NL8801343A - PRESS FOR THE CHARGE OF COMPRESSING OF PRESENT AND CONSTITUENTS OF A LIQUID AND / OR GASEOUS MEDIUM CONTAINING IN THE CONTAINMENT OF A LIQUID. - Google Patents

Description

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T-l / Klöckner-Humboldt-Deutz AG

PRESS FOR THE CHARGED COMPRESSION OF PONDS PRESENT IN THE FORM OF A LIQUID AND COMPONENTS OF A LIQUID AND / OR GASEOUS MEDIUM

The invention relates to a press for batch-wise compression of bulk solids and constituents of a liquid and / or gaseous medium containing particles / in particular for dewatering of medium-permeable layer-encapsulated suspension slip pallets / with at least one pressing element / comprising two opposing and in cooperation with an annular hollow body / the so-called jacket ring / movable with respect to each other and 10 pressing dies forming between them in a pressing space / wherein this pressing space is displaced by displacing the sleeve ring at least one of the press stamps can be opened or closed.

Large quantities of waste / in particular sludge from sewage treatment plants / industrial sludge as well as, for example, slip from rivers and / or port / nowadays have to be disposed of and / or dewatered as much as possible under increasingly stricter legal regulations and obligations.

Extensive dewatering of such sludge-like waste materials is necessary / in order to meet more stringent requirements with regard to the solid content as well as the soil mechanical stability for depositing.

In the case of shortcomings of suitable methods, attempts are often made to achieve the solids content and the soil mechanical stability of the waste materials by admixing dry additives such as dust or ash. The known method has the drawback that, in addition to increased costs for obtaining and transporting the additives, it also takes up additional storage capacity; therefore it is in its. 8801343 «* -2-completely unsatisfactory.

To solve these problems, a new sludge dewatering method is proposed / according to which pallets are first formed from a partially dehydrated sludge mass, after which they are coated with a drainage material in the form of a dry powder, after which the thus prepared pallets with the medium-permeable draina cladding in separate bulk batches are compressed in a press. Liquid is thereby squeezed out and a largely dewatered / compact briquette is formed.

The achievable progress of a considerably better dewatering of the mud pallets can hereby be traced back to the fact that the liquid to be squeezed out from the medium-permeable drainage layer surrounding the individual molded part, always only the way up to the nearest drainage layer and so on / within the outlet. press to be charged. Hereby a considerable reduction of the mass of the original material takes place before this is dumped / as a result of an optimal dewatering. This method is therefore very efficient and at the same time economical.

A further improvement of the said process is known from European patent 0 092 146. This is distinguished in that the dewaterable material for the shaping into pallets is pre-dehydrated to a water content of less than 85 weight percent and the pallets using a distribution method using a distribution palletizing machine without disturbance of the internal sludge structure and, after coating with the draining material, are batch-loaded in two compression steps, first at a relatively low pressing pressure and then at a relatively high pressing pressure in a press.

From the "Enzyklopadie der Technischeen Chemie" of 35 Ullmann / fourth edition / volume 2, process technology I (basic operations) / Verlag Chemie / Weinheim 1972 / pages 199 to 203 / methods and presses for squeezing liquids from solids are known . In it, for example

a

-3- i added on page 199 left column: "In order to separate the liquids present in hollow spaces / pores and capillaries of moist substances, squeezing can also be considered in addition to filtration.

Squeezing is of economic importance / since the energy costs related to the amount of liquid to be removed are generally lower than in the filtration. "10 and further:" As a rule, it is advantageous not to allow compression with compressed pistons to take place too quickly / so that the liquid does not push up and under certain circumstances blocks the channels necessary for the discharge 15. A slow pressure increase also has the advantage that the liquid flowing away does not entrain solid particles / so that the risk of clogging is reduced and clear liquid is obtained. "20

The press devices listed in the above-mentioned literature reference / suitable for squeezing out liquid mention on page 201 / left column / last paragraph stove presses / which are structurally located between the storey and filter presses and also cockpit / ring or box presses are called. With these press boxes / in which the press is located / when pressing together like a box. The press body / called press pot or stove / is a cylindrical box / with a movable and a fixed bottom. The movable bottom (the suction surface) of one box forms the fixed bottom of the adjacent / on which the perforated plate and the filter cloth lie / which can be removed with a ring for filling and emptying.

