CA1148934A - Waste water heat recovery system - Google Patents
Waste water heat recovery systemInfo
- Publication number
- CA1148934A CA1148934A CA000375094A CA375094A CA1148934A CA 1148934 A CA1148934 A CA 1148934A CA 000375094 A CA000375094 A CA 000375094A CA 375094 A CA375094 A CA 375094A CA 1148934 A CA1148934 A CA 1148934A
- Authority
- CA
- Canada
- Prior art keywords
- hot water
- heat exchanger
- water
- heat
- waste
- 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.)
- Expired
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D17/00—Domestic hot-water supply systems
- F24D17/0005—Domestic hot-water supply systems using recuperation of waste heat
- F24D17/001—Domestic hot-water supply systems using recuperation of waste heat with accumulation of heated water
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D2200/00—Heat sources or energy sources
- F24D2200/16—Waste heat
- F24D2200/20—Sewage water
-
- 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
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/18—Domestic hot-water supply systems using recuperated or waste heat
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Instantaneous Water Boilers, Portable Hot-Water Supply Apparatuses, And Control Of Portable Hot-Water Supply Apparatuses (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
An improvement is provided in a system comprising (i) a source of fresh hot water, (ii) a source of waste hot water fed from the fresh hot water, and (iii) a drain for discharging the waste hot water. The improve-ment comprises a hot water heat recovery system interposed between the source of waste hot water and the drain, comprising: (a) a water/water heat exchanger; (b) conduit means automatically controllably continuously and selectively passing the waste hot water to the heat exchanger before the waste hot water passes to the drain; (c) conduit means automatically con-trollably continuously selectively passing the cool fresh water to the heat exchanger to be preheated and pipe means connecting to said heat exchanger to said shource of fresh hot water and for continuously withdrawing the preheated water from the heat exchanger, and contuit means automatically controllably, continuously and selectively simultaneously passing the waste hot water to the heat exchanger in heat exchange contact only with the cool fresh water; and (d) temperature control means associated with the conduit means to shunt the waste hot water from the heat exchanger to the drain and simultaneously to shunt the flow of cool fresh water from the heat exchan-ger when the water temperature drops below a selected value. By these means, the waste heat in hot water is recovered and is used to preheat in-coming cool water before it proceeds to the hot water heater and the waste hot water does not enter the heat exchanger unless it is hot enough. Thus plugging of the heat exchanger by sedimentation and precipitation of solids out of cooler water is minimized.
An improvement is provided in a system comprising (i) a source of fresh hot water, (ii) a source of waste hot water fed from the fresh hot water, and (iii) a drain for discharging the waste hot water. The improve-ment comprises a hot water heat recovery system interposed between the source of waste hot water and the drain, comprising: (a) a water/water heat exchanger; (b) conduit means automatically controllably continuously and selectively passing the waste hot water to the heat exchanger before the waste hot water passes to the drain; (c) conduit means automatically con-trollably continuously selectively passing the cool fresh water to the heat exchanger to be preheated and pipe means connecting to said heat exchanger to said shource of fresh hot water and for continuously withdrawing the preheated water from the heat exchanger, and contuit means automatically controllably, continuously and selectively simultaneously passing the waste hot water to the heat exchanger in heat exchange contact only with the cool fresh water; and (d) temperature control means associated with the conduit means to shunt the waste hot water from the heat exchanger to the drain and simultaneously to shunt the flow of cool fresh water from the heat exchan-ger when the water temperature drops below a selected value. By these means, the waste heat in hot water is recovered and is used to preheat in-coming cool water before it proceeds to the hot water heater and the waste hot water does not enter the heat exchanger unless it is hot enough. Thus plugging of the heat exchanger by sedimentation and precipitation of solids out of cooler water is minimized.
Description
~8~3~
This invention relates to a heat dissipating system for recover-ing heat from waste water.
Most heat dissipating systems are merely design~d for cooling viscous liquids. For example, Canadian Patent No. 441,887 issued June 3, 1947 to Imperial Chemical Industries, provides such a system which includes automatically operated by-pass valves in conjunction with auto-matically controlled shutters or louvres arranged to control the flow of the external cooling medium.
