Method and system for recovering heat in distillation processes

Abstract

A system suitable for recovering energy during an alcohol distillation process, comprising at least one still, 1, at least one reboiler configured to heat distillation fluid in the at least one still,

Description

The present invention relates to distillation, and in particular, relates to a method and system for recovering energy during an alcohol distillation process. Aspects of the invention relate to controlling energy recovery from a pot still. Background to the Invention During alcohol distillation a large amount of energy is reguired to heat the pot still to create distillate vapours. The vapours produced rise up the inside of the pot still and partially condense on the cooler copper walls of the still. Uncondensed vapours rise further and usually travel over the still swan neck. Typically, the vapours travel along a lyne-arm and are then condensed in a variety of condensers, such as worm tub or shell and tube condenser systems. Cooling water is passed through the condensers from a cooling circuit that removes heat to the air via cooling towers or cooling ponds. Heat losses from the pot still occur as radiant and convective heat losses from the walls of the still. Historically pot stills were heated by “direct fire”, this would typically mean wood, coal or gas flames contact a copper still bottom directly. In more modern times most pot stills are now heated using steam from a steam boiler. However, a large amount of energy is reguired to heat the pot stills. With temperatures rising due to global warming and rainfall patterns being affected, the air temperature for cooling in towers or ponds is becoming more of a concern. Low rainfall or high air temperatures can stop production. The process may also have evaporative water losses increasing demand on the local environment for top up water. Traditional pot stills have been used for centuries to distil spirits such as ethanol. However, there has been a need for improved processes that offer better environmental and energy efficiency benefits. Summary of the Invention It is an object of an aspect of the present invention to obviate or at least mitigate the foregoing disadvantages of prior art alcohol distillation processes. It is another object of an aspect of the present invention to provide a system and method for recovering and / or repurposing low-grade latent, convective and / or radiative heat losses from pot stills. It is a further object of an aspect of the present invention to recover heat at higher temperatures from the condensation of distillates, so that the efficiency of equipment such as heat pumps can be improved. According to a first aspect of the invention there is provided a heat recovery system for an ethanol distillation process comprising: at least one still; at least one reboiler configured to heat a distillation fluid in the at least one still; at least one condenser configured to cool a fluid in the at least one still; at least one heat pump; wherein the at least one heat pump is configured to heat fluids recovered from the at least one condenser and / or the at least one reboiler. The at least one heat pump may be connected to at least a part or component of the at least one reboiler and / or to at least a part or component of the at least one condenser. The at least one heat pump may be in fluid communication with at least a part or component of the at least one reboiler and / or to at least a part or component of the at least one condenser. The at least one heat pump may be a high temperature heat pump. The at least one heat pump may be a very high temperature heat pump. The at least one heat pump may be a high temperature heat pump or a very high temperature heat pump configured to transfer thermal energy recovered during the distillation process to maintain hot water temperatures in at least one hot water tank. The at least one heat pump may be a heat exchanger. The at least one heat pump may be configured to heat the fluid to a temperature of between 50°C to 200°C. The very high temperature heat pump may be configured to allow a heat transfer fluid to reach a temperature of between 50°C to 200°C. The very high temperature heat pump may be configured to allow a heat transfer fluid to reach a temperature of between 100°C to 200°C. The system may comprise a condenser system. The system may comprise a condenser system comprising at least one condenser. The system may comprise one or more condensers. The at least one condenser may comprise a reflux jacket. The condenser system may comprise a reflux jacket and at least one further condenser. The condenser system may comprise a reflux jacket and a split condenser. The at least one condenser may comprise a collar condenser. The system may comprise a first condenser configured to cool a fluid in the neck portion or a downstream portion of the neck portion to within a first temperature range. The system may comprise a second condenser configured to cool a fluid within a second temperature range. The first condenser may be configured to cool a fluid from a temperature of approximately 100°C to approximately 70°C. The second condenser may be configured to cool a fluid from a temperature of approximately 70°C to less than 25°C. The at least one condenser may be designed such that heat transfer may occur at controlled flow rates. This may cause the cooling liquid to exit the condenser and / or reboiler at higher temperatures which may provide a higher coefficient of performance in the very high temperature heat pump. The at least one heat pump may be configured to heat a heat transfer fluid recovered from the at least one condenser and / or the at least one reboiler. The at least one condenser may be configured to heat a heat transfer fluid (cooling fluid) to a higher temperature in the range of 60°C to 90°C such that the at least one heat pump efficiency may be improved. The at least one condenser may be configured to heat the heat transfer fluid (cooling fluid) to a higher temperature in the range of 60°C to 90°C wherein more heat may be recovered from the at least one or more condensers. The at least one condenser may be configured to transfer heat to a heat transfer fluid (cooling fluid) to a higher temperature in the range of 60°C to 90°C. The at least one condenser may be configured to transfer heat to a heat transfer fluid (cooling fluid) to a higher temperature in the range of 60°C to 90°C such that the at least one heat pump efficiency may be improved and wherein more heat may be recovered from the at least one or more condensers. The first condenser may be an upper condenser. The second condenser may be a lower condenser. The system may comprise an upper condenser configured to cool a fluid to within a first temperature range. The system may comprise a lower condenser configured to cool a fluid within a second temperature range. The system may comprise at least one split condenser. The at least one split condenser may comprise at least one vertical plate and / or at least one horizontal baffle. The at least one split condenser may comprise vertical plates and / or horizontal baffles providing distinct temperature- regulated condensation. The vertical plates and / or horizontal baffles may be configured to enable temperature-regulated recovery at multiple stages. This may also enable optimisation of the heat pump performance via increased inlet temperature. The at least one split condenser may comprise