JPH0544208U - Rotary single chamber filter - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object to provide an effective cleaning device for a filter cloth of a rotary single-chamber type filter. [Structure] A cleaning slit provided at an appropriate position below the blow gas slit of the valve shoe, a connecting pipe connecting the cleaning slit and the valve bar, and an intermediate position between the blow gas slit and the cleaning slit. A rotary single-chamber type filtering machine characterized in that a spray means for spraying a cleaning liquid is provided on the outer surface of the filter cloth.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rotary single-chamber filter, and more particularly to a filter cloth cleaning device for a rotary single-chamber filter.

[0002]

[Prior Art]

 The rotary single-chamber type filter is a single-chamber type and can increase the opening ratio of the drum and the diameter of the filtrate tube, so it has a large filtering capacity and can maintain a uniform flow of the washing liquid throughout the cake. It has many advantages such as high cleaning effect, easy blowback air to blow back easily to easily remove even a cake with poor filtration property, and simple structure to reduce maintenance and easy maintenance. Because it has, it is widely used in many fields such as general chemical industry, fertilizer industry, metal industry, food industry.

The structure of a conventional rotary single-chamber filter will be described. FIG. 2 is a cross-sectional view showing the entire structure of the rotary single-chamber type filter, and FIG. 3 is a cross-sectional view of the cake peeling device and the filter cloth cleaning device of the filter. In the figure, reference numeral 1 denotes a rotary drum driven by a variable speed reducer (not shown), on the outer peripheral surface of which a filter bridge 2 is provided continuously along the circumference, and a filter cloth 3 is sectioned on the surface thereof. It has been stretched. On the peripheral wall of the drum 1, per filter bridge, two rows of axially small filtrate holes 4 having a small diameter are provided at an appropriate pitch. Reference numeral 5 is a vat for storing the stock solution F, and the lower part of the drum 1 is immersed to form a filtration area. A center pipe 6 is axially fixed to the center of the drum, and a filtrate pipe 7 is connected to the lower part of the center pipe for dipping the filtrate into the filtration area of the drum and sucking the filtrate out.

Reference numeral 8 denotes a valve shoe made of a synthetic resin such as Teflon that slidably contacts the inner peripheral surface of the drum 1 with a small gap. A plurality of valve shoes are fixed to the center pipe 6 by a valve bar 9, respectively, and are arranged in the drum axial direction. Are connected in a row. A narrow slit 10 for introducing a blow gas such as nitrogen gas for cake peeling into the filtrate hole 4 is provided in the upper portion of the valve shoe 8 in parallel with the axial direction of the drum, and in the lower portion of the valve shoe 8, A slit 11 for cleaning the filter cloth is provided in the axial direction of the drum, and is connected to a cleaning liquid pipe 13 in the center pipe 6 via a flexible pipe 12.

The operation of the conventional filter cloth cleaning device of the rotary single-chamber type filter having the above-mentioned configuration will be described. The cake C formed on the surface of the filter cloth 3 in the filtration area of the stock solution vat 5 is drained as the drum 1 rotates, passes through the cake cleaning section 15, and reaches the upper portion of the valve shoe 8. Here, the gas for back blowing the filter cloth flows in the order of the center pipe 6, the valve bar 9, the blow gas slit 10 and the filtrate hole 4, flows into the filter bridge 2, and blows from the back side of the filter cloth 3. The cake C is peeled off and discharged to the outside of the machine through the cake chute 14. When the filter bridge 2 from which the cake C on the surface of the filter cloth has been removed reaches the cleaning liquid slit 11 of the valve shoe 8 next time, the cleaning liquid pipe 13, the flexible pipe 12, the liquid slit 11 and the filtrate hole 4 flow in this order. However, it flows into the filter bridge 2 and is washed from the back side of the filter cloth 3. The filter cloth thus washed again enters the filtration zone and the filtration operation is repeated.

[0006]

[Problems to be solved by the device]

 As a result of examination, it was found that the above-mentioned conventional filter cloth cleaning device for a rotary single-chamber type filter has the following problems. That is, the filter cloth 3 is washed when the cleaning liquid is flowing into the filter bridge 2, and this is when the filtrate hole 4 of the filter bridge to be cleaned comes into contact with the cleaning liquid slit 11 of the valve shoe 8. . However, this filter is often operated by rotating the drum at a high speed in order to increase the filtration capacity, and since the drum 1 is operated under external pressure, the diameter and number of filtrate holes are also designed due to the strength design. It was found that the time during which the cleaning liquid slit 11 and the filtrate hole 4 were in contact with each other was extremely short, for example, 0.1 to 0.2 seconds due to the limitation. It was also found that the amount of cleaning liquid flowing into the filter bridge in this short time was naturally limited because it was a liquid, and it was not sufficient as the amount of cleaning liquid for the filter cloth. The present invention has been made based on the above problems of the prior art, and an object thereof is to provide an effective cleaning device for a filter cloth of a rotary single-chamber type filter.

[0007]

[Means for Solving the Problems]

 The gist of the present invention for solving the above-mentioned problems is that a rotary drum (1) having a filter cloth (3) stretched around a peripheral surface through a filter bridge (2) is axially attached to a center pipe (6). Then, the lower part is immersed in the undiluted solution vat (5) and filtered, and the cake formed on the outer surface of the filter cloth (3) has a valve shoe (8) fixed to the center pipe (6) by a valve bar (9). In a rotary single-chamber type filter that separates and collects by the gas blown from the blow gas slit (10), a cleaning slit provided at an appropriate position below the blow gas slit (10) of the valve shoe (8). (16), a connecting pipe (17) for communicating the cleaning slit (16) with the valve bar (9), an intermediate position between the blow gas slit (10) and the cleaning slit, and the cleaning liquid is sprayed on the outer surface of the filter cloth. In rotary single-chamber filtration unit, characterized in that a and spray means (18) that.

