System and method for regulating the temperature of a disinfection fluid for water treatment

Abstract

A system for regulating temperature of a disinfection fluid for water treatment. The system comprises: a storage tank configured to hold the disinfection fluid; a heat exchanger in fluid communication with the storage tank, and which is configured to cool the disinfection fluid as the disinfection fluid passes through the heat exchanger. In particular, the system further comprises a chilled fluid flow path thermally coupled to an outer surface of the storage tank, enabling a chilled fluid flows along the outer surface of the storage tank and dissipates heat from the disinfection fluid stored therein. The invention also provides a method for using such system.

Description

1 SYSTEM AND METHOD FOR REGULATING THE TEMPERATURE OF A DISINFECTION FLUID FOR WATER TREATMENT TECHNICAL FIELD Embodiments of the present invention relate to disinfection of potable water. More particularly, embodiments of the present invention relate to a system and method for regulating the temperature of a disinfection fluid used in water treatment. BACKGROUND OF THE INVENTION An edible sterilizer, such as a disinfection fluid commonly used in water treatment, is known to be highly temperature-sensitive. When the storage temperature rises, chemical degradation accelerates, rendering the sterilizer less effective or unsuitable for treating potable water. For example, in the case of sodium hypochlorite solution, an increase in temperature leads to a decline in available chlorine concentration and an increase in chlorate formation, thereby reducing and destabilizing its disinfection performance. Under warm storage conditions, particularly in hot climates, the usable life of the solution may be limited to a relatively short period, for example on the order of about seven days, depending on the installation. Cooling the disinfection fluid can significantly prolong its usable storage life by better preserving the available chlorine content and limiting chlorate accumulation. In practice, the temperature within the storage tank fluctuates due to ambient heat gain, solar exposure, rainfall, transfer operations, changes in inventory, and the thermal inertia of the liquid. Conventional cooling systems typically treat the tank as a single thermal mass and rely on fixed setpoints or basic feedback control. Such approaches are often inadequate when the dominant heat source shifts between continuous wall heat ingress and short process disturbances, particularly during refilling, low-load periods, or sudden changes in weather conditions. Embodiments of the present invention thus aims at providing a system and a method for regulating the temperature of the disinfection fluid, in order to alleviate at least one of the aforementioned deficiencies of the prior art. SUMMARY OF THE INVENTION According to a first aspect of the present invention, there is provided a system for regulating temperature of a disinfection fluid for water treatment, comprising: a storage tank configured to hold the disinfection fluid; a heat exchanger in fluid communication with the storage tank, and configured to cool the disinfection fluid as the disinfection fluid passes through the heat exchanger; wherein the system further comprises a chilled fluid flow path thermally coupled to an outer surface of the storage tank, enabling a chilled fluid flows along the outer surface of the storage tank and dissipates heat from the disinfection fluid stored therein. In an embodiment, the system comprises a chilled-fluid generation unit configured to supply the chilled fluid to both the heat exchanger and along the chilled fluid flow path. In an embodiment, the system comprises a first circulation loop in which the disinfection fluid flows through at least the storage tank and the heat exchanger, and a second circulation loop in which the chilled fluid flows through at least the heat exchanger and the chilled fluid path. 1 HK 30137919 A 2 In an embodiment, each of the first and the second circulation loops comprises one or more flow regulating means configured for varying a flow rate of the fluid within respective circulation path. In an embodiment, the one or more flow regulating means is selected from the group comprising a variable speed drive circulation pump, a flow valve, a flow restrictor, and a combination thereof. The circulation pump is a variable speed drive circulation pump. In an embodiment, the system further comprises a flow regulating unit to control and vary the flow rate of at least one of the disinfection fluid and the chilled fluid, based at least in part on parameters measured by one or more sensors deployed in the system. In an embodiment, the one or more sensors comprise a first group of sensors configured to collect flow parameters of at least one of the disinfection fluid and the chilled fluid, the first group of sensors being selected from the group comprising a temperature sensor, a flow meter and a combination thereof. In an embodiment, the one or more sensors comprise a second group