vertical and / or horizontal baffles to allow cooling media to achieve multiple temperature ranges. The at least one split condenser may comprise vertical and / or horizontal baffles to allow cooling media from one or more storage tanks to achieve a third temperature range. The third temperature range may be 60°C to 100°C. The upper condenser may be configured to cool a fluid in the neck portion or a downstream portion of the neck portion from a temperature of approximately 100°C to approximately 70°C. The lower condenser may be configured to cool a fluid in the neck portion or a downstream portion of the neck portion from a temperature of approximately 70°C to less than 25°C. The system may comprise a condenser and / or a reflux jacket surrounding or at least partially surrounding the neck portion of the at least one still. The system may comprise a third condenser and / or a reflux jacket surrounding or at least partially surrounding the neck portion of the at least one still. The reflux jacket may be a condenser or a condenser jacket. The reflux jacket may be configured to cool fluid and / or recover heat from at least a portion of still neck. The reflux jacket may be configured to control a temperature of the fluid passing through the neck such that the spirit reflux rate is comparable to a conventional pot still with radiative and convective heat losses. The cooling fluid around neck may be a higher temperature due to concurrent flow. The cooling fluid circulating at the neck may be at a higher temperature and more efficiently used in VHTHP. The reflux jacket may be configured to transfer heat from the vapours which are at the top of the still. This may be due to cooling fluid circulating concurrently with the still vapour flow. This may give a maximum temperature differential for effective heat transfer. The system may comprise at least one reboiler or reboiler section. The system may comprise at least one reboiler. The system may comprise at least one reboiler section. The system may comprise two or more reboilers. The system may comprise at least two reboilers. The system may comprise at least two reboiler sections. The system may comprise a first reboiler configured to heat fluid in at least one still using heat from a heat source such as cascading heat pumps, electric heater and / or gas heater. The system may comprise a first reboiler configured to heat fluid in at least one still using heat from a solar heating system. The solar heating system may be configured to use solar energy to heat fluids. The solar heating system may be configured to use solar energy to heat fluids such as thermal oil, pressurised water at 115°C at 1.7 bar or thermal salts. The second reboiler may be configured to heat distillation fluid in at least one still using heat from the at least one heat pump. The second reboiler may be configured to heat distillation fluid in at least one still using heat from the at least one heat pump acting as a heat exchanger. The first reboiler may be an upper reboiler. The second reboiler may be a lower reboiler. The at least one reboiler may use a thermosiphon to heat fluid in at least one still. The at least one reboiler may use pumped circulation to heat fluid in at least one still. The at least one reboiler may be a split reboiler. The split reboiler may have upper section and a lower section. Each of the at least one reboiler or reboiler section may be heated by an independent heat source. Each of the upper section and / or lower section may be heated by an independent heat source. The independent heat source may be selected from the group comprising solar buffer, very high temperature heat pump and / or immersion heaters, cascading heat pumps, electric heater and / or gas heater. The system may comprise an upper reboiler configured to heat fluid in at least one still using heat from a heat source such as a heat pump, electric heater and / or gas heater. The system may comprise an upper reboiler configured to heat fluid in at least one still using heat from a solar heating system. The lower reboiler may be configured to heat distillation fluid in at least one still using heat from the at least one heat pump. The lower reboiler may be configured to heat distillation fluid in at least one still using heat from the at least one heat pump acting as a heat exchanger. An outlet from the at least one condenser and / or at least one reboiler may be in fluid communication with an inlet of the at least one heat pump. An outlet from at least one heat pump may be in fluid communication with an inlet in the lower reboiler. The still may be a wash still. The still may be a spirit still. The distillation fluid may be selected from the group comprising wash, mash, wort, beer, wine, any fermented liquid, any liquid containing fermented sugars, any liquid derived from fermented barley, any liquid derived from rye grain, and any liquid that contains a volatile component that can be separated using distillation. According to a second aspect of the invention there is provided method of reducing energy consumption in an ethanol distillation process, the method comprising: providing a heat recovery system comprising at least one still; at least one reboiler configured to heat a distillation fluid in the at least one still; at least one condenser configured to cool a fluid in the at least one still; at least one heat pump; passing fluids from the at least one condenser and / or from the at least one reboiler to the at least one heat pump; heating the fluids in the at least one heat pump and circulating the heated fluids to the at least one reboiler. The at least one heat pump may be connected to at least a part or component of the at least one reboiler and / or to at least a part or component of the at least one condenser. The at least one heat pump may be in fluid communication with at least a part or component of the at least one reboiler and / or to at least a part or component of the at least one condenser. The method may comprise storing heated fluids in at least one hot liquor tank, medium temperature liquor tank or solar buffer tank to be circulated to the at least one reboiler or the at least one condenser. The at least one condenser may be configured to cool vapour in the at least one still and / or downstream of the at least one still. The method may comprise passing a heat transfer fluids from the at least one condenser and / or from the at least one reboiler to the at least one heat pump. The method may comprise heating the fluids in the at least one heat pump and circulating the heated fluids to the at least one reboiler. The heat transfer fluid may be water, steam, oil, glycol or a water and glycol mixture. The method may comprise cooling fluids in at least one heat pump. The method may comprise circulating the cooling fluids to the at least one condenser. The distillation fluid may be heated to temperatures of 115°C to 120°C. The distillation fluid may be heated to temperatures up to 150°C. The distillation fluid may be heated to temperatures up to 200°C. The distillation fluid may be heated to temperatures of at least 100°C. The distillation fluid may be heated to temperatures of at least 150°C. The distillation fluid may be heated to temperatures of at least 200°C. The method may comprise at least one condenser. The method may comprise two condensers. The method may comprise at least two condensers. The method may comprise a split condenser. The system may comprise a condenser system. The at least