JPH0796111A - Horizontal vacuum belt filter - Google Patents

Abstract

PURPOSE:To prepare a horizontal vacuum belt filter of low cost and high performance and of economicity by which constraints to kinds of endless filter cloth belts in use are circumvented and which is suitable for increasing its capacity by running a filter cloth belt with an accompanying belt having sufficient permeability and tensile strength and dispensing with a filter function. CONSTITUTION:Original liquid slurry fed on a filter cloth belt 1a is filtered and the obtained cake is washed when evacuating boxes 2-1 to 2-4 are under vacuum. When the evacuating boxes 2-1 to 2-4 are switched to atmospheric pressure, by the intermittent movement of the belt 1a, the cake is discharged from the front end of a horizontal belt part. An endless belt 1a which makes a U-turned downwards from a common front end roll 5b-3 of the horizontal belt part and then extends backwards to form an outside large loop, and an endless accompanying belt 1b which extends forwards in contact with the lower surface of the horizontal belt part and makes a U-turn downwards from the common front end roll 5b-3 and then is formed inside the endless filter cloth belt 1a to form an inside small loop are together provided.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a horizontal vacuum belt filter.

[0002]

2. Description of the Related Art A horizontal type vacuum belt filter can flexibly respond to the properties of a stock solution slurry by controlling the filtration area, belt speed, etc., and the produced cake can be washed countercurrently in multiple stages. There is an advantage that the cleaning water can be surely and efficiently cleaned. Therefore, this type of belt filter is widely used in many fields such as chemical industry, mining industry, metal industry, and food industry. Conventionally used horizontal type vacuum belt filters are roughly classified into the following two types.

(1) Intermittent reciprocating type This is a plurality of flat rectangles having the same width as the belt width along the lower surface of the horizontal portion of the endless filter cloth belt as shown in Japanese Patent Publication No. 55-33368. The vacuum evacuation boxes are arranged in tandem, and a plurality of vacuum evacuation boxes and filter cloth belt are simultaneously advanced integrally for a predetermined stroke, and when the evacuation of the vacuum evacuation boxes is stopped, the vacuum evacuation boxes are driven by a drive cylinder. It is a model that repeats the action of returning to the original position. While this type has the advantage of being able to discharge the cake substantially continuously, it requires a thick and strong filter cloth belt suitable for intermittent movement,
Furthermore, the drive system of the vacuum chamber is complicated, the cost is high, and the size of the machine is limited.

(2) Fixed vacuum evacuation box type As shown in Japanese Patent Publication No. 55-26886, the vacuum evacuation box is fixed, and the inside of the box is evacuated and opened to the atmosphere by switching its three-way switching valve. It is repeated alternately in two states, and the filtration operation is performed in a vacuumed state, and the filter cloth is moved and the cake is discharged in an open state to the atmosphere.
This type has the disadvantage that it is intermittent because the cake is discharged only when the filter cloth is moved.
It has the advantages of relatively simple structure and low equipment cost.

[0005]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above circumstances, and eliminates the restriction on the type of endless filter cloth belt to be used, and is low in cost and suitable for increasing the capacity of the apparatus. The purpose is to provide a high performance and economical horizontal vacuum belt filter.

[0006]

To this end, the invention of claim 1 is an endless filter cloth belt which is circulated around a plurality of laterally parallel rolls which are vertically and vertically arranged on a vertical plane. Along the lower surface of the upper horizontal belt part, a plurality of rectangular flat vacuum evacuation boxes are provided at fixed intervals in contact with the bottom surface of the horizontal belt part, and filtration of the stock solution slurry supplied on the filter cloth belt when the vacuum evacuation box is in vacuum is provided. And in the horizontal vacuum belt filter for washing the cake obtained, when the vacuum chamber is switched to atmospheric pressure, by intermittent movement of the filter cloth belt, to discharge the cake from the front end of the horizontal belt portion. , An endless filter cloth belt that makes a large outer loop after making a U-turn downward from a common roll at the front end of the horizontal belt section, and extends forward while contacting the lower surface of the horizontal belt section. A horizontal vacuum belt filter, characterized in that the common front roll equipped with an endless escort belt that forms the endless filter cloth inside formed inside the small loop of the belt After U-turn downward.

According to a second aspect of the present invention, in the first aspect of the present invention, in the horizontal belt portion, a double horizontal surface is provided between the lower surface of the endless filter cloth belt and the upper edge of the vacuum evacuation box with an endless accompanying belt having air permeability. Driving a horizontal vacuum belt filter, characterized in that a belt portion is formed and the endless filter belt of the horizontal belt portion is moved forward by a frictional force by moving the endless accompanying belt forward by a driving roll. Is the way.

