WO2012141587A2

WO2012141587A2 - System and method for heating process medium for use in a textile laundry

Info

Publication number: WO2012141587A2
Application number: PCT/NL2012/050246
Authority: WO
Inventors: Johannes Van Oorspronk; Jakob Hendrik Reinders; Henk Klatter; Alain Joseph Andre Bostoen
Original assignee: Christeyns N.V.; Ems Rotor B.V.
Priority date: 2011-04-14
Filing date: 2012-04-13
Publication date: 2012-10-18
Also published as: WO2012141587A3; NL2006599C2

Abstract

The present invention relates to a method and system for heating process medium for use in a textile treatment module of a textile laundry, comprising a first heating device coupled to a feed for process medium and adapted to preheat the process medium, a second heating device coupled to the first heating device and adapted to further heat the preheated process medium, a mixing device coupled to the first and the second heating device, and adapted to mix process medium preheated by the first heating device and process medium further heated by the second heating device, and discharging the mixed process medium to the textile treatment module.

Description

System and method for heating process medium for use in a textile laundry

The invention relates to a system and method for heating process medium for use in a textile laundry.

Industrial textile cleaning is a service industry which responds to the need to be able to reuse textile in an attractive and hygienic manner. In industrial laundries diverse types of textile, usually formed by clothing, bed linen and towels and so on, are here washed in wet manner, wherein use is made of washing water which is provided with detergents and which is brought at increased temperature into intensive contact with the textile for cleaning.

The alkaline washing water is here generally first heated, after which the washing water can actually be applied. The washing water is generally discharged after use. Discharge generally takes place via the sewage system or the surface water, usually after sand, textile fibres and other components have been separated by filtering from the waste water to be discharged.

Different options are known for heating the washing water. A method known for many years is to heat the water by means of steam generated in a steam boiler. This method is however environmentally unfriendly, among other reasons because of the low efficiency thereof. The Netherlands patent NL 1028933 proposes making use of the heat of water from a previous wash. Although this achieves a considerable improvement from an environmental viewpoint, the amount of heat which can be supplied to already used water is generally insufficient to also heat a fresh quantity of water to a desired temperature level.

The invention therefore has for its object to provide a further improved system for heating process medium, particularly water, for use in a textile laundry, or to provide usable alternative to the existing systems and methods.

The invention provides for this purpose a system for heating process medium for use in a textile treatment module of a textile laundry, comprising a first heating device coupled to a feed for process medium and adapted to preheat the process medium, a second heating device coupled to the first heating device and adapted to further heat at least a part of the preheated process medium, which second heating device comprises at least one solar collector for further heating the preheated process medium; and at least one connecting conduit for guiding the process medium heated by the first heating device and second heating device to the textile treatment module. As described in the prior art, the first heating device can be based on the use of residual heat of a process medium used during a textile treatment step performed earlier. The process medium can be brought into physical contact here with the textile for treating (direct application). The process medium will generally consist here of water (or steam), optionally provided with additives. It is also possible to envisage the process medium being applied for the purpose of heating a textile treatment module such as a wringer or drier (indirect application). In this indirect application use can be made of water, but also of other liquids such as oil or glycol. It may be the case that the previous wash (or other textile treatment process step) took place at a higher temperature than a subsequent wash, or this latter takes place with a smaller quantity of process medium than the previous wash. In this case the amount of heat produced by the already used process medium may be sufficient to heat the process medium for the purpose of a subsequent wash. The process medium preheated by the first heating device can be further heated until a desired washing temperature is reached by applying a second heating device based on solar energy. The use of solar energy is environmentally-friendly, relatively inexpensive and durable, and moreover results in an efficient and sufficient heating of the process medium to be used. It is not necessary here for the whole quantity of process medium coming from the first heating device to be guided through the second heating device. At least a part can also be guided not via the second heating device but directly from the first heating device into the textile treatment module. Use can be made of a bypass conduit for the purpose of bypassing the second heating device. Depending on the situational factors, such as the starting temperature of the process medium for heating, the capacity of the first heating device, the capacity of the second heating device, the heat loss in applied transport conduits, the desired flow rate and the desired (final) temperature of the process medium, the ratio of the flow rate through the bypass conduit and the flow rate through the second heating device can be regulated by applying a control element. It is possible here to envisage that the whole fraction of process medium coming from the first heating device is guided through the bypass conduit and that the second heating device is not utilized for further heating. It is also possible to envisage a reverse situation, in which the bypass conduit is closed and the whole fraction of the process medium coming from the first heating device is guided through the second heating device. A part of the process medium coming from the first heating device will generally be guided in practice through the bypass conduit, and a remaining part will be guided through the second heating device.

