WO2018019615A1

WO2018019615A1 - A device to provide in-line purified hot water

Info

Publication number: WO2018019615A1
Application number: PCT/EP2017/067835
Authority: WO
Inventors: Ganesh Deshpande; Debasis Mukherjee; Ajit Ganesh RAWOOL; Skand Saksena
Original assignee: Unilever N.V.; Unilever Plc; Conopco, Inc., D/B/A Unilever
Priority date: 2016-07-28
Filing date: 2017-07-14
Publication date: 2018-02-01
Also published as: CN109561790A; CN207552093U

Abstract

The invention relates to a device (100) to provide in-line purified hot water. The device comprises a water purifying system (101), a pressurizable tank (102), an instant heater (103) and a pump (104) to pump water through the water purifying system into the pressurizable tank. The device further comprises a high pressure switch (105) positioned upstream the pressurizable tank. The high pressure switch controls the pumping of the water through the water purifying system into the pressurizable tank in such a way that the pump starts pumping water through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1034 hPa and that the pump continues to pump water through the water purifying system into the pressurizable tank till the water pressure in the pressurizable tank reaches 4136 hPa.

Description

A device to provide in-line purified hot water Field of the invention

The present invention relates to a device to provide in-line purified hot water and more particularly to a device to provide in-line purified hot water in a predetermined temperature range.

The invention further relates to a method of providing hot purified water by such device.

Background of the invention

Water purifying systems as well as hot water dispensers are known in the art.

Water purifying systems comprise for example gravity fed devices or devices using reverse osmosis, ultra-filtration or UV radiation. Basically such water purifying systems are based on a mechanism to remove suspended and dissolved impurities and/or to make the water microbiologically safe.

Hot water dispenser are popular to provide water for drinking purposes. Such systems are in particular popular in cold countries for example for making beverages like tea or coffee. Most types of hot water dispenser have a small thermally-insulated tank provided with a heater keeping the water in the tank at a temperature near the boiling temperature of water. When the hot water button of the batch heater is pressed, cool water flows into the tank and displaces the near-boiling water which flows out of the spout. On releasing the hot water button the valve closes and hot water stops flowing. The cool water is then heated to a temperature near the boiling temperature of water.

Nowadays, instant heaters are gaining popularity as such heaters are more user friendly and more energy efficient. Instant heaters provide hot water only as needed and do not produce standby energy losses associated with storage water heaters. The temperature of water dispensed by an instant heater depends on the time the water spends in the instant heater which in turn depends on the flow rate of the water.

To provide purified hot water there is a need to combine a water purification system with a heater. However, combining a water purification system with an instant heater is challenging as the output flow rate of a water purification system is not constant while an instant heater requires a constant flow rate. The output flow rate of a water purifying system is in most cases not constant and depends for example upon the input water pressure, the water quality, the technique used to purify water, the fouling of the medium of the purification system etc.

For instant heaters providing water near boiling temperature (for example water at a temperature between 75 and 95 °C, for example at a temperature of 80 °C or 90 °C) a non-constant flow rate may lead to the following unsafe conditions for the consumer: if the flow rate is lower than the desired flow rate, the temperature can reach the boiling temperature of water causing the generation of steam. On the other hand if the flow rate is higher than the desired flow rate, the temperature of the dispensed water will not reach the desired temperature, which is not desirable for the consumer. Also, as the desired output water temperature is in the range 75-95°C it is essential to maintain this temperature range and prevent over heating of the water to boiling point which is unsafe or having it at low temperatures which is not really beneficial and desirable.

WO 2016/066382 (Unilever) discloses a water purifier comprising, a pump; a membrane module where the membrane is spiral wound membrane including reverse osmosis, nanofilter, ultrafilter and microfilter membranes; a first valve to control the water flow into the membrane module; and a permeate line for purified water and a reject line for discarded water; wherein the reject line comprises a valve; and wherein the water purifier comprises a closed chamber and a second valve in sequence downstream the membrane module in the permeate line and wherein the reject line is downstream of the membrane module. The patent application does not deal with the problem of having an inline water heater, maintaining a temperature range and prevention of over heating of the device.

Therefore there is a need for a device which dispenses purified hot water in the temperature range of about 75 to 95°C and such that the desired temperature range is maintained. Summary of the invention

It is an object of the present invention to provide a device to provide in-line purified hot water that allows to dispense hot water independent of the flow rate of the water through the water purifying system. It is another object of the present invention to provide a device to provide in-line purified hot water that dispense water at the desired temperature without causing unsafe conditions for the consumer.

