Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/04—Filters with filtering elements which move during the filtering operation with filtering bands or the like supported on cylinders which are impervious for filtering
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/35—Filters with filtering elements which move during the filtering operation with multiple filtering elements characterised by their mutual disposition
  • B01D33/41—Filters with filtering elements which move during the filtering operation with multiple filtering elements characterised by their mutual disposition in series connection
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/44—Regenerating the filter material in the filter
  • B01D33/48—Regenerating the filter material in the filter by flushing, e.g. counter-current air-bumps
  • B01D33/50—Regenerating the filter material in the filter by flushing, e.g. counter-current air-bumps with backwash arms, shoes or nozzles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/58—Handling the filter cake in the filter for purposes other than for regenerating the filter cake remaining on the filtering element
  • B01D33/62—Handling the filter cake in the filter for purposes other than for regenerating the filter cake remaining on the filtering element for drying
  • B01D33/66—Handling the filter cake in the filter for purposes other than for regenerating the filter cake remaining on the filtering element for drying by gases or by heating
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2201/00—Details relating to filtering apparatus
  • B01D2201/08—Regeneration of the filter
  • B01D2201/085—Regeneration of the filter using another chemical than the liquid to be filtered

Definitions

• the invention relates to a method for separating substances from mixtures, in which the mixture is passed through a filter medium, at the inlet side of which the substances are retained, whereupon they are detached and removed from the filter surface by a cleaning agent, and a device for carrying out the Procedure.
• the separation of substances from mixtures is an extensive field of process engineering. In line with the diversity of the mixtures to be treated, the number of processes for separating substances from these mixtures is correspondingly large.
• the present invention relates to a method in which a filter medium in the form of a thin-walled flat structure, for example a sieve, is used, on the surface of which the substances to be separated are retained. In order that the operation with such a flat structure can be maintained, the separated particles have to be removed again, since otherwise the openings of the filter medium, which cause the separation of the substances, are gradually closed and the filter effect is thereby reduced.
• sieve filtration the type of filtration referred to as deep-bed filtration is also known.
• the invention relates to a method and a device in the field of sieve filtration.
• the filter medium is stationary, which is why a cleaning device is provided which is moved along the stationary filter medium and carries out the cleaning of the filter medium.
• a cleaning device is provided which is moved along the stationary filter medium and carries out the cleaning of the filter medium.
• the filter medium is cleaned from both sides by treating the discharge side with a pressurized water jet, with which the separated substances are loosened and lifted off the surface of the filter medium, while the substances detached from the filter medium are sucked off on the inlet side.
• This embodiment of sieve filtration works reliably as long as the pressurized water jet is sufficient to detach the separated substances from the surface of the filter medium. Sticky and slimy substances, on the other hand, are difficult to remove.
• the pressure water requirement is high in relation to the slurry to be cleaned.
• the filter medium moves through the mixture to be cleaned, the deposited substances being separated and drained off from the surface of the filter medium at a cleaning point located outside the mixture.
• Various constructions are known for this purpose, for example belt rotating filters.
• the solids are separated off on the surface of the filter medium mechanical means or by pressurized water.
• the mechanical cleaning agent places additional strain and wear on the filter medium, while the use of fi ltrate is correspondingly high for pressurized water applications.
• the ratio of liquid to solid is very high.
• a heated cleaning medium is used as the cleaning agent for the filter surface and the filter surface on the outlet side is irradiated with the cleaning medium and the substances are thereby removed from the filter surface.
• the cleaning medium with which the filter surface is treated appropriately water vapor with or without additives such.