Before the heated process medium is guided into the textile treatment module and brought into contact with the textile for cleaning, it is generally advantageous to mix the process medium coming from the bypass conduit and the process medium coming from the second heating device in a mixing device before feeding the process medium to the textile treatment module, this in order to enable the washing process to proceed in the most controlled manner possible. The mixing device can then be set here to carry to the textile treatment module only the process medium heated in the first heating device. It is however found to be desirable in practice to wash with process medium having a higher temperature than the process medium preheated by the first heating device. Provided - as stated - for this reason is the second heating device, which heats to a higher temperature the process medium preheated by the first heating device.

It may however also be the case that the second heating device makes use of an alternative, non-controllable ("green") energy source other than solar energy, whereby the process medium becomes hotter than the temperature required for washing. In this case the mixing device can feed a chosen mixing ratio of process medium heated by the first and the second heating devices to the textile treatment module such that precisely the desired temperature is obtained. Process medium heated to too high a temperature is in this way saved for a further wash. In the case of industrial services a large number of successive washes generally take place so that storing heated process medium is unquestionably advantageous.

In an embodiment the first heating device comprises a heat exchanger for preheating process medium with residual heat from process medium discharged from the first textile treatment module. The residual heat of process medium from a preceding wash is in this way reused efficiently. Diverse embodiments of heat exchangers are known, although it is recommended according to the present invention to make use of a heat exchanger with a rotatable hollow tube provided with serially connected hollow discs and placed in a reservoir for receiving process medium discharged from the first textile treatment module, and adapted for throughfeed of the process medium to be used for preheating thereof. Such a heat exchanger is described at length in the Netherlands patent NL 1028933.

The second heating device more preferably comprises at least one vacuum tube solar collector. Such a heating device comprises one or more double-walled, usually glass tubes between which and/or in which the vacuum is formed. Heat is hereby retained particularly well. A heat-absorbing coating will generally be applied to at least a part of the inner wall of the tube. Situated in the tube is an axially extending, heat-absorbing pipe or rod, preferably manufactured from a heat-conducting material such as copper. This pipe is also referred to as heat pipe. Because the pipe absorbs and conducts heat particularly effectively, an outer end of the pipe can be used for transfer of heat to generally circulating processing medium flowing past. This process medium can thereby reach very high temperatures, which are even too high for the washing process, whereby it can be mixed to a temperature suitable for the washing process by being mixed with process medium from the first heating device. The process medium guided along the vacuum tube solar collector(s) can be process medium for feeding to the textile treatment module (direct heat transfer), but can also be a secondary process medium such as (secondary) process water or oil, via which the process medium for feeding to the textile treatment module is heated (indirect heat transfer). The second heating device can itself comprise a reservoir and be adapted to circulate the process medium from the reservoir through the vacuum tube solar collector. The process medium from this reservoir, optionally after being mixed with process medium coming from the first heating device, can then be added to the textile treatment module.

In a further embodiment the system comprises a supply device for additives for the purpose of enriching the process medium for feeding to the textile treatment module. The addition of additives can take place at diverse locations, such as upstream of or in the first heating device, upstream of or in the second heating device, in the bypass conduit or in the mixing device The bypass conduit and/or the mixing device will generally be preferred so as not to foul the heating devices with additives. Examples of additives are soap, fabric softeners or other washing products. The second heating device can then be connected via a boiler to the mixing device. This can be used when the residual heat and/or solar heat are insufficient to heat the process medium. The boiler can be adapted here to circulate process medium via a process medium heater, particularly a hot water heater, such as a geyser.

