JPH04290597A - Water treating equipment - Google Patents

Abstract

PURPOSE:To provide the recycled water treating equipment capable of completely separating the impurities from the concd. water generated from a water treating device and capable of being operated even in an agravity state. CONSTITUTION:The concd. water 106 from a water treating device 101 (mainly for membrane distillation) is atomized by a nozzle 108 in a crystallization part 117, brought into contact with the gas 107 heated by a heater 104 and vaporized, hence the impurities in concd. water are suspended in the gas as solid particles, and the particles are removed by a filter 111. The high-humidity gas 112 freed of the particles is separated by a dehumidifier 103 into water 114 and a gas 113, and the water 114 is returned to the water treating device 101 and the gas 113 to the heater 104. The moisture in the high-humidity gas 112 is absorbed in a liq. absorbent through a hydrophobic porous membrane in the dehumidifier 103, the moisture in the absorbent is recovered as water through another hydrophobic porous membrane, or the moisture in the gas 112 is cooled and condensed and then the water droplets and the gas are separated by the hydrophobic porous membrane.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regeneration and circulation system for domestic wastewater, and more particularly to water treatment equipment that can be used not only on land but also in closed space systems such as spacecraft and space stations, and even under zero gravity conditions.

0002

[Prior Art] Conventionally, water treatment equipment that purifies and reuses wastewater above ground has been used in "Water and Wastewater Handbook," Maruzen, 139-1.
As shown on page 42, physical and chemical treatments (neutralization, precipitation,
Drainage water is separated into fresh water and sludge through biological treatment (activated sludge method, biological oxidation pond method, etc.) and dissolved matter treatment (neutralization, sedimentation, coagulation, foam separation, etc.). ion exchange, adsorption, membrane separation, evaporation, oxidation, etc.) and sludge treatment (dehydration, drying, combustion). There are various methods for these treatments, including centrifugation, filtration, and natural dehydration for dehydration, heating drying for drying, and separation based on density difference using gravity for sedimentation and floating separation. is being carried out. Here, the conventional equipment structure for sedimentation separation, dewatering operation, and drying operation is described in "Water and Wastewater Handbook", Maruzen, 177.
〜180 pages, 455-461 pages, 492-496 pages and ``
"Chemical Engineering Handbook" Maruzen, pp. 441-450.

[0003] Furthermore, as a water treatment system in outer space, as described in Japanese Patent Application Laid-open No. 1982-19299,
Water treatment systems based mainly on separation methods using membranes have been proposed. In particular, for the production of drinking water in space,
Since phase change is essential, the above publication proposes a system using a membrane distillation method (thermopervaporation method) using a hydrophobic porous membrane.

0004

[Problems to be Solved by the Invention] In the above-mentioned conventional above-ground water treatment equipment, in addition to sedimentation, sedimentation, and floating operations using gravity, separated impurities (solids)
It is not suitable for use in zero-gravity space such as outer space, as the method of taking it out is done by scraping it off.

[0005] Furthermore, in the membrane separation-centered system as shown in the above-mentioned publication, which is intended for use in outer space, no specific method has been proposed for treating the concentrated water produced as a result of membrane distillation. There were problems in separating impurities from the concentrated water to construct a complete water recycling system.

An object of the present invention is to provide water treatment equipment that can be operated not only on the ground but also in zero gravity conditions such as in outer space, and that can completely separate concentrated water into impurities and water. Another object is to provide a water treatment facility capable of recycling the above-mentioned separated water.

[0007]

[Means for solving the problem] Impurities contained in the concentrated water are removed as particulate solids by atomizing concentrated water from a water treatment device in a crystallizer and vaporizing it by directly contacting it with hot gas. Impurities and water in concentrated water are completely separated by suspending them in gas and removing them with a filter. In addition, the gas containing moisture that has evaporated as a result of the above can be brought into contact with an absorbing liquid through a hydrophobic porous membrane or directly in a dehumidifying device, so that the absorbing liquid absorbs the moisture, or the moisture can be removed. The gas and water are recovered by cooling and condensing to form water droplets, and then separating the gas and water droplets using a hydrophobic porous membrane. The recovered gas and water are recycled to the water treatment device and crystallizer, respectively.

