System and method for distillation

The present invention relates to a system and method for distillation to reduce steam consumption has been disclosed. The system comprises of an analyser column 11, multiple pressure booster units (fan set-I 79, fan set-II 24, and fan set-III 29), a rectifier column 15, a plurality of evaporator units (30,12), a splitter unit 05, a plurality of de-superheating units (03, 80), and additional DDGS dryer unit 25. The integration of pressure booster units (fan set-I 79, fan set-II 24, and fan set-III 29) and additional DDGS dryer unit 05 increases the steam (vapor) production and reduces the steam (vapor) consumption in the system from external source and balances the optimization of process energy requirements, energy cost, and process carbon intensity.

CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY

The present application claims priority from Indian patent application number (202221038264) filed on (Jan. 7, 2022), incorporated herein by a reference.

FIELD OF THE INVENTION

The present invention, in general, relates to an ethanol distillation system, and more particularly, relates to an improved ethanol distillation system having multiple sets of pressure booster units.

BACKGROUND OF THE INVENTION

Distillation or classical distillation enables the separation of two or more components or substances from a liquid mixture by using selective boiling and condensation temperatures. Further, the process may also be applied to separate two liquids having a different boiling point.

The distillation process may further be used for obtaining ethanol. The present ethanol distillation system use steam as an energy driver, wherein the steam is generated by burning natural gas/Coal/Fossil Fuel. However, the usage of such carbon-based fuel steam generation increases the greenhouse gas emission value, and the reduction of the energy requirement decreases the CI (Carbon Intensity) number for the production of ethanol.

Thus, there exists a long-felt need to design and develop an improved ethanol distillation system that does not rely on carbon-based fuel for steam generation.

SUMMARY OF THE INVENTION

Before the present disclosure for an improved system and method for ethanol distillation for reduction of steam is described, it is to be understood that this application is not limited to the particular systems, and methodologies described, as there can be multiple possible embodiments which are not expressly illustrated in the present disclosure. It is also to be understood that the terminology used in the description is for the purpose of describing the particular versions or embodiments only and is not intended to limit the scope of the present application. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.

In an implementation of the present disclosure, a method for distillation has been disclosed. The method may include transferring of a preheated feed stream to an analyser column for stripping vapor from the preheated feed stream. Further, compressing the stripped vapor in a fan set-I, in one or more stages to form compressed vapor. Further, transferring the compressed vapor from the fan set-I to a rectifier column and rectifying the compressed vapor in the rectifier column to obtain the rectified vapor. Further, transferring the rectified vapor from the rectifier column to an evaporator unit and condensing the rectified vapor to form rectified condensate in the evaporator unit. Further, transferring the rectified condensate to a dehydration section for further processing to obtain ethanol. The water vapor formed during the condensation process in the evaporator unit may be transferred to further fan set units.

In an implementation of the present disclosure, a system for distillation has been disclosed. The system as disclosed may comprise a preheater, an analyser column, a fan set-I, a rectifier column, and an evaporator unit. The analyser column may be configured to receive a preheated feed stream from the preheater, and may be configured to strip-off the vapor from the received preheated feed stream. Further the fan set-I may be configured to receive the stripped vapor from the analyser column and may be configured to compress the stripped vapor in one or more stages to form a compressed vapor. Further, the rectifier column may be configured to receive the compressed vapor from the fan set-I and may be configured to rectify the compressed vapor to form a rectified vapor. The evaporator unit may be configured to receive the rectified vapor from the rectifier column and may be configured to condense the rectified vapor to form a rectified condensate. Further, the evaporator unit may be configured to transfer the rectified condensate to a dehydration section for further concentration of ethanol from the rectified condensate. The water vapor formed during the condensation process in the evaporator unit may be transferred to further fan set units.

DETAILED DESCRIPTION OF THE INVENTION

Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment,” or “in an embodiment” in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments. Following is an example which is illustrative only and invention accommodates any and every variation of the example provided below that shall serve the same purpose and is obvious to a person skilled in the art.