Canadian Patent No. 453,673 issued December 28, 1948 to Imperial Chemical Industries, provides a cooling device in which the hot fluid to be cooled can pass through all or some of interconnected cooling passages.
Canadian Patent No. 489,632 issued December 29, 1959 to The Coleman Lamp & Stove Company Limited provides method and means for con-trolling heat transfer in furnace casings in which heat reflective areas are provided to avoid localization of high temperatures.
; Canadian Patent No. 689,184 issued June 23, 1964 to Sulzer Frères provides a heat exchanger system and method in which the rates of flow of heat exchanging fluid is dependent on the temperature of the heat exchanging fluid leaving the heat exchanger.
Canadian Patent No. 737,807 issued July 5, 1966 to Vorcan Asso-ciates provides a temperature control system having main heat exchange lines and bypass heat exchange lines controlled in order to provide a constant temperature supply fluid.
Canadian Patent No. 849,946 issued August 25, 1970 to A.B.
Svensk Flaktfabriken provides a method for recovering heat from an air-water vapour mixture from a dissolved receiving melt which provides generating steam from the melt and then using the steam in heat exchange relation to condense the steam and simultaneously to heat the water in the heat exchanger.
. ~
.
~893~
Canadian Patent NO. 1,026,31~ issued February 14, 1978 to Hayden Trans-Cooler Inc. provides a heat exchange valve system having pri-mary and bypass valve functions.
Finally, Canadian Patent No. 1,078,823 issued June 3, 1980 to T.A. Thoren provides a method for the utili~ation of the heat energy of sewage by heating air with the waste heat from the sewage and then recover-ing the heat in the hot air by an air/air heat exchanger.
Thus, while heat recovery systems have been proposed, none has been devised to recover the sensible heat rom waste hot water and to re-cycle and use that recovered heat to heat additional hot water.
Accordingly an object of a broad aspect of this invention is to provide a system to recover the sensible heat from waste hot water and to use such recovered heat to preheat cool water before such cool water is ?
passed to a hot water heater to be heated.
By a broad aspect of this invention, an improvement is provided in a system comprising ~i) a source of fresh hot water, (ii) a source of waste hot water fed from the fresh hot water, and (iii) a drain for dis-charging the waste hot water, a hot water heat recovery system interposed between the source of waste hot water and the drain comprising: (a) a water/water heat exchanger; (b) conduit means automatically controllably continuously and selectively passing the waste hot water to the heat ex-changer before the waste hot water passes to the drain; (c) conduit means automatically controllably continuously selectively passing the cool fresh - water to the heat exchanger to be preheated and pipe means connecting to the heat exchanger to the source of fresh hot water and for continuously withdrawing the preheated water from the heat exchanger, and conduit means ~- automatically controllably, continuously and selectively simultaneously passing the waste hot water to the heat exchanger in heat exchange contact
This invention relates to a heat dissipating system for recover-ing heat from waste water.
Most heat dissipating systems are merely design~d for cooling viscous liquids. For example, Canadian Patent No. 441,887 issued June 3, 1947 to Imperial Chemical Industries, provides such a system which includes automatically operated by-pass valves in conjunction with auto-matically controlled shutters or louvres arranged to control the flow of the external cooling medium.
Canadian Patent No. 453,673 issued December 28, 1948 to Imperial Chemical Industries, provides a cooling device in which the hot fluid to be cooled can pass through all or some of interconnected cooling passages.
Canadian Patent No. 489,632 issued December 29, 1959 to The Coleman Lamp & Stove Company Limited provides method and means for con-trolling heat transfer in furnace casings in which heat reflective areas are provided to avoid localization of high temperatures.
; Canadian Patent No. 689,184 issued June 23, 1964 to Sulzer Frères provides a heat exchanger system and method in which the rates of flow of heat exchanging fluid is dependent on the temperature of the heat exchanging fluid leaving the heat exchanger.
Canadian Patent No. 737,807 issued July 5, 1966 to Vorcan Asso-ciates provides a temperature control system having main heat exchange lines and bypass heat exchange lines controlled in order to provide a constant temperature supply fluid.
Canadian Patent No. 849,946 issued August 25, 1970 to A.B.
