GB2368808A - A bathing pool filtration system - Google Patents
A bathing pool filtration system Download PDFInfo
- Publication number
- GB2368808A GB2368808A GB0027727A GB0027727A GB2368808A GB 2368808 A GB2368808 A GB 2368808A GB 0027727 A GB0027727 A GB 0027727A GB 0027727 A GB0027727 A GB 0027727A GB 2368808 A GB2368808 A GB 2368808A
- Authority
- GB
- United Kingdom
- Prior art keywords
- water
- pool
- wash water
- filter means
- filtration system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000001914 filtration Methods 0.000 title claims abstract description 48
- 238000003287 bathing Methods 0.000 title claims abstract description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 163
- 239000012535 impurity Substances 0.000 claims abstract description 25
- 239000002699 waste material Substances 0.000 claims abstract description 15
- 238000005406 washing Methods 0.000 claims abstract description 8
- 238000007599 discharging Methods 0.000 claims abstract description 3
- 238000009434 installation Methods 0.000 claims description 7
- 238000001223 reverse osmosis Methods 0.000 claims description 7
- 150000003839 salts Chemical class 0.000 claims description 5
- 239000007787 solid Substances 0.000 claims description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 3
- 239000011780 sodium chloride Substances 0.000 claims description 3
- 238000011144 upstream manufacturing Methods 0.000 claims 2
- 239000013505 freshwater Substances 0.000 abstract description 7
- 238000011001 backwashing Methods 0.000 abstract description 6
- 230000001143 conditioned effect Effects 0.000 abstract 1
- 239000004576 sand Substances 0.000 description 8
- 238000000034 method Methods 0.000 description 5
- 239000000126 substance Substances 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000002169 hydrotherapy Methods 0.000 description 2
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 238000010923 batch production Methods 0.000 description 1
- 239000003139 biocide Substances 0.000 description 1
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 description 1
- 229910052794 bromium Inorganic materials 0.000 description 1
- 239000000872 buffer Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 239000008396 flotation agent Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000008213 purified water Substances 0.000 description 1
- 239000012629 purifying agent Substances 0.000 description 1
- 239000002910 solid waste Substances 0.000 description 1
- 230000001954 sterilising effect Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- 230000009182 swimming Effects 0.000 description 1
- 230000001225 therapeutic effect Effects 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D24/00—Filters comprising loose filtering material, i.e. filtering material without any binder between the individual particles or fibres thereof
- B01D24/02—Filters comprising loose filtering material, i.e. filtering material without any binder between the individual particles or fibres thereof with the filter bed stationary during the filtration
- B01D24/10—Filters comprising loose filtering material, i.e. filtering material without any binder between the individual particles or fibres thereof with the filter bed stationary during the filtration the filtering material being held in a closed container
- B01D24/105—Filters comprising loose filtering material, i.e. filtering material without any binder between the individual particles or fibres thereof with the filter bed stationary during the filtration the filtering material being held in a closed container downward filtration without specifications about the filter material supporting means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D24/00—Filters comprising loose filtering material, i.e. filtering material without any binder between the individual particles or fibres thereof
- B01D24/46—Regenerating the filtering material in the filter
- B01D24/4631—Counter-current flushing, e.g. by air
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D36/00—Filter circuits or combinations of filters with other separating devices
- B01D36/02—Combinations of filters of different kinds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D37/00—Processes of filtration
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/441—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by reverse osmosis
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/42—Nature of the water, waste water, sewage or sludge to be treated from bathing facilities, e.g. swimming pools
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/04—Flow arrangements
- C02F2301/043—Treatment of partial or bypass streams
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2303/00—Specific treatment goals
- C02F2303/16—Regeneration of sorbents, filters
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
A filtration system for a bathing pool 10 comprises a primary water filtration circuit including the pool and pool water filter 16, 18 and means for washing impurities from the pool water filter with wash water which includes a source of fresh water 48 distinct from the pool water. Preferably a secondary water filtration circuit for the wash water includes a wash water filter 40, freshwater 48 for removing impurities from the wash water filter, a conduit 20 for discharging said impurities to waste and a holding tank 44 and pump 46 for reusing at least some of the wash water in the pool water filter after removal of the impurities by the wash water filter. Preferably, the wash water for the pool water filter is not discharged directly to waste but is treated in a secondary water filtration circuit and at least some of the treated water is re-used. Advantageously expensive conditioned pool water is not wasted on backwashing the pool filter.