Presses of the type mentioned have been known for a very long time. For example, German Patent 290,718 of November 18, 1913 describes a hydraulic cocoa press of the present kind.

This comprises an annular hollow body and press dies 8 0 o A 7 '- Ύ 0 V' -, ·: ν 'm -4- * elements formed in accordance with the known pot presses and is characterized in that the press dies have a length such that after pressing has been carried out and securing the hollow body can further expel the pressing angle from the hollow body.

Cocoa pot presses of the same type as this known device are further shown, for example, in German Auslegeschrift 125,641 / German Patent 2,557,056 or German Patent Application 2,821,316.

As a characteristic feature of all these known pot presses in horizontal arrangement, these feed devices for pasty or liquid material to be pressed / which are fed through filling lines with pumps, for example in accordance with DE-AS 1,251,641, figure 2, through filling valves in the pressing chambers 15. brought. The annular press pots mainly have only the width of the press gap between the press dies. In order to seal the press spaces with respect to the press material, large closing forces and separate seals are required for each individual press gap. For example, the sealing of the press spaces of the device according to German Patent No. 290,718, as seen in Figure 3, is performed by screwing a pot-shaped, annular body 12 against a press-stamping body 9 with the interposition of a seal 19, each with two diametrically opposed spindles 17 with nuts 18, via a manually driven screw drive 20, 21, 22.

On the one hand, the effort required for this is very great and frequent renewal of the seal is necessary, and on the other hand none of the aforementioned pot presses are both from the older state of the art (1913) and also from the new state of the art. (1977) suitable for batch loading of a single pallet of bulk material with fast and functionally reliable work cycles.

Indeed, very essential for the successful implementation of the sludge dewatering process is the extremely careful treatment of the bulk material consisting of separate pallets covered with enveloping material; in particular with batch loading of the bale chambers. This must be insured; that when filling the baling chamber and during subsequent pressing; the effect of shearing forces 5 on the pallets in the bulk material is avoided; because the sensitive drainage layers are partially or completely disturbed by shearing or lubricating effects and the dewatering is considerably adversely affected.

The object of the present invention is to design a press 10 of the type mentioned in the preamble such that it is particularly suitable for dewatering sludge pallets covered with drainage material and present in the form of a bulk material. The press must be provided with means for careful yet rapid filling when a batch of bulk material is supplied; whereby an even and complete filling of the baling space is ensured; furthermore, a segregation of the grain size distribution in the bulk material is avoided and, moreover, it is ensured that no shearing forces occur during loading or during pressing. In doing so, the greatest possible performance or the greatest possible press capacity must be achieved by an uncomplicated and economical design of the individual elements of the press.

This object is achieved with a press for batchwise compression of particles present in the form of a bulk material and constituents of a liquid and / or gaseous medium containing the invention according to the preamble of claim 1, in that the jacket ring is designed is like a sliding tube with at least two axial regions; in which the two aligned press dies are continuously sealed.

The advantage of this embodiment lies in its uncomplicated construction in particular; that the 35 punches without sealing elements provide sealed press spaces in conjunction with the sliding tube; and that they are suitable for the problem-free supply of a bulk material charge without detriment to the bulk material during the supplying process. Also for filling the press space with sewage sludge pallets, a certain amount of material does not need to be weighed or supplemented beforehand, because a determination of the supplied quantity of a batch 5 is simply done by adjusting the width of the press space in the gap between the press dies / automatically occurs. In addition, a constant density of the deposit is automatically obtained. Furthermore, since the crevice of the pressing space is relatively narrow relative to the diameter, a mixing according to the grain size is / are avoided when the pallets are supplied.

The casing ring widened by the invention into the sliding tube, in which the two mutually opposite pressing dies are continuously sealed, does have a relatively greater actual length than the annular narrow hollow bodies of the known pot presses. However, the sliding tube is essentially a smooth piece of tube with one-piece tube parts of a uniform size. This advantageously avoids the use of cumbersome sealing or connecting means / complicated and / or complex shapes such as undercuts of the pressing members, etc., which considerably simplifies the manufacture, assembly and operation as a whole and the applicability of the press is significantly improved.