one condenser may comprise a reflux jacket. The condenser system may comprise a reflux jacket and at least one further condenser. The condenser system may comprise a reflux jacket and a split condenser. The method may comprise cooling a distillation fluid or vapour from a temperature of approximately 100°C to approximately 70°C in a first condenser. The method may comprise cooling a distillation fluid or vapour from a temperature of approximately 70°C to less than 25°C in a second condenser. The method may comprise cooling water temperatures of approximately 60°C to 85°C to be more efficient when circulated to the heat pump. The method may comprise heating distillation fluid in at least one still using a first upper reboiler heated from a heat source such as electric heater, pressurised hot water, gas heater and / or solar heated oil and / or steam. The method may comprise heating distillation fluid in at least one still using a second lower reboiler heated from heated fluid from the at least one heat pump. The method may comprise recovering heat from the neck portion of the at least one still by circulating a heat transfer fluid through a reflux jacket surrounding or at least partially surrounding the neck portion of the at least one still. The heat transfer fluid may be to or from the attached top condenser or bottom condenser. The heat transfer fluid may be water. The method may comprise recovering waste heat from a heated distillation fluid, heated still and / or at least one condenser. The method may comprise heating the still and / or a hot liquor tank using the recovered waste heat. Embodiments of the second aspect of the invention may include one or more features of the first aspect of the invention or its embodiments, or vice versa. According to a third aspect of the invention, there is provided method for reducing energy consumption in an ethanol production process, the method comprising: recovering waste heat from a heated distillation fluid, heated still and / or at least one condenser; and heating the still and / or a hot liquor tank using the recovered waste heat. The method may comprise passing the recovered waste heat to a heat pump. The method may comprise heating a fluid to up to 200°C using the heat pump and recovered waste heat. The ethanol production process may be a whisky production process, a tequila production process, a vodka production process, a gin production process, a rum production process, a brandy production process or any production process that may include distillation using one or more stills. The heat pump may be a high temperature heat pump. The heat pump may be a very high temperature heat pump. The heat pump may be cascading heat pumps. The method may comprise converting the recovered waste heat to steam. The steam may be at temperatures of 120°C or above. Embodiments of the third aspect of the invention may include one or more features of the first or second aspects of the invention or its embodiments, or vice versa. According to a fourth aspect of the invention there is provided a solar energy utilisation system for ethanol production, comprising: providing a solar energy system configured to convert solar energy to heat a fluid, storing the heated fluid in the least one thermal storage system; heating at least one distillation still using heated fluid from at least one thermal storage system. The heated fluid may be selected from the group comprising water, pressurised water, pressurised water from a tank at 1.7 bar, steam, hot oil and / or a water and glycol mixture. The thermal storage system may comprise discrete high-heat capacity concrete elements with pipes. The pipes may be steel pipes. The pipe may be inside the concrete elements. The thermal storage system may be capable of storing energy at temperatures up to 400°C. The thermal storage system may have a 2% loss in temperature in 24 hours. The method may comprise adjusting an annual whisky production rate to align with solar energy availability. The method may comprise optimising energy utilisation and / or whisky production. The method may comprise heating at least one reboiler using the heated fluid from the solar storage system. The method may comprise heating at least one reboiler using the heated fluid from the solar storage system stored from a previous day, an earlier point in time, or an earlier point in time. Embodiments of the fourth aspect of the invention may include one or more features of the first to third aspects of the invention or their embodiments, or vice versa. According to a fifth aspect of the invention there is provided a method of heat recovery in an ethanol production process, the method comprising: providing a heat recovery system comprising: at least one still; at least one condenser on a neck portion of the at least one still; passing the preheated water through the at least one condenser; passing the heated water from the at least one condenser to at least one hot water storage tank. The at least one condenser may be located on or at a downstream portion of the neck portion of the at least one still. The method may comprise pumping water through the at least one condenser to preheat the water. The at least one condenser may be a collar condenser. The hot water storage tank may be a hot liquor storage tank. The method may comprise passing water from the at least one condenser, collar condenser and / or from at least one reboiler to at least one heat pump. The method may comprise heating the fluids in the at least one heat pump and / or circulating the heated fluids to the at least one reboiler. The ethanol production process may be a whisky production process, a tequila production process, a vodka production process, a gin production process, a rum production process, a brandy production process or any production process that may include distillation using one or more stills. Embodiments of the fifth aspect of the invention may include one or more features of the first to fourth aspects of the invention or their embodiments, or vice versa. According to a sixth aspect of the invention, there is provided a heat recovery system for an ethanol distillation process comprising: at least one still; at least one reboiler configured to heat distillation fluid in the at least one still; at least one condenser; at least one heat pump; wherein the at least one heat pump is configured to heat fluids recovered from the at least one condenser and / or the at least one reboiler; wherein the at least one condenser comprises a reflux jacket. The at least one heat pump may be a high temperature heat pump or a very high temperature heat pump. The at least one condenser may be configured to cool a fluid in a neck portion and / or a downstream portion of the neck portion of the at least one still. The at least one condenser may be configured to cool and recover heat from at least a neck portion of the still. The reflux jacket and / or the at least one condenser may be configured to cool and / or recover heat from at least a neck portion of the still. The at least one condenser may further comprise a first condenser configured to cool a fluid to a temperature within a first temperature range and a second condenser configured to cool a fluid in the neck portion to a temperature within a second temperature range. The at least one condenser may be configured to transfer heat to a heat transfer fluid to a temperature in the range of 60°C to 90°C. The first condenser may be configured to cool a fluid from