Description
FILTRATION SYSTEM
This invention relates to a filtration system for a bathing pool, such as a swimming pool or hydrotherapy pool.
A filtration circuit for a bathing pool typically includes the pool and a filter, with water conduits between the two, and appropriate pump means. Pool water flows through a filter medium which extracts impurities before the water is returned to the pool. A typical filter medium is sand. The pool water passes downwardly through a sand bed, and solids suspended in the water are trapped in the bed. After a while, the filter bed needs to be purged of the accumulated impurities. This is typically achieved by diverting the flow of pool water to the bottom of the sand bed, and using an up-flow of the water to backwash the filter and carry the impurities away to waste. The sand is sufficiently dense not to be carried away with the impurities and wash water.
It is an object of the present invention to provide an alternative filtration system, and in particular one that is more economical with water, especially with pool water.
In accordance with one aspect of the invention, there is provided a filtration system for a bathing pool comprising: a) a primary water filtration circuit including the pool and pool water filter means, for pool water;
b) means for washing impurities from the pool water filter means with wash water ; wherein the means for washing impurities from the pool water filter means includes a source of fresh water distinct from the pool water. The fresh water may be from a mains supply, or partly from a mains supply and partly recycled, or wholly recycled and topped up only when necessary.
It should be relatively pure, compared with the pool water. It should contain less, and preferably substantially no, suspended matter. Solutes in the pool water are likely to be chemical purifying agents (sterilising agents and biocides such as chlorine, bromine, or slow release sources thereof), pH-maintaining agents (acidic or alkaline species and buffers) or salts (therapeutic spa salts and flotation agents).
Heretofore, it has been accepted that pool water should be used for backwashing the pool water filters to waste.
The present invention has the potential to realise great environmental and economic benefits in comparison.
In a preferred aspect, the filtration system comprises means for washing impurities from the pool water filter means which includes a secondary water filtration circuit for the wash water, including: c) wash water filter means, for the wash water; d) means for removing impurities from the wash water filter means;
e) means for discharging said impurities to waste ; and f) means for re-using at least some of the wash water in the pool water filter means after removal of said impurities by the wash water filter means.
Accordingly, the wash water for the pool water filter (the pool water filter means) is not discharged directly to waste but on the contrary is treated in a secondary water filtration circuit, and at least some of the treated water is then re-used as wash water. This gives a direct benefit in that this water is discharged to waste when backwashing the pool water filter.
Additional benefits are attainable because it is not necessary to use pool water to effect the pool filter backwash. The pool water may be heated water, and it may be saline water which may contain over 10% by weight of dissolved salts. The water will have been chemically treated and purified and represents a substantial investment in heat and solutes.
The wash water in the secondary water circuit can be recirculated and reconditioned, although some may need to be removed to dispose of dissolved impurities that cannot be removed by filtration. The wash water filter means may be adapted to remove both solid and solute impurities from the wash water. The wash water filter means may be associated with means for removing accumulated impurities with clean water. In a particularly preferred aspect of the invention, the wash water filter means comprises a reverse osmosis installation.
The secondary water filtration circuit may include a
first holding tank for used wash water from the pool water filter means before the wash water filter means.
The secondary water filtration circuit may also include a second holding tank for purified wash water from the wash water filter means before its re-use in the pool water filter means. Wash water top-up means may be provided to supply fresh top-up water to the second holding tank.
One embodiment of the invention is described by way of example in the accompanying drawings, in which:
Figure 1 is a diagram depicting a filtration system for a bathing pool in accordance with the prior art; and
Figure 2 is a diagram depicting a filtration system for a bathing pool in accordance with the invention.
In the prior art system illustrated in Figure 1, water from a bathing pool 10 is removed from the pool through pool outlet conduit 12 by pump 14. A filter chamber 16 contains, in its lower part, a water permeable filter bed 18 of sand. A first water pipe 32 opens into the top of the chamber, above the filter bed, and a second water pipe 34 opens into the bottom of the chamber, below the filter bed.
