JP4309722B2 - Flow-on paper making equipment - Google Patents

Description

  The present invention relates to a flow-on papermaking apparatus, and more particularly to a technique for removing moisture from a slurry-like substance.

  Conventionally, among building materials such as exterior materials, there are cement-based inorganic boards (fiber-reinforced cement boards) that are manufactured by making a slurry containing cement and aggregates as a main component and containing reinforcing fibers, Among the methods for producing an inorganic plate from slurry, there is a flow-on papermaking method. A specific example of such a flow-on papermaking method is disclosed in Patent Document 1 and is not shown. In this method, a high-concentration slurry is allowed to flow down from a flow box onto a papermaking belt. A green sheet is formed by dehydrating naturally and forcibly from the lower surface of the slurry traveling with the belt.

In the flow-on papermaking apparatus used in this flow-on papermaking method, a vibration exciter functioning as a slurry vibrating means for vibrating the slurry flowing down on the papermaking belt is disposed above the papermaking belt. In addition, the slurry is vibrated to make the thickness of the green sheet uniform or to adjust the formation of the upper surface of the green sheet. Further, as another example of the flow-on papermaking method, there is one disclosed in Patent Document 2, which is not shown, but in this method, a sheet-like defoaming means is brought into contact with the upper surface of the slurry. Then, it is performed to prevent the discharge traces of the bubbles contained in the slurry from remaining on the upper surface of the green sheet.
Japanese Patent Laid-Open No. 10-323811 Japanese Patent No. 2002-178318

  By the way, in the flow-on papermaking method according to the conventional example, the following inconvenience occurs. That is, in the flow-on papermaking method of Patent Document 1, it is unavoidable that moisture, so-called floating water, is generated on the upper surface of the slurry that has flowed down on the papermaking belt and is subjected to vibration. The moisture is not dehydrated unless it passes through the inside of the green sheet and reaches the lower surface. However, in this case, the dewatering efficiency becomes very poor and floating water tends to remain, resulting in poor surface formation of the produced green sheet.

  Further, in the flow-on papermaking method disclosed in Patent Document 2, the sheet-like defoaming means is brought into contact with the upper surface of the slurry, thereby preventing bubble marks from remaining on the upper surface of the green sheet. However, it is not always possible to remove the floating water generated on the upper surface of the slurry, and it is not possible to prevent the floating water from remaining, so that the surface texture of the green sheet has not been improved. It was a fact.

  The present invention was devised in view of these disadvantages, and it is possible to surely remove the water generated on the upper surface of the slurry, and to achieve a good surface formation of the green sheet. The purpose is to provide on-paper making equipment.

  In order to achieve the above object, a flow-on papermaking apparatus according to the first aspect of the present invention includes a water-permeable sheet in contact with an upper surface of a slurry that has flowed from a flow box onto a papermaking belt, and the water-permeable sheet. A scraper (draining plate) disposed opposite to the slurry and along a direction intersecting the traveling direction of the papermaking belt, and a water absorbing means for sucking water scraped off by the scraper. It is characterized by.

  The flow-on papermaking apparatus according to the second aspect of the present invention is the flow-on papermaking apparatus according to the first aspect, wherein the slurry vibrating means for applying vibration to the slurry via the water-permeable sheet is provided from the scraper along the traveling direction of the papermaking belt. Is also arranged at a position on the upstream side.

  A flow-on papermaking apparatus according to a third aspect of the present invention is the flow-on paper making apparatus according to the first or second aspect, wherein the scraper is provided with scraper vibration means for vibrating itself.

  The flow-on papermaking apparatus according to the present invention as set forth in claim 4 is the apparatus according to any one of claims 1 to 3, comprising a plurality of scrapers, and each scraper is a progression of a papermaking belt. It arrange | positions in the state adjoined along the direction which cross | intersects a direction, It is characterized by the above-mentioned.

  The flow-on papermaking apparatus according to the present invention as set forth in claim 5 is the apparatus according to any one of claims 1 to 3, comprising a plurality of scrapers, each scraper being in the direction of travel of the papermaking belt. It arrange | positions in the state spaced apart along, It is characterized by the above-mentioned.

