METHOD AND APPARATUS FOR TREATING SOLID, FLUID OR GASEOUS MATERIAL OF COMBINATIONS THEREOF, ESPECIALLY PULP SUSPENSIONS, ON A SCREEN OR FILTER SURFACE

Abstract: The invention relates to a method and a device for treating solid, liquid or gaseous substances or intermediate forms of these, in particular pulp suspensions, on a sieve or filter surface (213) by means of a treatment agent. The substance to be treated is continuously fed through parallel treatment conduits (230), and the treatment agent is taken from the treatment agent conduits (229) to the treatment conduits, from where the substance having passed through the sieve surface (213) is evacuated into the filtrate conduits (231). The holes (233) on the sieve surfaces are cleared for instance by vibrating or by a pressure exerted on the flow through the holes. In the invention, one wall of the treatment conduits (230) consists of the treatment agent conduit and the opposite wall of the treatment conduits (229) consists of the sieve surface (213) of the filtrate conduits (231). This arrangement is repeated such that on one side of each treatment conduit there is a treatment agent conduit, and on the opposite side of the treatment conduit there is a filtrate conduit, a treatment conduit being always provided on either side of a treatment agent conduit, and respectively a treatment conduit on either side of a filtrate conduit, treatment agent then passing into adjacent treatment conduits, from where the substance having passed through the sieve and filter surface passes into the adjacent filtrate conduit. The device for accomplishing the method comprises a container, which contains a compact set of conduits comprising juxtaposed treatment agent conduits (229), treatment conduits (230) and filtrate conduits (231).

Description: Method and apparatus for treating solid , fluid or gaseous material of combinations thereof , especially pulp suspensions , on a screen or filter surface . The invention relates to a method and a device for treating solid, liquid or gaseous substances or intermediate forms of these, specifically pulp suspensions, on a sieve or filter surface as set out in the preambles of claims 1 and 12. The method is particularly suitable for various treatments of cellulosic pulps, such as screening or washing subsequent to cellulosic pulp cooking step, and for pulp treatment in connection with bleaching. The method is also appropriate for washing sludge and precipitates, and for filtering even great volumes of water for instance after coarse screening and flotation. In all treatments of this kind, clearing the holes in the sieve and filter surfaces will cause a major problem. The holes are rapidly clogged unless they are cleared by special measures from time to time. Such clearing operations always increase process and equipment costs, given that they entail longer treatment and additional equipment, which are costly and extra energy-consuming. These are but a few examples of cost-increasing factors. Previously known in this field is for instance the method disclosed by FI patent specification 41712, in which waste water is filtered by means of three horizontally nested, cylindrical filtering elements. The filtering elements are vibrated with the aid of eccentric plates fitted on the central vibrating axis. In practical operation, the filtering elements will be clogged despite vibrating. A second embodiment of the same patent comprises a wash filter for sulphate pulp. The pulp to be washed is conducted upwards in a planear flow conduit and lye is separated from the pulp through the filtering element forming the conduit wall, and is recovered through outlets disposed in the various zones of the filtering element. The recovered caustic wash water is recycled in the washing process on the counter- flow principle. However, the pulp easily adheres to the sieve surfaces and what is more, packed by pressing, the pulp becomes more difficult to wash. The purpose of the present invention is to provide a process and a device of the type described above, requiring little space considering its capacity, having low energy consumption and flawless operation even with high-consistency pulps. The devices should also have low production costs. This has now been achieved with the process and the device of the invention, whose main characteristics are defined in the characterising clauses of claims 1 and 12. The basic idea of the invention is to fit a large number of filtering elements in a small space, and this has been accomplished by disposing the treatment agent conduit on the one side of the treatment conduit, such that treatment agent passes into the treatment conduit, and by disposing the filtrate conduit on the opposite side of the treatment conduit, such that the filtrate is discharged through the filtrate conduit. The conduits are mutually positioned such that a treatment agent conduit is on one side of each treatment conduit, and a filtrate conduit is on the opposite side of the treatment conduit, so that there will always be a treatment conduit on either side of the treatment agent conduit, and respectively a treatment conduit on either side of the filtrate conduit; with this arrangement, the treatment agent passes into the adjacent