• chemical or surface-active type can be added, wherein at least partial saturated steam or superheated steam can be added to the cleaning medium.
• the invention also relates to a device for separating substances from mixtures with the aid of at least one filter surface, on the inlet side of which the substances settle, a cleaning device for removing the separated substances being provided on the filter surface.
• the task of this device is to enable an optimal separation of substances; This is achieved in that the filter surface is designed as a continuous, endless filter belt, to which a cleaning point with a cleaning device is assigned outside of the filter surface acted upon by the mixture, in which at least one Nozzle for blasting the filter surface in the passage with a blasting medium and a collecting means for receiving and removing the substances removed from the filter surface are provided, the blasting medium being heated with water and / or water vapor with or without chemical additives, e.g. B. contains surfactant additives.
• the filter belt is expediently guided above deflection rollers above the filter surface acted upon by the mixture, through which the filter belt forms a cantilevered part, on which a system for collecting and transporting the substances detached from the filter belt is arranged.
• Fig. 3 shows a schematically represented side view of the drive for the device according to FIG. 2, and
• Fig. 4 shows a side view of a detail of the drive according to FIG. 3.
• the device shown in Figure 1 is used to separate solid substances from liquids, for example from chemical and other industrial or municipal waste water.
• the lower half of the device dips into the liquid 1, the level 2 of which on the inlet side is somewhat higher than the level 3 on the outlet side of the device.
• a filter surface 5 which is designed as an endless filter belt and has openings of a certain size in accordance with the desired filtering effect.
• the filter surface 5 is shown as a screen surface 6 in sections.
• the filter surface 5 is guided on two rollers 9, 10, of which the roller 9 is the drive roller and the roller 10 is the deflection roller. Only the deflection roller 10 is immersed in the liquid 1.
• the drive roller 9 which is designed as a continuous' Band Filterfikiee 5 is over two Umlenkrol len 1 1, 12 out through which the Fi lterband 5 is a projecting part 15 with two legs 16, forms 17th
• the number of nozzle tubes 18 can vary; one nozzle tube or two or more nozzle tubes 1 8 can be used.
• a funnel-shaped collecting device 19 is arranged, through which the solids are collected and in a transport device 20, for. B. a container.
• the filter belt 5 is irradiated through the nozzle tubes 18. It is essential that the cleaning medium used for this contains heated water with or without the addition of gas, fluid and solids.
• the cleaning medium can contain at least partially pure saturated steam or superheated steam, and alone or with additives, e.g. B. ien surface-active material and other chemicals to support the cleaning effect on the outlet side of the filter belt 5 are irradiated.
• the cleaning medium can be adapted by appropriate composition.
• the type of filter belt can also be designed according to the filtering task to be solved.
• the separated solids on the Detaching side of the filter belt 5 loosened and removed so that they fall into the funnel-shaped collecting device and then into the transport device 20.
• the treatment of the filter belt 5 with hot water with or without the addition of steam as a cleaning medium offers considerable advantages.
• the solids detached from the filter belt 5 have a comparatively very low moisture content, so that the solids are practically obtained as dry matter and can even be fed directly for further use, for example combustion or composting.
• the cleaning device 14, which is composed of the nozzle tubes 18, the collecting device 19 and the transport device 20, can also be used to clean filter belts 5 which cannot be cleaned using the known methods and devices, for example sticky and slimy solids.
• the treatment carried out with the nozzle tubes 18 leads, even with such materials, to a quick cleaning of the filter belt and to the accumulation of a relatively dry solid product.
• the cleaning device 14 can also be arranged on a run of the filter belt 5.
• the nozzle tubes 18 are arranged on the outlet side of the filter belt and the collecting device on the inlet side of the filter belt.
• walls 22 are also indicated, which limit the inflow of liquid 1.
• the two strands of the filter belt 5 are covered in the immersed area (not shown), so that the liquid flows from both sides between the two strands and the filtrate runs perpendicularly thereto in the direction of the arrows 23.
• the two dreams do not need to be exactly vertical, but can also be arranged obliquely.
• the drive roller 9 and Cleaning device 14 arranged above the level 2, 3 of the liquid.
• the inner filter belt 25 has a drive roller 29 and a deflecting roller 30. Both fi lter bands 5, 25 have projecting portions 15, 35, of which that of the filter band 25 protrudes into the projecting part 15 of the fi lter band 5.
• the deflecting rollers forming the projecting part are denoted by 1 1, 12 and 31, 32.
• Nozzle tubes 18, 38 are used for both cantilevered parts 15, 35. As shown in the lower nozzle tubes 18, these are moved back and forth by means of a crank mechanism 36 through the rotating deflecting roller 11. The same device is of course also possible for the nozzle tubes 38 by coupling to the deflection roller 31.
• the inner filter belt 25 expediently has a smaller mesh width than that of the outer filter belt 5. Depending on the amount of material, only one filter belt can be in operation or the belts can run at different speeds. Otherwise, the cleaning device 14 can be designed in the same way as in the embodiment according to FIG. 1. This means that only one collecting device 19 with one transport device 20 is provided. Because of the smaller mesh size of the inner filter belt 25, the solid particles obtained there are smaller than the mesh size of the outer one Filter belt 5 so that they can pass through the filter belt 5.
• FIG. 3 shows a section of the device according to FIG. 2, individual parts being omitted for the sake of a better overview.
• the inner filter belt 25 with the smaller mesh size than that of the filter belt 5 is somewhat narrower than the filter belt 5 and runs over two drive rollers 29, which are smaller than the drive rollers 9 of the filter belt 5.
• the deflection rollers 26, 30 of the two filter belts 5, 25 are only indicated schematically. These also consist essentially of two rollers on which the two filter belts 5, 25 are guided.
• the filter belts 5, 25 rest on drive belts 39, as will be explained in detail with reference to FIG. 4.
• the part of the device lying above the mixture is expediently protected by a cover 45.
• the inner drive rollers 29 are arranged freely running on the motor shaft 42 and connected to the second drive roller 29 with a hollow tube (not shown). Between the outer drive roller 9 and the drive roller 29, a clutch 43 is arranged, for example an electromagnetically switchable clutch, the switching energy of which is supplied by a feed line in the motor shaft 42.
• FIG. 4 also shows how the two filter belts 5, 25 are guided on the drive rollers 9, 29.
• the filter belt 5 is driven by the drive roller 9 and the deflection roller 10 Drive belt 21 placed, which has a toothing 43 on the inside, which meshes with a toothing 44 of the drive roller 9.
• the same arrangement of a drive belt 21 with a toothing 43 is arranged on the opposite edge of the filter belt 5.
• the filter belt 5 rests with its edges on the two drive belts 21, which expediently consist of plastic and therefore protect the filter belt 5.
• the speed of the drive motor 40 can be steplessly regulated, while the connection and the speed of a filter belt can also be regulated according to the operating conditions that occur.
• the devices described have an extremely effective cleaning device, the operating costs are also favorable, in particular if biogas can still be used to heat the cleaning medium.
• An essential area of application of the device described will undoubtedly be the treatment of industrial and municipal wastewater.
• This additive can be, for example, a surfactant additive referred to as a surfactant, which is added to the cleaning medium, as a result of which the process of dissolving and decoding the filter surface can be considerably accelerated. Since the viscosity of the dirt material on the filter surface can be reduced, the entire cleaning process is accelerated and simplified.
• a surfactant to be added to the cleaning medium must have good water solubility and be biodegradable, and it must also have good temperature and hydrolysis stability.
• filter tapes with a very small mesh size are used, it is possible to use the devices described, for example in the event of oil accidents, since the addition of the oil mentioned is achieved with very small amounts of water and the equipment required for this can be kept considerably smaller than in the known devices.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Filtration Of Liquid (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=4281564

Family Applications (1)

Country Status (2)

Cited By (5)

Families Citing this family (1)

Citations (3)

• 1988
  • 1988-12-21 CH CH4733/88A patent/CH678282A5/de not_active IP Right Cessation
• 1989
  • 1989-12-18 WO PCT/CH1989/000219 patent/WO1990006800A1/de unknown

Patent Citations (3)

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