[0008]

[Operation] In the crystallizer of the present invention, in order to completely separate water from impurities contained in the concentrated water, the concentrated water is atomized and at the same time vaporized by hot gas. As a result, impurities in the concentrated water are precipitated and become particulates, creating a mixed flow of gas and particulates. This gas and particulates can be easily separated by using a filter or the like, thus making it possible to completely separate impurities in the concentrated water.

Furthermore, the moisture contained in the gas as a result of the vaporization is recovered by one of the following two means. One method is to bring this moisture-containing gas into direct contact with an aqueous solution (absorbing liquid) that easily absorbs moisture, or through a hydrophobic porous membrane that allows gas to pass through but not liquid. By this, the water in the gas is transferred to the absorbing liquid, and the absorbing liquid, which has become diluted as a result, is hydrophobic with water, which has a low temperature and a water vapor pressure lower than that of the absorbing liquid. 100% water is recovered by allowing water to absorb water from the absorption liquid by contacting it through a porous membrane. Another method is to cool the outside of a thin tube and flow the water-containing gas inside the tube, which causes the water to condense inside the tube and form a mixed flow of water droplets and gas, forming a hydrophobic porous membrane. By guiding the mixed flow inside the tube and extracting only the gas to the outside of the tube, the moisture and gas in the gas can be completely separated. The gas is returned to the crystallizer and the water is returned to the water treatment equipment.

By carrying out the above operations, a complete water circulation system can be created not only on the ground but also in outer space where there is no gravity.

[0011]

Embodiment FIG. 1 shows an embodiment of water treatment equipment according to the present invention. This device is composed of a water treatment device 101, a crystallizer 102, and a dehumidification device 103. The crystallizer 102 includes a gas heater 104, a crystallizer 115, and a filter 111. The crystallization section 115 is in the form of a cell in which a nozzle 108 is provided. Wastewater 105 from the closed space system is first sent to a conventional water treatment device 101. Concentrated water 106 generated by treatment in the water treatment device 101 is atomized by a nozzle 108 in a crystallization section 115 together with a gas (for example, air) 107 heated by a gas heater 104, and becomes water droplets 109. The impurities are vaporized and become fine particles 110. Highly humid gas containing vaporized water vapor and fine particles 1
The mixed flow of 10 is filtered by filter 111, and only particulates 110 are captured by filter 111. Gas (containing water vapor) 112 that has passed through the filter 111
is sent to the dehumidifier 103. The water 114 separated by the dehumidifying device 103 is returned to the water treatment device 101 or used as treated water 116 as is. Further, the dry gas 113 separated by the dehumidifier 103 is sent to the gas heater 104 to be reused. According to this embodiment, by attaching the crystallizer 102 and the dehumidifier 103 to the conventional water treatment device 101, impurities and water can be completely separated and removed from the concentrated water obtained by the water treatment device 101. In addition to this, it is also possible to recycle the separated and removed water.

In this embodiment, the crystallizer 102 and the dehumidifier 103 are used only for processing concentrated water, but they can also be used as a distilled water generating section, similar to membrane distillation.

FIG. 2 shows the embodiment shown in FIG. 1 in more detail with respect to the water treatment device 101 and in simplified form with respect to the crystallization device 102. The water treatment device 101 includes a filter 201, a reverse osmosis membrane device 202, and an activated carbon device 203.
, a sterilizing lamp 204 , and a membrane distiller 205 . In addition to this water treatment section 101, a crystallizer 102 and a dehumidifier 103 are provided. The crystallizer 102 is the same as the crystallizer 102 in FIG. Drainage water 208 from the closed space is continuously treated by a filter 201, a reverse osmosis membrane device 202, an activated carbon device 203, and a germicidal lamp device 204, thereby becoming domestic water 209 that can be used for showers and the like. Further, a portion 210 of this produced water 209 is treated in a membrane distiller 205. This membrane distiller 205 has a hydrophobic porous membrane 206
The water 210 described above flows cyclically on one side (raw water side), and the cooling water flows on the other side, and only water vapor permeates through the membrane 206 from the raw water side to the other side. There, the water vapor is cooled with cooling water and condensed to produce high-purity water2.
11 (which can be used as drinking water), and on the other hand, concentrated water with a high concentration of impurities is produced on the raw water side.

