Energy efficiency is improved in a grain alcohol production plant (60) by capturing heat energy that otherwise would be lost to the environment when stillage evaporator last effect vapors (22) are condensed to recycle their water content. The low temperature/pressure heat energy of these vapors is efficiently recovered and reused by placing the vapors in direct physical contact (301, 402) with a working fluid (38) to form heated working fluid (54, 66), then using the heated working fluid directly in a process of the plant. In an embodiment, cook water used for the plant fermentation process is preheated by direct contact with stillage evaporator overhead vapor via one or more direct contact heat exchangers (301, 401) and/or a thermocompressor (402).
Energy efficiency is improved in a grain alcohol production plant (60) by capturing heat energy that otherwise would be lost to the environment when stillage evaporator last effect vapors (22) are condensed to recycle their water content. The low temperature/pressure heat energy of these vapors is efficiently recovered and reused by placing the vapors in direct physical contact (301, 402) with a working fluid (38) to form heated working fluid(54,66), then using the heated working fluid directly in a process of the plant. In an embodiment, cook water used for the plant fermentation process is preheated by direct contact with stillage evaporator overhead vapor via one or more direct contact heat exchangers (301, 401 ) and/or a thermocompressor (402).
Energy efficiency is improved in a grain alcohol production plant (60) by capturing heat energy that otherwise would be lost to the environment when stillage evaporator last effect vapors (22) are condensed to recycle their water content. The low temperature/pressure heat energy of these vapors is efficiently recovered and reused by placing the vapors in direct physical contact (301, 402) with a working fluid (38) to form heated working fluid(54, 66), then using the heated working fluid directly in a process of the plant. In an embodiment, cook water used for the plant fermentation process is preheated by direct contact with stillage evaporator overhead vapor via one or more direct contact heat exchangers (301, 401) and/or a thermocompressor (402).
An improvement which reduces the reflux requirement for a fractional distillation system of an alcohol production plant (40, 60, 70, 80). The improvement includes a mixing device (44) for combining a water/alcohol mixture having an enhanced alcohol content (50, 62, 72, 82) with the reflux liquid (16) in the absence of a vapor/liquid equilibrium interface to form a reflux mixture (56) for supply to the rectifier column (14). The mixture having an enhanced alcohol content may be sourced from a location along the rectifier-reflux vapor to liquid system flow path, or from another source.
Waste heat is extracted in two stages from the exhaust (20) of a biomass dryer (14) in a grain alcohol plant (10). A boiler circuit (56) provides a first steam at high pressure. A first energy recovery circuit (36) extracts heat from the exhaust via a non-contact heat exchanger (24) and provides a second, relatively lower pressure steam (78), thereby bypassing a portion of the boiler circuit. Working fluids in the boiler and first energy recovery circuits are maintained within boiler water quality specifications and are intermixed to allow the production of the second steam without a pressure reduction device. A second energy recovery circuit (44) extracts heat from the exhaust downstream of the first energy recovery circuit using a direct contact heat exchanger (38) and provides a non-boiler quality heated fluid (52), which may be a heated liquid or a third steam.
F22B 3/00 - Autres méthodes de production de vapeurChaudières à vapeur non prévues dans les autres groupes de la présente sous-classe
F22B 1/14 - Méthodes de production de vapeur caractérisées par le genre de chauffage par exploitation de l'énergie thermique contenue dans une source chaude la source chaude étant de la vapeur entrant en contact direct avec l'eau dans une enceinte ou avec de l'eau en gouttelettes
F22B 1/16 - Méthodes de production de vapeur caractérisées par le genre de chauffage par exploitation de l'énergie thermique contenue dans une source chaude la source chaude étant un liquide chaud ou une vapeur chaude, p. ex. un liquide résiduel, une vapeur résiduelle
B01D 47/00 - Séparation de particules dispersées dans l'air, des gaz ou des vapeurs en utilisant un liquide comme agent de séparation
A system and method for extracting waste heat from the exhaust (20) of a biomass dryer (14), such as in a grain alcohol plant (10). A boiler circuit (74) provides steam at a high pressure to a balance of the plant (64). A recovered energy circuit (76) extracts heat from the exhaust and provides steam (60) at an intermediate pressure, thereby eliminating the need for a pressure reducing valve in order to satisfy an intermediate pressure steam demand in the plant. Working fluids in the boiler and recovered energy circuits are intermixed in a boiler feed vessel (72).
