JPS6146210A - filtration press equipment - Google Patents

Abstract

PURPOSE:To obtain the titled device capable of reducing the water content of a cake and simplifying the mechanism by changing the flow of a filtrate after a filtration chamber is filled with the cake, and compressing the cake by deforming a water-impermeable membrane with the pressure of the material to be filtered. CONSTITUTION:The upper surface of a filter plate 8 constituting a filter press is formed to a corrugated shape, the recessed part is communicated with a filtrate discharge pipe 9, and a filter medium 11 is provided on the plate 8 and fixed with a filter frame 10 having a cut port 15 and a supporting part 12. A deformable water-impermeable membrane 13 consisting of a natural or a synthetic elastomer is furnished on said filter frame 10 and fixed with a pressing plate 14 to form a filter chamber 5 by the filter plate 8, the filter plate 10, and the water-impermeable membrane 13. A material to be filtered such as a slurry supplied under pressure enters the filter chamber 5 from the cut port 15, and a filtered cake is formed on the filter medium 11. As the filtration proceeds and the filter chamber 5 is filled with the formed filtered cake, the flow of the filtrate is changed due to the rapid reduction of an effective filter area to increase the cake pressing force, the water-impermeable membrane 13 is depressed by the pressure of the slurry, and the cake is pressed and dehydrated.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to solid-liquid separation technology in various industries including the chemical industry and the food industry, water and sewage sludge, and various waste liquids and waste treatment. This relates to a pressing device.

(Prior Art) In recent years, with the rapid development of industry, energy saving and environmental issues have become increasingly important. In particular, there is a need to improve the performance of solid-liquid separation technology used in various industries, waste liquid treatment, and the like. Along with this, there is a need to obtain a highly dehydrated cake with a water content as low as 1%. It is hoped that a separation device will emerge.

Generally, ordinary filtration devices such as the leaf filter shown in FIG. 2 are considered to be relatively simple solid-liquid separation devices. As shown in Fig. 2, this leaf filter supplies slurry from the slurry supply port 1 and flows it in the direction of the arrow.
The structure is such that the filtrate is passed through a filter leaf 2, the filtrate is taken out from a filtrate outlet 3, and the solid is taken out from a cake drain outlet 4.

Among the filtration devices, the filter press has a structure as shown in FIG. 3, in which the slurry is press-fitted into the filtration chamber 5 from the slurry supply port 1, and is tightened by a device 6 for filtration.

This filter press continues filtration even after the filter chamber is filled with filter cake, and if this dehydration cycle is particularly long,
By press-fitting the cake into the filter chamber 5, it is theoretically possible to expect the same dehydration effect as in a normal squeezing operation.

(Problems to be solved by the invention) However, in general, this filter press cannot be expected to have the dehydration effect as expected in theory, and it is difficult for the solid particles living there to move smoothly during the consolidation period, so it is partially insufficient. There are several problems, such as the fact that some areas are not dehydrated, and the solid particles sometimes move all at once, which places uneven stress on the filter plate and causes cracks in the filter plate. It is known. Furthermore, the above-mentioned leaf filter has a problem in that it is not possible to obtain a cake with a very low moisture content.

On the other hand, pressing equipment can achieve a higher degree of solid-liquid separation than filtration equipment and can obtain a cake with a lower water content.
Moreover, it is much more economical than thermal operations such as drying. A device consisting of a filter press with a squeezing mechanism has also been put into practical use, and by using this device it is possible to obtain a cake with a low moisture content.

However, starting with a filter press with a squeezing mechanism,
Generally speaking, squeezing equipment has higher performance than filtration equipment, but has the disadvantage that the equipment and mechanism are more complex, making the equipment more expensive and requiring much more effort to maintain. In recent years, there has been an increasing need to easily obtain a cake with a low moisture content by simply adding a pressing function.

The purpose of the present invention is to reduce the moisture content of the cake, which is currently desired in solid-liquid separation devices, by using a filtration and squeezing device that utilizes a change in effective filtration area and a deformable water-impermeable membrane. The objective is to simultaneously simplify the device and mechanism.

(Means for Solving the Problems) The present invention changes the flow of the filtrate by rapidly reducing the effective filtration area after the filter cake produced by the filtration operation of the object to be filtered fills the filter or during the progress of filtration. The present invention provides a filtration and squeezing device that is equipped with a filtering means and a water-impermeable membrane that can be deformed by the pressure of an object to be filtered, and that produces compression and dewatering of a produced filtration cake.

Hereinafter, the present invention will be explained in detail based on the drawings.

(Example) In FIG. 4, (a) is a horizontal filtration and pressing device,
(b) The figure shows a vertical filtration and pressing device. One or more filter plates 8 or filter leaves 2 in a horizontal or vertical pressure vessel 7
to be fixed. One or both sides of the filter plate 8 or filter leaf 2 serve as filtration surfaces. The pressure vessel 7 is equipped with a slurry supply port l,
The filter plate 8 or the filter leaf 2 is supported and fixed by the filtrate discharge pipe 9. The present invention has its special feature in the structure of the filter plate 8 or the filtrate 2, for example, the filter plate is fixed in a horizontal pressure vessel 7. 8
A detailed diagram of this is shown in Figure 1. (a) shows a case where the filter frame 10 has a slurry supply port. The upper part of the filter plate 8 is shaped like a corrugated plate, and the concave portion thereof communicates with the filtrate discharge pipe 9.

A filter medium 11 is laid on the top of the filter plate 8, and the filter frame 10 and support part 1 are
2. As the filter medium 11, known filter paper, filter cloth, etc. can be used. A deformable water-impermeable membrane 13 is provided on the upper part of the filter frame 10 and fixed with a pressing plate 14, and the filter plate 8, the filter frame 1O, and the water-impermeable membrane 13 form a reducing wheel 5.

