Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
  • B01D3/001—Processes specially adapted for distillation or rectification of fermented solutions
  • B01D3/003—Rectification of spirit
  • B01D3/004—Rectification of spirit by continuous methods
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
  • B01D3/14—Fractional distillation or use of a fractionation or rectification column
  • B01D3/143—Fractional distillation or use of a fractionation or rectification column by two or more of a fractionation, separation or rectification step
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
  • B01D3/14—Fractional distillation or use of a fractionation or rectification column
  • B01D3/143—Fractional distillation or use of a fractionation or rectification column by two or more of a fractionation, separation or rectification step
  • B01D3/146—Multiple effect distillation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
  • B01D3/14—Fractional distillation or use of a fractionation or rectification column
  • B01D3/143—Fractional distillation or use of a fractionation or rectification column by two or more of a fractionation, separation or rectification step
  • B01D3/148—Fractional distillation or use of a fractionation or rectification column by two or more of a fractionation, separation or rectification step in combination with at least one evaporator
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
  • B01D3/14—Fractional distillation or use of a fractionation or rectification column
  • B01D3/32—Other features of fractionating columns ; Constructional details of fractionating columns not provided for in groups B01D3/16 - B01D3/30
  • B01D3/322—Reboiler specifications
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E50/00—Technologies for the production of fuel of non-fossil origin
  • Y02E50/10—Biofuels, e.g. bio-diesel