a temperature of approximately 100°C to approximately 70°C and / or the second condenser may be configured to cool a fluid from a temperature of approximately 70°C to less than 25°C. The at least one condenser may comprise a split condenser with vertical plates and / or horizontal baffles. The at least one condenser may be a split condenser with vertical plates and / or horizontal baffles that allow at least two input streams and at least two output streams for the cooling fluid to be heated from at least two different starting temperatures. A first section of the split condenser may be configured to cool a fluid from a temperature of approximately 100°C to approximately 70°C and / or a second section of the split condenser may be configured to cool a fluid from a temperature of approximately 70°C to around 25°C or less. The reflux jacket may surround or at least partially surround the neck portion of the at least one still. The reflux jacket and / or the at least one condenser may be configured to control a temperature of vapour and / or liquid passing through the neck of the still to control or adjust a flavour of the distillate. The reflux jacket may be configured to recover heat from the neck portion of the still and precisely manages reflux rates to influence distillate flavour. The reflux jacket surrounding the still neck may be configured to recover heat and / or control distillate flavour through managed reflux temperature. The reflux jacket and / or the at least one condenser may be configured to transfer heat from vapours at a top of the still. The system may comprise at least two reboiler or reboiler sections. A first reboiler may be configured to heat fluid in at least one still using heat from at least one heat source such as a very high temperature heat pump, electric heater, and / or gas heater with the heat medium being pressurised water and / or steam. The first reboiler may be configured to heat fluid in at least one still using heat from a solar heating system. The solar heating system may be configured to use solar energy to heat fluids. The second reboiler may be configured to heat a distillation fluid in the least one still using heat from at least one heat pump or very high temperature heat pump. The system may comprise an outlet from the at least one condenser and / or at least one reboiler in fluid communication with an inlet of the at least one heat pump. The system may comprise an outlet from at least one heat pump in fluid communication with an inlet of at least one reboiler. The still may be a wash still or a spirit still. Embodiments of the sixth aspect of the invention may include one or more features of the first to fifth aspects of the invention or their embodiments, or vice versa. According to a seventh aspect of the invention, there is provided a method of reducing energy consumption in an ethanol distillation process, the method comprising: providing a heat recovery system comprising: at least one still; at least one reboiler configured to heat a distillation fluid in the at least one still; at least one condenser; at least one heat pump; wherein the at least one condenser comprises a reflux jacket; passing fluids from the at least one condenser and / or from the at least one reboiler to the at least one heat pump; heating the fluids in the at least one heat pump and circulating the heated fluids to the at least one reboiler. The method may comprise heating the fluid to temperatures up to 200°C. The system may comprise a first condenser, wherein the method may comprise cooling a fluid in the neck portion and / or a downstream portion of the neck portion from a temperature of approximately 100°C to approximately 70°C in the first condenser. The system may comprise a second condenser, wherein the method may comprise cooling a fluid in the neck portion and / or a downstream portion of the neck portion from a temperature of approximately 70°C to less than 25°C in the second condenser. The method may comprise heating distillation fluid in at least one still using a first reboiler heated from a heat source such as an electric heater, heat pump, very high temperature heat pump, pressurised water, gas heater, solar heated oil and / or steam. The method may comprise heating distillation fluid in at least one still using a second reboiler heated from heated fluid from the at least one heat pump, electric heater, very high temperature heat pump, pressurised water, gas heater, solar heated oil and / or steam. The method may comprise recovering heat from the neck portion of the at least one still by circulating cold fluid through the reflux jacket surrounding or at least partially surrounding the neck portion of the at least one still. The method may comprise controlling a temperature of the distillation fluid passing through the neck of the at least one still to control and / or adjust a flavour of the distillation fluid. The method may comprise controlling a temperature of a cooling fluid by adjusting flow to match required reflux rates. Embodiments of the seventh aspect of the invention may include one or more features of the first to sixth aspects of the invention or their embodiments, or vice versa. According to an eighth aspect of the invention, there is provided a heat recovery system for an ethanol distillation process comprising: at least one still; at least one reboiler configured to heat distillation fluid in the at least one still; a condenser system; at least one heat pump; wherein the at least one heat pump is configured to heat fluids recovered from the condenser system and / or the at least one reboiler; wherein the condenser system comprises a reflux jacket. The condenser system may comprise at least one condenser. The condenser system may comprise two condensers. The condenser system may comprise at least two condensers. The condenser system may comprise a split condenser. The at least one condenser may comprise a reflux jacket. The condenser system may comprise a reflux jacket and at least one further condenser. The at least one condenser may further comprise a first condenser configured to cool a fluid to a temperature within a first temperature range and a second condenser configured to cool a fluid in the neck portion to a temperature within a second temperature range. The at least one condenser may be configured to transfer heat to a heat transfer fluid to a temperature in the range of 60°C to 90°C. The first condenser may be configured to cool a fluid from a temperature of approximately 100°C to approximately 70°C and / or the second condenser may be configured to cool a fluid from a temperature of approximately 70°C to less than 25°C. The at least one condenser may be a split condenser with at least one vertical plates and / or at least one horizontal baffles. The at least one condenser may be a split condenser with two or more vertical plates and / or two or more horizontal baffles. The condenser system may comprise a reflux jacket and at least one condenser. The condenser system may comprise a reflux jacket and a split condenser. The at least one condenser may be configured to cool a fluid in a neck portion and / or a downstream portion of the neck portion of the at least one still. The at least one condenser may be configured to cool and recover heat from at least a neck portion of the still. The reflux jacket and / or the at least one condenser may be configured to cool and / or recover heat from at least a neck portion of the still. Embodiments of the eighth