The present subject matter relates to a system and method for distillation for reduced steam consumption. The system comprises a preheater, an analyser column, a rectifier column, a first and second evaporator units, a first and second de-superheating units, multiple pressure booster units (Fan Set I, II, and III) and an exhaust column. The Fan Set units may comprise a multiple set of fans. The Fan Set units may be placed at multiple locations for pressurizing the vapors and substituting it with fuel-based steam during the distillation cycle. Further, the method may include preheating a fermented wash in the preheater and feeding a preheated feed stream to the analyser column. The analyser column may perform stripping of vapor from the preheated feed stream. Further, the stripped vapor may be fed to the Fan set I. The Fan set I may be configured to pressurise the stripped vapor to obtain compressed vapor in one or more stages. Further, the compressed vapor may be fed to the rectifier column. The compressed vapor may increase the operating pressure and temperature of the rectifier column, and thereby increases throughput of the rectifier column. Also, rectifier may be configured to receive feed from a dehydration section for recovery of ethanol. The rectifier column may be configured to rectify the compressed vapor to obtain rectified vapor. Further, the rectified vapor from rectifier column may be fed to the first evaporator unit for condensation. The first evaporator unit may be configured to fed part of condense vapor to the rectifier as reflux and left over condense vapor to the dehydration section for further concentration of ethanol.

Further, the water vapor from the first evaporator may be fed to the Fan set II. The Fan set II may be configured to pressurise the water vapor to superheated water vapor in one or more stages. The superheated water vapor may be fed to the first de-superheater unit to obtain saturated water vapor. Further the saturated water vapor may be fed to the splitter unit. The splitter unit may be configured to split the saturated water vapor into first and second saturated water vapor streams. Further, the second saturated water vapor stream may be fed to the second evaporator unit. The second evaporator unit may also receive additional saturated water vapor stream from the dehydration section along with second saturated water vapor stream from the splitter unit. Further, the second saturated water vapor stream and additional saturated water vapor stream may be fed to the analyser column to act as a heat source. Further, the first saturated water vapor stream from the splitter unit may be received by the Fan set III. The fan set III may be configured to compress the first saturated water vapor stream in one or more stages to obtain superheated water vapor. Further, the second de-superheater unit may be configured to receive and de-superheat the superheated water vapor to obtain saturated water vapor. The saturated water vapor may be further received by the exhaust column to act as a heat source.

Referring toFIG.1illustrates a system and method for distillation for reduction of Steam, in accordance with an exemplary embodiment. The system100may comprise a preheater13. The preheater may further be connected to an analyser column11. The analyser column11may be further connected to a first pressure booster (Fan Set I unit), wherein the Fan Set I unit may comprise a first set of fans79. The first set of fans79may be configured to increase pressure in one or more stages in series. Further, the first set of fans79may be connected to a rectifier column15. Further, the rectifier column15may be connected to a first evaporator unit30. Further, the first evaporator unit30may be connected to a second pressure booster unit (Fan Set II unit), the Fan Set II unit may comprise a second set of fans24. The second set of fans24may be configured to increase pressure in one or more stages in series. The second set of fans24may be further connected to a first de-superheating unit03. Further, the first de-superheating unit03may be connected to a splitter unit05, the splitter unit may be further connected to a second evaporator unit12and a third pressure booster (Fan Set III unit), the Fan Set III unit may comprise a third set of fans29. The second evaporator unit12may be further connected to the analyser column11and the third set of fans29may be connected to a second de-superheating unit80. Further, the second de-superheating unit80may be connected to an exhaust column14.

Further, in accordance with the exemplary embodiment, a fermented wash19containing 8-20% v/v ethanol concentration may be preheated at 60-70 degree temperature in the feed preheater13to obtain a preheated feed stream20. The preheated feed stream20may be fed to the analyser column11for stripping of ethanol and water stream of the preheated feed stream20to obtain stripped vapor15′ from the top of the analyser column11operating at a pressure of 0.4 to 0.6 bar and at a temperature of 72-75 degree Centigrade. The stripped vapor15′ at top of the analyser column11may contain 45-65% v/v of ethanol and 30-55% of water. Further, the stripped vapor15′ may be compressed by the Fan Set-I79in one or more stages to obtain compressed vapor16at a pressure of 1.2-1.3 bar. The obtained compressed vapor16may comprise ethanol and water stream at pressure 1.2-1.3 bar and flow rate of 33305 kg/h.