Definitions

• the invention relates to a separation process, in particular a distillation of ethanol as a final product from a mash.
• Distillation column the mash is evaporated, whereby solid components can be removed as bottoms with water. A part of this bottom product is usually recycled to the distillation column after heating (reboiler).
• the first vaporous distillate, still containing water, ethanol and fusel oil is, if necessary. via a collecting and mixing tank, fed to a second distillation column, which is designed as a rectification column.
• a second distillation column which is designed as a rectification column.
• Rectification carried a more extensive separation, in which the fuselages are discharged in a side stream.
• a small proportion is returned to the rectification column again after heating (reboiler) and otherwise also removed, so that it exudes from the production process.
• the distillate of the second distillation column still containing water and ethanol, can be partially recycled to the first and second distillation column, if necessary. over the already mentioned collection tank.
• the predominant amount of the ethanol-water mixture constituting the second distillate of about 95% ethanol and 5% water undergoes a final dehydration to obtain as pure as possible a purity of 99 to 99.8% ethanol.
• This last dehydration occurs by means of molecular sieves, in which crystalline zeolites adsorb spongy H 2 O molecules.
• the zeolites of a molecular sieve are rapidly saturated in water. For a constant dehydration therefore water-saturated zeolites must be regenerated.
• molecular sieves are regularly used in pairs. It can then be provided by a first active molecular sieve high purity ethanol, which can also be used for the regeneration of a second, passive molecular sieve. In the regeneration of a passive molecular sieve, the ethanol used there can be recycled to a distillation column, this reflux can be about 30% of the obtained pure ethanol of the active molecular sieve.
• the constant change of the pressure load of the molecular sieves causes a dusty abrasion of the filling material. This burdens downstream plant stages, which must be completely replaced periodically. This is reflected adversely in investment and operating costs.
• the object of the invention is to provide a separation process by means of which the economic efficiency, in particular in the dehydrogenation of ethanol from a mash, is markedly improved.
• the separation method according to the invention has a number of advantages.
• the energetic concept of a distillation plant was determined by the design of the stripper, so according to the invention the first distillation stage is operated according to the energetic specifications of the rectification column, which can thus be operated optimally. It thus determines the energy balance of the rectification column essentially that of the first distillation stage.
• the feed is merely separated into two streams, so that both streams have similar energetic and / or chemical potentials, which streams are then fed to a respective distillation column. Also, most of the volume flow of the two streams will move in the same order of magnitude, each about half, but it may be appropriate in individual cases, depending on the configuration of the first and second distillation stage to specify the volume flows differently.
• Process flow back distillation column is returned to a stripper as a front, improves the energy balance per liter of end product over conventional methods already by about 40%. If the feed is split equally into two streams and two strippers are provided in the first distillation stage, a stream is alternatively fed to each stripper, wherein then preferably the volume flows of the two streams are also about the same size. Is then still thought in a preferred embodiment, that a bottom product of a preferably operated at high pressure first stripper is fed to a preferably subjected to a lower pressure second stripper and further in that the distillate of the rectification in a
• Membrane filtration device is cleaned, the energy balance improves by more than 60%
• Retentate for example, a membrane separator in a stream of a stripper and the permeate are fed in a stream of a rectification column.
• this stream with the elevated temperature becomes, in particular, a retentate, for example, a membrane separation device
• Stripper preferably supplied at the top and is with the distillate of this stripper to the rectification.
• the feed of the stream of lower temperature then takes place as permeate, for example, in a lower region of the stripping column.
• a vapor phase generating separation device may be provided as an evaporator, in particular by a relaxation of a vapor phase generating or as a distillation column whose distillate is then present with the distillate of a stripper to the rectification and their bottom product to the stripper next a further stream of the feed is still supplied.
• Separation method according to the invention used in an optimal manner, since the operation of the first distillation stage is completely determined by the rectification and the heat recovery from a final product.
• distillation columns are preferably run at different operating pressures, in particular with those which allow optimal heat recovery. This ensures the lowest possible heat loss.
• the heat recovered from the heat recovery from the final product is fed into the reboiler circuit of the operated at a medium energy level distillation column.
• the heat recovered from the final product can be significantly increased if the concentration of the final product in a feed is at least 20%. It is then possible to significantly reduce the energy input of the overall system in relation to the amount of final product obtained. Such an increase, for example, of an ethanol content of about 10% in one feed can be achieved by a corresponding fermentation technique. Alternatively, upstream processes are possible, for example, that the feed to a previously explained
• Membrane separation process has an increased proportion of the final product. As a result of these measures, the proportion of the end product in the entire system increases significantly. These measures further lead to a significantly increased output of the end product and thus also to an increased heat recovery, which can then be reintroduced into the process.
• Rectifying be purified in molecular sieves or preferably in a membrane separation process in a filtration device.
• a regenerate of this a rectification in the Process flow subsequent filter device is fed into a stripper again.
• Fig. 3 a further arrangement of three
• Fig. 4 variants of a feed of a Renegats a
• Fig. 9 a splitting into a liquid and a vapor phase by means of a distillation column and 10: a variant of this.