According to an embodiment, the sliding tube is provided with openings in the different parts, these being arranged in such a way that in a first position the filling space of the pressing space is filled in different positions of the sliding tube relative to the press space formed between the press dies with bulk material through the released feed opening in a second connecting position, enabling the batch to be compressed in a closed baling space, as well as finally in a third position, allowing the free discharge of the briquettes from the baling space through the discharge opening hereby released.

The sliding tube thereby has a kind of valve action, for example during filling, in the manner of sliding, whereby in one position of the sliding tube the filling opening is in free connection with the baling space / this baling space after sliding the sliding tube into the next position for the pressing operation is closed / and finally a further displacement of the sliding tube releases a discharge opening downwards.

As mentioned, this only requires a device for sliding the sliding tube in the separate positions relative to the press space formed between the press dies.

For this purpose, an effective embodiment provides that the supply opening in the sliding tube is arranged in one of the areas on one side of a closed central section intended for the formation of the closed press space and the discharge opening on the other side of the central section. on a lateral section intended for this purpose.

It will be understood that this device provides an optimum of efficiency with the greatest possible simplicity of the embodiment.

According to another embodiment, the supply opening in the sliding tube and the discharge opening are arranged opposite it at the top and bottom, respectively, and the discharge opening can be closed by a closing member when the press space is being filled.

In this embodiment, the length of the sliding tube 25 can be advantageously reduced by about 30%. On the other hand, the provision of a shut-off member for the discharge opening requires increased mechanical complexity.

In another embodiment of the press, the discharge of the pressed material from the press chamber can take place by means of an ejector penetrating through an ejection opening in the sliding tube / in the press room. There is an opening for introducing the ejector opposite the lower discharge opening / in the upper part of the sliding tube.

According to an embodiment, the working direction of the press dies is horizontal while the end faces of the press dies are vertical.

The end faces are thereby efficiently. 8 8 0 1? H -8- at least of one of the pairing press stamps which are paired together, constructed as a filter plate and stretched with a filter medium permeable for the medium to be squeezed out.

This advantageously achieves that the filtrate released on the filter surface does not have to be sucked off, but flows away under the influence of gravity. Thus, additional filtrate suction devices can be omitted.

According to a further embodiment, the ejector arranged for ejecting the pressed material can preferably be combined with a spraying device and this can be designed in such a way that the filter medium is cleaned without any problem by a cleaning liquid with suitable spraying arrangement.

15. For this purpose, the ejector designed as a spraying device can advantageously be guided parallel to the reverse stroke over a half spraying nozzle distance which is displaced parallel to the variable stroke.

This makes it possible to completely clean the entire filter surface 20 for only one forward and reverse stroke at a time.

In a preferred embodiment of the press, two or more similar press elements are arranged in a press one after the other, so that a number of batches are pressed out simultaneously. Thus, by combining the press elements into a multi-part press unit, the capacity of the press can be considerably increased.

It is further provided that individual pressing elements can be exchanged with similar elements or spacers without pressing function. This provides the possibility of carrying out necessary maintenance or repair work on individually exchangeable pressing elements / without the other pressing elements / which at that time do not require maintenance / having to be put out of operation.

In this way, the availability of the press is also largely maintained in the event of repairs or maintenance, thereby avoiding downtime or downtimes. 8 8 0 ff4 ύ -9.

In one embodiment it is further provided that the end face of a press punch is equipped with a press membrane which can be loaded from the rear with a pressure medium.

In this way, the force introduction into the material to be pressed is advantageously made more uniform by the design of an isobaric membrane surface. As a result, an action of shear forces on the material to be pressed 10 is avoided and an optimum pressing result is achieved.

Finally, in this embodiment, the pressing membrane on the side facing the material to be pressed for the discharge of filtrate can be ribbed and can be stretched with a filter medium.

The invention is shown in schematic drawings in a preferred embodiment, wherein the drawings may show further favorable details of the invention.

The drawings show in detail: FIG. 1 a press for dewatering by batch compression of bulk solids / partial cross-section;

Fig. 2 a press element of the press according to the invention in perspective view; FIG. 3 to 6 show a pressing element with different positions of the sliding tube relative to the pressing space; during filling of the baling chamber (fig. 3); before the start of the pressing operation (fig. 4); at the end of the pressing operation (fig. 5); upon ejection of the fully pressed-out pressing piece in fig. 6.