Svensk Flaktfabriken provides a method for recovering heat from an air-water vapour mixture from a dissolved receiving melt which provides generating steam from the melt and then using the steam in heat exchange relation to condense the steam and simultaneously to heat the water in the heat exchanger.
. ~
.
~893~
Canadian Patent NO. 1,026,31~ issued February 14, 1978 to Hayden Trans-Cooler Inc. provides a heat exchange valve system having pri-mary and bypass valve functions.
Finally, Canadian Patent No. 1,078,823 issued June 3, 1980 to T.A. Thoren provides a method for the utili~ation of the heat energy of sewage by heating air with the waste heat from the sewage and then recover-ing the heat in the hot air by an air/air heat exchanger.
Thus, while heat recovery systems have been proposed, none has been devised to recover the sensible heat rom waste hot water and to re-cycle and use that recovered heat to heat additional hot water.
Accordingly an object of a broad aspect of this invention is to provide a system to recover the sensible heat from waste hot water and to use such recovered heat to preheat cool water before such cool water is ?
passed to a hot water heater to be heated.
By a broad aspect of this invention, an improvement is provided in a system comprising ~i) a source of fresh hot water, (ii) a source of waste hot water fed from the fresh hot water, and (iii) a drain for dis-charging the waste hot water, a hot water heat recovery system interposed between the source of waste hot water and the drain comprising: (a) a water/water heat exchanger; (b) conduit means automatically controllably continuously and selectively passing the waste hot water to the heat ex-changer before the waste hot water passes to the drain; (c) conduit means automatically controllably continuously selectively passing the cool fresh - water to the heat exchanger to be preheated and pipe means connecting to the heat exchanger to the source of fresh hot water and for continuously withdrawing the preheated water from the heat exchanger, and conduit means ~- automatically controllably, continuously and selectively simultaneously passing the waste hot water to the heat exchanger in heat exchange contact
- 2 -'' 1 ~":` A
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.
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.
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.- . ...
~8~34 only with the cool fresh water; and (d) temperature control means associa-ted with the conduit means to shunt the waste hot water from the heat ex-changer to the drain and simultaneously to shunt the flow of cool fresh water from the heat exchanger when the water temperature drops below a selected value.
By a variant thereof, the source of waste hot water is an automatic dishwaster, and the heat exchanger is a separate and distinct unit from the dishwasher By another variant, the source of waste hot water is an auto-matic clothes washer, and the heat exchanger is a separate and distinct unit from the clothes washer.
By yet another variant, the source of fresh hot water is a hot watér heater, and the heat exchanger is a separate and distinct unit from the hot water heater.
By a variation thereof, the heat exchanger is intimately associ-ated with the automatic dishwasher, or automatic clothes washer or hot wa-ter heater.
By another variant, all the conduit means are wrapped with heat insulating material to minimize heat loss therefrom.
. By yet a further variant, the temperature control means is ad-justed to operate when the temperature of the waste hot water falls below ` 90F.
In the accompanying drawing, the single figure is a diagrammatic representation of the system of an aspect of this invention.
In a conventional system, a source of hot water, i.e., a hot water tank 11 is fed with cold water through water inlet 12 and, after being heated in tank 11, emerges as hot water in line 13 and is fed to a washer, i.e., an automatic washing machine or an automatic dishwasher 14.
.
~ - 3 -.:
~8~3~ :
The waste hot water passes through outlet lines 15 and l5a to drain 16.
In the embodiment of this invention shown, cool water bypasses hot water tank 11 in line 22 and enters a water/water heat exchanger 23 at 24. Waste hot water in line 15 enters heat exchanger 23 at 25. The countercurrent separate water flows permit heat to pass from the waste hot water to the fresh cool water. Thus, the fresh water outlet line 26 com-prises preheated water and this merges with fresh cool water in line 12.10 Thus, the water entering hot water tank 11 is warm water, rather than cold water. Similarly, waste water leaving via line l5a is warm water rather than hot water, and so the water entering drain 16 is warm. All :::
.
'.
:
.
.. ~,~ . . .
.
. . . . ~ .. ~ . .
.- . ...