aspect of the invention may include one or more features of the first to seventh aspects of the invention or their embodiments, or vice versa. According to a ninth aspect of the invention, there is provided a heat recovery system for an ethanol distillation process comprising: at least one still; at least one reboiler configured to heat distillation fluid in the at least one still; at least one reflux jacket condenser configured to cool a fluid in a neck portion; at least one heat pump; wherein the at least one heat pump is configured to heat fluids recovered from the at least one condenser and / or the at least one reboiler. Embodiments of the ninth aspect of the invention may include one or more features of the first to eighth aspects of the invention or their embodiments, or vice versa. According to a tenth aspect of the invention, there is provided an ethanol distillation plant comprising at least one heat recovery system according to any of the first, fourth, sixth, eighth or ninth aspect of the invention. Embodiments of the tenth aspect of the invention may include one or more features of the first to ninth aspects of the invention or their embodiments, or vice versa. Brief description of the drawings There will now be described, by way of example only, various embodiments of the invention with reference to the drawings, of which: Figure 1 is a schematic drawing of an ethanol production process according to in accordance with an aspect of the invention; Figure 2 is an enlarged view of pot still system of ethanol production system in accordance with an aspect of the invention; Figure 3 is an enlarged view of pot still system of ethanol production system with an alternative reflux jacket design in accordance with an aspect of the invention; Figure 4 is an enlarged view of pot still system of ethanol production system with an alternative condenser design in accordance with an aspect of the invention; Figure 5 is a schematic drawing of flow paths through a heat recovery system of an ethanol production process in accordance with an aspect of the invention. Detailed description of preferred embodiments Figure 1 is an overview of a heat recovery system 100 for an ethanol distillation process. The system 100 comprises a still 1, a mash tun 12, very high temperature heat pumps (VHTHP) 2, 3, hot fluid storage 4, 5, 6,13, a top condenser 23, a bottom condenser 24, reflux condenser 9, heat exchanger 10, reboilers 21, 22 and cold-water tank 14. The system 100 includes multiple components, each contributing to the overall efficiency and functionality of the heat transfer process. The connections between the above components are shown in Figure 1 using lines and arrows. Figure 2 shows an enlarged view of the pot still 1 and how it is connected to components of the heat recovery system 100. The drawing delineates the interconnected nature of these components, demonstrating a complex yet efficient system for managing thermal energy through the use of advanced heat pump technology. Figure 2 is an enlarged view of pot still 1 for ethanol production. The pot still 1 is a distillation apparatus designed for the separation of ethanol from a wash mixture. The pot still is heated by a reboiler 21,22 having a top section 22 and a bottom section 21. In this example the pot still is made from copper. As shown in Figures 1 and 2, the system comprises a pot still 1, a reflux jacket 20, a split condenser 23, 24 and a split reboiler 21,22. In this example the pot still is a wash still 1. However, it will be appreciated the pot still may be a spirit still. During the distillation process wash is heated in the still. In this example a split reboiler is employed with an upper reboiler section 22 and a lower reboiler section 21. However, it will be appreciated that there may only be one reboiler section. The upper reboiler creates a convection current which heats the still body 1 and the wash contained in the still. The upper reboiler (R2) 22 starts the process as a supply of hot oil, steam, pressurised water at 1.7 bar or alternative heat sources 43 are provided to the upper reboiler 22 via flow line 31 which then circulates back to a hot liquor tank via flow line 33. The lower reboiler section (R1) 21 is supplied with hot fluids via flow line 32 from a very high temperature heat pump 2,3 which then circulates within the lower reboiler section (R1) 21 and back to the very high temperature heat pump 2,3 via flow line 34. The convection current generated by the split reboiler 21,22 heats the wash still 1 and the wash in the still, initiating the production of ethanol vapours. In this example the heated fluid provided to the lower reboiler along flow line 32 from a very high temperature heat pump 2, 3 via a hot heat store 4 raises the temperature of heated fluids. The heated fluid provided to the lower reboiler is stored in hot fluid storage tanks 4,5. In this example heat is maintained by immersion heaters 15,16,17,18,19 powered by solar energy 60. It will be appreciated that the heated fluid provided to the upper reboiler may be provided by alternative sources 43 such as electric heater, heat pump, hot liquor tank, medium temperature liquor tank, pressurised water, gas heater, solar heated oil and / or steam. In this example, heated fluid from the upper reboiler 22 enters the still via flow line 35 and circulates back to the lower reboiler 21 via flow line 36. As the wash is heated alcohol vapours are created which rises through the neck section 25 of the still. Ethanol vapours rise up the pot still neck 25 and are partially cooled by the reflux jacket 20, this is due to cooling fluid circulating concurrently with the still vapour flow. In this example the cooling fluid (heat transfer fluid) is water. This gives the maximum temperature differential for effective heat transfer. Allowing for the progressive condensation and re-evaporation of the ethanol vapours. As the hot vapour contacts the cooler surfaces, partial condensation occurs, causing some of the vapour to revert to liquid form and flow back down into the still 1. This process, known as reflux, increases the purity of the ethanol by allowing multiple distillation cycles and repeated reaction with the copper still to remove unwanted compounds which may affect the taste of the distillate product. Waste pot ale at the end of the batch is directed to a discharge tank 7 via a heat exchanger 6 via flow line 37. A heat transfer fluid enters the split condenser via flowline 26,27 and which is heated to recover some heat from the process. In this example the heat transfer fluid is water. The ethanol vapours from the top of the pot still 1 enter the split condenser 23,24. The top condenser 23 cools the vapours from 100°C to 70°C, and then the bottom condenser 24 cools them to less than 25°C before directing them to the Low Wines &Feints receiver 38. There are two cooling streams for the split condenser 23, 24, a top cooling stream 26 is provided by a 60°C hot liquor tank 6 via flow line 26, while the secondary cooling stream for the split condenser is supplied via flowline 27 as cold water from the main cold-water tank 14. The split condenser 23, 24 is in fluid communication with the reflux jacket 20 and the heat transfer fluid 30 circulates within the reflux jacket 20 to recover heat from the neck section of the still 20. In this example, the heat transfer fluid flows along flow line 28 from the reflux jacket 20 to a hot liquor tank 4 to then recirculate into the very high temperature