of sensors configured to collect ambient data externally of the first circulation loop and the second circulation loop. In an embodiment, the second group of sensors is selected from the group consisting of a wind sensor, a humidity sensor, a rainfall detector, a solar exposure detector, and combinations thereof. In an embodiment, at least one of the sensors is configured to collect data at a predetermined time interval. In an embodiment, wherein the chilled fluid flow path comprises a pipe wounded around the outer surface of the storage tank. In an embodiment, the disinfection fluid comprises sodium hypochlorite. According to a second aspect of the present invention, there is provided a method for regulating temperature of a disinfection fluid for water treatment, comprising steps of: storing the disinfection fluid in a storage tank, and circulating the disinfection fluid through a heat exchanger; wherein the temperature of the disinfection fluid stored within the storage tank is further regulated by flowing a chilled fluid along a chilled fluid flow path that is thermally coupled to the storage tank, thereby dissipating heat from the disinfection fluid stored therein. In an embodiment, the method further comprises passing the chilled fluid through the heat exchanger to regulate the temperature of the heat exchanger. In an embodiment, the method further comprises acquiring one or more fluid parameters of at least one of the disinfection fluid and the chilled fluid to determine regulation of flow thereof, wherein the one or more fluid parameters are selected from the group comprising temperature, flow rate, and a combination thereof. In an embodiment, the method further comprises acquiring one or more ambient parameters of an external environment to determine regulation of flow of at least one of the chilled fluid and the disinfection fluid, wherein the one or more 2 HK 30137919 A 3 ambient parameters are selected from the group comprising ambient temperature, humidity, rainfall, wind condition, solar exposure, and a combination thereof. In an embodiment, the method further comprises: acquiring the temperature of the disinfection fluid stored in the storage tank; and upon detecting that the temperature of the disinfection fluid exceeds a predetermined threshold value, increasing the circulation speed of at least one of the disinfection fluid through the heat exchanger and the chilled fluid through the chilled fluid flow path, to maintain the temperature of the disinfection fluid within a predetermined range. In an embodiment, the temperature of the disinfection fluid is maintained within a range of about 18.5°C to 20.0°C during daytime operation when solar load is present. In an embodiment, the temperature of the disinfection fluid is maintained within a range of about 16.0°C to 17.5°C during night-time operation in the absence of solar load. In an embodiment, during a refill operation in which a volume of the disinfection fluid in the storage tank increases by more than 50% within one hour, the temperature of the disinfection fluid is maintained within a range of about 17.5°C to 18.5°C. According to a further aspect of the present invention, there is provided a system comprising a dual-path cooling architecture for sodium hypochlorite solution storage used in water treatment sterilization, wherein a shared chiller side supplies both a tank cooling jacket branch and a process heat-exchanger branch, and wherein the process recirculation loop includes one or more variable-speed recirculating pumps. In an embodiment, the plant state and ambient load are classified, cooling duty is allocated between the branches, process recirculating pump speed and branch flow- regulating elements are modulated, and chiller-side equipment-protection constraints are enforced. In an embodiment, other parameters including weather-state classification, refill-state recognition, dynamic dead band management for staged dual-compressor protection, protected degraded mode, local validation before actuator execution, sensor plausibility checking, and fouling detection by thermal-performance indicators are considered for cooling the sodium hypochlorite solution. Embodiments of the present invention provide a system and method for regulating the temperature of a disinfection fluid used in water treatment. The system maintains the storage temperature of the temperature-sensitive disinfection fluid within an optimal range by circulating the fluid through a heat exchanger and passing a chilled fluid along the outer surface of the storage tank, thereby slowing its degradation and extending its shelf life. BRIEF DESCRIPTION OF THE FIGURES Embodiments of the present invention will now be described, by way of examples only, with reference to the accompanying figures in which: Fig. 1 is an illustration of an embodiment of a system for regulating temperature of a disinfection fluid used in water treatment, according to the present invention; 3 HK 30137919 A 4 Fig. 2 is a block diagram of an embodiment of the temperature regulating system of Fig. 1; Fig. 3 is a flow