~8~34 only with the cool fresh water; and (d) temperature control means associa-ted with the conduit means to shunt the waste hot water from the heat ex-changer to the drain and simultaneously to shunt the flow of cool fresh water from the heat exchanger when the water temperature drops below a selected value.
By a variant thereof, the source of waste hot water is an automatic dishwaster, and the heat exchanger is a separate and distinct unit from the dishwasher By another variant, the source of waste hot water is an auto-matic clothes washer, and the heat exchanger is a separate and distinct unit from the clothes washer.
By yet another variant, the source of fresh hot water is a hot watér heater, and the heat exchanger is a separate and distinct unit from the hot water heater.
By a variation thereof, the heat exchanger is intimately associ-ated with the automatic dishwasher, or automatic clothes washer or hot wa-ter heater.
By another variant, all the conduit means are wrapped with heat insulating material to minimize heat loss therefrom.
. By yet a further variant, the temperature control means is ad-justed to operate when the temperature of the waste hot water falls below ` 90F.
In the accompanying drawing, the single figure is a diagrammatic representation of the system of an aspect of this invention.
In a conventional system, a source of hot water, i.e., a hot water tank 11 is fed with cold water through water inlet 12 and, after being heated in tank 11, emerges as hot water in line 13 and is fed to a washer, i.e., an automatic washing machine or an automatic dishwasher 14.
.
~ - 3 -.:
~8~3~ :
The waste hot water passes through outlet lines 15 and l5a to drain 16.
In the embodiment of this invention shown, cool water bypasses hot water tank 11 in line 22 and enters a water/water heat exchanger 23 at 24. Waste hot water in line 15 enters heat exchanger 23 at 25. The countercurrent separate water flows permit heat to pass from the waste hot water to the fresh cool water. Thus, the fresh water outlet line 26 com-prises preheated water and this merges with fresh cool water in line 12.10 Thus, the water entering hot water tank 11 is warm water, rather than cold water. Similarly, waste water leaving via line l5a is warm water rather than hot water, and so the water entering drain 16 is warm. All :::
.
'.
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. .
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lines conduiting warm water, i.e., 13, 15, 25, 26 and 12 are wrapped in heat insulation material to minimi~e heat loss.
A valve system 27 i5 provided which senses the temperature of the water in line 15. If the temperature is sensed to be above a certain value, i.e., about 90 F., water passes to heat exchanger 23, If, however, the water temperature is below that level, the water passes through bypass line 28 to drain 16.
'.
. .
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lines conduiting warm water, i.e., 13, 15, 25, 26 and 12 are wrapped in heat insulation material to minimi~e heat loss.
A valve system 27 i5 provided which senses the temperature of the water in line 15. If the temperature is sensed to be above a certain value, i.e., about 90 F., water passes to heat exchanger 23, If, however, the water temperature is below that level, the water passes through bypass line 28 to drain 16.
'.
Claims (8)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In a system comprising (i) a source of fresh hot water, (ii) a source of waste hot water, and (iii) a drain for discharging said waste hot water, a hot water heat recovery system interposed between said source of waste hot water and said drain comprising:
(a) a water/water heat exchanger;
(b) conduit means automatically controllably continuously and selectively passing said waste hot water to said heat exchanger before said waste hot water passes to said drain;
(c) conduit means automatically controllably continuously selectively passing said cool fresh water to said heat exchanger to be preheated and pipe means connecting to said heat exchanger to said source of fresh hot water and for continuously withdrawing said preheated water from said heat exchanger, and conduit means automatical-ly controllably, continuously and selectively simultane-ously passing said waste hot water to said heat exchanger in heat exchange contact only with said cool fresh water;
and (d) temperature control means associated with said conduit means to shunt said waste hot water from said heat ex-changer to said drain and simultaneously to shunt the flow of cool fresh water from said heat exchanger when the water temperature drops below a selected value.