Fig. 1 shows a press according to the invention with at least two press elements 1 and 2, which are clamped between two end plates 3a, 3b by means of guide elements 4. Each pressing element 1, 2 comprises pairs of pressing stamps 14a, 14b arranged in pairs, which are aligned in a line in a sliding tube 6 covering this sealed and which are guided continuously sealed.

The sliding tube 6 is designed with at least two axial tube sections 21, 32, 22. Openings 7,8,9 are provided in these different sections 21/32/22. The opening 7 thereof is a filling opening arranged on the top side of the sliding tube 6 / in the tube section 21. Above this opening is a filling device 10. It is preferably dimensioned such that it can receive at least one batch. The central tube portion 32 adjacent to it is closed all round, and thus has no openings, and serves in the suitable position (Fig. 5) for closing off the press space 12 during the compression of a batch of press material.

In addition, the pipe section 22 is provided with a bottom discharge opening 8. This discharge opening 8 on the underside of the sliding tube 6 preferably occupies the half bottom circumference of the sliding tube 6 and the cross-section of the opening 15 thus corresponds to the cross-section of the molded piece 27. This enables unhindered drainage. Diametrically opposite this discharge opening 8 at the top of the sliding tube 6 is an ejection opening 9 through which the ejector 23 arranged for ejecting the pressing piece 27 from the pressing chamber 12 can be inserted.

Since, according to the invention, as can be seen from Figs. 1 to 6, the pressing dies 14a, 14b are guided in sealed position within the sliding tube 6 in every operating position, there are no special sealing elements and closing members or closing forces necessary. Instead, the invention provides an extremely straightforward and robust press unit.

As can be seen in Fig. 2, the filling opening 7 can be provided with a very large opening cross section by the sliding tube 6, so that the filling operation for the bulk material can be carried out unhindered, quickly and without problems. Since the sliding tube 6 acts as a closing slide when the filling operation is shown, as shown in the intermediate position in Fig. 4, when the pressing position is shifted, filling the baling space with a batch is straightforward and problem-free without prior gravimetric or volumetric dosing device .

.8801 '-; -11-

The sliding tube 6 with the filling device 10 is moved by a hydraulic unit 11 into the different positions, i.e. in the filling, pressing or discharge position. In the two end positions on the left or right, the sliding tube 6 always rests against the surfaces of the flanges 17a, 17b.

The press chamber 12 is formed between a pairwise arrangement of end faces 13a, 13b of the press dies 14a, 14b and the wall of the sliding tube 6 which guides them in a sealing manner. The end faces 13a, 13b of the press dies 14a, 14b are provided with filter plates and these are stretched in known manner with a medium-permeable filter medium 15a, 15b.

Optionally, however, one of the end faces 13 can also comprise a pressing membrane 16, which can be loaded with a pressure medium at its rear side, in order to carry out the force introduction into the pressing piece 27 during pressing. In this case, an isobaric pressing surface is created by pressure equality over the entire surface of the pressing membrane 16, ie the pressing pressure across the surface of the press material is the same everywhere. Hereby, the occurrence of shear stresses in the bulk material charge to be squeezed is effectively prevented and an optimum pressing result is achieved.

The press dies 14a, 14b each have guide flanges 17a, 17b at their ends, which are guided movably with guide bores 18 along the guide elements 4a, 4b. The guiding elements 4 themselves are screwed back into the end plates 3a, 3b and transfer the reaction forces of the pressing operation. Guides can furthermore be arranged on the sliding tube 6, which co-act with the guides 4a, 4b.

The pressing pressure is applied to the pressing elements (1, 2, etc.) or to the pressing dies 14a, 14b thereof, because a working piston 19 in a working cylinder 20 is pressed against a guide flange 17 of the pressing die 14b in a working cylinder 20 by a pressure fluid frozen in the working cylinder 20. the pressing element 1 is pressed.

.8801345 -12-

A displacement unit arranged on each flange 17a serves to move the sliding tube 6 in the different positions according to Figs. 3 to 6; preferably a hydraulic unit 11 / which comprises a hydraulic piston 34 with piston rod 24 and a piston rod support 25 attached to the slide tube / as shown in Fig. 2.