chart of an embodiment of a method for regulating temperature of a disinfection fluid used in water treatment, according to the present invention; and Fig. 4 is a table showing performance data of the temperature regulating system in four different scenarios, according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS Described herein are, among other things, techniques for preserving and extending the lifespan of a disinfection fluid used in potable water treatment. A typical disinfection fluid, such as sodium hypochlorite solution, is highly sensitive to temperature and degrades significantly faster at elevated temperatures. The optimal storage temperature for sodium hypochlorite solution is around 15°C to 20°C. Maintaining this lower storage temperature substantially extends its shelf life and minimizes decomposition into oxygen gas. At around room temperature (20–25°C), the solution is acceptable for short-term storage. However, noticeable degradation occurs over weeks or months. Above 30°C, the rate of decomposition increases significantly. For example, raising the storage temperature from 25°C to 35°C can reduce the shelf life by approximately three times. In an embodiment, other disinfection fluids including calcium hypochlorite and chloramines may be used. Embodiments of the present invention relate to a system and a method for regulating the temperature of a disinfection fluid used in potable water treatment, thereby enhancing its stability and prolonging its shelf life. Fig. 1 illustrates an embodiment of a system 100 according to the present invention. The system 100 comprises a storage tank 110 for holding the disinfection fluid. In an embodiment, the disinfection fluid is a sodium hypochlorite solution. Alternatively, other disinfection fluids including calcium hypochlorite and chloramines may be used. The storage tank 110 is in fluid communication with a heat exchanger 130, allowing the disinfection fluid to be circulated through the heat exchanger for cooling when required. The system 100 further includes a chilled fluid path 140 thermally coupled to an outer surface of the storage tank 110. The chilled fluid flows along the tank’s outer surface to dissipate heat from the stored disinfection fluid. In an embodiment, the chilled fluid path 140 comprises a pipe wound around the storage tank 110 to maximise the contact area. In an embodiment, the chilled fluid is supplied by a chilled-fluid generation unit 120. This unit circulates the chilled fluid through two separate paths: the chilled fluid path 140 on the outer surface of the storage tank 110 and the heat exchanger 130. This dual-path circulation effectively regulates the temperature of both the stored disinfection fluid and the heat exchanger itself, ensuring continuous and efficient cooling performance. Accordingly, the system 100 features two independent circulation loops, each carrying a different fluid. These loops are physically separated to prevent any mixing between the disinfection fluid and the chilled fluid. The first circulation loop transports the disinfection fluid. It enables the disinfection fluid to flow from the storage tank 110 through the heat exchanger 130, where heat is removed, and then returns the cooled disinfection fluid back to the storage tank 110. The second circulation loop carries the chilled fluid generated by the chilled-fluid generation unit 120. The chilled fluid circulates along the chilled fluid path 140 in thermal contact with the outer surface of the storage tank 110 and also passes through the heat exchanger 130 to absorb heat from both the tank and the heat exchanger. Each of the first and second circulation loops comprises flow regulating means configured to vary the flow speed of the fluid 4 HK 30137919 A 5 within its respective circulation path, allowing precise control over the cooling process and temperature regulation of the disinfection fluid. In an embodiment, the flow regulating means include, but are not limited to, a variable speed drive circulation pump, a flow control valve, and a flow restrictor. These components are configured to regulate the flow rate, direction, and movement of the fluid within each circulation loop according to operational requirements, thereby achieving optimal cooling performance and temperature control of the disinfection fluid. In a particular implementation as shown in Fig. 2, the cooling system 200 comprises a sodium hypochlorite solution storage tank 210 for water treatment disinfection duty, a tank cooling jacket 240 thermally coupled to the tank wall, a process-side heat exchanger 230 arranged to cool recirculating sodium hypochlorite solution, and a chilled-fluid generation unit 220 configured to supply chilled fluid to both the tank cooling jacket 240 and the process-side heat exchanger 230. The system 200 further comprises a jacket loop with at least one circulation pump and at least one flow-regulating element, a process recirculation loop with at least one variable-speed recirculating pump and at least one flow-regulating element, a sensor set including tank temperature, chilled-fluid