The system according to the present invention can also comprise a filter device for filtering dirt, textile or soap contaminants from process medium discharged from the textile treatment module before feeding the discharged process medium to the heat exchanger. In this way the heat exchanger is not fouled, and no harmful substances enter the environment after the exchange of heat. The system can then be adapted without problem to drain process medium discharged from the textile treatment module following the heat exchange. In an alternative embodiment the system is adapted to feed the process medium discharged from the textile treatment module to the first heating device following the heat exchange.

The invention also relates to a method for heating process medium for use in a textile treatment module of a textile laundry, particularly by applying a system according to the invention, comprising of: preheating the process medium with a first heating device; further heating at least a part of the preheated process medium by means of solar energy in a second heating device; and discharging the mixed process medium to the textile treatment module. In an advantageous embodiment a part of the process medium preheated by the first heating device is guided through the second heating device, and wherein the process medium heated only by the first heating device is mixed with the process medium heated by both the first heating device and the second heating device. In a further embodiment process medium is preheated in the first heating device by means of residual heat which is entrained by (already used) process medium discharged from a textile treatment module. A vacuum tube solar collector is preferably applied in the second heating device to further heat in relatively efficient and effective manner process medium preheated in the first heating device. As soon as the process medium has been heated by the first heating device, and optionally the second heating device, it is generally advantageous to hold the process medium at temperature by circulating the process medium via a process medium heater, such as a geyser. Further embodiments and advantages of the method according to the invention have already been described at length in the foregoing. The invention will be elucidated with reference to the following non-limitative figure 1, which shows a schematic overview of a system according to the present invention. Figure 1 shows a system 1 for heating water for use in a washing chamber 2 of a textile laundry, comprising a first heating device 3 coupled to a feed 4 for water and adapted to preheat the water, as well as a second heating device 5 coupled to the first heating device 3 and adapted to further heat the preheated water. The system comprises a first mixing device 6 coupled to first and second heating devices 3, 5 and adapted to mix water preheated by the first heating device 3 with water further heated by the second heating device 5, and discharging the mixed water to washing chamber 2. The first heating device comprises a heat exchanger 7 with a rotatable hollow tube 8 placed in a reservoir 9 for receiving water discharged from the first washing chamber 2 and carrying with it residual heat. In first washing chamber 2 the water freshly supplied via feed 4 is guided through hollow tube 8 and in this way heated by the already used water. The water heated in heat exchanger 7 can optionally be stored in a reservoir 18 and, if desired, be enriched with one or more additives such as detergents in a second mixing device 14. A part of the water coming from second mixing device 14 can be supplied to first mixing device 6. A remaining part will be guided to a solar boiler 10 for further heating of the water. The water is guided for this purpose out of solar boiler 10 through a heat exchanger 15 and fed back again to solar boiler 10. Heat exchanger 15 also forms part of a secondary circuit 16 for heating the water in heat exchanger 15. This secondary circuit 16 together with solar boiler 10 is deemed to be the second heating device 5. The secondary circuit comprises a plurality of vacuum tube solar collectors 9 for heating a secondary process medium, such as water or glycol, to be guided through heat exchanger 15.

The water coming from second heating device 5 can be stored in a boiler 11 and optionally be further heated to a desired temperature by applying a hot water heater 12 such as a geyser.

The system is further provided with a filter device 13 for filtering dirt, textile or soap contaminants from the water discharged from washing chamber 2 before the discharged water is fed to heat exchanger 7. The water heated to a desired temperature can then be fed to a washing chamber 2, such as a washing tunnel or washer extractor (washing machine), and/or to other textile treatment components 17 such as a drier. The heated water can optionally be converted in a steam boiler 18 to steam for supplying to a wringer 19.

It will be apparent that the invention is not limited to the exemplary embodiments shown and described here, but that within the scope of the appended claims numerous variants are possible which will be self-evident to the skilled person in this field.