The pressing element 1 shown in perspective view in Fig. 2 as an example is delimited on both sides by guide flanges 17a / 17b. The associated pressing dies 14a / 14b and the stamping surfaces 13a / 13b thereof together with the closed jacket ring 5 form the part 32 of the sliding tube 6 / the pressing space 12.

The sliding tube 6 has on one part 21 / the filling side / the filling opening 7 with a relatively large surface area and 15 on the other part 22 / the discharge side / above the discharge opening 9 for inserting the ejector 23 and diametrically opposite thereto / on the underside the discharge opening 8 /, which is not visible obliquely from above / in fig. 2 according to the perspective representation, but is shown in cross section in fig. 1 as well as in fig. 3 to 6. Between them lies the closed central section 32 for closing off the baling space 12.

As is clear from Fig. 2, the slide tube 6 is moved by the hydraulic unit 11 / whose cylinder 24 is connected to the guide flange 17a and the piston rod 24 thereof is connected to a holder 25 attached to the slide tube 6. 17a / 17b and therewith the press dies 14a; 14b of the pressing element 1 are mounted in the guide elements 4.

Figures 3 to 6 successively schematically show on a larger scale the different operating positions of the sliding tube 6 on the press dies 14 relative to the press space 12 during one pressing cycle.

Fig. 3 shows the position of the sliding tube 6 when filling. This is set by the displacement unit 11 such that the filling opening 7 is in open communication with the pressing space 12. A batch of the bulk material to be compressed automatically flows from the filling device 10 into the pressing space 12. In this position, the discharge opening 9 in the upper part of the sliding tube 6 and at the same time the underlying waste opening 8 is covered and thus closed by the press die 14a on the left side of the pressing element 1.

Fig. 4 shows an intermediate position of the sliding tube 6 in a movement phase in which the pressing space 12 is closed by the closed jacket ring 5, the middle part 32 of the sliding tube 6, after filling.

The filling opening 7, in conjunction with the press punch 14 on the right-hand side, is closed automatically in the manner of a sliding closure, without the need for a separate closing element. As a result, a complete and uniform filling of the pressing space 15 12 without any shearing or lubricating effect seems advantageously to be referred to the pallets, without a batch having previously been volumetrically or gravimetrically dosed.

In Fig. 5, the second position in the cycle is shown, wherein an all-round casing ring 5, corresponding to the tube section 32 of the sliding tube 6, keeps the pressing space 12 closed for carrying out the pressing operation. The pallets to be subjected to the pressing operation are then exposed to a stepped increased pressing pressure and the pressed-out filtrate 26 is transferred to the filter plates 15a, 15b provided on the end faces 13a, 13b. extracted from the outside or collected by channels or hollow spaces respectively and discharged from there (not shown).

Fig. 6 shows the third position in the cycle in which the sliding tube 6 on the tube section 22 with the discharge opening 9 at the top and the discharge opening 8 at the bottom is in open communication with the open press space 12. The filling opening 7 is through the cylinder jacket surface of the press punch 14b closed from the inside. The ejector 23 is guided into the ejection opening 9, which ejects the pressing piece 27 downwardly from the pressing space 12 through the discharge opening 8.

The sprayer 28 is mounted in the ejector 23. 8 80 1-r-14 -14- which is provided with spray nozzles 29. The spray device 28 and the conductive nozzle 23 respectively describe a half nozzle spacing parallel to the return stroke relative to the forward stroke. shifted track 30.

Thus, if necessary, the ejector 23, after removing the pressing piece 27, can function as a rinse aid for cleaning the filter media 15a; 15b are used. A suitable cleaning fluid under pressure is supplied to the spray nozzles 29 and the ejector 23 is guided in the unchanged position of the sliding tube 6 through the pressing space 12 and thereby moved back in a reverse stroke relative to the forward stroke over a correspondingly displaced path.

The working cycle of the press shown in Figs. 3 to 6 first ensures such a position of the sliding tube 6 according to Fig. 3, so that the filling device 10 is in open communication with the press space 12 via the filling opening 7, whereby the pallets of the bulk material to be compressed flowing in under gravity are completely and optimally filled. Subsequently, the sliding tube 6 is displaced by the hydraulic cylinder 34 of the displacement unit 11 over the pressing dies 14a / 14b, so that the pressing space is closed by the enveloping jacket ring 5 of the pipe section 32 (Fig. 4).