temperature, branch-flow information, and ambient- condition information, a deterministic supervisory controller, preferably implemented by a PLC, and an equipment-protection logic layer including permissives, minimum- flow rules, restart delay rules, compressor protection, and abnormal-state fall-back logic. In an embodiment, the sensor set comprises a first group of fluid sensors, such as temperature sensors and flow meters, for measuring the parameters of the disinfection fluid and the chilled fluid. The sensor set further comprises a second group of ambient sensors, including a wind sensor, a humidity sensor, a rainfall detector, and a solar exposure detector. These ambient sensors measure the external environmental conditions in which the system is situated and provide feedback to the flow regulation system in response to the measured environmental parameters. The tank cooling jacket 240 and the process-side heat exchanger 230 perform different thermal functions. The branch of the tank cooling jacket 240 mainly removes distributed heat gain through the tank wall and responds to weather-driven load. The process-side heat exchanger 230 mainly removes sharper thermal disturbances, particularly during refill or during rapid rise in solution temperature. The plant is therefore arranged as a dual-path cooling system in which the two branches are assigned different thermal duties rather than treated as interchangeable loads. In an embodiment, the hydraulic arrangement follows the same division of function. The chilled-fluid generation unit 220 supplies both branches on a shared chiller side. Cooling duty is allocated between the jacket branch and the process heat- exchanger branch by coordinated adjustment of branch flow-regulating elements and, on the process side, variable-speed recirculation. In this arrangement, the process recirculation loop provides the faster corrective response, while the jacket branch provides steadier control of boundary heat ingress. On the chiller side, total evaporator-side flow serving the two branches may be fixed or may vary within defined limits, provided that the flow remains within the protected operating range required for minimum-flow protection, temperature protection, and compressor staging. In an embodiment, the regulation system features a coordinated control relationship among the shared chiller side, the jacket branch, the process heat- exchanger branch, the variable-speed process recirculation loop, and the supervisory controller. This integrated arrangement enables the supervisory controller to intelligently orchestrate the operation of all subsystems, delivering precise temperature regulation of the disinfection fluid while optimizing energy efficiency and system performance. In combination, these features enable the plant to respond 5 HK 30137919 A 6 differently to ambient heat ingress and to process disturbance without driving the chiller into unstable operation. Fig. 3 shows an embodiment of a method for regulating the temperature of the disinfection fluid, complementary to the aforementioned system. The method 300 comprises step 310 of storing the disinfection fluid in a storage tank. The disinfection fluid is periodically withdrawn from the tank for use in the disinfection process. During storage, the method 300 regulates the temperature of the disinfection fluid through two complementary steps to maintain it within a preferred range of around 15°C to 20°C. In step 320, the disinfection fluid is circulated from the storage tank through a heat exchanger, where heat is transferred to a cooling medium, thereby lowering the fluid temperature before it is returned to the storage tank. Simultaneously or alternatively, in step 330, a chilled fluid is circulated along a chilled fluid flow path that is thermally coupled to the outer surface of the storage tank. This chilled fluid acts as a heat sink, dissipating heat from the stored disinfection fluid. The flow rate of the chilled fluid is dynamically adjusted based on the detected temperature of the disinfection fluid and / or other environmental parameters. In an embodiment, a supervisory controller (i.e. a flow regulating unit) is configured to continuously, or at predetermined time intervals, acquire process measurements, including the temperature of the disinfection fluid inside the storage tank, flow rates and conditions in the jacket branch and the process heat-exchanger branch, the status of the recirculation loop, and key variables of the chilled fluid. The controller also acquires ambient and environmental measurements, such as ambient air temperature and, optionally, relative humidity, rainfall status, wind speed, solar radiation, and the surface temperature of the storage tank. Based on these inputs, the supervisory controller determines the current operational state of the system and classifies it as one of several modes, including refill mode, delivery mode, idle mode, disturbance recovery mode, or protected degraded operation mode. It further evaluates both the weather-related cooling load and the process-related