[0008]

[Action]

 The filter bridge (2) from which the cake on the filter cloth has been removed by the blow-back comes to a position facing the spraying means (18) as the drum (1) rotates, and the high-speed cleaning solution is filtered. And the cake remaining in the filter cloth is washed away and the filter cloth becomes wet. In this state, when the filter bridge (2) reaches the position of the cleaning slit (16) provided in the lower position of the valve shoe (8), the blowing gas is discharged from the filtrate bridge (4) through the filter bridge (2). ), And then pass through the filter cloth from the back side at high speed. At this time, since the filter cloth is in a wet state, the resistance of the openings is large, so that the cake fine particles remaining in the filter cloth are efficiently removed and washed.

In the above operation, even if the cleaning liquid is sprayed at a high speed, the filter cloth is supported by the filter bridge (2) and therefore is not likely to be damaged. In addition, even if the filtrate hole (4) of the filter bridge is in contact with the cleaning slit (16) for a short time, the fluid flowing into the filter bridge is a gas body, so the flow velocity should be 5 to 10 times that of the liquid. Therefore, the flow rate required for cleaning the filter cloth can be secured. Furthermore, if the distance between the blow gas slit (10) and the cleaning slit (16) of the valve shoe (8) is adjusted so that both do not contact the filtrate hole (4) at the same time, a small amount of gas is required. It can be cleaned more effectively.

[0010]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of the essential parts of an embodiment of the present invention. In the figure, the same members as those in FIGS. 2 and 3 are denoted by the same reference numerals. That is, 1 is a rotating drum, 2 is a filter bridge having a filter cloth 3 stretched on the surface, 4 is a filtrate hole formed in the peripheral wall of the drum 1, 6 is a center pipe fixed to the center of the drum 1, Reference numeral 8 is a valve shoe that is in sliding contact with the inner wall of the drum, and is fixed to the center pipe 6 by a hollow valve bar 9. Reference numeral 10 is an elongated blow gas slit provided in the upper portion of the valve shoe 8 in parallel with the drum shaft, and 16 is an elongated cleaning slit provided in the lower portion of the valve shoe 8 in parallel with the drum shaft. A pipe 17 communicates with the inside of the valve bar 9. Reference numeral 18 is a spray means provided at an intermediate position between the blow gas slit 10 and the cleaning slit 16 so as to face the filter cloth surface, and a spray pipe 18A horizontally installed and a spray pipe 18 at a proper interval in the axial direction of the drum. It is composed of a plurality of spray nozzles 18B screwed to the pipe 18A.

The operation of the embodiment having the above configuration will be described. When the filter bridge 2 reaches the position of the blow gas slit 10 of the valve shoe 8 as the drum 1 rotates, the blow gas flows into the filter bridge 2 through the filtrate hole 4 and blows the filter cloth 3 from the back side. Therefore, the cake is peeled off from the filter cloth and discharged through the cake chute 14 to the outside of the machine. The filter bridge 2 from which the cake has been peeled off in this manner rotates downward and reaches a position facing the spraying means 18, the high-speed cleaning liquid is sprayed onto the filter cloth, and the cake remaining in the filter cloth is discharged. As the part is washed away, the filter cloth becomes wet. In this state, when the filter bridge 2 further rotates downward and the filtrate hole 4 contacts the cleaning slit 16, a considerable amount of blowing gas flows into the filter bridge 2 and passes through the filter cloth at a high flow rate. Meanwhile, the cake fine powder remaining in the filter cloth is efficiently removed and washed.

[0012]

[Effect of the device]

 According to the present invention having the above-described structure and operation, since the gas having a high flow rate is blown from the back side of the filter cloth immediately after the cleaning liquid is sprayed by the spray means, the cake fine powder remaining in the filter cloth is efficiently removed. In addition to being well removed, the cleaning liquid is sprayed on the filter cloth supported by the filter bridge, so that there is no risk of damaging the filter cloth.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts of a filter cloth cleaning device of the present invention.

FIG. 2 is a cross-sectional view showing the overall structure of a conventional rotary single-chamber filter.

FIG. 3 is a cross-sectional view of a main part of a filter cloth cleaning device for a conventional rotary single-chamber filter.

[Explanation of symbols]

1: rotating drum, 2: filter bridge, 3: filter cloth,
4: Filtrate hole, 5: Stock solution vat, 6: Center pipe,
7: filtrate tube, 8: valve shoe, 9: valve bar, 1
0: gas slit, 11: liquid slit, 12: flexible pipe, 13: cleaning liquid pipe, 14: cake chute,
15: cake washing part, 16: slit for washing, 17: connecting pipe, 18: spraying means, C: cake, F: stock solution.

Claims (1)

[Scope of utility model registration request] 1. A rotary drum (1) having a filter cloth (3) stretched around a peripheral surface through a filter bridge (2) is axially attached to a center pipe (6), and the lower part is immersed in a stock solution vat (5). The cake formed on the outer surface of the filter cloth (3) is separated by the gas blown from the blow gas slit (10) of the valve shoe (8) fixed to the center pipe (6) by the valve bar (9). In the rotary single-chamber type filtering machine that collects and recovers, a cleaning slit (16) provided at an appropriate position below the blow gas slit (10) of the valve shoe (8), the cleaning slit (16) and the valve bar ( And a spray means (18) for injecting a cleaning liquid onto the outer surface of the filter cloth, which is provided at an intermediate position between the blow gas slit (10) and the cleaning slit. That rotary single-chamber filtration unit.