Pool water from conduit 12 is passed through filter chamber 16 by pump 14 in accordance with the settings of the various valves or stopcocks 22,24, 26 and 28 in the pipework around the filter chamber. In order to normally filter pool water, valves 22 and 28 are open while valves 24 and 26 are closed. In this condition, pool water passes downwardly through the filter chamber, entering by pipe 32 and leaving by pipe 34, and returns to the pool
through pool inlet conduit 30. Solid waste materials remain behind on the sand filter bed 18.
In order to backwash the filter to clean it, valves 22 and 28 are closed and valves 24 and 26 are opened. In this condition, pump 14 pumps pool water upwardly through the filter bed and away to waste through waste conduit 20.
A filtration system in accordance with the invention is shown, as one example only, in Figure 2. This has a primary water filtration circuit and a secondary water filtration circuit. The primary circuit retains the principal elements of the prior art filtration circuit, for filtration purposes, but not for backwashing purposes. Thus the primary circuit includes pool 10, pool outlet conduit 12, primary water circulation pump 14, filter chamber 16 containing the sand filter bed 18 with upper and lower water pipes 32 and 24, and valve 28 before the pool inlet conduit 30 conducts the filtered water back to the pool.
However, the system illustrated in Figure 2 also has a secondary water filtration circuit which shares the filter chamber 16 and its upper and lower water conduits 32 and 34, and also includes wash water filter means 40, in this case a reverse osmosis installation, a dirty wash water holding tank 42, a purified wash water holding tank 44, and a secondary water circulation pump 46. Because the reverse osmosis process is a relatively slow process, while the filter backwashing process is a relatively rapid batch process in which a large volume of water passes through the filter chamber, the two holding tanks are desirable. For example, if pool 10 is a circular
pool 9m in diameter with a water depth of 1. 35m, the backwashing of filter bed 18 may require 600 litres of water to be passed rapidly from purified wash water holding tank 44 to the dirty wash water holding tank 42.
In the reverse osmosis installation 40, due to the nature of this process, a continuous waste water flow is produced containing not only solids extracted from the secondary water filtration circuit, but also solutes that may be accumulating in the wash water. Typically, about 20% of the water flowing through the reverse osmosis installation is discarded as waste through conduit 20.
The installation 40 may include a bypass, or the water may pass through without the osmosis process being run, if the wash water only needs to be purified at intervals longer than the intervals between pool filter washings.
A fresh water inlet 48 is provided between the wash water filter means 40 and the purified water holding tank 44.
This fresh water is provided for two purposes. One is to top up the system as the 20% of circulating water is extracted, and the other is to provide cleaning or backwash water for the wash water filter means, as may be necessary. For such a backwash, water would be admitted through inlet 40 and discharged to waste through waste conduit 20.
The different paths taken by the water in the system, when pumped by pumps 14 and 46, are determined by the various valves or stopcocks. Valves 50,52, 54,56 and 58 are located at appropriate positions in the secondary water filtration circuit. Valve 60 is located in the primary water filtration circuit with valve 28. Valve 60
opens or closes the fresh water inlet 48, and, as in the prior art, valve 24 controls waste conduit 20.
Although a reverse osmosis installation is shown as filter means 40, other alternatives are possible, including another sand filter or the like.
It should be noted that the primary water filtration circuit will also include, normally in the return leg after valve 28, the usual balance tanks, chemical dosing and sterilisation facilities. These are omitted from the drawings and from the description of the invention for the sake of clarity.
By means of the system described, the water in the pool 10 can be filtered frequently, and the pool filter backwashed frequently, without undue loss of valuable heated pool water with its chemical content, including salts. It is preferred that the pool filter throughput rate is such that the whole volume of pool water is filtered in less than one hour. The pool may in this way economically support intensive use as a hydrotherapy pool.
Claims (15)
- CLAIMS 1 A filtration system for a bathing pool comprising: a) a primary water filtration circuit including the pool and pool water filter means, for pool water; b) means for washing impurities from the pool water filter means with wash water; wherein the means for washing impurities from the pool water filter means includes a source of fresh wash water distinct from the pool water.
- 2 A filtration system according to claim 1 wherein the pool water is heated water and/or saline water.
- 3 A filtration system according to claim 2 wherein the pool water is saline water which contains over 10% by weight of dissolved salts.
- 4 A filtration system according to any one of the preceding claims wherein the said source includes a holding tank upstream of the pool water filter means for wash water from a mains supply.