cooling load, and accordingly determines the optimal allocation of cooling duty between the tank cooling jacket and the process heat exchanger. The controller then issues coordinated control commands to the variable-speed process recirculation pump, the branch valves (or equivalent flow-regulating devices), and the chilled-fluid supply unit. Throughout the operation, it enforces equipment- protection constraints, including minimum run time, minimum off time, minimum chiller-side flow rate, and sensor plausibility checks, while ensuring smooth and stable control mode transitions without chattering. In operation, the method of the present invention links predefined state logic to branch-level actuation to achieve optimal temperature control of the disinfection fluid. In an embodiment, the method comprises acquiring the temperature of the disinfection fluid stored in the storage tank by a temperature sensor, either continuously or at a predetermined time interval, and upon detecting that the temperature exceeds a predetermined threshold value, automatically increasing the circulation speed of the disinfection fluid through the heat exchanger and / or the chilled fluid through the chilled fluid flow path, so as to maintain the temperature of the disinfection fluid within a predetermined range. During refill of the storage tank, the supervisory controller increases the relative cooling contribution of the process-side heat exchanger so as to rapidly remove the thermal disturbance introduced by the incoming warm disinfection fluid, while the tank cooling jacket continues to suppress heat ingress through the vessel walls. 6 HK 30137919 A 7 During idle operation under high ambient thermal load, the controller allocates more cooling duty to the tank cooling jacket, as the dominant heat load then comes from boundary heat ingress through the tank surface. In contrast, during low-load conditions, the controller widens the cooling temperature band and utilizes the storage tank as a thermal buffer. This strategy helps minimize short-cycling of the compressors and improves overall energy efficiency. When sudden rainfall or rapid ambient cooling occurs, the controller proactively reduces the demand on the pumps and valves to prevent overcooling of the disinfection fluid. In the event of abnormal condenser-side conditions or equipment faults, the system transitions into a protected degraded mode, prioritizing stable and safe operation over maximum cooling performance. The supervisory method according to the present invention is deterministic in the engineering sense that actuator commands follow predefined process states, defined load interpretations, bounded transition rules, and explicit equipment- protection overrides. An illustrative embodiment is a sodium hypochlorite solution storage and temperature regulation system installed at the Ma On Shan (Hong Kong) Water Treatment Works. In this arrangement, chilled water generated by a dual-compressor air-cooled chiller is supplied to both the tank cooling jacket branch and the process heat-exchanger branch. The process recirculation loop includes at least one variable- speed recirculation pump to circulate the sodium hypochlorite solution and provide responsive temperature control. The storage tank has a capacity of 20,000 litres. In this embodiment, the two cooling branches perform distinct and complementary roles. Under steady hot-weather conditions, the jacket branch handles the majority of the background thermal load resulting from heat ingress through the tank walls. During tank refill or other short-duration thermal disturbances, the process heat-exchanger branch assumes a larger share of the cooling duty, thereby enabling more direct and rapid removal of the temperature rise caused by the incoming warm disinfection fluid. This selective allocation of cooling duty between the two branches reduces the need to force the entire tank contents to respond through a single cooling path. Detailed performance data for four operating examples are presented in the table of Fig. 4. These examples are as follows: Example 1 Baseline Summer Day – Typical daytime summer operation under clear sky and stable ambient conditions. The baseline summer day is based on the metal-roof and chain-link-fence installation with a direct solar load of 28.11 kW and moderate retained structural heat under a semi-open shaded environment. For this scenario, a control target of 19.0°C is adopted, or in an embodiment, within a range of about 18.5°C to 20.0°C. To achieve better efficiency, the sodium hypochlorite solution temperature may be controlled below 20°C where justified, and the control strategy also considers cheaper electricity periods under the bulk tariff for scheduling additional pre-cooling or thermal buffering. The chiller operates under steady part-load conditions at approximately 50% capacity with only the lead compressor running. All values are based on a 20,000 L tank capacity. Example 2 7 HK 30137919 A 8 Aggressive Night-Time Tariff Pre-Cooling – Off-peak lower-temperature pull- down with next-day thermal