heat pump (VHTHP) 2,3 at around 85°C to 90°C. The VHTHP 2,3 utilises low amounts of electric power to further heat recovered low-grade heat from various sources 43 (e.g., condensers, reflux jacket, and still neck) to temperatures of up to 200°C. This unit has a high coefficient of performance that enables the efficient recovery of convective and radiative losses, heat of vaporisation, and latent heat. In this example the heat pump is powered by solar energy via a battery energy storage system (BESS). However, it will be appreciated that alternative means of powering the heat pump may be used. The hot liquor tank 13 receives water (heat transfer fluid) recovered from the reflux condenser and split condenser for storage to then be re-used in the system. This saves otherwise wasted heat. The hot liquor tank will store heated water at temperatures of up to 90°C. A secondary liquor tank 6 will store fluid at 60°C to 90°C. Hot liquor tank 13 may be in fluid communication with medium liquor tank 6 to achieve optimum temperature fluid for VHTHP. In this example, the reflux jacket 20 is wrapped around the neck of the still 25 and serves multiple functions, including cooling the still neck, recovering heat from the process, enhancing the flavour of the final product and receiving fluid from the split condenser 23,24. The reflux jacket recovers heat from the still and dictates the rate of reflux within the still, This may impact the flavour and / or rate of production of the distillate. This may also improve separation efficiency and / or heat utilisation. The heat transfer fluid used for cooling the split condenser 23, 24 flows along flow line 30 to cool the reflux jacket 20 on the neck of the still 25. The heat transfer fluid enters the reflux jacket 20 and into a coil within the jacket. This evenly cools the pot still neck 25 and heat from the neck of the still is transferred to the heat transfer fluid in the reflux jacket recovering heat that is generally lost during this process. Figure 3 is a cross-sectional drawing of an ethanol production system. The system is similar to the system described in Figure 2 and will be understood from the description of Figures 2. However, Figure 3 has an alternative reflux jacket design. Figure 3 shows an alternative option for cooling the still neck 125 causing reflux. In this variation, the reflux jacket 120 has water entering as in Figure 1 from the lower section of the split condenser 130. However, the water enters a vessel at the top of the still neck 130. There is tubing 139 descending within the jacket 120 completely surrounding the still neck 125 for the water to feed into. In this example the reflux jacket is made of copper. It will be appreciated that the jacket could be made of stainless steel, copper, glass, aluminium or any other material that can withstand high temperatures and provide effective heat transfer. In this example the tubing is made of copper. It will be appreciated that the tubing could be made of copper, stainless steel, glass, PTFE or any other material that can withstand high temperatures, provide effective heat transfer and resist chemical reactions. Control loops have sensors that measure temperature around the circumference around the still neck and indicate which tubes the water enters, evenly cooling the internal spirits. The water is then captured at the bottom of the reflux jacket 120 after recovering heat from the distillation process. The now heated water is transferred to a hot liquor tank 4 at around 90°C via flow line 28 as in Figure 2. Figure 4 is a cross-sectional drawing of an ethanol production system. The system is similar to the systems described in Figure 2 and Figure 3 and will be understood from the description of both figures. However, Figure 4 has an alternative condenser design. In this example, the condenser is a split condenser 223, 224 specifically designed to enhance condensation efficiency and improve the quality of the distilled spirit. In this example, the split condenser features a unique configuration with at least one vertical plate and at least one horizontal baffle to optimise heat exchange and condensation rates along with an exit stream that feeds a hot liquor tank 13 at a higher temperature via flow line 30. The vertical plates and / or horizontal baffles may be configured to enable temperature-regulated recovery at multiple stages. This may also enable optimisation of the heat pump performance via increased inlet temperature. In this example, the reflux jacket 220 is fed via flow line 229 by a medium temperature liquor tank 6. The split condenser 223, 224 comprises a cylindrical housing 239 made from high-grade stainless steel or copper, ensuring durability and resistance to corrosion. Within the housing 239, the condenser is divided into two separate chambers 223 and 224 by an internal partition 240. This partition is also constructed from the same high-grade material to maintain consistency and durability. Each chamber 223 and 224 contains one or more vertical plates 241 alongside horizontal baffles 261. In this example the plates 241 and baffles 261 are made from copper, chosen for its excellent thermal conductivity, which facilitates efficient heat transfer and rapid condensation of vapour into liquid. The surfaces of the plates 241 and baffles 261 could be polished to reduce any potential for fouling and to ensure smooth liquid flow. The plates allow various separate multiple flow paths for the cooling medium, allowing a specific range of outlet temperatures at flow lines 230 and 242. The vapour inlet 225 is positioned at the top of the condenser housing 223a, allowing the hot vapour from the distillation column to enter the first chamber 223. The vapour flows downward between the tubes within the first chamber 223, where initial condensation occurs. A baffle 240 connects the lower end of the first chamber 223 to the upper end of the second chamber 224, directing the cooling medium in the separate plated section in the second chamber 224. In the second chamber 224, further condensation occurs as the vapour flows downward in the tubes of the condenser, resulting in the collection of the condensed liquid at the bottom. The condenser shell is designed to circulate at least one coolant fluid, such as water, to recover heat from the vapour and facilitate condensation. The at least one coolant fluid enters the condenser 223, via flow line 226 from the hot liquid tank 6 and flow line 227 from the cold-water tank 14. Flow line 226 flows through the top section of the condenser and exits via flow line 242 at temperatures of between 70°C and 100°C. Flow line 227 flows through the condenser and exits via flow line 230 at temperatures of 70°C and 100°C. This optimises the heat recovery within the system by maximising the temperature of the recovered coolant. The fully condensed liquid (whisky distillate) is collected at the bottom of the second chamber 224 and exits through the condensate outlet 238. The split design of the condenser with vertical plates 241 and horizontal baffles 261 in each chamber optimises the surface area for heat exchange, enhancing condensation efficiency and allows increased coolant temperatures to increase heat pump efficiency. The use of copper plates improves the removal of undesirable sulphur compounds, resulting in a higher-quality condensate. The separate chambers allow for staged condensation, providing better control over the process and resulting in a more refined final product, and maximise