Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
  • B01D61/36—Pervaporation; Membrane distillation; Liquid permeation
  • B01D61/364—Membrane distillation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D63/00—Apparatus in general for separation processes using semi-permeable membranes
  • B01D63/10—Spiral-wound membrane modules
  • B01D63/101—Spiral winding
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
  • Y02A20/00—Water conservation; Efficient water supply; Efficient water use
  • Y02A20/124—Water desalination
  • Y02A20/131—Reverse-osmosis

Definitions

• the invention relates to a salt water distillation device according to the preamble of claim 1, which is used in particular for the production of fresh water from sea water.
• membrane distillation which is derived from the magazine Chem.-Ing.-Tech. 56 (1984) No. 7, pages 514 to 521. From this document and US Pat. No. 3,340,186 it is already known to wind up the individual layers contained in the device in a spiral, so as to achieve a compact structural arrangement with a large distillation area.
• the efficiency of the known salt water distillation devices is limited by the fact that the turbulence within the hot concentrate stream and within the cooling liquid stream is too low.
• an increase in the turbulence must not result in an excessive pressure loss between the flow inlet and outlet, because this would again increase the energy consumption of the device too much.
• the aim of the invention is therefore to create a salt water distillation device of the type mentioned at the outset, the efficiency of which is increased by increased turbulence in the hot water and cooling channels, but the pressure loss occurring in the individual channels remains low.
• the invention is significantly developed by the features of claims 6 to 9. Because a special distillate spacer grid is provided in the distillation chamber or channel, the distillate can be discharged largely without resistance and unhindered and without the formation of pockets in the direction of the path of the hot concentrate.
• the embodiment according to claim 10 is useful to the unreinforced layer of the membrane against the distillate to protect the support grid, which can be designed according to the requirements of proper spacing and removal of the distillate in the distillate channel.
• FIG. 1 shows a schematic cross section through part of the spiral winding of a salt water distillation device according to the invention
• FIG. 2 shows a top view of a hot concentrate or cooling liquid spacer grid for a salt water distillation device according to the invention
• FIG. 3 shows a section along line III-III in FIG. 2,
• Fig. 4 is a schematic plan view of a distillate spacer grid according to the invention.
• Fig. 5 is a cal atic section along line VV in Fig.4.
• Fig. 1 shows only a section of a spiral wrap for a salt water distillation device according to the invention.
• the various positions shown in FIG. 1 repeat themselves radially outwards and inwards to an outermost or innermost position, which radially supplies the unheated cool sea water K or radially inwards the heated sea water W in countercurrent or the distillate D formed is removed radially outside.
• the core component of the spiral wrap is two microporous membranes 12 arranged on the two surfaces of a hot concentrate spacer grid 11, which have the property that they let steam through, but not water or salt molecules.
• a water-permeable protective layer 18 which can be designed, for example, as a perforated plastic film and represents a support layer for the actual membrane 12.
• a protective layer grid 19 indicated by dots, which can have the shape of a fine fabric or a very thin perforated film.
• a distillate spacer grid 17 adjoins the water-permeable protective layer 19 radially outwards or inwards, followed by a water and vapor-impermeable condensation film 13 on the outside or inside, on which a coolant is applied radially from the outside or radially from the inside.
• Spacer grid 14 connects, which is again covered on the outside or inside by a water and vapor impermeable condensation film 13.
• the spiral wrap is tightly sealed by cast synthetic resin plates, so that the outer or inner circumferential side introduced liquid is forced to flow on spiral tracks from the outside in or from the inside out.
• unheated and preferably cool sea water K flows into the space containing the cooling liquid spacer grids 14 between two condensation foils 13, which sea water K is discharged axially in the center of the spiral winding (not shown) and is fed to a heating device which is preferably heated by solar energy .
• the heated sea water is fed back centrally into the winding and, in countercurrent to the cool sea water K as hot sea water stream W, is introduced into the space formed by the hot concentrate spacer grid 11, where it rotates counterclockwise in the spiral wrap radially from the inside flows outside.
• the heated sea water W which had largely been cooled up to that point, is again removed from the spiral wrap and either returned to the sea or passed through the spiral wrap in a further cycle.
• the distillate D collects in the space formed by the distillate spacing grid 17 and then flows counterclockwise in the direction of the arrows D in FIG. 1 in a spiral wrap gradually from the inside out, where it is then drawn off at the radially outermost positions can.
• the direction of flow of the unheated sea water K or of the heated sea water W is designated by R in FIG. 2.
• the webs 15, 16 of the two spacer grids 11 and 14 are clearly arranged at an angle of 45 ° to the flow direction R, while according to FIG. 3 the webs 16 are arranged on the webs 15 running at 90 ° to them , ie that the webs 16 and the webs 15 run in two different planes.
• the warp and weft threads extend in or perpendicular to the flow direction S of the distillate D, openings for the distillate D are thus provided in the circumferential direction over the entire axial extent of the spiral wrap, so that there is a uniform outflow of the distillate D over the entire axial length of the spiral wrap . This also significantly increases the distillation efficiency.
• the condensation films 13 are preferably designed as FEP films (Hostaflon-ET) and have a thickness of 150 ⁇ .
• the spacer grids 11, 14 are advantageously made of polypropylene or high density polyethylene.
• the distillation spacer grid 17 can also be made of the same material, but is only about 1/10 as thin as the spacer grid 11, 14.
• the condensation foils 13 can advantageously consist of cold-rolled stainless steel strip with a thickness of 0.2 mm.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Water Supply & Treatment (AREA)
• Separation Using Semi-Permeable Membranes (AREA)
• Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6359264

Family Applications (1)

Country Status (3)

Cited By (1)

Families Citing this family (9)

Citations (6)

Family Cites Families (5)

• 1988
  • 1988-07-21 DE DE3824839A patent/DE3824839C1/de not_active Expired
• 1989
  • 1989-07-21 EP EP89113470A patent/EP0351879A1/de not_active Withdrawn
  • 1989-07-21 WO PCT/EP1989/000860 patent/WO1990000928A1/de not_active Ceased

Patent Citations (6)

Non-Patent Citations (3)

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