In the water treatment apparatus 101 described above, concentrated water 212, 21 is supplied from the reverse osmosis membrane device 202 and the membrane distiller 205.
3 occur respectively. The concentrated water 212, 213 is sent to the crystallizer 102 and separated into solid impurities 214 and high humidity gas 112. The separated solids 214 (i.e., the particulates 110 captured by the filter 111 in FIG.
3 and is separated into dry gas 113 and water 114. This dry gas 113 is returned to the crystallizer 102 for reuse, while the generated water 114 is returned to the reverse osmosis membrane device 20.
2 or returned to the raw water side of the membrane distiller 205, or used as treated water 116 as is.

FIG. 3 is a sectional view showing an example of the structure of the filter 111 on the output side of the crystallizer 102. In this filter, a cylindrical filter element 301 is fixed by flanges 302 and 303 to a cylindrical flow path through which high-humidity gas and particulates flow. The humid gas and particulates coming from upstream of the flow are filtered by the filter element 301, the particulates are captured by the filter element 301, and only the humid gas passes through the filter element 301. According to the configuration of this filter, only the filter element 301 can be replaced if the amount of captured particles increases. In addition, in this example, the cylindrical filter element is 1
Although only one filter element is shown, the effect will be further increased if a plurality of filter elements are attached.

FIG. 4 is a sectional view showing another example of the filter 111 on the output side of the crystallizer 102. This filter has flat filter elements 401, 402, 403.
, 404, and 405, and if the filter element 401 on the upstream side of the flow becomes clogged, the filter element 401 is removed and the next filter element 402 is used continuously. According to this example, by installing a plurality of filter elements in series, the replacement period of the filter elements can be extended, and the filter elements can be easily replaced by being pulled out laterally.

FIG. 5 shows still another example of the filter 111 on the output side of the crystallizer 102. The filter element 501 of this filter is wound into a roll, and if the portion of the filter element 501 in use is clogged with particulates, it can be replaced with a new filter element portion by winding the roll. For filters with flat filter element surfaces as shown in Figures 4 and 5, dried particles lack adhesion when immobilizing fine particles on the filter element, so Figure 5 shows a partially enlarged view. As shown in the figure, it is also necessary to form sticky, slightly moist particles 502 by controlling the temperature and flow rate of the gas.

FIG. 6 shows another example of the structure of the crystallizer 102. In this example, at least two or more filters 601 and 602 are installed in parallel instead of the one filter 111, so that when one filter 601 becomes clogged, the flow is switched to another filter 602 by a valve 603, While the clogged filter 601 is being replaced, another filter 602 is used to enable continuous operation of the device. Furthermore, in this embodiment, although the nozzle for the concentrated water 106 and the nozzle for the hot gas 107 are separate, the operation is the same as in the case of one nozzle 108 as shown in FIG.

In FIGS. 3, 4, 5, and 6, it is desirable to replace the filter by measuring the pressure loss before and after the filter and replacing it when the pressure loss exceeds a certain value.

FIG. 7 is a block diagram showing an example of the dehumidifying device 103 shown in FIGS. 1 and 2. In FIG. This device includes two cells 701 and 702 having hydrophobic porous membranes 705 and 705, respectively, and a pump 703 that circulates an absorption liquid 706 (for example, a lithium bromide aqueous solution) that easily absorbs water vapor between the cells. . High humidity gas 112 from crystallizer 102 flows on one side of cell 701 while contacting hydrophobic porous membrane 705 . An absorbent liquid 706 having a low water vapor pressure flows on the opposite side of the cell 701 , and water contained in the high-humidity gas is absorbed into the absorbent liquid 706 via the hydrophobic porous membrane 705 . Therefore, the gas 113 exiting from the cell 701 becomes a dry gas from which moisture has been removed, and is sent to the crystallization section 102 again. The absorbent liquid 706 that has absorbed moisture in the cell 701 is pumped to the other cell 702 by the pump 703.
sent to. Cooling water 708 having a water vapor pressure lower than that of the absorbing liquid 706 flows on the opposite side of the cell 702, and in the cell 702, the water vapor generated from the absorbing liquid 706 is absorbed by the cooling water 708 and becomes the water 114. becomes. By continuously performing such operations, the crystallizer 10
Moisture in the high humidity gas from 2 can be removed. In this example, a pump 70 is installed in the absorption liquid 706 line.
Although only 3 is installed, a heater is installed in the flow path that sends the absorption liquid from cell 701 to cell 702, and conversely, from cell 702 to cell 7.
By providing a cooler in the flow path that sends the absorption liquid to 01,
The rate of water vapor movement through membrane 705 can be increased.