process heat recovery at higher temperatures. Figure 5 shows an example of a very high temperature heat pump 2, 3. For clarity only one very high temperature heat pump 2 is shown in Figure 5. It will be appreciated that optional very high temperature heat pump 3 has the same structure and functionality as very high temperature heat pump 3 and will be understood from the description of very high temperature heat pump 2 below. The high temperature heat pump 3 is connected to hot manifolds 44,45 and cold manifolds 46, 47. Figure 5 shows the multiple incoming streams for the very high temperature heat pump including but not limited to hot liquor tank 13 via flow line 48, the split condenser 23, 24 via flow lines 49 and 50, and the split reboiler 21,22 via flow lines 34 and 134. It will be appreciated that hot liquor tank 13 may act as a manifold / buffer tank for incoming streams for the VHTHP. It will be appreciated that the VHTHP may have incoming streams from two ethanol production systems. The very high temperature heat pump 2 comprises a primary compressor unit, a condenser coil, an evaporator coil, an expansion valve, optionally subcoolers and optionally a desuperheater. In this example the heat pump is enclosed in a robust housing made from durable materials capable of withstanding high operational temperatures, and optionally pressurised for ATEX requirements. The very high temperature heat pump is connected to hot manifolds 44, 45 and cold manifolds 46,47 to efficiently distribute heat and collect cold fluid, respectively. The hot manifold 45 is connected to the output side of the condenser coil via an internal heat exchanger via flow line 54, ensuring the distribution of high-temperature fluid. The cold manifold 47 is connected to the input side of the condenser coil via flow line 55, facilitating the collection and recirculation of cooled fluid. The manifolds can be around 15,000 or 20,000 litres each or consist of low-loss headers. The cold manifold 46 supplies cooler fluid to the hot liquor tank 13 or medium temperature tank 6 via flow line 57, where preheated water is stored and maintained at a desired temperature for use in various stages of the distillation process. The tank is equipped with an inlet and an outlet for fluid transfer. The condenser 23, 24 receives cooling fluid from both a cold-water tank 14 and a medium-temperature liquor tank 6. The condenser 23,24 includes an inlet for receiving vapour from the distillation column (still neck) 25 and a condenser outlet 38 for discharging condensed liquid. The condenser 23,24 has exit cooling fluid streams 30,42 at a high temperature of 75°C to 90°C. The split reboiler 21,22 comprises two separate chambers R1 and R2, each containing a series of heating coils. The hot manifold 45 supplies heat to these coils via flow lines 58, 59 facilitating the reboiling of the distillate. Each chamber R1, R2 is equipped with its own heating medium inlet 31, 32 and outlet 33, 34, allowing for staged reboiling and enhanced control over the distillation process. A series of pumps and valves control the flow of fluids between the heat pump 2, hot liquor tank 4, 5, 6, 13, split condenser 7, 8, and split reboiler 21, 22. The cold manifold 47 collects the cooled fluid from R1 and R2, 33, 34 via flow lines 34, 134, then recirculates it through the heat pump via flow line 55. The heat pump 2 utilises the refrigerant cycle, wherein the compressor unit compresses the refrigerant, raising its temperature then hot refrigerant is used via an internal plate heat exchanger to heat the heat transfer fluid (in this example 1.7 bar pressurised water from 105°Cto 115°C). The heat transfer fluid is then directed through the hot manifold 45 to the connected split reboiler 21,22. After transferring heat, the heat transfer fluid flows through the condenser coil, manifold 47 and flow line 55 where it is reheated, thus cooling the fluid before it is recirculated. Heat pump 1 or 2 may also send heat transfer fluid to another heat pump such as the heat pumps are cascaded for further heat pump efficiency. The integration of hot and cold manifolds ensures efficient heat distribution and collection, reducing energy consumption and increases flexibility during transient batch processes. The hot / medium liquor tanks 4, 5, 6,13, split condenser 23, 24, and split reboiler 21,22 may work in tandem to enhance the distillation process, improving the quality of the whisky and maximising high temperature heat recovery. The staged reboiling in the split reboiler may allow for precise control over the distillation, resulting in a more refined final product and improved / desirable flavours. The system's design may maximise heat recovery and utilisation, making the distillation process more sustainable and cost-effective. In aspects of the invention a hot fluid storage tank provides hot fluid via flow line 48 to a hot manifold 44 which in turn provides hot fluid via flow line 53 to the Very High-Temperature Heat Pump (VHTHP) 2 with flow lines 49 and 50 originating from the upper condenser of either a spirit still or wash still as seen in Figures 2 to 4. The hot manifold 44 provides fluid via flow line 53 to the VHTHP 2. The VHTHP 2 through its internal compressor and expansion valve heats the recovered heat from two split condensers, reflux jackets and a hot fluid storage tank to create a high temperature stream 58 of temperatures of up to 200°C. The high temperature stream 54 is then passed through a hot manifold 45 and used for various purposes 58, 59, such as heating the split reboiler, enhancing the overall efficiency of the distillation process, recovering thermal energy from the distillation process and reducing energy consumption. The VHTHP 2 is also fed 55 by a cold manifold 47 which is supplied via flow lines 51, 52 from the lower section of the split reboiler. A cold manifold 46 via flow line 56 which feeds flow line 57. The invention may provide a method and system for recovering energy during an alcohol distillation process. The system may comprise at least one still, at least one reboiler configured to heat distillation fluid in the at least one still, at least one condenser, and at least one heat pump. The at least one heat pump may be configured to heat fluids recovered from the at least one condenser and / or the at least one reboiler. The at least one condenser may comprise a reflux jacket. Throughout the specification, unless the context demands otherwise, the terms 'comprise' or'include', or variations such as 'comprises' or'comprising', 'includes' or 'including' will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers. Furthermore, relative terms such as”, “inlet” .“outlet” and the like are used herein to indicate directions and locations as they apply to the appended drawings and will not be construed as limiting the invention and features thereof to particular arrangements or orientations. The term “outlet” shall be construed as being an opening which, dependent on the direction of the movement of fluid may also serve as an “entry”, and vice versa. The foregoing description of the invention has been presented for the purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise form disclosed. The described embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilise the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Therefore, further modifications or improvements may be incorporated without departing from the scope of the invention as defined by the appended claims.