As the deformable water-impermeable membrane, a natural or synthetic elastic body that can be deformed by the pressure of the material to be filtered such as slurry, such as water-impermeable rubber, rubber cloth, etc., can be used. One or a plurality of cuts 15 are provided in the taste frame 10 to serve as a slurry supply port into the reducing wheel 5. Cut 15
For this purpose, add equipment to prevent movement of the cake produced at this location, such as wire mesh, gutter width, etc.

FIG. 4(b) shows a case where the water-impermeable membrane 13 is provided with a slurry supply port. In this case, the filter frame 10 is not provided with a cut, but instead one or more holes 16 are provided in the water-impermeable membrane 13. This is the only point that differs from Figure (a).

(Function) In the case of FIG. 4(a), the slurry supplied to the pressure vessel 7 passes through the cut 15 provided in the filter frame 10 and
b) In the case shown, it is fed into the reducing wheel 5 via a hole 16 provided in the water-impermeable membrane 13. After supplying the slurry, when filtration pressure is applied to the pressure vessel 7, the filter cake is first transferred to the filter medium 1.
Grows parallel to one plane. Filtration progresses and cake decreases by 5
Once the slurry is filled with water, a filter cake is formed only in the vicinity of the slurry supply port 1, and the effective filtration area changes rapidly and decreases. As a result, the flow of the filtrate changes,
The hydraulic pressure distribution of the cake in the reducing wheel 5 changes, and the cake compression force increases by the amount of the change, thereby consolidating the cake.

At the same time, the water-impermeable membrane 13 is gradually depressed downward under the influence of the slurry pressure acting on the water-impermeable membrane 13, thereby promoting consolidation and dewatering of the filter cake.

(Effects) According to Zero Development, the mechanism of the filtration device is simple, so operation and maintenance are easy. Further, according to the present invention,
It is possible to obtain a cake with approximately the same low moisture content as when using conventional pressing equipment. For example, when clean water sludge (1ffi fraction of solids in slurry S = 0.08) is used as a sample, the water content of the product cake obtained by a normal filtration operation is about 75% on a weight basis. In contrast, in the present invention, it is possible to reduce this moisture content to about 50%, which is almost comparable to the value obtained by conventional pressing operations.

In Figure 5, water sludge is used as a sample in which the reciprocal of the filtration rate dθ/dv and the side volume Δh of the unfavorable aqueous membrane are plotted against the filtrate volume V.
Case 1 is shown. During the consolidation period, the value of dθ/dv increases rapidly, but the cake thickness also decreases rapidly.
The water-impermeable membrane was significantly depressed downward, indicating that consolidation dehydration of the filter cake was progressing.

Therefore, according to the present invention, in addition to being expected to have the same level of performance as a compression device, operation and maintenance are simple, there are fewer failures, and it is extremely advantageous in practice compared to conventional compression devices. be.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a filter plate of a filtration and pressing device according to an embodiment of the present invention, where (a) the filter frame has a slurry supply port, and (b) the slurry supply port is provided in the water-impermeable membrane. This is the case when the ! Fig. 2 is a partially cutaway perspective view showing a leaf filter, which is a type of conventional filtration device, Fig. 3 is a partially cutaway side view showing a filter press, which is a type of conventional filtration device, and Fig. 4 is a booklet. It is a schematic diagram of the filtration press apparatus by the invention Example, (a) figure is a horizontal type case, (b) figure is a vertical type case. FIG. 5 shows the reciprocal of the filtration rate dθ/dv (○ mark) and the displacement Δ of the water-impermeable membrane for the filtrate 11v in the example of the present invention.
It is a graph showing h (Δ mark). 1...Slurry supply port 2...Filter leaf 3...Filtrate discharge port 4...Cake/drain discharge port 5...Filter chamber 6...Tightening device. 7... Pressure vessel 8... Filter plate 9... Filtrate discharge pipe 1o... Filter frame 11... Filter medium
12... Support part 13... Water impermeable membrane
14... Pressing plate 15... Cut end
16-...hole. Figure 1 (a) (b) Figure 4 (a) (b) The amount of coal per unit of Figure 5 (m). Display of 1982 Patent Application No. 167744 2 Name of the invention Filtration and squeezing device 3 Relationship with the case Patent applicant Nagoya University Nagami 7 Contents of the amendment (as attached) 16 Specification page 6 Correct "Filtrate 2" in line 10 to "filter leaf 2." 2. Correct "Fig. 4" in line 9 of page 6 to "Fig. 1" and "Fig. 1" in line 16 of the same page. 8. Correct ``Slurry supply C] IJ in line 2 of page 7 to ``Cut 15 and hole 16J'' in line 6 of the same page to ``Figure 1''. ” is corrected to ``consolidate.'' ``Side position'' in line i of page 8 of the same page is corrected to ``displacement,'' and ``point-stitched sample'' in lines 4-5 of the same page is corrected. 5. Corrected "Tightening is a device." on page 9, line 18 of the same page to "tightening is a device." 1. Corrected "tightening is a device." 1. is corrected to "hole".

Claims (1)

[Claims] 1. A means for changing the flow of the filtrate by rapidly reducing the effective filtration area after the filter chamber is filled with the filtrate cake produced by the filtration operation of the material to be filtered, or during the progress of filtration, and a means for changing the flow of the filtrate by the pressure of the material to be filtered. 1. A filtration press which is equipped with a water-impermeable membrane and which produces compression dewatering of the resulting filtration cake.