초록 ▼

Processes and systems are provided to compress vapors produced in distillation and recover the heat of condensation through mechanical vapor compression and to derive mechanical and electrical energy from a combined heat and power system, while maintaining the plant's original ability to operate. Th

Processes and systems are provided to compress vapors produced in distillation and recover the heat of condensation through mechanical vapor compression and to derive mechanical and electrical energy from a combined heat and power system, while maintaining the plant's original ability to operate. The plant's existing distillation system, steam generation, and electrical demand determine the design basis for the retrofit system that is targeted at an optimized combination of energy usage, energy cost, and environmental impact. Mechanical vapor compression minimizes the total energy usage. Combined heat and power provides a means of converting energy between fuel, electricity, and thermal energy in a manner that best complements plant requirements and energy economics and minimizes inefficiencies and energy losses.

대표청구항 ▼

1. A method of modifying a distillery or biorefinery, wherein said distillery or biorefinery converts biomass into a biofuel or biochemical, and wherein said biofuel or biochemical is purified by distillation, said method comprising: (i) introducing a mechanical vapor recompression (MVR) unit to rec

1. A method of modifying a distillery or biorefinery, wherein said distillery or biorefinery converts biomass into a biofuel or biochemical, and wherein said biofuel or biochemical is purified by distillation, said method comprising: (i) introducing a mechanical vapor recompression (MVR) unit to recover heat of said distillation and provide a reduction in process thermal energy usage in said distillery or biorefinery, wherein said MVR unit comprises multiple compressors and/or multiple compressor stages, and wherein cascaded heat from said distillation is integrated with multiple distillery or biorefinery process stages, including at least one distillery or biorefinery process stage that is not distillation; and(ii) introducing a combined heat and power (CHP) system having a CHP engine, to provide mechanical and electrical energy for driving said MVR unit, wherein residual waste heat of said CHP engine offsets said process thermal energy usage in said distillery or biorefinery, in conjunction with said MVR unit; and wherein integration of said MVR unit with said CHP system balances process energy requirements, process carbon intensity, and/or process energy costs. 2. The method of claim 1, wherein cascaded heat from said distillation is integrated with multiple stillage evaporations, and wherein compressed biofuel or biochemical vapors and/or steam generated in at least one stillage evaporator is compressed and returned to said distillation. 3. The method of claim 1, wherein cascaded heat from said distillation is integrated with vapor-phase dehydration, and wherein compressed biofuel or biochemical vapors as anhydrous vapors and/or steam generated in at least one stillage evaporator is compressed and returned to said distillation. 4. The method of claim 1, wherein cascaded heat from said distillation is integrated with multiple stillage evaporations including a first evaporator, wherein compressed steam from said first evaporator is optionally split between said distillation and a second evaporator, and wherein said distillation and at least one of said first and second evaporators are operated at equal pressure, thereby allowing a compressor stage to cascade heat of evaporation between said distillation and said multiple stillage evaporations. 5. The method of claim 1, wherein cascaded heat from multiple stillage evaporations to said distillation is integrated with compression of steam from at least one reboiler-evaporator to drive said distillation and evaporation, wherein said distillation and said evaporation are operated such that evaporation pressure is higher than distillation pressure, thereby allowing compressor stages to cascade heat of evaporation into said distillation. 6. The method of claim 1, wherein said MVR unit is sized or operated with a standard steam generator to reduce thermal energy required in said distillation, and wherein said standard steam generator is operated at a reduced rate as a result of reduction in steam energy demand due to energy recovered by said MVR unit. 7. The method of claim 1, wherein said CHP engine is sized or operated according to (i) mechanical demand of said MVR unit and (ii) thermal energy demand of said distillery or biorefinery, wherein at least some of said thermal energy demand of said distillery or biorefinery is provided by waste heat recovered by said CHP system. 8. A distillery or biorefinery process comprising the method of claim 1. 9. The distillery or biorefinery process of claim 8, wherein said biofuel or biochemical is selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, n-butanol, isobutanol, 2-butanol, tert-butanol, acetone, and combinations thereof. 10. A system configured for a distillery or biorefinery, wherein said distillery or biorefinery is capable of converting biomass into a biofuel or biochemical, and wherein said distillery or biorefinery includes distillation configured to purify said biofuel or biochemical, said system comprising: (i) a mechanical vapor recompression (MVR) sub-system configured to recover heat of said distillation and provide a reduction in process thermal energy usage in said distillery or biorefinery, wherein said MVR sub-system comprises multiple compressors and/or multiple compressor stages, and wherein cascaded heat from said distillation is integrated with multiple distillery or biorefinery process stages, including at least one distillery or biorefinery process stage that is not distillation; and(ii) a combined heat and power (CHP) sub-system having a CHP engine, configured to provide mechanical and electrical energy for driving said MVR sub-system,wherein said CHP sub-system and said MVR sub-system are integrated and configured so that residual waste heat of said CHP engine offsets said process thermal energy usage in said distillery or biorefinery. 11. The system of claim 10, wherein vapor from said distillation cascades heat to multiple stillage evaporators, and wherein biofuel or biochemical vapors and/or steam generated in at least one stillage evaporator is compressed and returned to said distillation within said distillery or biorefinery. 12. The system of claim 10, wherein said multiple compressors and/or multiple compressor stages are configured to cascade heat of evaporation between said distillation and multiple stillage evaporations, wherein vapor from said distillation provides heat to a first stillage evaporator, and wherein steam generated in said first stillage evaporator is compressed and compressed steam is optionally split between said distillation and a second stillage evaporator. 13. The system of claim 10, wherein said multiple compressors and/or multiple compressor stages are configured to cascade heat of evaporation from multiple stillage evaporators into said distillation, and wherein steam from at least one stillage evaporator is compressed and returned to said distillation and fed to at least one stillage evaporator to drive evaporation. 14. The system of claim 10, wherein said MVR sub-system is configured with a standard steam generator to reduce thermal energy required in said distillation. 15. The system of claim 10, wherein said CHP engine is sized according to (i) mechanical demand of said MVR sub-system and (ii) thermal energy demand of said distillery or biorefinery, wherein waste heat recovered by said CHP system provides at least some of said thermal energy demand of said distillery or biorefinery. 16. The system of claim 10, wherein said biofuel or biochemical is selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, n-butanol, isobutanol, 2-butanol, tert-butanol, acetone, and combinations thereof. 17. The system of claim 10, wherein said system is a retrofit to an existing plant. 18. The system of claim 10, wherein said distillery or biorefinery is a greenfield plant.