It is a further object of the present invention to provide a method of dispensing hot purified water from a device comprising a water purifying system and an instant heater. According to a first aspect of the present invention a device to provide in-line purified hot water is provided. The device comprises a water purifying system; a pressunzable tank in fluid communication with the outlet of the water purifying system, - an instant heater in fluid communication with the outlet of the pressurizable tank; a pump to pump water through the water purifying system into the pressurizable tank.

The device according to the present invention further comprises a high pressure switch positioned upstream the pressurizable tank whereby the high pressure switch controls the pumping of the water through the water purifying system into the pressurizable tank in such a way that the pump starts pumping water through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1034 hPa and that the pump continues to pump water through the water purifying system into the pressurizable tank till the water pressure in the pressurizable tank reaches 4136 hPa. Second aspect of the present invention provides a method of dispensing hot purified water from a device of the first aspect, the method comprising the step of pumping water through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1034 hPa and continuing the pumping of water through the water purifying system into the pressurizable tank until the water pressure in the pressurizable tank reaches 4136 hPa.

Third aspect of the present invention provides use of a device of the present invention for providing water in a constant temperature range.

Water purifying system Water purification is the process of removing particles or substances from (contaminated) water as for example undesirable chemical or biological contaminants or suspended solids.

The goal of a water purifying system is to produce water fit for a specific purpose. Most commonly water is purified to provide drinking water (water for human consumption) although water purification can also be used for a variety of other purposes such as purification to fulfil the requirements of medical, pharmacological, chemical and industrial process.

Water purifying systems may be based on a number of different processes such as filtration; activated carbon filtration; reverse osmosis; sedimentation; distillation; aeration; ion exchanging; chemical processes such as chlorination or flocculation, radiation as for example ultraviolet (UV) radiation. Water purifying systems based on filtration may for example comprise ultrafiltration, microfiltration or nanofiltration (depending on the pore size of the filtration medium).

The water purifying system of the device of the present invention has an inlet and an outlet. The inlet receives water from a water supply system, such as for example a municipal water supply system.

The outlet is preferably in fluid communication with the pressurizable tank, more particularly with the inlet of the pressurizable tank. Pressurizable tank

A pressurizable tank or pressurized vessel is a container designed to hold a liquid (water) at a predefined pressure, for example a pressure different from ambient pressure.

The pressurizable tank of a device according to the present invention is for example made of a metal or metal alloy as for example steel. Alternatively the pressurizable tank can be made of a polymer material, such as polyethylene terephthalate (PET) or of a composite material, for example a reinforced polymer material.

The volume of the pressurizable tank is preferably ranging between 1 and 10 litre, for example between 2 and 8 litre. The pressurizable tank of the device according to the present invention has an inlet and an outlet. The inlet of the pressurizable tank is preferably in fluid communication with the water purifying system. The outlet of the pressurizable tank is preferably in fluid communication with the instant heater, preferably with the inlet of the instant heater.

Instant heater An instant heater - also called tankless water heater, instantaneous, continuous flow, or inline heater - instantly heats water as it flows through the heater.

As instant heater any type of instant heater known in the art can be considered.

The heating element or heat exchanger of the instant heater comprises for example a tube, coil or plate, for example a metal tube, a metal coil or metal plate or a quartz tube, a quartz coil or a quartz plate. The heating element may also comprise a coated tube, a coated coil or a coated plate for example a tube, coil or plate coated with a metal oxide coating, for example a quartz tube coated with a metal oxide coating.

In case the heating element comprises a metal or metal alloy heating element, copper or a copper alloy is preferred because of its high thermal conductivity. The instant heater of the device according to the present invention can be an electric instant heater of a gas fired instant heater. Preferably, the instant heater is heating the water till a temperature ranging between 75 and 95 °C is reached, for example till a temperature of 80 °C, 85 °C or 90 °C is reached.

The instant heater of a device according to the present invention has an inlet and an outlet. The inlet of the instant heater is in fluid communication with the pressurizable tank. The outlet of the instant heater dispenses the hot purified water.

Pump

As pump any type of pump that is able to pump water through the water purifying system into the pressurizable tank can be considered.

The pump receives water from an inlet and sends water through the water purifying system into the pressurizable tank.

High pressure switch

A pressure switch is a device designed to monitor a process pressure and provide an output, for example opening or closing an electrical contact, when a predetermined pressure or a predetermined range of pressures is reached. As pressure switch any pressure switch known in the art can be considered. Examples comprise electromechanical switches. Most commonly used pressure switches use a diaphragm or bellow as sensing element. The movement of such sensing element is used to actuate one or more switch contacts.