  In the flow-on papermaking apparatus according to the first aspect of the present invention, moisture (floating water) generated on the upper surface of the slurry flowing down on the papermaking belt is scraped off by a scraper through the water-permeable sheet. Thus, the water collected by scraping is removed by being sucked by the water absorbing means. Therefore, it is possible to make the thickness of the green sheet uniform using a water permeable sheet and to reliably remove moisture generated on the upper surface of the slurry, and as a result, the surface formation of the green sheet can be greatly improved. An excellent effect is obtained.

  In the flow-on papermaking apparatus according to the second aspect of the present invention, since the slurry vibrating means for applying vibration to the slurry is disposed at the upstream position along the traveling direction of the papermaking belt, moisture is more efficiently removed from the slurry. Can be discharged. Therefore, the effect of the structure according to claim 1 is further enhanced.

  In the flow-on papermaking apparatus according to the third aspect of the present invention, since the scraper itself is vibrated by the scraper vibrating means, it is possible to prevent the scraper itself and the water-permeable sheet with which the scraper is in contact with the scraper. It is possible to suppress the slurry from being deposited around As a result, it is possible to achieve an effect of realizing maintenance-free and long life of the entire apparatus.

  In the flow-on papermaking apparatus according to the present invention described in claim 4, a plurality of scrapers are arranged adjacent to each other in a direction intersecting the traveling direction of the papermaking belt, and according to the present invention according to claim 5. In the flow-on papermaking apparatus, a plurality of scrapers are arranged in a state of being separated along the traveling direction of the papermaking belt. Therefore, even if any one of the scrapers is damaged, the function is not lost, and moisture generated on the upper surface of the slurry can be reliably removed.

  A flow-on papermaking device that can reliably remove the water generated on the upper surface of the slurry flowing down on the papermaking belt and can improve the formation of the green sheet has been realized.

  1 is a side view showing the overall structure of a flow-on papermaking apparatus according to an embodiment of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is an explanatory view showing a plan view shape of an opening formed in an upper suction box. It is. 4 is a side view showing the overall structure of the flow-on papermaking apparatus according to the first modification, FIG. 5 is a plan view thereof, and FIG. 6 is a side view showing the overall structure of the flow-on papermaking apparatus according to the comparative example. FIG.

  FIG. 7 is a side view showing the overall structure of the flow-on papermaking apparatus according to the second modification, and FIG. 8 is a side view showing the overall structure of the flow-on papermaking apparatus according to the third modification. In addition, in each of these FIGS. 1-8, the same code | symbol is attached | subjected to the mutually same apparatus and components, and the overlapping description is abbreviate | omitted.

  As shown in FIGS. 1 and 2, the flow-on papermaking apparatus according to the embodiment of the present invention is supplied with a flow box 2 storing a high-concentration slurry 1 and the slurry 1 flowing down from the flow box 2. And an endless papermaking belt 3. Then, the upstream side position on the lower surface side of the papermaking belt 3, that is, the upstream side position along the traveling direction A of the papermaking belt 3, naturally absorbs moisture from the lower surface of the slurry 1 based on the action of gravity. A natural dewatering box 4 for removing water is disposed, and a lower suction box 5 for forcibly removing moisture from the lower surface of the slurry 1 by a pressure reducing action is disposed at a position downstream thereof. Has been.

  For example, the slurry 1 here is a product in which 5% pulp, 50% OPC, and 45% silica are dispersed in water, and the lower suction box 5 has a function of sucking moisture with a vacuum action of about 40 kPa. Have. Reference numeral 6 in the figure denotes a driving roll and 7 a driven roll. The papermaking belt 3 laid between the driving roll 6 and the driven roll 7 is driven along the traveling direction A at a speed of about 15 m / min. Is done.