(a) a water/water heat exchanger;
(b) conduit means automatically controllably continuously and selectively passing said waste hot water to said heat exchanger before said waste hot water passes to said drain;
(c) conduit means automatically controllably continuously selectively passing said cool fresh water to said heat exchanger to be preheated and pipe means connecting to said heat exchanger to said source of fresh hot water and for continuously withdrawing said preheated water from said heat exchanger, and conduit means automatical-ly controllably, continuously and selectively simultane-ously passing said waste hot water to said heat exchanger in heat exchange contact only with said cool fresh water;
and (d) temperature control means associated with said conduit means to shunt said waste hot water from said heat ex-changer to said drain and simultaneously to shunt the flow of cool fresh water from said heat exchanger when the water temperature drops below a selected value.
2. The system of claim 1 wherein said source of waste hot water is an automatic dishwasher and wherein said heat exchanger is a separate and distinct unit from said dishwasher.
3. The system of claim 1 wherein said source of waste hot water is an automatic clothes washer and wherein said heat exchanger is a separ-ate and distinct unit from said clothes washer.
4. The system of claims 1, 2 or 3 wherein said source of fresh hot water is a hot water heater, and wherein said heat exchanger is a separate and distinct unit from said hot water heater.
5. The system of claims 1, 2 or 3 wherein said heat exchanger is intimately associated with said automatic dishwasher, or automatic clothes washer or hot water heater.
6. The system of claims 1, 2 or 3 wherein said source of fresh hot water is a hot water heater, and wherein said heat exchanger is a separate and distinct unit from said hot water heater and wherein said heat exchanger is intimately associated with said automatic dishwasher, or automatic clothes washer or hot water heater.
7. The system of claims 1, 2 or 3 wherein all said conduit mean are wrapped with heat insulating material to minimize heat loss therefrom.
8. The system of claims 1, 2 or 3 wherein said temperature con-trol means is adjusted to operate when the temperature of said waste hot water falls below 90°F.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000375094A CA1148934A (en) | 1981-04-09 | 1981-04-09 | Waste water heat recovery system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000375094A CA1148934A (en) | 1981-04-09 | 1981-04-09 | Waste water heat recovery system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1148934A true CA1148934A (en) | 1983-06-28 |
Family
ID=4119695
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000375094A Expired CA1148934A (en) | 1981-04-09 | 1981-04-09 | Waste water heat recovery system |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1148934A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5626102A (en) * | 1996-03-14 | 1997-05-06 | Nir; Ari | Heat recovery system for a boiler and a boiler provided therewith |
| US8176926B2 (en) * | 2008-03-26 | 2012-05-15 | Meiko Maschinenbau Gmbh & Co. Kg | Batch dishwasher with waste water heat recovery |
| WO2012061945A1 (en) * | 2010-11-10 | 2012-05-18 | Ambercore Software Inc. | System and method for object searching using spatial data |
| FR2987670A1 (en) * | 2012-03-05 | 2013-09-06 | Energy Harvesting Tech | DEVICE FOR THE RECOVERY OF THERMAL ENERGY FROM A FLOW OF WASTE WATER |
| US10633838B2 (en) | 2013-03-05 | 2020-04-28 | Energy Harvesting Tech | Device for recovering thermal energy from a flow of waste water |
-
1981
- 1981-04-09 CA CA000375094A patent/CA1148934A/en not_active Expired
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5626102A (en) * | 1996-03-14 | 1997-05-06 | Nir; Ari | Heat recovery system for a boiler and a boiler provided therewith |
| WO1997034107A1 (en) * | 1996-03-14 | 1997-09-18 | Ari Nir | Heat recovery system |
| US8176926B2 (en) * | 2008-03-26 | 2012-05-15 | Meiko Maschinenbau Gmbh & Co. Kg | Batch dishwasher with waste water heat recovery |
| WO2012061945A1 (en) * | 2010-11-10 | 2012-05-18 | Ambercore Software Inc. | System and method for object searching using spatial data |
| FR2987670A1 (en) * | 2012-03-05 | 2013-09-06 | Energy Harvesting Tech | DEVICE FOR THE RECOVERY OF THERMAL ENERGY FROM A FLOW OF WASTE WATER |
| WO2013131930A3 (en) * | 2012-03-05 | 2014-12-04 | Energy Harvesting Tech | Device for recovering thermal energy from a flow of waste water |
| US10633838B2 (en) | 2013-03-05 | 2020-04-28 | Energy Harvesting Tech | Device for recovering thermal energy from a flow of waste water |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |