lubricant is adjusted so that it is sprayed only on the PTFE powder and the De-NOx catalyst powder without being sprayed on the wall surface of the mixer, and the De-NOx catalyst powder is 0.5% by weight or more and less than 0.7% by weight of the total weight. mixing method. delete delete According to claim 1,
The lubricant is
Powder mixing method for producing PTFE fibers, characterized in that 27% by weight or more and 29% by weight or less of the total weight. According to claim 4,
The injection speed of the lubricant is,
Powder mixing method for producing PTFE fibers, characterized in that 150 g / min or more and less than 250 g / min. According to claim 4,
The powder mixing method for producing PTFE fibers, characterized in that the rotation speed of the mixer is 10 rpm or more and 14 rpm or less, and the mixing time is 40 minutes or more and 70 minutes or less. In the manufacturing method of PTFE fiber for manufacturing a PTFE membrane catalyst filter manufactured through a mixing process, an aging process, a compression process, an extrusion process, a rolling process, a sintering process, an oil making/stretching process, and a slitting process,
The mixing process is
In the process of putting PTFE powder and De-NOx catalyst powder in a mixer that mixes the powder by repeated falling using gravity and centrifugal force, and rotating it, a lubricant is sprayed on the powder to create a mixed powder, and the lubricant is applied to the wall of the mixer. The PTFE fiber manufacturing method, characterized in that it is controlled to be sprayed only on the PTFE powder and the De-NOx catalyst powder without being sprayed, and the De-NOx catalyst powder is 0.5% by weight or more and less than 0.7% by weight of the total weight. delete delete According to claim 7,
The lubricant is
A method for producing a PTFE fiber, characterized in that it is 27% by weight or more and 29% by weight or less of the total weight. According to claim 10,
The injection speed of the lubricant is,
A method for producing a PTFE fiber, characterized in that 150 g / min or more and less than 250 g / min. According to claim 10,
The method for producing PTFE fibers, characterized in that the rotational speed of the mixer is 10 rpm or more and 14 rpm or less, and the mixing time is 40 minutes or more and 70 minutes or less. In the method for manufacturing a PTFE membrane catalyst filter using PTFE fibers manufactured through a mixing process, an aging process, a compression process, an extrusion process, a rolling process, a sintering process, an oil making/stretching process, and a slitting process,
The mixing process is
In the process of putting PTFE powder and De-NOx catalyst powder in a mixer that mixes the powder by repeated falling using gravity and centrifugal force, and rotating it, a lubricant is sprayed on the powder to create a mixed powder, and the lubricant is applied to the wall of the mixer. A method for manufacturing a PTFE membrane catalyst filter, characterized in that it is not sprayed but sprayed only on the PTFE powder and the De-NOx catalyst powder, and the De-NOx catalyst powder is 0.5% by weight or more and less than 0.7% by weight of the total weight. delete delete According to claim 13,
The lubricant is
A method for manufacturing a PTFE membrane catalyst filter, characterized in that it is 27% by weight or more and 29% by weight or less of the total weight. According to claim 16,
The injection speed of the lubricant is,
Method for manufacturing a PTFE membrane catalyst filter, characterized in that 150g / min or more and less than 250g / min. According to claim 16,
The method for manufacturing a PTFE membrane catalyst filter, characterized in that the rotation speed of the mixer is 10 rpm or more and 14 rpm or less, and the mixing time is 40 minutes or more and 70 minutes or less. A PTFE fiber manufactured by the method of any one of claims 7, 10, 11 and 12. A PTFE membrane catalytic filter manufactured by the method of any one of claims 13, 16, 17 and 18.

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