Further, the compressed vapor16at a pressure of 1.2-1.3 bar, at a temperature of 140-160 degree, and at a flow rate of 33305 kg/h may be transferred to the rectifier column15by the fan set-I79for the further rectification process. The transfer of high pressure and high temperature compressed vapor16to the rectifier column15may increase operating pressure and of rectifier column15and thereby may result in higher throughput to obtain rectified vapor99. The rectified vapor99having temperature between 80-90 degree, pressure between 1.10-1.20 bar, and flowrate of 71710 kg/h present at the top of the rectifier column15may be further transferred to the first evaporator unit30for condensation process. The rectified vapor99may be condensed to form rectified condensate48in the first evaporator unit30.

The part of rectified condensate48from the first evaporator unit30may be transferred back to the rectifier column15as a reflux17and the remaining rectified condensate48may be transferred to dehydration section89for further concentration of ethanol from the rectified condensate48. After condensation process the first evaporator unit30may comprise of water vapor49at temperature between 65-75-degree, pressure 0.2-0.4 Bar, and flowrate of 27520 kg/h. The water vapors49present at the top of the first evaporator unit30may be transferred to the Fan Set-II24. The Fan Set-II24may be configured to compress the water vapor49from 0.3 bar to 0.9 bar to obtain superheated water vapor42in one or more stages.

The superheated water vapors42may be received by the first de-superheating unit03. The first de-superheating unit03may be configured to de-superheat the superheated water vapor42to obtain saturated water vapor53. Further, the saturated water vapor53may be received by the splitter unit05. The splitter unit05may be configured to split the saturated water vapor53into saturated first water vapor stream21and saturated second water vapor stream08. Further the saturated second water vapor stream08at the pressure between 0.8-0.10 bar, temperature 96-99 degree, and flow rate of 20100 kg/h may be transferred to the second evaporator unit12by the splitter unit05. Further, the second evaporator unit12may be configured to receive an additional saturated water vapor stream90from the dehydration section89. The additionally received saturated water vapor stream90from the dehydration section89and saturated second water vapor stream08received from the splitter unit05may combine to form combined saturated water vapor43. The second evaporator unit12may be configured to transfer the combined saturated water vapor43at a pressure of 0.4-0.6 bar, temperature of 80-90 degree, and flow rate of 24300 kg/h back to the analyser column11to make combined saturated water vapor43may act as a heat source.

Further the splitter unit05may be configured to transfer the saturated first water vapor stream21at a pressure of 0.8-0.10 bar and flow rate of 9800 kg/h to the fan set-III29. The fan set-III29may be configured to compress the saturated first water vapor stream21to a pressure of 2.1 bar to form superheated water vapor07at flow rate of 9821 kg/h. Further, the superheated water vapor07may be transferred to second de-superheating unit80. The second de-superheating unit80may be configured to de-superheat the superheated water vapor07to obtain saturated water vapor06at pressure of 2.1 bar, temperature of 127° C. and flowrate of 10471 kg/h. The saturated water vapor06at flow rate of 6800 kg/h may be received by the exhaust column14to make saturated water vapor06may act as a heat source.

Referring toFIG.2illustrates a system and method for distillation for reduction of steam, in accordance with an exemplary embodiment. The system100may comprise a preheater13. The preheater may further be connected to an analyser column11. The analyser column11may be further connected to a first pressure booster (Fan Set I unit), wherein the Fan Set I unit may comprise a first set of fans79. The first set of fans79may be configured to increase pressure in one or more stages in series. Further, the first set of fans79may be connected to a rectifier column15. Further, the rectifier column15may be connected to a first evaporator unit30. Further, the first evaporator unit30may be connected to a second pressure booster unit (Fan Set II unit), the Fan Set II unit may comprise a second set of fans24. The second set of fans24may be configured to increase pressure in one or more stages in series. The second set of fans24may be further connected to a first de-superheating unit03. Further, the first de-superheating unit03may be connected to a splitter unit05, the splitter unit may be further connected to a second evaporator unit12and a third pressure booster (Fan Set III unit), the Fan Set III unit may comprise a third set of fans29. The second evaporator unit12may be further connected to the analyser column11and the third set of fans29may be connected to a second de-superheating unit80. Further, the second de-superheating unit80may be connected to an exhaust column14, a liquefaction section90, and a dehydration section89.