- 5 A filtration system according to any one of claims 1 to 3 wherein the means for washing impurities from the pool water filter means includes a holding tank downstream of the pool water filter means for used wash water before discharge to waste.
- 6 A filtration system according to claim 4 and claim 5 including means for returning water from the downstream holding tank to the upstream holding tank.
- 7 A filtration system according to claim 6 wherein the means for returning water includes wash water filter means.
- 8 A filtration system according to any one of claims 1 to 3 wherein the said source includes a secondary water filtration circuit for the wash water, including: c) wash water filter means, for the wash water; d) means for removing impurities from the wash water filter means; e) means for discharging said impurities to waste; and f) means for re-using at least some of the wash water in the pool water filter means after removal of said impurities by the wash water filter means.
- 9 A filtration system according to claim 8 wherein the secondary water filtration circuit includes a first holding tank for used wash water from the pool water filter means before the wash water filter means.
- 10 A filtration system according to claim 8 or 9 wherein the secondary water filtration circuit may also include a second holding tank for purified wash water from the wash water filter means before its re-use in the pool water filter means.
- 11 A filtration system according to any one of claims 8 to 10 including wash water top-up means to supply fresh top-up water to the second holding tank.
- 12 A filtration system according to any one of the preceding claims wherein the wash water filter means is adapted to remove both solid and solute impurities from the wash water.
- 13 A filtration system according to any one of the preceding claims wherein the wash water filter means is associated with means for removing accumulated impurities with clean water.
- 14 A filtration system according to any one of the preceding claims wherein the wash water filter means comprises a reverse osmosis installation.
- 15 A filtration system substantially as herein described with reference to Figure 2 of the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB0027727A GB2368808B (en) | 2000-11-14 | 2000-11-14 | Filtration system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB0027727A GB2368808B (en) | 2000-11-14 | 2000-11-14 | Filtration system |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB0027727D0 GB0027727D0 (en) | 2000-12-27 |
| GB2368808A true GB2368808A (en) | 2002-05-15 |
| GB2368808B GB2368808B (en) | 2004-01-14 |
Family
ID=9903112
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB0027727A Expired - Fee Related GB2368808B (en) | 2000-11-14 | 2000-11-14 | Filtration system |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2368808B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1400272A1 (en) * | 2002-08-27 | 2004-03-24 | Maax, Inc. | Self-cleaning water filtration system and method |
| FR2854625A1 (en) * | 2003-05-06 | 2004-11-12 | Pomes Darre S A Ets | Device for sterilizing ponds and pools by incorporating microbubbles into the water comprises a microperforated pipe, a bed of coarse drainage material, a sheet of geotextile and a bed of silica sand |
| WO2009103101A1 (en) * | 2008-02-22 | 2009-08-27 | Minnova Mineralien Handelsgesellschaft .M.B.H. | Filter arrangement |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1258090A (en) * | 1969-05-19 | 1971-12-22 | ||
| US3932278A (en) * | 1974-02-15 | 1976-01-13 | Sterling Drug Inc. | Filter cleaning method |
| GB1446582A (en) * | 1973-06-28 | 1976-08-18 | Craster T Y | Filter tank assembly |
-
2000
- 2000-11-14 GB GB0027727A patent/GB2368808B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1258090A (en) * | 1969-05-19 | 1971-12-22 | ||
| GB1446582A (en) * | 1973-06-28 | 1976-08-18 | Craster T Y | Filter tank assembly |
| US3932278A (en) * | 1974-02-15 | 1976-01-13 | Sterling Drug Inc. | Filter cleaning method |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1400272A1 (en) * | 2002-08-27 | 2004-03-24 | Maax, Inc. | Self-cleaning water filtration system and method |
| FR2854625A1 (en) * | 2003-05-06 | 2004-11-12 | Pomes Darre S A Ets | Device for sterilizing ponds and pools by incorporating microbubbles into the water comprises a microperforated pipe, a bed of coarse drainage material, a sheet of geotextile and a bed of silica sand |
| WO2009103101A1 (en) * | 2008-02-22 | 2009-08-27 | Minnova Mineralien Handelsgesellschaft .M.B.H. | Filter arrangement |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2368808B (en) | 2004-01-14 |
| GB0027727D0 (en) | 2000-12-27 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20161114 |