treatment conduits, from where the material passes through the sieve or filter surface and reaches the adjacent filtering conduit. The sieve or filter surfaces are cleared and the free flow for the material to be treated is maintained in a con- ventional manner. This idea is applicable to washing, screening, thickening and various chemical treatments of solid substances, sludges, suspensions and similar. The idea is also applicable to liquid and gas filtering, for instance for purifying waste water and flue gases. The idea is particularly well suitable for treating cellulosic pulps in various cellulose and paper production steps, such as for washing cellulosic pulp after the cooking step and in connection with bleaching. The container used in the treatment of cellulosic suspensions may be either open, or airtight and pressure-proof. The mixture of liquid and solid components to be treated is conducted into the upper part of the treatment container, from where it is allowed to drop, possibly under the effect of hydrostatic or pumping pressure, at a controlled rate, downwards through several vertical treatment conduits. The treat¬ ment conduits are provided with appropriate sieve surfaces. To prevent clogging of the treatment conduits and the sieve surfaces, the suspension is horizontally vibrated. In order to provide an appropriate pressure difference between the pulp feed end and the filtrate conduits, a difference between the liquid levels of the filtering spaces can be arranged in the front and rear spaces. It is generally preferable that the container is a cylindrical vertical container. Depending on the need, tens of sieve or filter cylinders may be vertically placed in this container around its axial line. When counter-current wash of cellulosic pulp is being concerned, cylindrical annular spaces are provided separately between these filtering cylinders for separated filtrate and wash liquor, and these spaces are divided by intermediate bottoms into compaitments on top of each other. Each treatment zone will thus have a wash liquor ring and a filtrate space ring of its own. These compartments are conventionally connected with their respective pumps on the counter-current principle. Water is used as a wash liquor in the lowermost zone, and separated lye fractions in the other zones. With a view to reduce fibre loss, the filtrate fraction of the uppermost zone is recycled into the pulp by pumping into the upper part of the container. According to the circumstances, the device may be provided with one or more vibrators. One vibrator including its motor may be placed in a conduit fitted in the middle of the treatment element, or its motor may be placed on top of the container cover. When several vibrators are being used, they may be placed outside the container. In this case, the element may be surrounded by a solid ring, comprising radial axes with foldings connecting the ring with the vibrators. The element is suspended from a flange at its outer end, under which a packing and for instance spiral springs support the element. A flange supporting the element is provided on the inner surface of the container. When cylindrical sieve or filter cylinders are being used, a circular vibrating motion is quite suitable, however, when planear or slightly curved filtering surfaces are being used, linear vibrating is applicable. In pulp washing a very short stroke is preferably used, for instance 0.5 mm, but in pulp screening the stroke may be for instance 5 mm. In pulp screening , the same device may first separate large impurities, and subsequently smaller ones. The design should allow for the forces generated by large suspension volumes being discharged from the device. The amount of suspension material to be treated is controlled such that the amount of all the fractions leaving the equipment is controlled with a valve or any other appropriate device. The treatment aims at taking the pulp or similar, if possible in a highly consistent state, in a single operation through the various devices, for instance by pumping, without intermediate containers. In pulp washing, the appropriate pulp layer thickness is generally about 5 cm. If the layer is much thicker than this, the flow-through rate of the liquid will slow down significantly. A similar method for suspension washing, screening, thickening etc. may be carried out without vibrators. In this case, the material to be treated is moved through the treatment conduits with say, a conventional high-consistency pulp pump or any other propulsion device. The device may then operate in any position and its shape may vary appreciably. When the method is applied to pulp thickening without vibrating, clogging of the treatment conduits is prevented by introducing a suitable amount of rinse water into the pulp. In the process, the high-consistency pulp to be washed is fed continuously with a high-consistency pulp pump through the set of treatment conduits in the treatment element, one wall of the conduits consisting of the wall of the wash liquid conduit, provided with several washing liquor inlets, through which washing liquor is conducted through the pulp layer under overpressure. On the other side of the pulp layer, the wall of the treatment conduit