Waste heat is extracted in two stages from the exhaust (20) of a biomass dryer (14) in a grain alcohol plant (10). A boiler circuit (56) provides high pressure steam to a balance of the plant (54). A first energy recovery circuit (36) extracts heat from the exhaust via a non-contact heat exchanger (24) and provides a first relatively lower pressure steam (78) to the balance of the plant, thereby bypassing a portion of the boiler circuit. Working fluids in the boiler and first energy recovery circuits are maintained within boiler water quality specifications and are intermixed to allow the production of the first relatively lower pressure steam without a pressure reduction device. A second energy recovery circuit (44) extracts heat from the exhaust downstream of the first energy recovery circuit using a direct contact heat exchanger (38) and provides a non-boiler quality heated fluid (52) to the balance of the plant.
F26B 23/02 - Chauffage utilisant un chauffage par combustion
F22B 3/00 - Autres méthodes de production de vapeurChaudières à vapeur non prévues dans les autres groupes de la présente sous-classe
F22B 1/14 - Méthodes de production de vapeur caractérisées par le genre de chauffage par exploitation de l'énergie thermique contenue dans une source chaude la source chaude étant de la vapeur entrant en contact direct avec l'eau dans une enceinte ou avec de l'eau en gouttelettes
F22B 1/16 - Méthodes de production de vapeur caractérisées par le genre de chauffage par exploitation de l'énergie thermique contenue dans une source chaude la source chaude étant un liquide chaud ou une vapeur chaude, p. ex. un liquide résiduel, une vapeur résiduelle
B01D 47/00 - Séparation de particules dispersées dans l'air, des gaz ou des vapeurs en utilisant un liquide comme agent de séparation
Waste heat is extracted from the exhaust (20) of a biomass dryer (14) in a grain alcohol plant (10). A boiler circuit (74) provides high pressure steam to a balance of the plant (64). A recovered energy circuit (76) extracts heat from the exhaust via a dryer exhaust condensing economizer (24) and provides a steam mixture (60) to satisfy an intermediate pressure steam demand of the balance of the plant, thereby bypassing a portion of the boiler circuit. Working fluids in the boiler and recovered energy circuits are intermixed in a boiler feed vessel (72). Dryer exhaust condensate (30) may be used in an exhaust gas scrubber (22) upstream of the dryer exhaust condensing economizer to remove pollutants and to saturate (26) the exhaust gas for improved heat transfer. Heat transfer may be further improved by operating the dryer exhaust condensing economizer at an elevated pressure.
B01D 53/14 - Séparation de gaz ou de vapeursRécupération de vapeurs de solvants volatils dans les gazÉpuration chimique ou biologique des gaz résiduaires, p. ex. gaz d'échappement des moteurs à combustion, fumées, vapeurs, gaz de combustion ou aérosols par absorption
Waste heat is extracted from the exhaust of a biomass dryer in a grain alcohol plant . A boiler circuit provides high pressure steam to a balance of the plant. A recovered energy circuit extracts heat from the exhaust via a dryer exhaust condensing economizer and provides a steam mixture to satisfy an intermediate pressure steam demand of the balance of the plant, thereby bypassing a portion of the boiler circuit. Working fluids in the boiler and recovered energy circuits are intermixed in a boiler feed vessel. Dryer exhaust condensate may be used in an exhaust gas scrubber upstream of the dryer exhaust condensing economizer to remove pollutants and to saturate the exhaust gas for improved heat transfer. Heat transfer may be further improved by operating the dryer exhaust condensing economizer at an elevated pressure.
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