JPS6013592Y2 - Equipment for dewatering sludge-like materials - Google Patents

Description

[Detailed description of the invention] The invention relates to an apparatus for dewatering sludge-like materials, in particular sewage sludge or mineral beneficiation sludge, in which at least two parts of the sludge or presscake, which are to be treated in part in the working state, are covered from both sides and are guided around a drum. It has two mesh belts.

A method of this kind and a device suitable for it are described in the German Patent Publication No. 1960787 Filterpre,
The mesh belt is led in part around individual drums, between which the dewatering sludge is treated.

In this case, it became clear that the dehydration capacity was insufficient.

Apparatuses with similar belt guidance according to US Pat. No. 2,111,72 ()@ or West German Pat.

This drawback is due in particular to the fact that the sludge to be treated during the dewatering process is not sufficiently sand-bedded.

The object of the present invention is to avoid the above-mentioned drawbacks and to obtain such a device which can provide a high dewatering capacity as well as a high space utilization rate.

The ratio of the effective belt length to the total length of the device is used as the space utilization factor, and this ratio is 50% for currently commonly used devices or dehydrators.
% or less, which is often of great significance due to the insufficient footprint.

This purpose is achieved by means of the invention, in which the mesh belt is placed in the opposite direction of rotation to the drum it surrounds first (partially surrounding one drum, and the outer mesh belt of the first drum is placed on the wall of the next drum). The invention is solved by an apparatus for dewatering sludge-like materials, which is characterized in that the mesh belt is supported approximately S-shaped in longitudinal section on a drum which is in the form of a dewatering drum.

The walls of the dewatering drum consist of grooved or perforated copper plates or tubes parallel to the drum axis, so that the filtrate coming from the sludge or press cake can enter inside the drum and be drawn off from there.

According to the invention, this dewatering drum has two (many if the invention features a number of drums arranged one behind the other) press zones in the area of its periphery in contact with the belt; Due to the S-shaped guide of the belt, stress is applied to the cake structure in between, and the pores in the sludge containing the water are torn, and the water contained therein flows out.

The sludge according to the invention passes through one or several filtration or pre-dewatering zones on one mesh belt and then transfers to another mesh belt while simultaneously being mixed under the action of shear forces as a heterogeneous press cake. , then passed through the pre-pressing zone between approximately parallel and especially linearly guided mesh belts, at the end of which the sludge transfers to the first drum of the dewatering drum, the sludge being subjected to a pulsating pressure. and continuous shear forces, which are applied in the opposite direction after the sludge or presscake has completely relaxed after leaving the first dewatering drum.

The press cake on the second dewatering drum then passes through a press zone curved in the opposite direction.

Said pulsating compressive force is produced by the press cake passing at a constant speed between the mesh belts and under the press rolls or compaction rolls provided on the wall of the dewatering drum according to another feature of the invention. This is achieved by selecting the compacting force to increase in particular in the feed direction.

It has proven particularly desirable in this case to choose the winding angle of the mesh belt, which clearly determines the length of the press zone, to be greater than 180' and to install press rolls or planetary rolls at least in this range of the drum periphery.

The longer the press zone is selected, the stronger the shearing force generated by the belt rotating around the dewatering drum will act on the press cake.

Because the outer belt has to take a longer path than the inner belt, for equal belt speeds, the outer belt lags behind the inner belt by a radius difference, or a length equal to the product of cake thickness and wrap angle.

Delays in the outer belt cause misalignment within the cake.

This tissue displacement forces a very large amount of liquid out of the cake.

It goes without saying that the stress direction reversal between the dewatering drums mentioned above significantly increases this effect.

It is within the scope of the invention to control the pressure of the planetary rolls both individually and in large groups; this can be done by means of a tensioning member, for example a rope, which is attached to a drum stand or other location. Contacting the supported lever arm of the present invention.