Further, in accordance with the exemplary embodiment, a fermented wash19containing 8-20% v/v ethanol concentration may be preheated at 60-70 degree temperature in the feed preheater13to obtain a preheated feed stream20. The preheated feed stream20may be fed to the analyser column11for stripping of ethanol and water stream of the preheated feed stream20to obtain stripped vapor15′ from the top of the analyser column11operating at a pressure of 0.4 to 0.6 bar and at a temperature of 72-75 degree Centigrade. The stripped vapor15′ at top of the analyser column11may contain 45-65% v/v of ethanol and 30-55% of water. Further, the stripped vapor15′ may be compressed by the Fan Set-I79in one or more stages to obtain compressed vapor16at a pressure of 1.2-1.3 bar. The obtained compressed vapor16may comprise ethanol and water stream at pressure 1.2-1.3 bar and flow rate of 33305 kg/h.

Further, the compressed vapor16at a pressure of 1.2-1.3 bar, at a temperature of 140-160 degree, and at a flow rate of 33305 kg/h may be transferred to the rectifier column15by the fan set-I79for the further rectification process. The transfer of high pressure and high temperature compressed vapor16to the rectifier column15may increase operating pressure and of rectifier column15and thereby may result in higher throughput to obtain rectified vapor99. The rectified vapor99having temperature between 80-90 degree, pressure between 1.10-1.20 bar, and flowrate of 71710 kg/h present at the top of the rectifier column15may be further transferred to the first evaporator unit30for condensation process. The rectified vapor99may be condensed to form rectified condensate48in the first evaporator unit30.

The part of rectified condensate48from the first evaporator unit30may be transferred back to the rectifier column15as a reflux17and the remaining rectified condensate48may be transferred to the dehydration section89for further concentration of ethanol from the rectified condensate48. After condensation process the first evaporator unit30may comprise of water vapor49at temperature between 65-75-degree, pressure 0.2-0.4 Bar, and flowrate of 27520 kg/h. The water vapors49present at the top of the first evaporator unit30may be transferred to the Fan Set-II24. The Fan Set-II24may be configured to compress the water vapor49from 0.3 bar to 0.9 bar to obtain superheated water vapor42in one or more stages.

The superheated water vapor42may be received by the first de-superheating unit03. The first de-superheating unit03may be configured to de-superheat the superheated water vapor42to obtain saturated water vapor53. Further, the saturated water vapor53may be received by the splitter unit05. The splitter unit05may be configured to split the saturated water vapor53into saturated first water vapor stream21and saturated second water vapor stream08. Further the saturated second water vapor stream08at the pressure between 0.8-0.10 bar, temperature 96-99 degree, and flow rate of 20100 kg/h may be transferred to the second evaporator unit12by the splitter unit05. Further, the second evaporator unit12may be configured to receive an additional saturated water vapor stream90from the dehydration section89. The additionally received saturated water vapor stream90from the dehydration section89and saturated second water vapor stream08received from splitter unit05may combine to form combined saturated water vapor43. The second evaporator unit12may be configured to transfer the combined saturated water vapor43at a pressure of 0.4-0.6 bar, temperature of 80-90 degree, and flow rate of 24300 kg/h back to the analyser column11to make combined saturated water vapor43may act as a heat source.