consists of the lye fraction collecting and surface of the filtering surface of discharge conduit. This filtering surface may appropriately be a metal sheet provided with small slots or holes parallel to the pulp flow direction. An unlimited number of these conduits for wash liquid, pulp to be washed and lye fraction can be located close to each other, according to the need. In this manner, the capacity of the device will be very high with regard to the space requirement, and also economic in terms of energy consumption. A preferred container shape for the suspension treatment without vibrating described above is a conical container tapered upwards, the suspension being introduced into its upper part by pumping, and distributed from there into several treatment conduits having an annular cross-section. The radial width of the treatment conduits preferably increases downwards to match the conical obliqueness, whereas the width of the treatment agent conduits and the lye fraction conduits remains unchanged from the top to the bottom of the conduit. This arrangement promotes the downward movement of the pulp and reduces the risk of clogging. Hot air or steam could also be advantageously used in such a treatment device for pulp thickening. In addition to continuous pulp feed into the container by means of a pump and to the filtering surfaces being kept clean under the pumping effect, the container may be equipped with vibrators in a manner known per se, the vibrators vibrating the device continuously or periodically in a linear direction parallel to the pulp feed direction, preferably being vertical. By estimation, accomplished as described above, the washer would have a diametre of only 4 m even at a large pulp plant. When a cylindrical, vertically operating container is being concerned, the action of vibrators may be replaced with a rotor, which is solidly attached to the central axis and is provided with blades, which circulate in the treatment conduits of the device as the rotor is rotating. In rotating, the blades sweep the screen or sieve surface of the treatment conduits, generating alternating suction and pressure pulses on these surfaces and the holes in these, which are thus cleared of impurities. The sieve surface having been appreciably increased without significant extra costs or space requirement, the hole size of the sieve surfaces may be further reduced. The reduced holes and slots in the sieve surface allow refuse to be more carefully separated. Solid substances may also be treated in accordance with thi . nvention. This treat¬ ment is carried out by dry means on the sieve or filter surfaces of the treatment conduits. The method is for instance appropriate for screening dry components, for filtering components from flue or other gases, for air purification, for grain or corn sorting and drying, for sand straining and for treating components with steam or gaseous substances. In such an embodiment, the component deposits are aerated with air or gas jets while the components are being vibrated at high frequency in the treatment conduits. Such a treatment of solid substances by dry means can be accomplished in devices whose shape and position may vary greatly, depending on the circumstances. In many cases the treatment conduits are fitted vertically nested into a cylindrical vertical container. The vibrator is preferably fitted on the central line of the con¬ tainer. When the device is used for instance for air filtering, electrically charged filtering surfaces may be used. The device is preferably curved in the forward direction of the process, because curved sieve or filter surfaces resist vibrating better than straight surfaces. A straightforward manufacture is an additional economic aspect of the device of the invention. Except for the embodiment including blade arms, the cylindrical devices need not be exactly circular, and vibrators can be acquired from special manu¬ facturers. The devices can be transported in parts to the installation site. The invention will be described in detail below with reference to some preferred embodiments and the accompanying drawings, of which: figure 1 shows a lateral view of a continuously operating sulphate pulp washer. The upper part of the container in the figure is a known upper part of a blowing container; figure 2 is a schematic top view of a pulp washer of another embodiment, the washing conduit system having been excluded for clarity's sake; figure 3 is a schematic perspective projection of a partial vertical section of the pulp washing element of figure 1; figure 4 is a schematic view of a partial vertical section of the two downwardly expanding pulp flow conduits of the pulp washing element of figure 1 including filtering surfaces; figure 5 is a schematic view of a vertical section of a paper pulp screen of another embodiment; figure 6 shows a vertical section of a continuously operating sulphate pulp washer of still another embodiment; figure 7 shows a continuously operating sulphate pulp washer of figure 6, provided with a vibrator in this case and figure 8 shows a front view of a vertical section of a dry component screen of a further embodiment. The pulp washing equipment illustrated in figure 1 comprises a cylindrical vertical container 24 having a diametre of approx. 