The high pressure switch of the device according to the present invention is positioned upstream the pressurizable tank, more preferably upstream the pressurizable tank and downstream the water purifying system.

The high pressure switch controls the pumping of the water (for example supplied by a water supply system) through the water purifying system into the pressurizable tank in such a way that the pump starts pumping water through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1034 hPa and that the pump continues to pump water through the water purifying system into the pressurizable tank till the water pressure in the pressurizable tank reaches 4136 hPa. In a more preferred embodiment the pressure switch controls the pumping of the water (for example supplied by a water supply system) through the water purifying system into the pressurizable tank in such a way that the pump starts pumping water through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1723 hPa and that the pump continues to pump water through the water purifying system into the pressurizable tank till the water pressure in the pressurizable tank reaches 2557 hPa.

In preferred embodiments a device according to the present invention further comprises one or more additional components such as controllers or valves. Examples of such additional components comprise one or more flow regulators, one or more solenoid valves, one or more pressure switches as for example one or more low pressure switches or a combinations thereof.

Preferred additional components are described below in more detail. Flow regulator A device according to the present invention may comprise one or more flow regulators. Preferably, a flow regulator is installed at the inlet of the instant heater, i.e. upstream the inlet of the instant heater, more particularly upstream the instant heater and downstream the water purifying system.

A flow regulator or flow restrictor is a device to restrict the flow of a fluid, for example water.

Any type of flow regulator known in the art can be considered. Low pressure switch

Preferably, a device according to the present invention further comprises a low pressure switch. Such low pressure switch is preferably positioned upstream the water purifying system.

Preferably, such low pressure switch controls if there is a supply of water. The low pressure switch preferably shuts down the pump when the water pressure of the flow of water to be introduced in the water purifying system is lower than 344 hPa. The water to be introduced to the water purifying system generally corresponds with the water supplied from a water supply system as for example the municipal water supply system. A water pressure lower than 344 hPa generally corresponds with no supply of water.

Solenoid valve

Preferably, a device according to the present invention preferably comprises one or more solenoid valves. A device according to the present invention comprises for example a solenoid valves to control the flow of water flowing from the pressurizable tank to the instant heater. Preferably, the solenoid valve is positioned between the pressurizable tank and the instant heater, i.e. downstream the pressurizable tank and upstream the instant heater.

A solenoid valve is an electromechanically operated valve, for example used to control the flow of a liquid. Generally, a solenoid valve is operated by opening and closing an orifice permitting or preventing a flow flowing through the valve. In a closed position, the flow is prevented to flow through the valve. The orifice is opened or closed through the use of a plunger that is raised or lowered by energizing the coil of the solenoid valve. When the coil is energized, a magnetic field is produced allowing the flow through the valve. Preferably, the coil is energized when the consumer presses the hot water dispense button. This means that by pressing the hot water dispense button, water is allowed to flow from the pressurizable tank to the instant heater and subsequently to the faucet to dispense hot purified water to the consumer.

According to a second aspect of the present invention a method to dispense hot purified water is provided. The hot purified water is preferably dispensed from a device as described above. The device preferably comprises a water purifying system, a pressurizable tank, an instant heater, a pump and a high pressure switch. Possibly, the device further comprises one or more flow regulators, one or more solenoid valves and/or one or more pressure switches such as one or more low pressure switches. The method comprises the step of pumping water through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1034 hPa and continuing the pumping of water through the water purifying system into the pressurizable tank until the water pressure in the pressurizable tank reaches 4136 hPa.

In a preferred method the water is pumped through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1723 hPa and the pumping of the water through the water purifying system into the pressurizable tank until the water pressure in the pressurizable tank reaches 2557 hPa. A preferred method of dispensing hot purified water according to the present invention comprises the step of allowing water present in the pressurizable tank to flow to the instant heater to heat the water in the instant heater to a predetermined temperature or a predetermined range of temperatures. The predetermined temperature is for example a temperature ranging between 75 and 95 °C; the predetermined range of temperatures corresponds for example with a range of temperatures from 75 °C and 95 °C.

The flow of water from the pressurizable tank to the instant heater is for example controlled by a solenoid valve. The coil of the solenoid valve is energized when the consumer presses the hot water button. By doing so the valve is opened and water is allowed to flow from the pressurizable tank to the instant heater. Brief Description of the Drawings:

The invention will now be described into more detail with reference to the accompanying drawings whereby

Figure 1 shows an illustration of a device to provide in-line purified water according to the present invention. Detailed description of the invention

The present invention will be described with respect to particular embodiments and with reference to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and non-limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes. The dimensions and the relative dimensions do not correspond to actual reductions to practice of the invention.