Further the splitter unit05may be configured to transfer the saturated first water vapor stream21at a pressure of 0.8-0.10 bar and flow rate of 9800 kg/h to the fan set-III29. The fan set-III29may be configured to compress the saturated first water vapor stream21to a pressure of 2.1 bar to form superheated water vapor07at flow rate of 9821 kg/h. Further, the superheated water vapor07may be transferred to second de-superheating unit80. The second de-superheating unit80may be configured to de-superheat the superheated water vapor07to obtain saturated water vapor06at pressure of 2.1 bar, temperature of 127° C. and flowrate of 10471 kg/h, a saturated water vapor41for the liquefaction section90at flowrate of 3671 kg/h, and a saturated water vapor24for the dehydration section89. The saturated water vapor06at flow rate of 6800 kg/h may be received by the exhaust column14, the saturated water vapor41may be received by the liquefaction section90, and the saturated water vapor24may be received by the dehydration section89to act as a heat source.

Referring toFIG.3illustrates a DDGS dryer system associated with the system and method for distillation for reduction of steam, in accordance with an exemplary embodiment. The system100may comprise a preheater13. The preheater may further be connected to an analyser column11.

The analyser column11may be further connected to a first pressure booster (Fan Set I unit), the Fan Set I unit may comprise a first set of fans79. The first set of fans79may be configured to increase pressure in one or more stages in series. Further, the first set of fans79may be connected to a rectifier column15. Further, the rectifier column15may be connected to a first evaporator unit30. The first evaporator unit30may be connected to a second pressure booster unit (Fan Set II unit), the Fan Set II unit may comprise a second set of fans24. The second set of fans24may be configured to increase pressure in one or more stages in series. Further an additional DDGS dryer unit25may also be connected to the second set of fans24through a scrubbing unit10. The second set of fans24may be further connected to a first de-superheating unit03. Further, the first de-superheating unit03may be connected to a splitter unit05, the splitter unit may be further connected to a second evaporator unit12and a third pressure booster (Fan Set III unit), the Fan Set III unit may comprise a third set of fans29. The second evaporator unit12may be further connected to the analyser column11and the third set of fans29may be connected to a second de-superheating unit80. Further, the second de-superheating unit80may be connected to an exhaust column14, a liquefaction section90, and a dehydration section89.

Further, in accordance with the exemplary embodiment, a fermented wash19containing 8-20% v/v ethanol concentration may be preheated at 60-70 degree temperature in the feed preheater13to obtain a preheated feed stream20. The preheated feed stream20may be fed to the analyser column11for stripping of ethanol and water stream of the preheated feed stream20to obtain stripped vapor15′ from the top of the analyser column11operating at a pressure of 0.4 to 0.6 bar and at a temperature of 72-75 degree Centigrade. The stripped vapor15′ at top of the analyser column11may contain 45-65% v/v of ethanol and 30-55% of water. Further, the stripped vapor15′ may be compressed by the Fan Set-I79in one or more stages to obtain compressed vapor16at a pressure of 1.2-1.3 bar. The obtained compressed vapor16may comprise ethanol and water stream at pressure 1.2-1.3 bar and flow rate of 33305 kg/h.

Further, the compressed vapor16at a pressure of 1.2-1.3 bar, at a temperature of 140-160 degree, and at a flow rate of 33305 kg/h may be transferred to the rectifier column15by the fan set-I79for the further rectification process. The transfer of high pressure and high temperature compressed vapor16to the rectifier column15may increase operating pressure and of rectifier column15and thereby may result in higher throughput to obtain rectified vapor99. The rectified vapor99having temperature between 80-90 degree, pressure between 1.10-1.20 bar, and flowrate of 71710 kg/h present at the top of the rectifier column15may be further transferred to the first evaporator unit30for condensation process. The rectified vapor99may be condensed to form rectified condensate48in the first evaporator unit30.