Then, with the aid of the pressure medium supplied in the working cylinder 20, the pressing pressure is applied through the working piston 19 by the pressing dies 14a / 14b to the batch of pallets to be compressed in the pressing space 12. During this press operation according to Fig. 5, the compressed batch, filtrate 26 is squeezed out and discharged from the press dies 14a / 14b through the press faces 14a / 13b spanned with filter medium 15 and discharged from the press.

The pressed piece 27 or 35 briquette produced by the pressing operation with considerably smaller volume and liquid content is ejected downwards through the discharge opening 8 from the pressing space 12 by means of the ejector 23.

. S 8 0 f 'a 3 -15-

Then the sliding tube 6 is moved back into the filling position of fig. 3 so that the next cycle can start.

. 8 b 0 1 3 Λ 5

Claims (13)

1. Press for batch-wise compression of bulk solids and constituents of a liquid and / or gaseous medium containing particles / in particular for dewatering of sewage sludge pallets coated with medium-permeable layer / with at least one pressing element / that two opposed and together with an annular hollow body comprise the so-called jacket ring / movable stamps which are movable relative to each other and between them in a press space / wherein this press space can be opened or closed by sliding the jacket ring over at least one of the press stamps are / characterized in that the sleeve ring (5) is designed as a sliding tube (6) with at least two axial parts (21/22/23) in which the two pressing stamps (14a / 14b) aligned in parallel are continuously sealed be guided. Press according to claim 1 / characterized in / that the sliding tube (6) is provided with openings (7/8/9) at the various parts (21/32/22), these 20 being arranged such that in successive operating positions of the sliding tube (6) relative to the press space (12) formed between the press dies (14a / 14b) in one of these positions filling the press space through an upper filling opening (7) with bulk material (31) ( 12) and in a connecting position enable the compression of the material in the closed press space (12) as well as finally in a subsequent position free discharge of the press piece (27) from the press space (12) through a lower discharge opening (8). . Press according to claims 1 and 2, characterized in that the filling opening (7) in the section (21) on one side of the middle section (32) intended for forming a closed press space (12) and the drain hole (8). $ 8017 * 3 -17- the other side of the middle section (32) is fitted to the designated section (22) of the slide tube (6). Press according to any one of claims 1 to 3 / characterized in / that the filling opening (7) in the sliding tube (6) and the discharge opening (3) lie opposite each other respectively. at the bottom of these and the discharge opening (8) can be closed by a closing member (33) when the baling space (12) is filled. Press according to any one of claims 1 to 4, characterized in that the discharge opening 8 is arranged on the underside opposite an opening (9) for an ejector (23) in the upper part of the sliding tube (6). Press according to any one of claims 1 to 5, characterized in that the working direction of the press dies (14a / 14b) is horizontal and the end faces (13a / 13b) thereof are vertical. Press according to one of Claims 1 to 6, characterized in that the end faces (13) are designed and stretched at least on one of the pairing presses (14a / 14b) associated in pairs, as a filter plate (15). with a medium permeable to filter out. 8. Press according to one of claims 1 to 1, characterized in that the ejector (23) is combined with a spraying device (23) and is designed such that the filter medium can be cleaned with a cleaning liquid. Press according to claim 8 / characterized in / that the ejector (23) designed as a spraying device (28) can be guided parallel to a displaced path (30) between the spraying nozzles at the return stroke relative to the forward stroke and a half distance between the spraying nozzles. turn into. Press according to any one of claims 1 to 8 / characterized in that two or more interchangeable press elements (1/2, etc.) are arranged in a horizontal row one behind the other and in the pressing direction by guide elements (4) which simultaneously transmit the reaction forces of the press. t8801Zk 3 -18- Press according to one of Claims 1 to 9, characterized in that the pressing elements (1/2, etc.) are individually exchangeable with similar pressing elements or spacers without a pressing function. Press according to any one of claims 1 to 10, characterized in that the end face (13) of a press punch (14) is equipped with a press membrane (16) which can be loaded with a pressure medium at the rear. Press according to any one of claims 1 to 11, characterized in that the pressing membrane (16) is ribbed on the side facing the pressing piece (27) for the filtrate discharge and is strung with a filter medium. 8801343