buffering. This example represents the preferred tariff-leveraging strategy. It assumes negligible direct solar load but persistent retained structural heat and limited ventilation under the semi-open shaded environment. A lower control target of 17.0°C, or in an embodiment within a range of about 16.0°C to 17.5°C, is adopted to shift the most aggressive cooling duty into the off-peak night-time window. This approach captures lower CLP bulk-tariff electricity rates while creating valuable thermal buffering capacity in the tank inventory for the following day. The chiller operates at full load with both compressors running, while the variable-speed recirculation pump remains within the protected supervisory band of 38–50 Hz. All values are based on a 20,000 L tank capacity. Example 3 Rapid Refill Event – Summer day condition based on Example 1 with 30% tank inventory refilled to 100% within one hour using 25°C solution. This rapid refill event of the disinfection fluid is evaluated under the same summer ambient conditions as Example 1, including a direct solar load of 28.11 kW. A tighter control target of 18.0°C is adopted, or in an embodiment within a range of about 17.5°C to 18.5°C, to promptly recover the product temperature after the introduction of warm incoming fluid. The tank inventory increases from 30% to 100% (i.e. more than 50%) within one hour using 25°C sodium hypochlorite solution. The refill requires an estimated sensible cooling duty of 105.8 kW. Both compressors operate at near-full load to handle the high transient demand. Example 4 Delivery Event – Summer day condition based on Example 1 with tank level reduced from 100% to 30% within four hours. This delivery event is evaluated under the same summer ambient conditions as Example 1. A control target of 19.0°C is adopted. The system may control the solution temperature below 20°C where justified and take advantage of lower CLP tariff periods for pre-cooling. During this event, the tank inventory decreases from 100% to 30% within four hours, corresponding to a total withdrawal of approximately 14,000 litres at an average rate of 3,500 L / h. Unlike refill, delivery does not introduce warm fluid and results in lighter chiller loading, allowing intermittent operation of the lead compressor. Embodiments of the present invention provide a system in which a shared chiller side, a tank cooling jacket branch, a process heat-exchanger branch, a variable- speed process recirculation loop, and deterministic supervisory control are coordinated so that ambient heat ingress and process disturbance are handled through different cooling paths while solution temperature and chiller operation remain within protected operating limits. The invention has been given by way of example only, and various other modifications of and / or alterations to the described embodiment may be made by persons skilled in the art without departing from the scope of the invention as specified in the appended claims. 8 HK 30137919 A CLAIMS 1. A system for regulating temperature of a disinfection fluid for water treatment, comprising: a storage tank configured to hold the disinfection fluid; a heat exchanger in fluid communication with the storage tank, and configured to cool the disinfection fluid as the disinfection fluid passes through the heat exchanger; wherein the system further comprises a chilled fluid flow path thermally coupled to an outer surface of the storage tank, enabling a chilled fluid flows along the outer surface of the storage tank and dissipates heat from the disinfection fluid stored therein. 2. The system as claimed in claim 1, further comprising a chilled-fluid generation unit configured to supply the chilled fluid to both the heat exchanger and along the chilled fluid flow path. 3. The system as claimed in claim 1 or claim 2, comprising a first circulation loop in which the disinfection fluid flows through at least the storage tank and the heat exchanger, and a second circulation loop in which the chilled fluid flows through at least the heat exchanger and the chilled fluid path. 4. The system as claimed in claim 3, wherein each of the first and the second circulation loops comprises one or more flow regulating means configured for varying a flow rate of the fluid within respective circulation path. 5. The system as claimed in claim 4, wherein the one or more flow regulating means is selected from the group comprising a circulation pump, a flow valve, a flow restrictor, and a combination thereof. 6. The system as claimed in claim 4 or claim 5, further comprising a flow regulating unit to control and vary the flow rate of at least one of the disinfection fluid and the chilled fluid, based at least in part on parameters measured by one or more sensors deployed in the system. 7. The system as claimed in claim 6, wherein the one or more sensors comprise a first group of sensors configured to collect flow parameters of at least one of the disinfection fluid and the chilled fluid, the first group of sensors being selected from the group comprising a temperature sensor, a flow meter and a combination thereof. 