The part of rectified condensate48from the first evaporator unit30may be transferred back to the rectifier column15as a reflux17and the remaining rectified condensate48may be transferred to the dehydration section89for further concentration of ethanol from the rectified condensate48. After condensation process the first evaporator unit30may comprise of water vapor49at temperature between 65-75-degree, pressure 0.2-0.4 Bar, and flowrate of 27520 kg/h. The water vapor49present at the top of the first evaporator unit30may be transferred to the Fan Set-II24. Further the DDGS dryer unit25may transfer a dryer water vapor60to the scrubbing unit10. The scrubbing unit10may be configured to purify the dryer water vapor60to obtain purified water vapor46. The Fan Set-II24may be configured to receive the water vapor49from the first evaporator unit30and purified water vapor46from the scrubbing unit10. The water vapor49may be at 0.2-0.4 bar pressure, flow rate of 27520 kg/h, and temperature of 65-75 degree and purified water vapor46may be at 0.2-0.4 bar pressure, flow rate of 13750 kg/h, and temperature of 70-80 degree may get compressed by the Fan Set-II24in one or more stages to obtain superheated water vapor42at pressure 0.7-0.9 bar and flow rate of 41270 kg/h.

The superheated water vapor42may be received by the first de-superheating unit03. The first de-superheating unit03may be configured to de-superheat the superheated water vapor42to obtain saturated water vapor53. Further, the saturated water vapor53may be received by the splitter unit05. The splitter unit05may be configured to split the saturated water vapor53into saturated first water vapor stream21and saturated second water vapor stream08. Further the saturated second water vapor stream08at the pressure between 0.7-0.9 bar, temperature 120-130 degree, and flow rate of 20100 kg/h may be transferred to the second evaporator unit12by the splitter unit05. Further, the second evaporator unit12may be configured to receive an additional saturated water vapor stream90from the dehydration section89. The additionally received saturated water vapor stream90from the dehydration section89and saturated second water vapor stream08received from splitter unit05may combine to form combined saturated water vapor43. The second evaporator unit12may be configured to transfer the combined saturated water vapor43at a pressure of 0.4-0.6 bar, temperature of 80-90 degree, and flow rate of 24300 kg/h back to the analyser column11to make combined saturated water vapor43may act as a heat source.

Further the splitter unit05may be configured to transfer the saturated first water vapor stream21at a pressure of 0.7-0.9 bar, temperature of 90-100 degree, and flow rate of 24716 kg/h to the fan set-III29. The fan set-III29may be configured to compress the saturated first water vapor stream21to a pressure of 2.1 bar to form superheated water vapor07at flow rate of 26516 kg/h. Further, the superheated water vapor07may be transferred to second de-superheating unit80. The second de-superheating unit80may be configured to de-superheat the superheated water vapor07to obtain saturated water vapor06at pressure of 2.1 bar, temperature of 127° C. and flowrate of 26516 kg/h, a saturated water vapor41for the liquefaction section90at flowrate of 3671 kg/h, and a saturated water vapor24for the dehydration section89. The saturated water vapor06at flow rate of 6800 kg/h may be received by the exhaust column14, the saturated water vapor41may be received by the liquefaction section90, and the saturated water vapor24may be received by the dehydration section89to act as a heat source.

The implementation of the above schematics may reduce steam consumption in the liquefication and dehydration section (not shown in the figure) due to additional water vapor fed from Fan Set III. Wherein, the additional water vapor may be generated by the association of DDGS Dryer with the current system. Further reduction of steam consumption in the liquefication and dehydration section may be configured to balance the optimization of process energy requirements, energy cost, and process carbon intensity.

The foregoing description shall be interpreted as illustrative and not in any limiting sense. A person of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure. The embodiments, examples and alternatives of the preceding paragraphs or the description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments unless such features are incompatible.

The improved system and method for ethanol distillation of the present subject matter has, but is not limited to, the following benefits/advantages:No steam required.useful for ethanol concentration and moisture removal.pressure booster units compress intermediate stream (Mash Column top vapors) instead of using biofuel steam.Increased pressure of rectifier column leads to additional distillation capacity and leading to modernization of ethanol plant capacity.reduction of steam consumption in the liquefication and dehydration section due to additional water vapors generated in the Fan Set II unit and Fan Set III unit reduces the dependency of the system on additional fuel-generated steam from outside sources.optimizes process energy requirements, energy cost, and process carbon intensity

LIST OF REFERENCE NUMERALS