3 to 4 mm. The upper part of the vertical container is provided with an inlet 28 for pulp to be washed, through which the pulp to be washed may flow into vertical, annular pulp flow conduits 2, 4, 6, 8, 10, 12, 14 and 16. The radial width of these conduits is under 10 cm, most appropriately approx. 5 cm. We note that the conduits are shown on a larger scale than the container itself. In reality the container could hold tens of conduits. However, a markedly smaller number of conduits is enough to meet the capacity required. The pulp flow conduits are located between the annular wash liquid conduits 1, 5, 9, 13 and 17 and the annular filtrate conduits 3, 7, 11 and 15. These wash liquid and filtrate liquid conduits have been divided with six intermediate bottoms into seven zones I- VII on top of each other. In addition, the upper and lower ends of these conduits have been sealed with plates. The wash liquid conduits in the lower zone have been connected to a water inlet pipe not shown. The vertical walls of the wash liquid conduits are provided with small holes for conducting wash water under overpressure through the pulp layers to be washed towards the filtering surfaces 52 of the filtrate conduits, figure 4. The filtrate removed from the uppermost filtrate conduit zone 1 is pumped into the upper part of the container, being admixed with the pulp in order to recover pulp fibres from the pulp. The lye filtrates separated from the other zones II to VII are pumped to serve as wash liquid in the upper zone I- VI, respectively, on the conventional counter-current principle. At the outer edge of the washing element 34 there is a horizontal flange 27 surrounding the entire element, by means of which the element and its packings bear against the pressing spiral springs 45 on the flange 25 supported on the inner surface of the container 24, figures 1 and 2. The filtrate and wash liquid pipes leading to the pumps and from there on may be located in the intermediate space 36 shown in figure 2. For pulp removal, the lower part of the container 24 is provided with a diluting water piping 18 including control valves, a conical bottom part 23, a pulp mixer including a shaft 19 and a motor 22, a valve 20 for controlling the pulp output flow and an outlet opening 21 for washed pulp. The control valve 20 serves for controlling the flow-through rate of the pulp to be washed throughout the treatment. An eccentric vibrator is placed inside the protective pipe 33 in the middle of the filtering element 24 and is connected by the shaft 32 to its motor 30. A pipe 31 with a valve is connected to the cover 29 of the container, so that accumulated air can be evacuated from the upper part of the container whenever necessary. The flow conduits are placed in the filtering element 34 in the following order: Wash liquid + pulp + filtrate + pulp + wash liquid + pulp + filtrate + pulp + wash liquid + pulp + filtrate + pulp + wash liquid + pulp + filtrate + pulp + wash liquid. As the pulp is being washed, wash liquid flows through the pulp layer and pushes lye into the filtrate space, filtrate reaching this space also from the second pulp layer under the propulsion of wash liquid, etc. Figure 2 shows two filtering element halves 34, to which solid plates 35 have been connected such that these halves may act separately from each other. The solid plates are connected to the protective pipe 33 of the vibrator so as to conduct the vibrating motion from the centre towards the outer periphery. The vertical conduits 36 between these solid plates may be used for fitting filtrate and wash liquid pipes. When necessary, several such solid plates may be placed in the container. Figure 3 shows a flange 25 fixed to the inner surface of the container 24. Spiral springs 45 and a packing have been placed on top of this. The flange 27 of the washing element is on top of the spiral springs. The wash liquid compartments of the various zones I to VII are numbered 1, 46, 47, 48, 49, 50 and 51 at the bottom, where water ' is used as wash liquid. Figure 4 illustrates two downwardly extending flow conduits 37 with filtering surfaces 52 for the pulp to be washed. The screen shown in figure 5 is devised for removing impurities from the pulp in connection with production and the paper-making machine. It is pressure-proof and the pulp is pumped through it. Current pressure screens comprise only one or two sieve cylinders. The screen decribed above may optionally comprise a great number of sieve cylinders, depending on the capacity desired. The screen in figure 5 has six sieve cylinders. It comprises a housing 102 shaped as a vertical cylinder and equipped with a cover 101, provided with a pulp inlet 103, an outlet 104 for accepted pulp fraction, an outlet pipe 105 for reject pulp and an inlet pipe 106 for diluting water. A vertical axis 107 is mounted onto bearings and sealed on the central line of the housing, and this axis can be rotated by a motor 108 with V-belt drive. For instance four horizontal, radial arms 110 are fixed to the upper end of this axis. Blades 111 which during operation circulate in six treatment conduits 112 have been very firmly attached in a vertical position to these arms so as to generate alternating suction and pressure pulses on the sieve surfaces 113. With the screen in operation, the pulp flows through six annular treatment conduits from the top towards the bottom. Having passed through the holes, the accepted pulp leaves the screen through the outlet 104, and the reject is discharged through the pipe 105. The blades may be previously known hydrofoil blades, or they may be provided with protuberances or ridges with a view to produce the pulses above. The pulp can be diluted in the various screening zones by introducing water from the pipe 106 through the holes provided in the diluting water conduits 114 into the pulp. Only a few of the blades are shown in the figure. Blades are provided in each treatment conduit in the vicinity of the sieve surface to prevent clogging of the surfaces. The cellulosic pulp washer shown in figure 6 includes a conical vertical container 226, having an inlet opening 227 for pulp to be washed at its upper part. On top of the container a high-consistency pump 228 (pulp consistency from about 8 to 12%) is provided, which moves the high-consistency pulp to be washed through the three annular treatment conduits 230 into the washing element 225. In order to ensure that the pulp flows evenly towards its outlet openings 206, 207, 208, 209, 210 and 232, these treatment conduits expand towards their outlet openings 232. On one side of each treatment conduit there is a washing liquid conduit 229 and on the other side a collecting and outlet conduit 231 for separated lye fraction. The sieve surface of the outlet conduit is marked with reference numeral 213 and the holes in the wall of the washing liquid conduit with reference number 233. As shown in the figure, the pulp may be washed in the washer on the counter-current principle in five zones I to V, for which separate wash liquid and lye fraction conduit rings are provided. In zone V hot water is used for pulp washing. The fraction lye from said zone is pumped to serve as wash liquid in zone IV and the fraction lye from the latter zone is pumped into the zone III, and so on. Since the fraction lye from zone I may contain fibres, it can be pumped back into the top of the container. A suitable pulp layer thickness, i.e. treatment conduit width, is e.g. in the range from 5 to 15 cm. Even at a large pulp plant, the entire production can be washed in a single washer having a diametre below 6 m, since the filtering surfaces cover a very small space. This method saves much plant space and costs compared to conventional methods. Figure 7 shows a cellulosic pulp washer which is identical to the one in figure 6 except for the two vibrators 211. The vibrators, which are fixed to the sides of the container 226, vibrate the washer continuously or periodically in a linear vertical direction. The vibrators further enhance the operation of the washer. Even a large pulp plant would probably get along with a single washer having a diametre under 4 m. Instead of a vibrator, for instance a hydraulically operating device can be used, which allows the container, or optionally the filtrate conduits alone, to sink slowly, and which occasionally lifts the container, or optionally the filtrate conduits, rapidly upwards. Such an agitating movement of the device will actively loosen the pulp to be treated from the sieve surface. Figure 8 shows a dry component filter/screen 301, which serves for instance to purify flue gases. The device is shown as a lateral section. It has a rectangular cross- section. The device, marked with reference numeral 301, has an inlet opening 302 for components to be treated, coarse fraction outlet openings 315 and fine fraction outlet openings 316. The screen has the curved shape of a quarter of a circle, and a vibrator 305 is placed on its concave surface. The vibrator may vibrate the screen linearly with 1000 to 3000 strokes a minute, over a stroke length of 0.5 to 5 mm. In the case of filtering, a 0.5 mm stroke length is roughly appropriate, and in screening, the stroke lenght should be about 5 mm. The screen contains three component treatment conduits 303 and two treatment agent conduits 306, divided into three zones I, II and III. At the first end of the two treatment agent conduits zone I has blast air inlet openings 312, the central zone II has air inlet openings 313 and the final zone III air inlet openings 314. The sieve surfaces 304 are provided with holes of an appropriate size, through which the fine fraction reaches the fine fraction collecting and discharge conduits 317 under the effect of blast air. The numeral 307 marks inlet openings for treatment agent, i.e. air. The screen is supported by support studs 311. Owing to its curved shape, the screen stands vibrating well. The method and the device of the invention has a very large field of application, as indicated above. The device of the invention may vary greatly in various embodiments. In a version not described here the treatment agent conduit has been replaced with a solid wall crossed by transverse pipes with feed inlets for treatment agent feed into the treatment conduits. Other embodiments included in the scope of protection of the claims occur abundantly, however, they are obvious to persons skilled in the art.