[0008]

According to such a construction, the endless companion belt (hereinafter referred to as the companion belt) is given a large tension, and the endless filter cloth belt (hereinafter referred to as the filter cloth belt) superposed on the horizontal portion thereof has a slack. All you need to do is apply a small amount of tension. The filter cloth belt on which the filtered cake is placed has an effect of vacuuming at the horizontal portion of the upper surface, and is kept in close contact with the companion belt. After the evacuation is stopped and the evacuation box is set to the atmospheric pressure, the companion belt is driven by the drive roll.
The filter cloth belt moves integrally with the companion belt by the action of the frictional force of 5a-3. Therefore, as compared with the conventional type belt filter that only intermittently moves the filter cloth belt, the restriction on the strength of the filter cloth belt is greatly reduced. It is also possible to use a simple filter cloth belt. On the other hand, since the accompanying belt can use a cloth having a strength higher than that of the ordinary filter cloth, the machine length can be increased to 1.5 to 2 times as long as that of the conventional belt filter of the same type, and the size can be increased.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, an embodiment of the present invention will be described. FIG. 1 is an overall side view thereof, and FIG. 2 is a transverse sectional view taken along the line II--II of FIG.

1 to 2, a solid line 1a indicates a filter cloth belt which reaches a front end common roll 5a-3 through a rear end roll 5a-1, a rear common guide roll 5, a rear common intermediate roll 5a-2, Here, after making a U-turn downward, an outer loop which returns to the trailing end roll 5a-1 via the filter cloth tension roll 7a, front intermediate roll 7a-1, rear intermediate roll 7a-2, filter cloth belt meandering correction roll 6a is formed. is doing.

A dashed line 1b indicates a companion belt, which reaches the front end common roll 5a-3 from the rear common guide roll 5 through the rear common intermediate roll 5a-2, and then makes a U-turn downward to make a front intermediate roll 8b-. 1, an inner loop returning to the rear common guide roll 5 via the companion belt driving roll 8, the rear intermediate roll 8b-2, the companion belt tension adjusting roll 7b, the intermediate rolls 8b-3 and 8b-4, and the companion belt meandering correction roll 6b. Form. Here, a filter cloth belt 1a forming an outer loop and a running belt 1b forming an inner loop.
Is the rear common intermediate roll 5a-2 and the front end common roll 5
A double horizontal belt portion (hereinafter referred to as a horizontal belt portion) which is vertically overlapped with a-3 is formed.

Reference numerals 2-1, 2-2 and 2-3 denote flat vacuum evacuation boxes each having the same width as the width of the filter cloth belt. The upper ends of rectangles of the same size are opened, and the bottom plates are respectively provided with vacuum evacuation pipes 11. , 12 are connected. The lower ends of the evacuation pipes 11 and 12 have vacuum receivers 16 and 1 respectively.
7, a filtrate pump 14 and a cleaning solution pump 15 are connected to the lower ends of the respective vacuum receivers, and a common vacuum pump 13 is connected to the upper ends thereof. 9,
Reference numeral 10 is a three-way electromagnetic switching valve attached to each of the evacuation pipes 11 and 12, and communicates the inside of each evacuation box 2-1 and 2-3 with the vacuum receivers 16 and 17 during the filtration operation to discharge the cake. Each is selectively remotely controlled to communicate with the atmosphere.

Reference numeral 18 denotes a filter cloth belt tension adjusting hydraulic cylinder which adjusts the tension of the filter cloth belt 1a by moving the trailing end roll 5a-1 in the front and rear direction, and 19 moves the accompanying belt tension adjusting roll 7b in the front and rear direction. This is a hydraulic cylinder for adjusting the tension of the accompanying belt. 3 and 4 are located slightly above the positions of the rear end of the double horizontal belt part and the center part, respectively, and the stock solution slurry and cleaning solution
These are a slurry feeder and a cleaning liquid feeder, which are supplied to the center of the heavy horizontal belt near the rear end. Reference numeral 20 denotes a mesh plate in which the liquid is freely flown, which is mounted in the vacuum evacuation boxes 2-1 to 2-4, and the surface thereof is smooth so that the accompanying belt can slide smoothly. 21 is a filter cloth cleaning means.