  On the other hand, this flow-on papermaking apparatus is provided with a water-permeable sheet 11 that contacts the upper surface of the slurry 1 that has flowed down from the flow box 2 onto the papermaking belt 3, and faces the slurry 1 via the water-permeable sheet 11. 3, a single scraper 12 disposed along a direction crossing the traveling direction A, and an upper suction box 13 constituting water absorption means for sucking the water W scraped off by the scraper 12. Yes. The endless water-permeable sheet 11 produced using felt or the like having a predetermined thickness is supported by support rolls 14 arranged at appropriate locations, and is driven by the papermaking belt 3 via the slurry 1. It becomes the composition which is done.

  At this time, as shown in FIG. 3A, a number of openings 15 having a circular shape in plan view are formed on the lower surface of the upper suction box 13, and a flat plate-shaped scraper which is a draining plate made of neoprene rubber. The water W scraped by the water 12 is removed as it is sucked by the water ring pump 17 through the connecting pipe 16 from the opening 15 formed in the upper suction box 13. Here, the driving force of the water ring pump 17 is set to about 5 kW, and the suction pressure (vacuum degree) of the upper suction box 13 is about 1 to 3 kPa. Of course, these are not limited to these.

  By the way, the plan view shape of the opening 14 formed in the upper suction box 13 is not limited to a circular shape, and may be a rectangular shape as shown in FIG. As shown in FIG. 3C, only a single opening (slit) 14 having a large opening area may be formed instead of the large number of openings 14. The scraper 12 is not limited to being made of neoprene rubber, and may be made using urethane rubber or polyester.

  Moreover, it functions as a slurry vibration means for applying vibration to the slurry 1 on the papermaking belt 3 via the water-permeable sheet 2 at a position upstream of the papermaking belt 3 along the traveling direction A in the flow-on papermaking apparatus. A vibration exciter 18 is arranged. That is, since vibration is applied by the vibrator 18, the water W contained in the slurry 1 from the slurry 1 that is supplied onto the papermaking belt 3 and proceeds with the papermaking belt 3 to become a green sheet. It is released efficiently.

  Therefore, the moisture generated on the lower surface of the slurry 1 is naturally and forcibly removed by the natural dehydration box 4 and the lower suction box 5, and the moisture W generated on the upper surface of the slurry 1. Is scraped off by the scraper 12 and removed by the upper suction box 13 and the water ring pump 17 constituting the water absorption means. Therefore, with the flow-on papermaking apparatus according to the present embodiment, not only the water generated on the lower surface of the slurry 1 but also the water W generated on the upper surface can be efficiently removed.

  By the way, in the present embodiment, only the scraper 12 facing the slurry 1 through the water-permeable sheet 11 is provided, but the flow-on papermaking apparatus according to the first modification shown in FIGS. As described above, the scraper 12 may include a vibration exciter 19 that functions as a scraper vibration unit that vibrates itself. In this case, the vibration exciter 19 is set so that the amplitude of the scraper 12 in the vertical direction is about 0.1 mm and the frequency is about 3600 rpm.

  In the flow-on papermaking apparatus according to the first modification having such a configuration, the scraper 12 itself vibrates, so that this scraper 12 is compared with a case where the scraper 12 is fixedly supported. It becomes easy to prevent wear of the water-permeable sheet 11 with which the scraper 12 abuts itself. Of course, the amplitude of the scraper 12 is not limited to about 0.1 mm and the frequency is not limited to about 3600 rpm.

  Furthermore, the inventor of the present invention prepares a flow-on papermaking apparatus as a comparative example configured as shown in FIG. 6, and each of the flow-on papermaking apparatus according to the present embodiment and the first modification example. When these characteristic comparison tests were conducted after preparation, the test results as shown in Table 1 were obtained. In addition, the flow-on papermaking apparatus as a comparative example in this case does not include the scraper 12 and the upper suction box 13.