Claims

1. A heat recovery system for an ethanol distillation process comprising: at least one still;at least one reboiler configured to heat distillation fluid in the at least one still;at least one condenser;at least one heat pump;wherein the at least one heat pump is configured to heat fluids recovered from the at least one condenser and / or the at least one reboiler;wherein the at least one condenser comprises a reflux jacket.

2. The system according to claim 1 wherein the at least one heat pump is a high temperature heat pump or a very high temperature heat pump.

3. The system according to claim 1 or 2 wherein the at least one condenser is configured to cool and recover heat from at least a neck portion of the still.

4. The system according to any preceding claim wherein the at least one condenser further comprises a first condenser configured to cool a fluid to a temperature within a first temperature range and a second condenser configured to cool a fluid in the neck portion to a temperature within a second temperature range.

5. The system according to any of claims 4 wherein the first condenser is configured to cool a fluid from a temperature of approximately 100°C to approximately 70°C and / or wherein the second condenser is configured to cool a fluid from a temperature of approximately 70°C to less than 25°C.

6. The system according to any preceding claim wherein the at least one condenser comprises a split condenser with vertical plates and / or horizontal baffles.

7. The system according to any preceding claim wherein the reflux jacketsurrounds or at least partially surrounds the neck portion of the at least one still.

8. The system according to any preceding claim wherein reflux jacket and / or the at least one condenser is configured to control a temperature of vapour or liquid passing through the neck of the still to control or adjust a flavour of the distillate.

9. The system according to any preceding claim comprising at least two reboiler or reboiler sections.

10. The system according to claim 9 wherein a first reboiler is configured to heat fluid in at least one still using heat from at least one heat source such as a very high temperature heat pump, electric heater, and / or gas heater with the heat medium being pressurised water and / or steam.

11. The system according to claim 10 wherein a first reboiler is configured to heat fluid in at least one still using heat from a solar heating system.

12. The system according to any of claim 10 or 11, wherein a second reboiler is configured to heat a distillation fluid in the least one still using heat from at least one heat pump or very high temperature heat pump.

13. The system according to any preceding claim wherein an outlet from the at least one condenser and / or at least one reboiler is in fluid communication with an inlet of the at least one heat pump.

14. The system according to any preceding claim wherein an outlet from at least one heat pump is in fluid communication with an inlet of at least one reboiler.

15. The system according to any preceding claim wherein the still is a wash still or a spirit still.

16. An ethanol distillation plant comprising at least one heat recovery system according to any of claims 1 to 15.

17. A method of reducing energy consumption in an ethanol distillation process, the method comprising:providing a heat recovery system comprising:at least one still;at least one reboiler configured to heat a distillation fluid in the at least one still;at least one condenser;at least one heat pump;wherein the at least one condenser comprises a reflux jacket;passing fluids from the at least one condenser and / or from the at least one reboiler to the at least one heat pump;heating the fluids in the at least one heat pump and circulating the heated fluids to the at least one reboiler.

18. The method according to claim 17 wherein the fluid is heated to temperatures up to 200°C.

19. The method according to claim 17 or 18 wherein the system comprises a first condenser, wherein the method comprises cooling a fluid in the neck portion and / or a downstream portion of the neck portion from a temperature of approximately 100°C to approximately 70°C in the first condenser.

20. The method according to claim 19 wherein the system comprises a second condenser, wherein the method comprises cooling a fluid in the neck portion and / or a downstream portion of the neck portion from a temperature of approximately 70°C to less than 25°C in the second condenser.

21. The method according to any of claims 17 to 20 comprises heating distillation fluid in at least one still using a first reboiler heated from a heat source such as an electric heater, heat pump, very high temperature heat pump, pressurised water, gas heater, solar heated oil and / or steam.

22. The method according to any of claims 17 to 21 comprising heating distillation fluid in at least one still using a second reboiler heated from heated fluid from the at least one heat pump, electric heater, very high temperature heat pump, pressurised water, gas heater, solar heated oil and / or steam.

23. The method according to any of claims 17 to 22 comprising recovering heat from the neck portion of the at least one still by circulating cold fluid through the reflux jacket surrounding or at least partially surrounding the neck portion of the at least one still.

24. The method according to any of claims 17 to 23 comprising controlling a temperature of the distillation fluid passing through the neck of the at least one still to control and / or adjust a flavour of the distillation fluid.

25. The method according to any of claims 17 to 24 comprising controlling a temperature of a cooling fluid by adjusting flow to match required reflux rates.A

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