Claims

1. System for heating process medium, in particular water, for use in a textile laundry, comprising:

- a first heating device coupled to a feed for a process medium and adapted to preheat the process medium;

a second heating device coupled to the first heating device and adapted to further heat at least a part of the preheated process medium, which second heating device comprises at least one solar collector for further heating the preheated process medium; and

at least one connecting conduit for guiding the process medium heated by the first heating device and second heating device to at least one textile treatment module adapted to use the heated process medium.

2. System as claimed in claim 1, wherein the system comprises at least one bypass conduit for guiding at least a part of the process medium preheated by the first heating device directly to the textile treatment module.

3. System as claimed in claim 2, wherein the system comprises a mixing device coupled to the bypass conduit and the second heating device, which mixing device is adapted to mix together only process medium preheated by the first heating device and process medium heated by both the first heating device and the second heating device, wherein the mixing device is further coupled to the connecting conduit.

4. System as claimed in any of the foregoing claims, wherein the first heating device comprises a heat exchanger for preheating process medium with residual heat from process medium discharged from the first textile treatment module.

5. System as claimed in claim 4, wherein the heat exchanger comprises a rotatable hollow tube placed in a reservoir for receiving process medium discharged from a textile treatment module, and adapted for throughfeed of the process medium to be used for the purpose of preheating thereof

6. System as claimed in claim 4 or 5, comprising a filter device for filtering dirt, textile or soap contaminants from process medium discharged from the textile treatment module before feeding the discharged process medium to the heat exchanger.

7. System as claimed in any of the claims 4-6, adapted to drain process medium discharged from the textile treatment module following the heat exchange.

8. System as claimed in any of the claims 4-7, adapted to feed the process medium discharged from the textile treatment module to the first heating device following the heat exchange.

9. System as claimed in any of the foregoing claims, wherein the second heating device comprises at least one vacuum tube solar collector.

10. System as claimed in any of the foregoing claims, wherein the second heating device comprises a secondary circuit for a secondary process medium such as water or glycol, wherein the at least one solar collector is coupled to the secondary circuit for heating the secondary process medium, and wherein the second heating device further comprises at least one heat exchanger for transferring heat from heated secondary process medium to the process medium to be used in the textile laundry.

11. System as claimed in any of the foregoing claims, wherein the second heating device comprises a reservoir for storage of process medium heated in the second heating device.

12. System as claimed in any of the foregoing claims, wherein the system comprises a supply device for additives adapted to add additives to the process medium for guiding into the textile treatment module.

13. System as claimed in any of the foregoing claims, wherein the at least one textile treatment module is preferably formed by at least one of the following modules: a washing module, a wringer, a washer extractor, a drier and a finisher.

14. System as claimed in any of the foregoing claims, wherein the second heating device comprises a boiler.

15. System as claimed in claim 14, wherein the boiler is adapted to circulate process medium via a heater, such as a geyser.

16. Method for heating process medium for use in a textile treatment module of a textile laundry, particularly by applying a system as claimed in any of the claims 1-15, comprising of:

- preheating the process medium with a first heating device;

further heating at least a part of the preheated process medium by means of solar energy in a second heating device; and

discharging the mixed process medium to the textile treatment module.

17. Method as claimed in claim 16, wherein a part of the process medium preheated by the first heating device is guided through the second heating device, and wherein the process medium heated only by the first heating device is mixed with the process medium heated by both the first heating device and the second heating device.

18. Method as claimed in claim 16 or 17, comprising of:

- preheating process medium in the first heating device with residual heat from process medium discharged from a textile treatment module.

19. Method as claimed in any of the claims 16-18, comprising of:

- further heating the process medium preheated in the first heating device in the second heating device by means of at least one solar collector, in particular a vacuum tube solar collector.

20. Method as claimed in claim 19, comprising of:

- heating a secondary process medium by applying the at least one solar collector, and transferring heat in a heat exchanger from the heated secondary process medium to the process medium to be used in the textile laundry

21. Method as claimed in any of the claims 16-20, further comprising of: - circulating heated process medium via a heater, such as a geyser.