A rope tensioned in the circumferential direction of the dewatering roll contacts, for example, an adjustable cam of the lever arm; by tensioning the rope, the component of the force of the rope in the direction perpendicular to the lever arm is magnified, with the pressing force of the planetary roll being It changes depending on the support point of the lever arm and the adjustment of the cam.

According to another feature of the invention, the pressure of the compacting rolls, which are arranged offset from one another in the feed direction, is increased and/or equalized by pressure plates covering a large number of the rolls.

Such pressure plates are placed on both sides of a mesh belt running approximately parallel to the front press zone and are optionally pressed together against the belt, thereby making it possible to additionally control the roll pressure.

A compression roll is a continuously rotating compression belt, etc.
Advantageously, they are formed as parts and are connected to each other by a chain.

In this case, it depends on the purpose of use of the device whether the compression belt is driven or whether it is interlocked by friction using a mesh belt.

A compression belt or the like can also be used to carry a mesh belt that is not driven.

In other cases, the control of the belt takes place in a known manner via guide rolls or, in the present case, a dewatering drum.

In a particularly advantageous embodiment of the device according to the invention, a mesh belt runs approximately horizontally from the feed chute or a corresponding device to the guide roll, forming a filtration or pre-dewatering zone in this section.

From the guide roll this mesh belt runs in the opposite direction through the front press zone together with a second mesh belt which is turned around by another guide roll, at the end of which the two mesh belts together pass into the first dewatering drum. reach

This dewatering drum is wound with a wrapping angle of 220-240° according to the invention.

The mesh belt from the first dewatering drum is wound with a large wrap angle onto another dewatering drum which is arranged approximately horizontally with respect to the first drum.

After leaving the second dewatering drum, the last in the case of multiple dewatering drums, the treated presscake is dumped and each mesh belt is separated and returned to the filtration or pre-pressing zone.

During this process, it is advantageous for the mesh belt to push against a part of the planetary roll from the side opposite the drum, increasing its compression pressure.

A filter press of this type with two dewatering drums has an effective belt length of approximately 16 m, with a drum diameter of in., without an overall machine length of more than 2.59 m.

The so-called space utilization of more than 70% far exceeds the values of known comparable filter presses or similar devices.

Next, the present invention will be explained with reference to the drawings.

Filter press R consists of two large dewatering drums 1 or 2
The mesh belts 4, 5, which are guided partly parallel to each other onto this drum, fit tightly in an S-shape in elevation over a wrapping angle rrL (for example 235°) or n (for example 285°). .

In the feeding direction t of the sludge cake Q to be treated, the first mesh belt 4 moves the sludge cake Q in the feeding direction 1 on the support roll.
The cake Q passes through a filtration zone D1 for pre-dewatering, and the liquid from the cake Q drips through the mesh of the upper belt 4° into the collection toy 7.

The sludge cake Q, which has been previously dewatered by the guide roller 8 of the mesh belt 4, falls onto the upper part of the second mesh belt 5, which is approximately in contact with the lower surface of the guide roll 8, and is turned over and mixed therewith.

Between the lower section 4U of the first mesh belt 4 and the upper section 5° of the second mesh belt 5, the sludge cake Q is conveyed through the front press zone D3, and presses are arranged in a staggered manner on both sides of the belts 4u and 5o. Roll 9 squeezes this cake.

The two rows of compacting rolls 9 are compressed by a belt 4. ,5. pressed against.

The deflection of the belt caused by the compaction roll 9 is not shown for reasons of simplicity.

After the two mesh belts 4 and 5 leave the front press zone D3, they pass around the dehydration drum 1 together with the press cake Q between them in the rotational direction of i□, and this angle m is the width of the mesh belt. The main press zone D is guided between the belt 4, 5 quad drum wall 11 and the planetary roll 40 located outside the drum wall 11.
Determine the length of 5.

The drum wall 11 is made of a grooved steel plate, a perforated plate, or, as shown in FIG. reach

Although the tube 41 is not shown, it is laterally perforated so that the filtrate, etc. that has collected in the lower region U of the drum can enter the interior of the tube and be discharged from its end face.

The planet roll 40 is drawn against the drum wall 11 by the action of the force storage device 42 .

This is done for each planetary roll 40 separately or for a large group of rolls as a whole.

The planet roll 40 is rotatably supported by a press stan 45 indicated by a dotted line 46 by a 7-me 44.

This arm 44 is equipped with a slidable cam 47 that supports a tension rope 48, the tension of which can be adjusted with a force storage device 42, which in this case is designed as a winch.

This pressing device 42-48 utilizes the lever principle and the pressing of the individual planetary rolls 40 allows individual adjustment of the force.

By tensioning the rope 48, the component of the rope's force in the direction perpendicular to the arm 44 increases, and when the planetary roll 40 is pressed, the force is increased between the fulcrum 46 of the arm 44 and each cam 47 supporting the rope 48. Varies depending on the length of the lever arm.

The pressing force is additionally increased by the tension of the belt return section 4e or 5e in the region where the entire planetary roll 40 or individual planetary rolls 40□ are utilized for belt redirection.

At the position of the mesh belt 49.5 away from the drum 1 or the press zone D5, which is determined by the lower leg 50 of the wrapping angle m, until then the radius r of the dewatering drum 1 is removed between the mesh belt 4°5. The press cake Q, which had been curved, is suddenly stretched, and the area that was initially on the inside of the cake is stretched, and the area that was initially on the outside is compressed.

In this case, the structure of the press cake Q is relaxed and prepared for a new pressing process in the same way as it was under the influence of gravity during the reversal from the filtration zone D1 to the pre-press zone D3.

On reaching the wall 11 of the next dewatering drum 2 at the end of the relatively low pressure zone F, the relaxed press cake Q is bent one more degree in the opposite direction, while at the same time reducing the belt tension and the first planetary roll 40a. The effect is further enhanced by the press pressure applied.

This process allows even more liquid to be forced out of the press cake Q, which now has a completely different texture, as it passes around this dewatering drum 2, which would not have been possible at all without the above-mentioned reversal.

The continuous shearing action by the advancing inner belt 4 sustainably supports the dewatering process.

The dewatering drums 1, 2 may rotate at synchronous speeds or at least slightly different speeds, so that drives with gears of different reduction ratios are used.

The mesh belts 4 and 5 are rolls 407. After leaving the dewatering drum 2 in the region of , the mesh belts 4, 5 are guided together with the dewatered press cake 0 via a common guide roll 150 to smaller individual rolls 52.

Planetary rolls 5 specific to guide rolls 150 located at the vertices of an imaginary triangle with equal legs passing through the drum axes encompassing an angle ν of approximately 35° with the joining line of the drum axes shown in FIG.
1 is placed.

Further, a part of the planetary roll 40 of the adjacent dewatering roll 1 is in contact with the mesh belt 4°t5a that runs away.

The two rolls 52 are placed apart from each other and form a gap 53 between the belts 4, 5 for dispensing the press cake 0.

From the gap 53, the return section 4e or 5e of the belt first passes through the planetary roll 40 and then returns from the belt cleaning device 56 via the upper guide roll 55 to the filtration zone D or pre-pressing zone D3.

A special embodiment of the front press zone D3 is shown in FIG.

In this case, the press roll 9u below the belt 4u and 58 parts
The upper press roll 9° also forms a row of rolls rotating endlessly in the direction S of the arrow by means of a chain 61 connected to a roll support shaft 60, like a flexible cage of needle bearings.

The pressing roll 9 can be driven by frictional contact with the mesh belts 4, 5.

The pressing roll 9 is connected to the mesh belt 4 in the front press zone D3.
Pushed to the inside of 5.

A pressure plate P is placed on the opposite side of the belt across the diameter of the pressure roll 9.
□ or P2 contacts the roll 9.