8. The system as claimed in claim 7, wherein the one or more sensors comprise a second group of sensors configured to collect ambient data externally of the first circulation loop and the second circulation loop. 9. The system as claimed in claim 8, wherein the second group of sensors is selected from the group consisting of a wind sensor, a humidity sensor, a rainfall detector, a solar exposure detector, and combinations thereof. 10. The system as claimed in any one of claims 6 to 9, wherein at least one of the sensors is configured to collect data at a predetermined time interval. 11. The system as claimed in any one of claims 1 to 10, wherein the chilled fluid flow path comprises a pipe wounded around the outer surface of the storage tank. 12. The system as claimed in any one of claims 1 to 11, wherein the disinfection fluid comprises sodium hypochlorite. 9 1 HK 30137919 A 10 2 13. A method for regulating temperature of a disinfection fluid for water treatment, comprising steps of: storing the disinfection fluid in a storage tank, and circulating the disinfection fluid through a heat exchanger; wherein the temperature of the disinfection fluid stored within the storage tank is further regulated by flowing a chilled fluid along a chilled fluid flow path that is thermally coupled to the storage tank, thereby dissipating heat from the disinfection fluid stored therein. 14. The method as claimed in claim 13, further comprising passing the chilled fluid through the heat exchanger to regulate the temperature of the heat exchanger. 15. The method as claimed in claim 13 or claim 14, comprising acquiring one or more fluid parameters of at least one of the disinfection fluid and the chilled fluid to determine regulation of flow thereof, wherein the one or more fluid parameters are selected from the group comprising temperature, flow rate, and a combination thereof. 16. The method as claimed in any one of claims 13 to 15, comprising acquiring one or more ambient parameters of an external environment to determine regulation of flow of at least one of the chilled fluid and the disinfection fluid, wherein the one or more ambient parameters are selected from the group comprising ambient temperature, humidity, rainfall, wind condition, solar exposure, and a combination thereof. 17. The method as claimed in claim 15 or claim 16, further comprising: acquiring the temperature of the disinfection fluid stored in the storage tank; and upon detecting that the temperature of the disinfection fluid exceeds a predetermined threshold value, increasing the circulation speed of at least one of the disinfection fluid through the heat exchanger and the chilled fluid through the chilled fluid flow path, to maintain the temperature of the disinfection fluid within a predetermined range. 18. The method as claimed in claim 17, wherein the temperature of the disinfection fluid is maintained within a range of about 18.5°C to 20.0°C during daytime operation when solar load is present. 19. The method as claimed in claim 17 or claim 18, wherein the temperature of the disinfection fluid is maintained within a range of about 16.0°C to 17.5°C during night- time operation in the absence of solar load. 20. The method as claimed in any one of claims 17 to 19, wherein during a refill operation in which a volume of the disinfection fluid in the storage tank increases by more than 50% within one hour, the temperature of the disinfection fluid is maintained within a range of about 17.5°C to 18.5°C. HK 30137919 A Fig. 1 100 110120 130 140 1 HK 30137919 A Fig. 2 200 210 240 220 230 2 HK 30137919 A Fig. 3 Storing the disinfection fluid in a storage tank. Circulating the disinfection fluid through a heat exchanger. Flowing a chilled fluid along a chilled fluid flow path that is thermally coupled to the storage tank. 300 310 320 330 3 HK 30137919 A Example 1 Example 2 Example 3 Example 4 Scenario Classification Idle Idle Refill Delivery Outdoor Air Temp - Normal (°C) 32 32 32 32 Outdoor Air Temp During Event (°C) 34 36 34 34 Outdoor Air Temperature Change, ΔT (°C) +2 +4 +2 +2 Solar Load Basis (kW) 28.1 0 28.1 28.1 Retained Structural Heat Influence (kW) 8 18 8 8 Tank Volume (L) 20000 20000 20000 20000 Target / Control Solution Temperature (°C) 19 17 18 19 Transfer / Incoming Solution Temperature (°C) - - 25 - Transfer Duration (hr) - - 1 4 Chiller Compressor Loading / ON-OFF State 50% / Lead compressor ON 100% / Both compressors ON 100% / Both compressors ON 0%-50% / Intermittent lead compressor ON Chiller Water Entering Temperature (°C) 12.5 12 14.5 12 Chiller Water Leaving Temperature (°C) 7.5 7 9 7 Chiller Water Delta T, ΔT (°C) -5 -5 -5.5 -5 Tank-to-Heat-Exchanger Water Entering Temperature (°C) 18.8 17.4 25 18.4 Tank-to-Heat-Exchanger Water Leaving Temperature (°C) 16.3 14.9 20 15.9 Tank-Side Heat Exchanger Delta T, ΔT (°C) -2.5 -2.5 -5 -2.5 Heat Exchanger Effectiveness (%) 73 71 58 74 Approx. Cooling Load Change (%) 16 28 58 10 Chiller Water Side Pump / VSD Frequency (Hz) 44 50 50 40 Tank Side Pump / VSD Frequency (Hz) 41 48 49 38 Fig. 4 4 HK 30137919 A