Claims: Claims 1. A method for treating solid, liquid or gaseous substances or intermediate forms of these, particularly pulp suspensions, on a sieve or filter surface (52) by means of a treatment agent, whereby the substance to be treated is continuously circulated in an open or closed circuit through a plurality of juxtaposed treatment conduits (2, 4, 6, 8, 10, 12, 14;37) operating in parallel, and the treatment agent is conducted from the treatment agent conduits (1, 5, 9, 13, 17) to the treatment conduits (3, 7, 11, 15), from where the substance having passed through the sieve or filter surface is discharged into the filtrate conduits, the holes in the sieve or filter surfaces being cleared of clogging components with an external force, such as vibrating and/or a pressure force exerted on the flow through the holes, and/or by gravity of the component clogging the holes, characterised in that one wall of the treatment conduits (2, 4, 6, 8, 10, 12, 14; 37) consists of a treatment agent conduit (1, 5, 9, 13, 17), treatment agent being fed through its plurality of feed inlets, and the opposite wall of the treatment conduits consisting of the sieve or filter surface (52) of the filtrate conduit (3, 7, 11, 15), this arrangement being repeated such that on one side of each treatment conduit there is a treatment agent conduit, and on the opposite side of the treatment conduit there is a filtrate conduit, a treatment conduit thus being always provided on either side of a treatment agent conduit, and respectively a treatment conduit on either side of a filtrate conduit, so that treatment agent passes into adjacent treatment conduits, from where the substance having passed through the sieve or filter surface passes into the adjacent filtrate conduit. 2. A method as claimed in claim 1, characterised in that the treatment conduits (2, 4, 6, 8, 10, 12, 14; 37) and the filtrate conduits (3, 7, 11, 15) are divided into separate zones I- VII in the forward direction of the process, and that the various treatment conduit zones are supplied with filtrate recovered from the various filtrate conduit zones on the counter-current principle and/or with fresh treatment agent. 3. A method as claimed in claim 1 for instance for purifying flue gases, characterised in that the holes in the sieve or filter surfaces (304) are cleared of clogging components by a momentary change of direction of the flow through the holes. 4. A method as claimed in claim 1 for instance for purifying flue gases, characterised in that the holes in the sieve or filter surfaces (304) are cleared of clogging components for instance by pulsating air blowing. 5. A method as claimed in claim 1 or 2, characterised in that the holes in the sieve or filter surfaces (304) are cleared of clogging components by high-frequency vibrating, preferably at a frequency of 1,000 to 3,000 strokes a minute and with a stroke length in the range of 0.5 to 5 mm. 6. A method as claimed in claim 1 or 2, characterised in that treatment agent is continuously or periodically introduced into the treatment conduits. 7. A method as claimed in any of claims 1 to 6, characterised in that treatment agent is fed into the treatment conduits under even or varying pressure. 8. A method as claimed in any of claims 1 to 7, characterised in that the substance to be treated, for instance cellulosic pulp to be washed, bleached, thickened or screened, is introduced into vertical treatment conduits (2, 4, 6, 8, 10, 12, 14; 37), where it sinks by gravity. 9. A method as claimed in any of claims 1 to 7, characterised in that the substance to be treated, for instance cellulosic pulp to be washed, bleached, thickened or screened, is pumped through the treatment conduits (230). 10. A method as claimed in any of claims 1 to 9, characterised in that the direction of the treatment conduits (303), the treatment agent conduits (306) and the filtrate conduits (317) is alternately vertical and horizontal. 11. A method as claimed in claim 1, in which the substance to be treated, for instance cellulosic pulp, is introduced into vertical conduits with an annular cross- section, characterised in that the holes in the sieve or filter surfaces (113) are continuously cleared by blade members rotating in the treatment conduits (112), generating alternating suction and pressure pulses on the sieve and filter surfaces. 