  That is, according to the test results shown in Table 1, in the flow-on papermaking apparatus according to the first modification in which the scraper 12 includes the vibration exciter 19, the scraper 12 that does not include the vibration exciter 19 As compared with the flow-on papermaking apparatus according to the provided example, it is clear that the deposits around the scraper 12 are reduced, and the wear of the water-permeable sheet 11 and the scraper 12 is greatly reduced. . Moreover, in any of the flow-on papermaking apparatus according to the example and the first modification, the dewaterability of the slurry 1 and the surface formation of the green sheet are good as compared with the flow-on papermaking apparatus according to the comparative example. You can also see that

  By the way, in the flow-on papermaking apparatus according to the embodiment and the first modification, the scraper 12 and the upper suction box 13 are integrated. However, the present invention is not limited to such a configuration. The configuration may be such that the box 13 is arranged separately from each other. Further, in the flow-on papermaking apparatus according to the embodiment and the first modification, the single scraper 12 and the upper suction box 13 are provided, but the present invention is not limited to such a configuration, and the second configuration shown in FIG. As in the modified example, the flow-on papermaking apparatus is provided with a plurality (two in the figure) of scrapers 12, and each scraper 12 is adjacent in a direction intersecting the traveling direction A of the papermaking belt 3. It may be arranged.

  Alternatively, as in the third modification shown in FIG. 8, it is assumed that the flow-on papermaking apparatus includes a plurality of (two in the drawing) scrapers 12, and each scraper 12 travels along the papermaking belt 3. It is good also as a structure arrange | positioned in the state spaced apart along A. FIG. Furthermore, although not shown in the drawing, it is a matter of course that a flow-on papermaking apparatus in which the configurations according to the second and third modified examples are combined with each other may be used.

  In the case of an industry that requires a solid-liquid separation process and the dehydrating property of the material to be dehydrated is not necessarily good, it is possible to use the flow-on papermaking apparatus configured according to the present invention. That is, for example, in the field of manufacturing ceramic materials such as exterior materials, roofing materials, exterior members, interior wall materials, sludge treatment fields, and also in the food production field, washing and drying pretreatment, etc. Necessary processing can be appropriately realized by using the flow-on paper making apparatus having such a configuration.

It is a side view which shows the whole structure of the flow on papermaking apparatus which concerns on the Example of this invention. It is a top view which shows the whole structure of the flow on papermaking apparatus which concerns on the Example of this invention. It is explanatory drawing which shows the planar view shape of the opening formed in the upper suction box with which the flow-on papermaking apparatus which concerns on the Example of this invention is provided. It is a side view which shows the whole structure of the flow on papermaking apparatus which concerns on a 1st modification. It is a top view which shows the whole structure of the flow on papermaking apparatus which concerns on a 1st modification. It is a side view which shows the whole structure of the flow on papermaking apparatus which concerns on a comparative example. It is a side view which shows the whole structure of the flow on papermaking apparatus which concerns on a 2nd modification. It is a side view which shows the whole structure of the flow on papermaking apparatus which concerns on a 3rd modification.

Explanation of symbols

1 Slurry 2 Flow box 3 Papermaking belt 12 Scraper 13 Suction box (water absorption means)
18 Exciter (slurry vibration means)
19 Exciter (scraper vibration means)
A Direction of papermaking belt W Moisture (floating water)

Claims (5)

A water-permeable sheet that contacts the upper surface of the slurry that has flowed down from the flow box onto the papermaking belt, and is disposed along a direction that faces the slurry via the water-permeable sheet and intersects the traveling direction of the papermaking belt. A flow-on paper making apparatus, comprising: a scraper that has been made, and water-absorbing means that sucks water scraped off by the scraper. 2. The flow-on according to claim 1, wherein slurry vibration means for applying vibration to the slurry via the water-permeable sheet is disposed at a position upstream of the scraper along the traveling direction of the papermaking belt. Paper making equipment. The flow-on papermaking apparatus according to claim 1 or 2, wherein the scraper includes scraper vibration means for vibrating itself. A plurality of scrapers are provided, and each scraper is arranged adjacent to each other in a direction intersecting with the traveling direction of the papermaking belt. Flow-on paper making equipment. The flow-on papermaking apparatus according to any one of claims 1 to 3, wherein a plurality of scrapers are provided, and each scraper is disposed in a state of being separated along the traveling direction of the papermaking belt. .

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