In such an apparatus, at the time of filtration, the vacuum evacuation boxes 2-1, 2-2, 2-3, 2-4 are connected to the vacuum receivers 16 and 17 by the three-way electromagnetic switching valves 9 and 10 to form a vacuum. The pressure is reduced by pulling. When a cake is formed on the filter cloth belt by filtration, the three-way electromagnetic switching valves 9 and 10 switch the vacuum chambers to the atmosphere, so that the differential pressure acting on the filter cloth belt becomes zero. The frictional force between the filter cloth belt and the vacuum box decreased, the filter cloth belt moved forward lightly with the movement of the companion belt, and the cake that had moved above the vacuum evacuation boxes 2-3 and 2-4 was in vacuum. It is washed by spraying the washing liquid. The cake washed in this way is peeled off from the filter cloth belt by a scraper (not shown) when the filter cloth belt moves, and the cake U is moved downward in the front common roll 5a-3 of the filter cloth belt.
It falls from the filter cloth belt at the time of turn.

In this way, by intermittently repeating the vacuuming action by the vacuuming chamber and the atmospheric pressure introducing action of the vacuuming chamber, the filtering action of the slurry by the filter cloth belt proceeds at the batch speed.

[0016]

According to the present invention having the above-mentioned structure and action, the following effects can be obtained, so that the present invention is industrially extremely useful. In the conventional device of this type, since only the filter cloth belt is moved around by being directly wound around the driving roll, a large tension is applied to the filter cloth belt, so that the weaving method and the tensile strength thereof are greatly restricted. . However, the device of the present invention has sufficient air permeability and tensile strength,
The filter cloth belt is run along with the rung belt which does not require the filtering function. As the accompaniment belt, for example, a monofilament of polyester or polypropylene can be adopted. By the way, this type of monofilament belt can apply a tension of 2 to 3 times that of a conventional filter cloth belt, and the length can be extended and the size can be increased at such a low price. Further, as the filter cloth belt, a filter cloth made of fine fibers which cannot be used alone can be used. As a result, by adopting a special filter cloth belt, it becomes possible to filter fine particles which could not be processed by this type of filter in the past.

[Brief description of drawings]

FIG. 1 is an overall side view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG.

[Explanation of symbols]

1a; filter cloth belt, 1b; accompaniment belt, 2-1 to 2-
4; vacuum evacuation box, 3; stock solution slurry feeder, 4; cleaning solution feeder, 5; rear common guide roll, 5a-
1; rear end roll, 5a-2; rear common intermediate roll, 5a
-3; front end common roll, 6a; filter cloth belt meandering correction roll, 6b; accompanying belt meandering correction roll, 7a; filter cloth tension roll, 7a-1; front intermediate roll, 7a-2; rear intermediate roll, 7b; Accompanied belt tension adjusting roll, 8; Accompanied belt driving roll, 8b-1 to 4; Intermediate roll, 9, 1
0: Three-way solenoid valve, 11, 12; Vacuum piping, 1
3; vacuum pump, 14; filtrate pump, 15; washing liquid pump, 16, 17; vacuum receiver, 18; hydraulic cylinder for adjusting tension of filter cloth belt, 19; hydraulic cylinder for adjusting tension of accompanying belt, 20; mesh plate, 21; Filter cloth cleaning means.

Claims (2)

[Claims] 1. An upper end of an endless filter cloth belt which is circulated around a plurality of lateral parallel rolls arranged vertically and vertically and vertically and vertically, and contacts the lower end of a horizontal belt portion. A plurality of rectangular flat vacuum evacuation boxes are fixed and provided at appropriate intervals, the stock solution slurry supplied onto the filter cloth belt at the time of vacuum of the vacuum evacuation box is filtered, and the obtained cake is washed, and the vacuum evacuation is performed. In a horizontal vacuum belt filter that discharges cake from the front end of the horizontal belt portion by intermittent movement of the filter cloth belt when the box is switched to the atmospheric pressure, a U from the front end common roll of the horizontal belt portion is moved downward. An endless filter cloth belt that extends backward and forms a large outer loop after turning, and extends forward while contacting the lower surface of the horizontal belt portion, and extends downward from its common front end roll.
A horizontal vacuum belt filter, comprising an endless traveling belt formed inside the endless filter cloth belt after turning and forming an inner small loop. 2. The double horizontal belt portion according to claim 1, wherein an endless traveling belt having air permeability is interposed between the lower surface of the endless filter cloth belt and the upper edge of the vacuum evacuation box in the horizontal belt portion. A method for driving a horizontal vacuum belt filter, wherein the endless filter belt of the horizontal belt portion is moved forward by a frictional force by moving the endless accompanying belt forward by a drive roll.