The present invention solves the problem of providing a device which dispenses purified hot water in the temperature range of about 75 to 95°C and such that the desired temperature range is maintained. The present inventors have surprisingly found that the problem of dispensing hot water in the temperature range 75-95°C in an inline water purifier can be achieved by providing a pressurizable tank and a high pressure switch positioned upstream the pressurizable tank whereby the high pressure switch controls the pumping of the water through the water purifying system into the pressurizable tank in such a way that the pump starts pumping water through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1034 hPa and that the pump continues to pump water through the water purifying system into the pressurizable tank till the water pressure in the pressurizable tank reaches 4136 hPa.

The present invention provides a device to provide in-line purified hot water, the device comprising a water purifying system , a pressurizable tank in fluid communication with the outlet of the water purifying system ; an instant heater in fluid communication with the outlet of the pressurizable tank

a pump to pump water through the water purifying system into the pressurizable tank ; characterized in that the device further comprises a high pressure switch positioned upstream the pressurizable tank whereby the high pressure switch controls the pumping of the water through the water purifying system into the pressurizable tank in such a way that the pump starts pumping water through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1034 hPa and that the pump continues to pump water through the water purifying system into the pressurizable tank till the water pressure in the pressurizable tank reaches 4136 hPa.

It is preferable that the device of the present invention further comprises a flow regulator positioned downstream the pressurised tank and upstream the instant heater. It is preferred the instant heater comprises a tube, coil or plate as heating element or heat exchanger.

It is preferable that the water purifying system comprises a filtration based system such as a ultrafiltration, microfiltration or nanofiltration system or an activated carbon filtration system; a reverse osmosis based system; a sedimentation based system; a distillation based system; an aeration based system; an ion exchanging based system; a system based on chemical processes such as chlorination or flocculation or a radiation based system.

It is preferred that the flow of water from the pressurizable tank to the instant heater is controlled by a solenoid valve. It is preferable that the device of the present invention further comprises a low pressure switch , the low pressure switch being positioned upstream the water purifying system whereby the low pressure switch stops pumping of water when the water pressure of the flow of water to be introduced to the water purifying system is lower than 344 hPa.

The present invention also provides a method of dispensing hot purified water from a device of the present invention, the method comprising steps of pumping water through the water purifying system into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1034 hPa and continuing the pumping of water through the water purifying system into the pressurizable tank until the water pressure in the pressurizable tank reaches 4136 hPa. It is preferred that the method further comprises steps of allowing water present in the pressurizable tank to flow from the pressurizable tank to the instant heater to heat the water to a predetermined temperature or a predetermined range of temperatures. It is preferable that the flow of water from the pressunzable tank to the instant heater is controlled by a solenoid valve.

The present invention also provides use of a device of the present invention for providing water in a constant temperature range. It is preferred that the temperature range varies around 75 to 95 °C.

Figure 1 shows a schematic illustration of a device 100 to provide in-line purified water according to the present invention.

The device 100 comprises a water purifying system 101 , a pressurizable tank 102, an instant heater 103 and a pump 104. The device 100 further comprises a high pressure switch 105.

The water purifying system 101 is in fluid communication with the outlet of the pressurizable tank 102; the instant heater 103 is in fluid communication with the outlet of the pressurize tank 102.

The high pressure switch 105 is positioned upstream the pressurizable tank 102. The high pressure switch 105 controls the pumping of the water by pump 104 through the water purifying system 101 into the pressurizable tank 102 in such a way that the pump 104 starts pumping water through the water purifying system 101 into the pressurizable tank 102 when the water pressure in the pressurizable tank 102 is lower than 1034 hPa and that the pump 104 continues to pump water though the water purifying system 101 into the pressurizable tank 102 till the water pressure in the pressurizable tank 102 reaches 4136 hPa.

A flow of water is introduced form a water supply 106, for example the municipal water supply, to the water purifying system 101 through pump 104. Subsequently, the water is pumped from the water purifying system 101 to the pressurizable tank 102. The water purifying system 101 may comprises one or more filtration units, for example one, two, three, four or five filtration units. The water purifying system 101 comprises for example one or more sediment filtration units and/or one or more carbon filtration units and/or one or more reverse osmosis units and/or one or more ultra-, micro- or nanofiltration units. A sediment filtration unit comprises for example a filter made of polymer fibers or melt blown polymer filaments, for example polypropylene fibers or filaments. A carbon filtration unit comprises for example a carbon block or loose carbon bed fitted in a cartridge. The ultra-, micro- or nanofiltration units comprises preferably the final stage of filtration.

The water purifying system 101 shown in figure 1 comprises two filtration units 101 a, 101 b.

The pressurizable tank 102 comprises for example a polymer tank having a volume ranging between 1 and 8 litre, for example 5 I.

The pump 104 comprises for example a reciprocating pump, a rotary vein pump, a diaphragm pump or an external or internal gear pump. Preferably, the device 100 is further equipped with a low pressure switch 107 and/or with a solenoid valve 108 and/or with a flow regulator 109.

A low pressure switch 107 can be positioned upstream the water purifying system 101 or after 101 a and preferably detects if there is supply of water to the device 100.

If there is no supply of water, the pump 104 preferably shuts down. If the low pressure switch 107 senses a water pressure for example lower than 344 hPa, the low pressure switch shuts down pump 104.

A solenoid valve 108 is preferably installed downstream the pressurizable tank 102 and upstream the instant heater 103 and preferably controls the flow of water from the pressurizable tank 102 to the instant heater 103. A flow regulator 109 is preferably installed upstream the inlet of the instant heater 103 and downstream the water purifying system 101.

The water is dispensed through faucet 1 10.

The device 100 may further be used to provide cold water. To provide cold water the purified water from the water purifying system 101 is supplied to faucet 1 10 through conduit 1 1 1. The flow of water from the water purifying system 101 to the faucet 1 10 can for example be controlled by a solenoid valve 1 12. For a person skilled in the art it is clear that the water provided through faucet 1 10 can be a mixture of cold water supplied through conduit 1 1 1 and hot water supplied through the instant heater 103 through conduit 1 13.

Claims

1 A device (100) to provide in-line purified hot water, the device (100) comprising a water purifying system (101 ), a pressurizable tank (102) in fluid communication with the outlet of the water purifying system (101 ); an instant heater (103) in fluid communication with the outlet of the pressurizable tank (102); a pump (104) to pump water through the water purifying system (101 ) into the pressurizable tank (102); characterized in that the device (100) further comprises a high pressure switch (105) positioned upstream the pressurizable tank (102) whereby the high pressure switch (105) controls the pumping of the water through the water purifying system

(101 ) into the pressurizable tank (102) in such a way that the pump (104) starts pumping water through the water purifying system (101 ) into the pressurizable tank

(102) when the water pressure in the pressurizable tank (102) is lower than 1034 hPa and that the pump (104) continues to pump water through the water purifying system (101 ) into the pressurizable tank (102) till the water pressure in the pressurizable tank (102) reaches 4136 hPa.

2 A device (100) according to claim 1 , whereby the device (100) further comprises a flow regulator (109) positioned downstream the pressurised tank (102) and upstream the instant heater (103).

3 A device (100) according to claim 1 or claim 2, whereby the instant heater (103) comprises a tube, coil or plate as heating element or heat exchanger.

4 A device (100) according to any one of the preceding claims, whereby the water purifying system (101 ) comprises a filtration based system such as a ultrafiltration, microfiltration or nanofiltration system or an activated carbon filtration system; a reverse osmosis based system; a sedimentation based system; a distillation based system; an aeration based system; an ion exchanging based system; a system based on chemical processes such as chlorination or flocculation or a radiation based system. A device (100) according to any one of the preceding claims, whereby the flow of water from the pressurizable tank (102) to the instant heater (103) is controlled by a solenoid valve (108). A device (100) according to any one of the preceding claims, whereby the device (100) further comprises a low pressure switch (107), the low pressure switch (107) being positioned upstream the water purifying system (101 ) whereby the low pressure switch (107) stops pumping of water when the water pressure of the flow of water to be introduced to the water purifying system (101 ) is lower than 344 hPa. A method of dispensing hot purified water from a device (100) according to any one of claims 1 to 6, the method comprising the step of pumping water through the water purifying system (101 ) into the pressurizable tank when the water pressure in the pressurizable tank is lower than 1034 hPa and continuing the pumping of water through the water purifying system into the pressurizable tank (101 ) until the water pressure in the pressurizable tank (101 ) reaches 4136 hPa. A method of dispensing hot purified water according to claim 7, the method further comprising the step of allowing water present in the pressurizable tank (102) to flow from the pressurizable tank (102) to the instant heater (103) to heat the water to a predetermined temperature or a predetermined range of temperatures. A method of dispensing hot purified water according to claim 8, whereby the flow of water from the pressurizable tank (102) to the instant heater (103) is controlled by a solenoid valve (108). Use of a device according to claims 1 to 6 for providing water in a constant temperature range.