When the chain 61 is pulled through its chain sprockets 63, 64 in the running direction i of the mesh belts 4, 5, the compaction roll 9 rolls on the fixed pressure plate P.

The circumferential speed of the opposite roll is twice the running speed of the chain 61.

Since the compaction roll 9 is not loaded perpendicularly to its axis by bending stresses, high pressures can be transmitted by the comparatively thin and light compaction roll 9.

The bending stress is absorbed by the pressure plate P above it.

Since the pressure plates P are spring-pulled together at 66, no force needs to be transferred from an external support structure.

Especially if the belt structure is light, chain sprocket 63
．． 64 can be driven, in which case the mesh drums 4, 5 are driven in the direction i via the compaction roll train 62.

The mesh belts 4, 5 are now driven by guide rollers 8,
50, 55 or one of the dewatering drums.

Since strong stresses occur in the area where the driving force is transmitted to the respective belts 4, 5, the drive is carried out by a large number of rolls 9 in the area where the force is actually required for pressure transmission, i.e. the mesh belts 4, 5. is not pulled through a large number of nip by one of the drive drums 1.2.50.55, but there is a transmission of a force which acts on each nip in accordance with the pressure prevailing therein, and this force is large. Evenly distributed over the surface.

By selecting various diameters d and axial distances f of the upper and lower press rolls 9, the mesh belt surface between which the press cake Q is sandwiched can be guided into various waveforms.

Further, upper and lower roll rows 62. Alternatively, the relative motion due to the speed difference between the two can be superimposed.

In the case of embodiment R1 shown in FIG. 4, the filtration zone D□ is missing and the sludge cake Q is fed directly to the pre-pressing zone D3 located at the bottom of the dewatering drum 1°2.

The compaction roll 9 is loaded by a pressure plate P which is elastically supported on the collecting toy 7 .

The sludge cake Q reaches the first dewatering drum from the front press zone D3.

Here, cake Q passes through press zone 8 and is then conveyed to press zone D7.

From here the belt 4 conveys the compacted cake Q to a guide roll 90 provided with a discharge chute 91.

After passing through a guide roll 90, this belt 4 passes through a cleaning zone 56 which has a collection toy 93 formed by two rolls 92 and the belt 4, and further passes through another guide roll 55, 8.
Return to previous press zone D3.

The other belt 5 passes the dewatering drum 1.3 and the planetary roll 4
Immediately after 0 or via other guide rolls, it leaves the lower belt 4, passes through the cleaning section 56, and returns to the front press zone D3.

In the cleaning section 56, a guide plate 94 collects the cleaning water and discharges ice through a conduit 95.

In order to enable pre-dewatering also in this example R□, another mesh, not shown, can be placed in front of the feeding position.

Extensive experiments have shown that the mesh belt press according to the invention has a significantly better dewatering effect than the belt press of conventional construction.

For example, in the case of living sludge, the solid content in the press cake is
It was possible to increase by ~10%.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a press with two dewatering drums;
FIG. 2 is a detailed view of a portion of FIG. 1, and FIG. 3 is a longitudinal sectional view showing another embodiment of the front press section. FIG. 4 is a longitudinal sectional view showing another embodiment of the press. 1.2...Dehydration drum, 4,5...Mesh belt, Dl...Filtration zone, D3...
...Front press zone, ['', -D7...Press zone.

Claims (1)

[Scope of utility model registration request] In an apparatus for dewatering sludge-like material, having at least two mesh belts which are guided around a drum and which cover the sludge or press cake to be treated on both sides and together form a press zone, the mesh belts 4, 5 are first partially surrounding at least one drum placed in the opposite direction of rotation to the enclosing drum 1 and with the outer mesh belt of the first drum touching the wall 11 of the next drum, the mesh belt 4.5 surrounding the dewatering drum. Apparatus for dewatering sludge-like materials, characterized in that the drums 1.degree.