12. A device for perforating the method defined in claim 1, in which solid, liquid or gaseous substances or intermediate forms of these, particularly pulp suspensions, are treated on sieve or filter surfaces (52) by means of a treatment agent, the substance to be treated being continuously circulated in an open or closed circuit through a plurality of juxtaposed treatment conduits (2, 4, 6, 8, 10, 12, 14; 37) operating in parallel, the treatment agent being conducted from the treatment agent conduits (1, 5, 9, 13, 17) to the treatment conduits, from where the material having passed through the sieve or filter surface is discharged into the filtrate conduits (3, 7, 11, 15), the holes in the sieve or filter surfaces being cleared of clogging components by an external force, such as vibrating and/or a pressure force exerted through the holes, the device comprising a container (24), provided with a feed inlet (28) for substance to be treated, a plurality of juxtaposed treatment conduits (2, 4, 6, 8, 10, 12, 14;37) operating in parallel, a sieve or filter area (3, 7,11, 15), means for feeding treatment agent into the device, for removing filtrate from the device, and for clearing the sieve or filter surface holes from clogging components, such as a vibrator, and/or a pneumatic device acting on the flow through the holes, the container further comprising means for removing the treated substances and the filtrate, characterised in that one wall of the treatment conduits (2, 4, 6, 8, 10, 12, 14;37) consists of a treatment agent conduit (1, 5, 9, 13, 17), comprising a plurality of feed inlets for introducing the treatment agent into the treatment conduit, in that the opposite wall of the treatment conduits consists of a sieve or filter surface (3, 7, 11, 15), the set-up being arranged to be repeated such that on one side of each treatment conduit there is a treatment agent conduit, and on the opposite side of the treatment conduit there is a filtrate conduit, a treatment conduit being thus always provided on either side of the treatment agent conduit, and respectively a treatment conduit on either side of the filtrate conduit, so that treatment agent passes into adjacent treatment conduits, from where the substance having passed through the sieve or filter surface respectively passes into the adjacent filtrate conduit, and thus the conduits form a compact set in terms of space requirement. 13. A device as claimed in claim 12, characterised in that the set of conduits consists of eccentric conduits having the shape of the mantle surface of a cylinder (24; 102) or a cone (226). 14. A device as claimed in claim 13, characterised in that the treatment conduits (37; 230) converge from the top downwards, whereas the width of the treatment agent conduits and filtrate conduits remains the same from the top to the bottom. 15. A device as claimed in any of claims 12 to 14, characterised in that the container is open or pressure-proof and that it has a cylindrical (24; 102), conical (226) or box-like (301) shape, and contains a set of conduits with a matching shape forming a treatment element, and in that the substance to be treated is disposed to move from the top downwards in the treatment element. 16. A device as claimed in claim 12, characterised in that the container (301) has a rectangular cross-section and is curved in the treatment direction, and in that the set of conduits comprises plate-like conduits (303, 306, 317) matching the curvature of the container. 17. A device as claimed in any of claims 12 to 16, characterised in that the treatment agent conduits and the filtrate conduits are longitudinally divided into different zones I to VII, and in that the filtrate conduits of each zone are equipped with outlet pipes (206 to 210), and the treatment agent conduits of each zone are respectively equipped with inlet pipes. 18. A device as claimed in claim 12 or 13, characterised in being equipped with a rotating set of blades (107, 110, 111), the blades (111) being fitted to rotate in the treatment conduits (112) on the sieve or filter surface (113). 19. A device as claimed in claim 12 for treating solid substances by dry means, characterised in that the filter surfaces (304) are electrically charged. 20. A device as claimed in any of claims 12 to 18, characterised in that the treatment agent is replaced with a wall, in which a for instance spiralling pipe for treatment agent has been fitted, and in that the pipe comprises openings to either side of the wall for feeding treatment agent into the treatment conduits. 21. A device as claimed in any of claims 12 to 20, characterised in that the substance to be treated consists of cellulosic pulp to be washed, thickened or screened, or any suspension, flue gas or other gas, sand or similar grain to be purified, and in that the treatment agent consists of a filtrate, and/or water and/or air or any other gas recovered on the counter-current principle.

Inventors: AREMAA TOIVO, AREMAA, TOIVO
Applicants: AREMAA TOIVO, AREMAA, TOIVO
Application year: 1995
Main classification: D21C9
IPC codes: D21C9, F26B17