FIG. 8 shows another example of the dehumidifying device 103. This dehumidification device is composed of a cooling section 801 and a gas-liquid separation section 802. The high-humidity gas 112 from the crystallizer 102 is first sent into the tube of the cooling unit 801 and cooled, and the moisture contained therein condenses on the inner wall of the tube. This condensed water and gas are directly sent to the gas-liquid separation section 802 by the action of the gas flow. The gas-liquid separation section 802 is constituted by a tube 804 made of a hydrophobic porous membrane, and only the gas passes through the hydrophobic porous membrane 804, whereby water 114 and gas 113 are separated. The separated dry gas 113 is released from a gas outlet 805, and the water 114 is released from a water outlet 806. By continuously performing such operations, moisture in the high humidity gas can be removed.

The apparatus shown in FIGS. 7 and 8 can be fully utilized not only for dehumidifying high-humidity gas from a crystallizer, but also for dehumidifying air inside a spacecraft or a space station.

[0023]

[Effects of the Invention] According to the present invention, concentrated water can be completely separated into impurities and water without using gravity, not only on the ground but also in zero gravity conditions such as in outer space, resulting in complete recycling. System configuration is easy.

[Brief explanation of the drawing]

[Fig. 1] A configuration diagram of an embodiment of water treatment equipment according to the present invention.

[Figure 2] A configuration diagram showing the above water treatment equipment in more detail.

[Fig. 3] A cross-sectional view showing an example of a filter used in the crystallizer of the present invention.

[Figure 4] Cross-sectional view showing another example of the same filter

[Figure 5
】Cross-sectional view showing yet another example of the same filter

FIG. 6 is a diagram showing another example of the structure of the crystallizer according to the present invention.

[Fig. 7] A diagram showing an example of a dehumidification device in the present invention.

[Figure 8
】A diagram showing another example of the dehumidification device

[Explanation of symbols]

101...Water treatment equipment
102...Crystallizer 103...Dehumidifier
104...Gas heater

Claims (8)

[Claims] Claims: 1. A crystallization unit that atomizes concentrated water containing concentrated impurities and vaporizes the atomized water by contacting it with warm gas to produce a high-humidity gas in which the impurities are suspended as particulate solids; 1. A water treatment facility comprising: a crystallizer having: a filter that separates the particulate solids generated in the crystallization section from the high-humidity gas. 2. The water treatment equipment according to claim 1, further comprising a dehumidifier that separates the high humidity gas into moisture and dry gas after separating the particulate solids. 3. The concentrated water is concentrated water from a water treatment device other than the crystallizer, and the water separated by the dehumidification device is used again as raw water for the water treatment device and separated by the dehumidification device. 3. The water treatment facility according to claim 2, wherein said dry gas is recycled as warm gas in said crystallizer. 4. The crystallization section of the crystallizer includes a cell and a nozzle provided in the cell that sprays the concentrated water together with the warm gas, or a nozzle that sprays the concentrated water and a nozzle of the nozzle. 4. The water treatment equipment according to claim 1, further comprising a nozzle located nearby that injects the warm gas. 5. The water treatment equipment according to claim 1, wherein at least two or more filters of the crystallizer are installed in parallel or in series. 6. The dehumidifying device is configured to bring the high-humidity gas into contact with a hygroscopic aqueous solution directly or through a hydrophobic porous membrane, thereby causing the aqueous solution to absorb moisture in the gas. Claim 2 or 3 characterized in that
Water treatment equipment as described. 7. The dehumidification device brings the aqueous solution after absorbing moisture in the high-humidity gas into contact with water or gas having a lower water vapor pressure than the aqueous solution, either directly or via a hydrophobic porous membrane. 7. The water treatment equipment according to claim 6, wherein the water treatment equipment is configured to remove water from the aqueous solution. 8. The dehumidification device comprises means for cooling the high-humidity gas to condense moisture in the gas, and means for separating the condensed water and the gas using a hydrophobic porous membrane. The water treatment equipment according to claim 2 or 3, characterized in that: