Field of the Invention

[001 ] The present invention relates to a liquid delivery system and in particular to hot water delivery system.

[002] The invention has been developed primarily for use in domestic hot water delivery system and will be described hereinafter with reference to this application. However, it will be appreciated that the invention is not limited to this particular field of use and can be used in various other capacities for supplying treated liquids/gases of all kinds.

Background of the Invention

[003] As shown in Fig. 1 existing hot water systems typically have a water heater tank 15 which is supplied with cold water that is heated to provide a continuous volume of hot water in the tank. Pipes lead from the hot water tank 15 to outlet faucets 17 along long lead lines 30. Water in the piping cools over time while the tank holds the hot water. When a faucet 17 is opened the entire volume of cold water in the lead lines between the heater tank 15 and the faucet 17 needs to be emptied before the hot water from the tank 15 finally arrives at the faucet 17. Therefore a substantial waste of water occurs each and every time hot water is required.

[004] Hot water delivery systems can be constructed to be types that aim to conserve water and energy. There are four main types of systems: a) hot water recirculation system b) crossover system c) water save system d) trace heating system

[005] The hot water recirculation system such as shown in Fig. 2 comprises a recirculation pipe extending from a furthest connection back to the hot water heater. A pump is required to effect the recirculation flow.

[006] The main requirement of this system is that a second pipe needs installing to connect the water heater to the furthest point in the system and include a pump to enable the return of water back to the water heater for reheating, which then keeps the water up to temperature. The pipes can have a volume of 5 or more litres of water in them. As all the water in the pipes needs to circulate and recirculate continually when in use or not, there is the expenditure of energy by the pump and excess energy by the water heater. When a tap is in use there can be substantial amount of cold not recirculated heated water that is dispensed and wasted until the recirculated heated water finally reaches the require faucet. Therefore multiples of the 5 or more litres of water can be wasted as expelled cold water before required heated water is expelled at the faucet.

[007] Therefore this system has the faults of: a) Pump runs continuously during set period of use. b) Only recirculates hot water to that furthest point, leaving cold dead legs to all other points. c) With added length of pipework, the heat loss from the pipework is now double, even with insulation on pipework. The water heater has to make up the loss with additional input of energy. d) Costly to install and not practical on existing installations. e) All hot water pipework has to be insulated to reduce energy loss.

[008] The crossover system such as shown in Fig 3 comprises a return pipe that also extends between the furthest point and the water heater. It also includes a pump to recirculate back to water heater. However, this system has the difference that it is similar to a hot water recirculation system but does not have any return pipework installed. Instead, there is a crossover valve and pump installed at the furthest point to allow the hot water to return to the water heater via the cold water pipework.

[009] However the system has the faults of: a) Same as the full circulation pipework installation, plus: part of the cold-water system can rise to 37°C temperature. b) Hot water is now being mixed with cold water before it returns to the water heater, which results in warm water in the draw off to toilets. This water could also end up as drinking water at taps/faucets. Cold water tap/faucet on the kitchen sink needs to be left running to get cold water. c) Hot water should not be used for cooking or drinking for the following reasons: i) Heated water may cause the plumbing system to release lead, nickel, etc. ii) Cold water is fresher, as hot water stays in the system for longer periods, and longer stagnation may cause higher bacterial levels. iii) Hot water is exposed to more pollution sources from tanks and heating system. iv) Level of micro-organisms is higher in hot water plumbing, and also corrosion rates in copper, brass, stainless steel and galvanised pipes is higher.

[0010] The water save system comprises the initial flow of cold water being saved from the system for re-use in toilets or rainwater use. However this system has the faults of needing to pipe the collected water somewhere: storage tanks, pressure vessels. It turns fresh drinking water into grey water/rainwater, and it still takes too long to come up to temperature. Also it has all of the same faults as the crossover system.

[0011] The trace heating system needs to be fitted with electrical heating trace tape to all the pipework on the hot water system. Therefore trace heating takes the form of an electrical heating element run in physical contact along the length of a pipe. However this system has the faults of being expensive to install and expensive to run. A long period of time is needed to heat the water in the pipework. It needs to be on 24 hrs per day to be effective.

[0012] It can be seen that known prior art liquid delivery systems have the problems of: a) Wastage of water b) Inefficient treating of liquid c) Wasted energy in treating volume of pipings or treating at all time d) Only providing benefits along one line e) Requiring excessive extra piping, heating tape or modifications to plumbing f) Not readily retrofittted

[0013] The present invention seeks to provide a Liquid Delivery System, which will overcome or substantially ameliorate at least one or more of the deficiencies of the prior art, or to at least provide an alternative. [0014] It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country. Summary of the Invention

[0015] According to a first aspect of the present invention, there is provided a liquid delivery system for supplying treated liquid at a delivery point comprising a liquid treatment system having a liquid treatment vessel for treating a liquid for delivery to a delivery port in a treated condition; a first pressure vessel selectably fluidly connected to the liquid treatment system; at least one second pressure vessel at or near the delivery port and selectably fluidly connected to the liquid treatment system. The system further has a first piping for circulating liquid to be treated between the first pressure vessel fluidly and the connected liquid treatment system; and a second piping for circulating treated liquid between the liquid treatment system and the connected second pressure vessel. At least one flow controller for selectively controlling the flow through the first piping and the second piping.

[0016] It can be seen that the invention of a liquid delivery system provides the benefit of providing a means of saving energy and water while still supplying treated material such as hot water faster than before.

[0017] According to a second aspect of the present invention, effecting selective operational steps of: a. A treatment step of circulating liquid to be treated through the first piping, in a first circuit, to enable treatment of liquid in the liquid treatment vessel of the liquid treatment system; or b. A distribution step of circulating liquid that has been treated through the second piping, in a second circuit, to the second pressure vessel to replace untreated liquid in the second piping with treated or partially treated liquid; or c. A diversion step of returning at least some untreated liquid and treated liquid from the distribution step, in a third circuit, from the second pressure vessel to the first pressure vessel to enable subsequent and progressive treatment of the liquid received by the first pressure vessel; or d. A standby mode where the liquid delivery system has filled with treated liquid and whereby the first pressure vessel is filled with a store of treated liquid and there is no flow of liquid; or e. A further distribution step of circulating liquid that has been treated and stored in the first pressure vessel through the first and second piping, in the second circuit, to the second pressure vessel.

[0018] The operational steps can further include a priming step where the liquid delivery system is filled with liquid. In this step the second pressure vessel has a set pressure substantially equal to incoming liquid pressure and the first pressure vessel has a set air pressure at least 50% lower than the set pressure in the second pressure vessel. In the priming step the control valve is on, and the pump is off and where liquid from an inlet source fills the delivery system until the air pressure in the first and second pressure vessel are substantially equal. When the delivery system is filled, there is no flow of liquid in the delivery system and the system is effectively in a standby static mode.

[0019] In a related aspect of the invention there is described a delivery system includes a first piping for circulating liquid to be treated between the first pressure vessel and the connected liquid treatment system; a second piping for circulating treated liquid between the liquid treatment system and the connected second pressure vessel; and a third piping interconnecting the first and second piping, wherein the third piping includes an intermediate valve means; a pump operable in one or more modes of operation; and a flow controller for controlling the intermediate valve means and pump; wherein a plurality of select piping circuits are provided by the fluid network for delivery of treated water in one of multiple modes of operation between the first and second pressure vessel to maintain treated liquid in a state for immediate use at an outlet.

[0020] The internal pressure of the second pressure vessel when empty can be greater than the internal pressure of the first pressure vessel when empty.

[0021 ] The internal pressure of the second pressure vessel when empty can be double the internal pressure of the first pressure vessel when empty.

[0022] The diversion step preferably includes returning liquid from the second pressure vessel to the first pressure vessel using the internal pressure differential between the first and second pressure vessels.

[0023] In a further related aspect, there is provided a liquid delivery system for supplying treated liquid at a delivery point comprising: a) A liquid treatment system having a liquid treatment vessel for treating a liquid for delivery to a delivery port in a treated condition; b) A first pressure vessel fluidly connected to the liquid treatment system by a first piping; c) At least one second pressure vessel fluidly connected to the liquid treatment system by a second piping, the second piping comprising one or more delivery ports for delivering treated liquid; d) A third piping selectively fluidly connecting the first pressure vessel and the second pressure vessel e) At least one flow controller for selectively controlling the flow through the first piping, the second piping, and the third piping.

[0024] The internal pressure of the second pressure vessel when empty, may be greater than the internal pressure of the first pressure vessel when empty the internal pressure of the second pressure vessel, when empty, may be double the internal pressure of the first pressure vessel when empty.

[0025] The flow controller may be configured to cause treated liquid to flow from the second pressure vessel to the first pressure vessel through the third piping using the internal pressure differential between the first and second pressure vessels.

[0026] It can be seen that the invention of a liquid delivery system provides the benefit of providing a pressure-controlled system that readily uses modified steps of flow to effect the required result.

[0027] Therefore, it can be seen that in one or more forms the invention achieves one or more advantages of: a) Instant hot water to selected tap/faucet positions with no water to run off to obtain hot water. b) No contamination of cold-water pipework and no recirculation needed. c) Can be fitted directly at tap/faucet connection under sink units, bathroom units and to new or existing systems. d) No pipework alterations are needed in buildings. It only needs a tee fitting to existing tap/faucet connection for small pressure vessel. e) Only a small alteration of pipework required at the hot water heating unit. f) One or more smaller pressure vessels can be fitted at most tap/faucet positions. g) Can be controlled by time clocks or remote push-button to switch on pump and controller. h) No stagnation of water in vessels, which would vastly reduce the risk of bacteria growth. i) Can be fitted to any type of sealed hot water system in the world, making all other systems obsolete.

[0028] Other aspects of the invention are also disclosed.

Brief Description of the Drawings

[0029] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Fig. 1 is diagrammatic view of a recirculation hot water system in accordance with the prior art;

Fig. 2 is diagrammatic view of a recirculation hot water system in accordance with the prior art;

Fig. 3 is a diagrammatic view of a crossover system in accordance with the prior art; Fig. 4 is a diagrammatic view of the apparatuses of liquid delivery system in the form of a hot water system ready for priming or filling in accordance with an embodiment of the invention;

Fig. 5 is a diagrammatic view of the system in a circulation mode of operation in a first circuit in accordance with an embodiment of the present invention;

Fig. 6 is a diagrammatic view of the system in a first pulse mode of operation in a second circuit in accordance with an embodiment of the present invention;

Fig. 7 is a diagrammatic view of the system in a returning liquid mode of operation in a third circuit in accordance with an embodiment of the present invention;

Fig. 8 is a diagrammatic view of the liquid delivery system in the form of a hot water system in a standby mode (i.e. no flow) with a store of treated/heated fluid/water in the first pressure vessel and piping in accordance with another embodiment of the invention including supporting pressure pumps to control differential pressures between Pi to P4;

Fig. 9 is a diagrammatic illustration of a further embodiment of the liquid delivery system in the form of a hot water system in a filling or priming mode;

Fig. 10 is a diagrammatic illustration of the liquid delivery system in figure 9 in the form of a hot water system in a standby operating mode with system primed with untreated/cold fluid/water but no liquid flow, i.e. static; Fig. 11 is a diagrammatic illustration of the liquid delivery system in figure 9 in the form of a hot water system in a circulating operating mode through a treatment device with pump running and control valve open heating fluid in circuit C1 ;

Fig. 12 is a diagrammatic illustration of the liquid delivery system in figure 9 in the form of a hot water system in a pulse operating mode with pump running and control valve shut thereby moving cold liquid from the first pressure vessel through a treatment device to the second pressure vessel and moving treated fluid from the circulation step from piping to the second pressure vessel;

Fig. 13 is a diagrammatic illustration of the liquid delivery system in figure 9 in the form of a hot water system in a returning operating mode with control valve open and pump not running thereby returning heated liquid from the second pressure vessel to the first pressure vessel;

Fig. 14 is a diagrammatic illustration of the liquid delivery system following figure 13 with control valve on and pump running to circulate any remaining untreated liquid about circuit C1 through the liquid treatment vessel;

Fig. 15 is a diagrammatic view of the system in a pulse mode of operation in a second circuit showing all liquid has been treated and flow of treated liquid within the delivery system from the first pressure vessel to the second pressure vessel in accordance with an embodiment of the present invention;

Fig. 16 is a diagrammatic view of the liquid delivery system in the form of a hot water system in a standby mode (i.e. no flow) with a treated/heated fluid/water in the second pressure vessel ready for use;

Fig. 17 is a diagrammatic flow diagram of a method of liquid delivery system for supplying treated liquid at a delivery point;

Fig. 18 is a diagrammatic view of an example of a solar hot water system modified to form liquid delivery system in the form of a hot water system in accordance with an embodiment of the invention;

Fig. 19 is an apparatus of liquid delivery system in the form of a hot water system in accordance with another embodiment of the invention including supporting pressure pumps and solar heating;

Fig. 20 is a diagrammatic view of an example of a sealed hot water system without solar or storage installed;

Fig. 21 is a diagrammatic view of purpose-made pressure vessel to fit back of sinks/bathrooms to suit all pipework water volumes in domestic installations; Fig. 22 is a diagrammatic view of pressure vessels at pulse pressure, system fully charged with pressure vessel 21 part empty and pressure vessel 22 part full;

Fig. 23 is a diagrammatic view of a pressure vessel at rest 21 , pressure vessel has the water/liquid returned to it, and the pressure vessel 22, has discharged its contents. System now at normal working pressure;

Fig. 24 is a diagrammatic system for pressure pulse system used on a dry fire sprinkler system to keep compressed air/nitrogen to optimal moisture content levels has an embodiment of liquid delivery’s system in accordance with the invention; Fig. 25 is a diagrammatic system for pressure pulse system used for compressed air lines to keep the air to optimal moisture content levels where it is critical for manufacturing progress has an embodiment of liquid deliver’s system in accordance with the invention;

Fig. 26 is a diagrammatic view of the system of the present invention installed on a cold mains water supply;

Fig. 27 is a diagrammatic view of the system of the present invention installed on an existing hot water system fitted with conventional hat water circulating piping; and Fig. 28 is a diagrammatic view of the system of the present invention installed in a reverse position.

Description of Preferred Embodiments

[0030] It should be noted in the following description that like or the same reference numerals in different embodiments denote the same or similar features.

[0031] Referring to the drawings and starting with Fig 4, there is shown a liquid delivery system for use in the operation of a pressure pulse hot water system in accordance with an embodiment of the invention. The liquid delivery system has multiple interconnected water circuits forming a fluid network between spaced pressure vessels; a liquid treatment system; and a control system to control the flow of water through the water circuits to substantially minimize water wastage and substantially maximise energy efficiency at a tap end when hot water is called for.

[0032] The system of the invention provides substantially instant access to hot water from a tap without having to prolong cold water egress before experiencing warmed and hot water. This represents an improvement over existing water treatment systems and benefits from very significant water savings and energy costs.

[0033] On a hot water delivery system having a connected fluid network in a sealed water heating system, there is provided a first pressure vessel 21 and a second pressure vessel 22 at spaced positions and each fluidly connected with a liquid treatment system

15 shown in the embodiments as a water heater. A plurality of delivery ports such as taps/faucets 17 are located along the fluid network proximal the second pressure vessel.

[0034] The fluid network of the delivery system includes a first piping 32 for circulating liquid to be treated between the first pressure vessel 21 and the connected liquid treatment system 15; a second piping 33 for circulating treated liquid between the liquid treatment system 15 and the connected second pressure vessel 22; and a third piping 34 interconnecting the first and second piping, wherein the third piping includes an intermediate valve means 41 ; a pump operable in one or more modes of operation; and a flow controller 40 for controlling the intermediate valve means and pump; wherein a plurality of piping circuits are provided by the fluid network for delivery of treated water in one of multiple modes of operation between the first and second pressure vessel.

[0035] Figures 4 to 8 show different modes of operation of the delivery system. In a first mode (M1 ) of operation (see Figure 4), the delivery system is in a priming or filling mode in which the fluid network is ready to receive an inflow volume of water from inlet

16 through inlet piping 31. Flere the second pressure vessel 22 is initially set by a diaphragm having an air pressure Pi corresponding to inlet water pressure, and the first pressure vessel 21 is set by a diaphragm at an air pressure P2 which is at least 50% lower than the air pressure set in second pressure vessel 22. The size and preselected set pressure differential of the first and second pressure vessels determines the volume of water movable back and forth in the fluid network between the first and second pressure vessels.

[0036] In the priming mode M1 of operation, the control valve 41 is open and the pump is not running. When inlet 16 is open, cold water flows from a domestic source in direction A through a non-return valve 161 into inlet piping 31 and into piping 32, 33 and 34. As the set air pressure P2 in the first pressure vessel is less than the set air pressure Pi, cold water entering the fluid network is urged into the first pressure vessel 21 and the liquid delivery system is filled (primed) with cold water. As water fills the first pressure vessel

21 air pressure P2 increases and priming mode M1 is reached when Pi and P2 have equilibrated. At this point, the system is in a standby mode with a store of cold water in the first pressure vessel 21 and where there is no flow within the fluid network.

[0037] Turning to Figure 5, there is shown the system in a circulation operating mode M2, where the control valve 41 is open and pump 46 switched on by controller 40, to allow flow of water in a first waterflow circuit Ci within the fluid network circulating water through the liquid treatment system 15 to treat by heating an initial volume of water in Ci. In one embodiment, the liquid treatment system 15 is a heater which is automatically started by waterflow therethrough hence flow of water in Ci initiates operation of the heater 15.

[0038] Referring to figure 6, there is shown a first pulsed operating mode M3. At a predetermined time or temperature or pressure, in mode M3 control valve 41 is closed and untreated or cold liquid stored in the first pressure vessel 21 is drawn by pump 46 and pushed to the second pressure vessel 22 through the liquid treatment system 15 following a second fluid circuit C2 between the first and second pressure vessels. Treated (heated) liquid/water in the first circuit Ci from mode M2 is pushed into the second pressure vessel 22 along piping 33 and as further liquid is drawn from the first pressure vessel 21 and pushed along piping 32 and 33 and through the heater 15, the temperature of the volume of liquid in circuit C2 is raised and with continued flow of liquid in circuit C2 a progressively increasing volume of heated liquid is received by the second pressure vessel 22. As the volume of heated/treated fluid increases in the second pressure vessel 22, the air pressure in the second pressure vessel progressively increases and the air pressure in the first pressure vessel 21 progressively decreases.

[0039] As shown in figure 7, at a predetermined time or pressure or temperature, controller 40 stops the pump 46 from running and opens control valve 41 in mode M4 to form a third circuit C3 for returning treated/heated liquid from the second pressure vessel

22 to the first pressure vessel 21 to provide a store of treated/heated fluid in the first pressure vessel 21 . As treated liquid from the second pressure vessel 22 returns to the first pressure vessel 21 , the air pressure in the second pressure vessel decreases and at the same time increases in the first pressure vessel. [0040] Figure 8 shows a standby mode M5 where control valve 41 and pump 46 are closed and turned off and the first pressure vessel filled with treated liquid and the air pressure in the first and second pressure vessel equilibrated. Figure 8 therefore represents a second standby mode M5 where further timed pulsing can occur subsequently at predetermined times to push treated/heated liquid between the first pressure vessel and the second pressure vessel. As also shown in figures 4 to 8, there can be multiple taps 117 and multiple second pressure vessels for each tap. In this case, each tap has immediate access to treated liquid from the second pressure vessel. This represents a significant improvement over prior art systems with less water wastage for example when hot water is desired and energy savings. The water heater 15 can be gas or electric water heater or oil or solid fuel or can be supplemented or replaced by a solar water heater fluidly connected into the sealed water heating system.

[0041 ] The liquid delivery system has at least one flow controller 40 which selectively controls the flow of liquid through the first piping and the second piping by effecting selective operational steps of:

• A system setup step

• A priming step

• A treatment step

• A distribution step

• A diversion step [0042] The system has a) a first piping 32 which extends from the first pressure vessel 21 to the water heater 15 and receiving connection from the infeed piping 31 connected to a supply 16 of cold water. The first piping allows for circulating liquid to be treated between the first pressure vessel fluidly and the connected liquid treatment system of the hot water heater 15; b) a second piping 33 extends from the connected liquid treatment system of the hot water heater 15 to outlets 17 along for circulating treated liquid between the liquid treatment system and the connected second pressure vessel 22; c) a third piping 34 extending between piping 32 and 34 and including a control valve 41 for controlling flow of liquid in circuits Ci, C2 and C3. [0043] To enable the required flows the at least one flow controller 40 includes: a) a flow switch being a solenoid 41 for selectively controlling the flow through the first piping 32 and the second piping 33 b) a timer or remote control for providing timed changes (not shown) c) a pressure control of creating differential pressure between the pressure in first pressure vessel 21 and second pressure vessel 22.

[0044] Example 1 - Diversion

[0045] The first and second pressure vessels operate at different pressures and the size and system pressure can be adjusted.

[0046] For example, in one form the system is set up with a) Cold water inlet with pressure reducing valve, set for 40 PSI. b) First pressure vessel diaphragm P1 pressure set for 20 PSI. c) Second pressure vessel diaphragm P2 set for 40 PSI.

[0047] As shown in Fig 8, the pressure differential can be augmented, supplemented or replaced by pumps 46 in the first or second pipings 32, 33. These pressure differentials can be effected. Therefore, there is differential pressure Pi in first pressure vessel 21 , to the pressure P2 in the remote second pressure vessel 22 near the tap outlets 17 and in comparison to the pressure P3 in the water heater 15 that can be augmented by the pressure P4 of the pump 46.

[0048] Treatment Step

[0049] Referring to Fig 5, in the treatment step mode M2, there is affected circulation of liquid to be treated in a circuit Ci through the first piping 32 to enable treatment in the water heater 15 of the liquid treatment vessel of the liquid treatment system. Therefore, the solenoid 41 is open in the piping 34 and the pump 46 is running which allows circulation of water back to the water heater 15 until water is fully heated in piping 32 in circuit Ci.

[0050] The following is 'After system is filled with water'. With system at rest (standby mode), as no hot water is in demand and no flow within the piping network, a diaphragm in first pressure vessel 21 with the lower pressure setting is now compressed to 40 PSI and is part full of water. The second pressure vessel 22 has no water in it due to the higher set pressure. [0051] Upon demand for hot water either by the time-switch or remote control, the pump 46 fitted with a pressure switch and non-return valve, turns on. This circulates the water in circuit Ci through the water heater 15 and back to the pump via the solenoid valve 41 that is in an open position, water is then heated to a control set temperature T 1 . [0052]

[0053] Distribution Step

[0054] Referring to Fig. 6, there is shown a distribution step, operating mode M3, with solenoid valve shut and pump running, where liquid is distributed in a pulsed effect in a circuit described by C2 that has been treated through the second piping 33 to the second pressure vessel 22 to replace untreated/cold liquid in the second piping with treated or partially treated liquid.

[0055] After approximately 30 seconds of the circulation or treatment mode M2 (figure 5), the control timer 40 shuts the solenoid valve 41 and the pump 46 begins to run in mode M3.

[0056] As shown in figure 6, the Pump 46 now draws water from the first pressure vessel 21 and pumps the water pressure up to 60 PSI. (Pump 46 stops when a set pressure is reached.) The additional water can only flow into the system via the hot water heater, and then on to part fill the second pressure vessel 22. As the flow from the water heater 15 is now up to temperature, there is now an instant flow of hot water to the tap/faucet 17 located close to the pressure vessel 22 position.

[0057] The additional hot water flow pushes the cold water out of the pipework 33 and into the second pressure vessel 22 The hot and cold water in pressure vessel 22 separates due to the different density with the cold water at the bottom. [0058]

[0059] Diversion (return) Step

[0060] Referring to Fig. 7, in the diversion step in mode M4 there is affected a third circuit C3 enabling a return of at least some untreated liquid from the second piping 33 and from the second pressure vessel 22 to the first pressure vessel 21 via piping 34 with the pump 46 not running.

[0061] Following a timed two-minute period in mode M3 (figure 6), solenoid valve 41 returns to an open condition in mode M4 affecting the return to the first pressure vessel 21 as above.

[0062] In the return or diversion step, water in second pressure vessel 22 being cold water first (i.e. cold water at the lower end thereof) is pushed back into second piping 33 and third piping 34 by the extra pressure compared to the first pressure vessel 21 , which is now at lower pressure. [0063] The system comes to rest at 40 PSI when the second pressure vessel 22 is empty and first pressure vessel 21 is part full. This is referred to as a standby mode in which there is no flow of liquid in the piping network and in which there is a store of treated liquid in the first pressure vessel. In standby mode M5, the treated liquid in the first pressure vessel 21 is ready for further treatment in the water heater 15 of the liquid treatment vessel of the liquid treatment system in circuit Ci and C2.

[0064]

[0065] After a short period of time in a standby mode, such as approximately twenty- minutes, the treatment cycle repeats until the controller turns off so that the water temperature is substantially maintained in circuit Ci and ready for transfer in a pulsed operating mode for use in the second pressure vessel 22.

[0066] Fig 8 shows the use of a one-way pump 46 to provide further pressure P4 to drive the liquid from the first tank 21 at pressure P1 to the heating tank 15 at pressure P3. This enhances the differential pressures P1 , P2 P3 and P4 to effect the required flows.

[0067] Figs. 9 to 16 illustrate a further example of a liquid delivery system in accordance with some embodiments of the invention. The liquid delivery system in the form of a hot water system 100 comprises a liquid treatment system having a heater tank 115 for heating water within the system 100 introduced from a cold water supply 116. A first pressure vessel 121 is selectably fluidly connected to the liquid treatment system, and a second pressure vessel 122 near a delivery port (not shown) is selectably fluidly connected to the liquid treatment system. Figure 9 shows an empty system waiting to be primed, and wherein the air pressure Pi in the second pressure vessel is set at about the same pressure at the inlet 116 and the air pressure P2 of the first pressure vessel is set at least 50% lower than Pi. The system further comprises a flow controller 140 for selectively controlling flow between the first and second pressure vessels 121 , 122 and the heater tank 115.

[0068] Referring to Fig. 9 showing the setup step prior to filling the hot water system 100 with cold water supply 116, the system is empty of water. Air pressures in the first and second pressure vessels 121 , 122 are preset to initial levels where the first pressure vessel is preset to approximately half of the inlet water pressure of the cold water supply 116. The second pressure vessel is preset to be approximately similar to the water pressure of the cold water supply 116.

[0069] As shown in Fig. 10 once the pressures of the pressure vessels have been set, the system 100 is connected to a cold water supply 116 filling the system 100 with cold water. The first pressure vessel 121 fills with cold water to equalize the preset air pressure with the water pressure of the cold water supply 116. However, because the preset air pressure of the second pressure vessel 122 is similar to the pressure of the water supply, the second pressure vessel 122 does not fill with water, remaining substantially empty. This mode of operation may be referred to as the system filling or priming step. In the priming step control valve 141 is open and pump 146 is not operating.

[0070] Once the liquid delivery system is filled with cold (untreated) water W _u air pressure in the first and second pressure vessels equalize and a volume of untreated water W _u sits in the system in a standby or static flow mode.

[0071 ] The priming step does not require operation of the pump as water flows within the system 100 by pressure differential between the first and second pressure vessels, and at this stage the control valve 141 , which can be a solenoid valve, is open. The system 100 is filled with a supply of cold water once the air pressure in the first pressure vessel reaches the water pressure of the cold water supply 116. As seen, the volume of cold water in the first pressure vessel is increased storing a predetermined volume with corresponding increase in air pressure. At the same time because the air pressure in the second pressure vessel is set at inlet water pressure, the second pressure does not fill and a volume of cold water is received by the delivery system dependent on the size of the circuit and pressure vessels and set pressure differentials. The size of the circuit and pressure vessels and set pressure differentials determines the volume of water that can be moved back and forth.

[0072] Once the system has been filled or ‘primed’ (figure 10), the water delivery system is in a standby mode ready for the water treatment circulation step to start (fig. 11). For the embodiment shown in figure 11 the pump 146 is running and the solenoid valve is open. As water starts to flow in a first circuit, water treatment comprises initially heating the water received in the heating tank 115 during the priming step and circulating water in a first circuit Ci along piping 131 and 132. Additional water can therefore be heated to an initial temperature Wu by circulating the water along piping 132 through the open solenoid valve 141 and pumping water through the heating tank 115 using pump 146. This operation may be referred to as the circulation step.

[0073] Once the water being circulated in the circulation step reaches the predetermined treatment temperature Wu, the control valve in this case a solenoid valve 141 is closed in a third mode of operation and water stored in the first pressure vessel is pumped from the first pressure vessel 121 to the second pressure vessel through a second circuit C2 via the heater tank 115 as shown for example in Figure 12.

[0074] In this step (refer figure 12), cold or untreated water stored in the first pressure vessel is drawn from the first pressure vessel 121 and displaces the treated water in the heater tank 115 and using increased pressure from the pump 146 treated water is pushed along the piping 132 and 133 into the second pressure vessel 122 at a temperature Wt2. Importantly faucets (not shown) arranged along the pipeline between the heating tank 115 and the second pressure vessel 112 now provide treated water Wt2 when opened. This can be referred to as the warm water storage stage.

[0075] When the second pressure vessel is filled with hot water, or if the water temperature in the second pressure vessel begins to drop, the solenoid valve can be opened, and the pump can be switched off. As a result, as shown in Fig 13 treated water in the second pressure vessel 122 will begin to flow back into the first pressure vessel through a further circuit due to the pressure differential existing between the second and first pressure vessels.

[0076] In this embodiment, hot water is returned from the second pressure vessel to the first pressure vessel by increased air pressure in the second pressure vessel, to stabilize the delivery system. The first pressure vessel progressively fills with a volume of hot (treated) water until the air pressure in both pressure vessels in substantially the same. Treated water can be selectively moved within the circulation circuit by opening the control solenoid valve and operating the pump in essence for priming the treated water within piping 132 for further movement from the first pressure vessel to the second pressure vessel.

[0077] In figure 13, there can still be seen some residual untreated (cold) water W _u in the first piping. Following the step in figure 13, the delivery system is placed into a further circulation step using circuit Ci with open valve and heating, to treat water in Ci and bringing the water to a temperature Wt2. [0078] Referring to figure 15, the system is shown in a pulse mode of operation in the second circuit C2 showing all liquid has been treated to Wt2 and the treated liquid within the delivery system 100 is pushed by the pump from the first pressure vessel 121 to the second pressure vessel 122 through the heater 115 with solenoid valve in a closed position.

[0079] In figure 16, the system is back to standby mode where the pump is not running, and the solenoid valve is open. In this condition, the first vessel is part full, and the second pressure vessel is empty.

[0080] Advantageously by switching between the recirculating, storing and returning operational stages, water can be circulated though the piping and particularly through the heater tank 115 to ensure that the water maintains the required treated temperature ensuring that untreated water is not wasted when opening a faucet.

[0081] Fig 17 is an example of the method of liquid delivery system for supplying treated liquid at a delivery point in which in a first step of providing a flow switch being a solenoid for selectively controlling the flow through the first piping and the second piping, a timer or remote control for providing timed changes, and a pressure control of creating differential pressure between the pressure in first pressure vessel and second pressure vessel.

[0082] In a second step there is the step of controlling flow through a first piping for circulating liquid to be treated between the first pressure vessel fluidly and the connected liquid treatment system or a second piping for circulating treated liquid between the liquid treatment system and the connected second pressure vessel

[0083] The further step includes a treatment step of circulating liquid to be treated through the first piping to enable treatment in the liquid treatment vessel of the liquid treatment system.

[0084] A still further step has a distribution step of circulating liquid that has been treated through the second piping to the second pressure vessel to replace untreated liquid in the second piping with treated or partially treated liquid.

[0085] Another step has a diversion step of returning at least some untreated liquid from the second piping to the first pressure vessel to enable treatment in the liquid treatment vessel of the liquid treatment, [0086] These steps are undertaken again back from the second step if further treatment and supply is required until the required supply is met.

[0087] Referring to Fig 16 there is shown an example of the overall hot water system modified to form liquid delivery system in the form of a hot water system in accordance with an embodiment of the invention

[0088] A particular embodiment is shown in Fig 18 that includes solar heating from solar panels 49 that feeds cold water from the cold-water supply to the panels 49 and after heating transfer the heated water to the top of hot water heater 15.

[0089] Referring to Fig. 18, should there be a loss of water in the system and it could not be pressurised, the pressure switch 11 would stop pump 46 and returns solenoid valve 41 back to open. Should hot water be drawn off, as the pressure pulse mode is taking place, flow switch 12 would detect usage and returns the pressure pulse system to rest.

[0090] The diaphragm pressure in pressure vessel 21 forces water into the suction inlet of pump 46 when in pressure pulse mode.

[0091 ] On first start-up, the unit would be programmed to pulse several times for fast delivery of hot water to tap/faucet positions before entering cycling mode.

[0092] It should be noted that water heaters without storage can work up to 145 PSI.

[0093] It should be noted that there is substantial volume of water in the piping 33 that needs to be taken into consideration in the heating or treating system. These volumes can be of the order of:

[0094] Conversion of standard hot water system

[0095] Referring to Figs 19 to 23 there is shown the requirements to convert a standard hot water system such as shown in Fig 1 to an operative delivery system in the form of a hot water system in accordance with an embodiment of the invention including supporting pressure pumps and diaphragm pressure vessels.

[0096] It can be seen in Fig 19 and in the simpler system of Fig 20 that the difference to the standard hot water supply is by addition of parts A and B.

[0097] Part A includes the step of inserting a first pressure vessel 21 at or near a cold- water inlet feed to the hot water tank 15 and Creating a controlled diversion flow piping between the hot water heater the first pressure vessel and the inlet to the hot water heater [0098] Part B includes the steps of Inserting a second pressure vessel 22 by a T connection at or near a delivery outlet at or near an end of supply line from the hot water heater to the delivery outlet (such as shown in Figs 22 and 23) and adding piping to effect a controlled circulating diversion flow

[0099] A controller 45 controls flow with the first pressure vessel 21 or selectively effects flow to the second pressure vessel 22 and thereby to a delivery outlet 17.

[00100] The controller can include a remote control or a timer control. a) Remote control system is required to switch the pump/boost compressor on to charge the system up to pulse pressure with pressure switch to cut out at correct set pressure. b) Timers are used to switch the pressure pulse system on/off at selected times, and controls the time periods the pulse pressure is held.

[00101] The method of modifying a hot water system wherein one or more of the first or second pressure vessels can use diaphragm pressure vessels such as shown in Figs 19 to 21 In liquid/water applications, pressure vessels with diaphragms would be required in both vessels to keep the contents in the system under pressure and free from contamination.

[00102] The diaphragms are also needed when system pulse pressure is released to push the water/liquid back to the pressure vessel P1 ready for the next pulse.

[00103] The diaphragm pressure vessels could be bladder, spring, air pressure, bellows, operated to achieve the oscillating pressure and movement of the water/liquids/chemical solutions/air/nitrogen/other gases in the pipelines.

[00104] Figure 21 shows a purpose-made pressure vessel to fit back of sinks/bathrooms to suit all pipework water volumes in domestic installations.

[00105] Figure 22 has Pressure vessels at pulse pressure, system fully charged. 21 pressure vessel part empty and 22 pressure vessel part full.

[00106] Figure 23 shows a pressure vessel at rest (standby) 21 , pressure vessel has the water/liquid returned to it, and the pressure vessel 22, has discharged its contents. System now at normal working pressure.

Fire Sprinkler System

[00107] In another application of the invention there is use of the pressure pulse system for a fire sprinkler systems of which there are a number of types of sprinkler systems.

[00108] There are four main fire sprinkler systems. The invention works particularly with one of them. The four types are: a) Wet Pipe Commercial Sprinkler System b) Dry Pipe Commercial Sprinkler System c) Pre-Action Commercial Sprinkler System d) Foam Water Commercial Sprinkler System

On wet systems the pressure pulse system would use water as the operating vehicle with pump system. Dry systems would use compressed air/nitrogen as the vehicle with boost compressor.

[00109] Wet Pipe Commercial Sprinkler System

[00110] Wet Pipe Systems include overhead piping filled with water under pressure. Once a fire activates a sprinkler head, water immediately discharges to flood the fire. Wet pipe systems are the most common mostly due to their simplicity and reliability. They also have relatively low installation and maintenance costs. But problems can arise in temperatures under 40° Fahrenheit (about 4.444° Celsius) and can freeze. Pressure Pulse Systems could keep exposed areas of pipework above freezing temperatures.

[00111 ] Dry Pipe Commercial Sprinkler System

[00112] Instead of having pressurized water throughout the entire system of sprinkler piping, dry pipe sprinkler systems are only filled with air or nitrogen indirect, non-heated piping. When a fire activates a sprinkler, water is then released into the piping system to discharge onto the fire. Dry piping systems work well in spaces with freezing temperatures. But they are more costly to maintain and may have a delay of up to 60 seconds until water is discharged. Pressure Pulse Systems could be used to remove moisture from the pipelines to avoid corrosion.

[00113] Pre-Action Commercial Sprinkler System

[00114] In some spaces, specific circumstances can trigger a sprinkler by accident. Pre-Action sprinkler systems are a type of dry system where water is held back by a pre action valve. For the valve to open, a detected fire must activate the pre-action valve. Then each fire sprinkler head is opened individually. These systems are great for spaces with sensitive equipment or costly materials. But these systems are more complex in design, pricier to install, and more expensive to maintain. Pressure Pulse Systems could be used to remove any subsequent moisture from the pipelines to avoid corrosion.

[00115] Foam Water Commercial Sprinkler System

[00116] Water is often used for fire sprinkler systems because of its simplicity. But for certain types of fires, it is not the best resource. Foam water fire sprinkler systems mix water with a foam concentrate mix that flows through the pipe to extinguish the fire. Foam is necessary when putting out flammable solvent fires like gas or alcohol. It can quickly suffocate fumes and eliminate the chance of re-flash. Pressure pulse systems could be used for keeping the foam concentrates evenly mixed throughout the pipeline.

[00117] Use of Pressure Pulse System on Dry Pipe Commercial Sprinkler System

[00118] Referring to Fig 24 there is shown system for pressure pulse system used for a dry fire sprinkler system as an embodiment of liquid delivery system in accordance with the invention. In figure 24, reference numerals 110, 111 and 112 are manual valves and 101 , 102, 104, 105, 106 and 107 are normally closed solenoid valves, and 103 is a non return valve.

[00119] The system includes

[00120] In the operation of the pressure pulse system for a dry fire sprinkler system there is the steps on first commissioning of:

• Manual valve 110 is open, manual valves 111 and 112 are shut

• Main compressor 109 turns on and charges the pipework system and storage vessels 113 and 114 to 20 PSI with all air passing through the dryer 115.

• At 20 PSI manual valve 110 is shut, manual valves 111 and 112 are opened and boost compressor 108 is turned on manually.

• This takes air from the pipework system via the manual valve 112 and pressurises the storage tanks 113 and 114 to 80 PSI.

• Any additional air taken from the pipework system is being replaced by main compressor 109, if required.

[00121] At 80 PSI boost compressor 108 is manually turned off.

• Manual valves 111 and 112 are shut, system at rest with 20 PSI in main pipework and 80 PSI in storage vessels 113 and 114.

• Pressure Pulse System Ready To Turn On:

• At timed period valves 102,105, and 106 open, the excess pressure forces air flow from storage vessels 113 and 114 through dryers 115, and into the main pipework system to part fill receiver vessels 116.

• When system is stabilised, at say 50 PSI, valve 106 shuts and valve 107 opens.

• Boost compressor 108 turns on and takes the additional air from storage vessels, 113 and 114 and charges the main pipework system to 80 PSI.

• At this point all the stagnant and moist air from the pipework is contain in the receiver vessels 116.

• The storage vessels 113 and 114 are down to 20 PSI, and the mains system pipework is at 80 PSI. Valves 102 and 107 shut, system holds in this position to allow any moisture in pipework to dry out.

• After timed period valves 101 and 106 open, air now flow back from system and receivers 116 to storage vessels 113 and when stabilised, at say approx., 50 PSI, valve 105 shuts, valve 104 opens, boost compressor 108 turns on and takes the additional air from main pipework system and pressurises the storage vessels 113 and 114 back up to 80 PSI, leaving the main pipework system at 20 PSI. The receiver vessels 116 diaphragms are back down to 20PSI and the diaphragm pressure has forced all additional air out of the pipelines back to storage vessels 113 and 114

• Valves 101 and 104 now shut.

• System at rest.

• At set required time the pressure pulse system repeats the operation.

[00122] Referring to Fig 25 there is shown a system for pressure pulse system used to keep compressed air/nitrogen to optimal moisture content levels as an embodiment of liquid delivery system in accordance with the invention. The fire sprinkler industry use compressed air/nitrogen and dryers are used to control oxygen corrosion and reduce moisture content in dry and pre-action fire sprinkler systems.

[00123] The Pressure Pulse System can be used to keep moisture at optimal level by oscillating the air/nitrogen in single pipelines, back and forth from the dryers and point of use. The same method could also be used on compressed airlines in manufacturing plants where the moisture content is critical. And for drying out small pipelines before use by oscillating dried compressed air/nitrogen between two fixed points.

[00124] In air/nitrogen applications, the pressure vessel P1 would not need a diaphragm fitted, as air/nitrogen is compressible but water is not. However, pressure vessels P2 would require a diaphragm to force out all the additional air/nitrogen that had been added to the pipelines under the pulse pressure mode.

[00125] This oscillating of the water/liquid/air/nitrogen in the single pipe lines is the medium that is used to heat/cool/dry the pipelines at point of use.

[00126] Figure 26 shows an apparatus according to a further embodiment of the present invention installed on a cold mains water supply to chill the service pipework to 20 degrees C and below to comply with health regulations and avoiding legionella bacteria which optimally grows at temperatures between about 20 - 45 degrees C. [00127] Figure 27 Pressure Pulse system installed on an existing hot water system in commercial premises such as hotels and the like fitted with a conventional hot water circulating pipework. This type of installation substantially eliminates loss of water from dead legs and brings the wait time for hot water down to seconds.

[00128] Figure 28 shows a further embodiment of the present invention installed in a reverse position with the storage vessel (first pressure vessel) inside a premises and the receiver vessel (second pressure vessel) at the water heater position. In this application there is no increase in water pressure on the service pipework as the receiver vessel receives the additional pressure and the water from the storage vessel. No pressure reducing valve required on the cold-water supply pipework. One operating pulse mode will take hot water up to temperature. One Example, storage vessel holds four litres of water and the pipework three litres, the apparatus in pulse mode transfers three litres into the receiver vessel from the pipework. The cold water in the storage vessel now replaces the water taken out of the pipework, when the system returns to standby mode. Three litres of hot water are returned, the three litres of cold water is now returned to the storage vessel and three litres of hot water is in the pipework at the tap/faucet point, and the cold water in the storage vessel is held in place by the system standing pressure.

Interpretation

Embodiments:

[00129] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.

[00130] Similarly it should be appreciated that in the above description of example embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the Detailed Description of Specific Embodiments are hereby expressly incorporated into this Detailed Description of Specific Embodiments, with each claim standing on its own as a separate embodiment of this invention. [00131] Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

Different Instances of Objects

[00132] As used herein, unless otherwise specified the use of the ordinal adjectives “first”, “second”, “third”, etc., to describe a common object, merely indicate that different instances of like objects are being referred to and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.

Specific Details

[00133] In the description provided herein, numerous specific details are set forth. Flowever, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Terminology

[00134] In describing the preferred embodiment of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. Flowever, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as "forward", "rearward", "radially", "peripherally", "upwardly", "downwardly", and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms.

Comprising and Including

[00135] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

[00136] Any one of the terms: including or which includes or that includes as used herein is also an open term that also means including at least the elements/features that follow the term, but not excluding others. Thus, including is synonymous with and means comprising.

Scope of Invention [00137] Thus, while there has been described what are believed to be the preferred embodiments of the invention, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the scope of the invention. For example, any formulas given above are merely representative of procedures that may be used. Functionality may be added or deleted from the block diagrams and operations may be interchanged among functional blocks. Steps may be added or deleted to methods described within the scope of the present invention.

[00138] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

Industrial Applicability

[00139] It is apparent from the above, that the arrangements described are applicable to the fluid treatment and supply industries and particularly hot water supply and dry fire sprinkler systems.