• two strippers 1, 2 connected in parallel form a first distillation stage for a separation process, for example for the distillation of ethanol from a beer mash whose inflow 3, comprising about 11.5% ethanol, divided into two streams 40, 41 is more similar chemical and energetic potentials the two strippers 1,2 is fed in equal parts.
• the distillate 4 of the two strippers 1,2 is fed together to a rectification column 5.
• distillate 6 is purified by molecular sieves 7 and discharged as, for example, high-purity methanol of a purity of 99.6% as product stream 8.
• the rectification column 5 is driven to the highest energy level. For example, approx. 18,000 kW of primary energy 9 are fed in, indicated by the heat exchanger in the reboiler cycle of the rectification column 5. An excess of energy of about 9,800 kW is present, which is indicated via a heat exchanger 10 in the return 12 of the rectification column 5 Part is fed into the stripper 2, so that it can be driven at a medium energy level.
• Required for the operation of the stripper 2 are only about 8,500 kW, so that about 1,300 kW unused can be discharged from the circulation, indicated by the heat exchanger 11 in the return 12th
• the stripper 1 is operated with the excess energy of the stripper 2, for which approximately 6,500 kW are required with a surplus of about 6,900 kW of the stripper 2, so that here again about 400 kW of excess energy can be discharged.
• a portion of the excess energy can be used for the regeneration and operation of the molecular sieves 7.
• distillate is ethanol
• a production rate of 19.57 l / h can be achieved with 1.58 kg steam / 1 ethanol in this calculation example.
• distillation columns are driven 1,2,5 with graduated, different pressures.
• an optimal operation of the distillation columns 1,2 and 5 is possible with an optimal energy transfer.
• both strippers 19, 20 are essentially to be operated in accordance with the specifications of the preceding exemplary embodiment.
• the feed 25 contains a proportion of the end product, for example ethanol, at a level of 20%.
• the amount of distillate 26 of the two strippers 27, 28 will be significantly increased, with slightly increased energy requirements and equal working pressures.
• the rectification column 29 is acted upon at unchanged pressure with a primary energy 30 of about 14,500 kW, of which in the return 31 about 2,500 kW for the operation of the stripper 28 are available.
• the distillate 32 supplied to a membrane filtration device 33 has an energy content of about 12,500 kW in the case of, for example, an ethanol content of 80%.
• Permeats 34 flow to the rectification column 29 thereof about 4,700 kW. This leaves about 7,800 kW in the product stream 35, which, indicated by the heat exchanger 36, can be fed into the reboiler circuit 37 for the operation of the stripper 28, the here an energy requirement of Approximately 9,700 kW has an excess of 8,300 kW for the operation of the stripper 27, which requires only about 8,050 kW. Thus, enough energy is provided for the energetically cascaded strippers 27, 28, 29. In addition, the product stream 35 increases significantly to 30.46 l / h. This with an energy input of 0.83 kg of steam per liter of ethanol produced.
• Figure 4 shows two strippers 42,43, which are acted upon by two similar streams 44,45 of an inlet 46.
• the distillate 47 of the two strippers 42, 43 is fed to a rectification column 48 and its distillate 39 to a filtration device 49.
• a renewed feed of a regenerate 50 of the filter 49, in particular again a membrane filtration device is carried out in this embodiment not in the rectification column 48, but in one of the stripper 42,43, indicated by dashed lines in the drawing.
• both strippers 42, 43 can also be charged with the regenerate 50.
• the streams 44, 45 of the same chemical and energetic potential are introduced by way of example in an upper region of the columns of the strippers 42, 43, and the distillate 47 of the strippers 42, 43 is introduced approximately in the center of the rectification column 48.
• the two streams 53, 54 are fed into the stripper 51 and the rectification column 52.
• the volume flows of the two streams 53, 54 also differ significantly from each other.
• the bottom product 55 of the rectification column 52 is from the
• FIG. 6 shows the division of an inlet 56 into two streams 57, 58 by a separating device 59.
• Separator 59 formed for example by sieves, filters, membranes, centrifuges or the like, provides on the one hand for a significant increase in the proportion of the final product, for example. Ethanol, in the stream 57, which is supplied to a stripper 60.
• this stream 57 will usually only have a low solids content or even be solids-free.
• Suitably designed separating devices 61 may be, for example, evaporators and, in particular, strippers 85, for example, shown in FIG. 9.
• Figure 8 shows a variant in which an inlet 66 is divided into two similar streams 67,68. The stream 68 is fed directly to a stripper 86.
• the other stream 67 is again divided by a separating device 69 into two further streams 70, 71, of which the stream 70 present in particular in the vapor phase is supplied again to the stripper 86 on the top side and is present with the distillate at the rectification column 87.
• the stream 71 can still be supplied to the stripper 86 and thus remain within the process.
• a stripper 85 is provided as the separating device. While the distillate 72 of the stripper 85 of elevated temperature, in particular vapor phase, a stripper 73 is fed to the top and is present with the distillate at the rectification column 88, a feed of the bottom product 74 of the stripper 85 in the stripper 73rd
• the stripper 73 is further supplied with a further, branched stream 75 of the feed still.
• the distillation column 65 is driven at a higher pressure than the stripper 73.
• FIG. 10 shows how two strippers 79, 80 are acted upon by an inlet 76, divided into two identical streams 77, 78.
• Their distillate 81 is, for example, summarized as shown, fed to a further distillation column 82. Its bottom product 83 is then introduced into a rectification column 84.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Preparation Of Compounds By Using Micro-Organisms (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=36791774

Family Applications (1)

Country Status (9)

Families Citing this family (114)

Family Cites Families (9)

• 2006
  • 2006-04-19 CN CNA2006800135799A patent/CN101163528A/zh active Pending
  • 2006-04-19 DE DE112006001685T patent/DE112006001685A5/de not_active Withdrawn
  • 2006-04-19 BR BRPI0610023-6A patent/BRPI0610023A2/pt not_active IP Right Cessation
  • 2006-04-19 JP JP2008506921A patent/JP2008536503A/ja not_active Withdrawn
  • 2006-04-19 EP EP06722799A patent/EP1888193A1/de not_active Withdrawn
  • 2006-04-19 CA CA002605570A patent/CA2605570A1/en not_active Abandoned
  • 2006-04-19 US US11/918,919 patent/US20080135396A1/en not_active Abandoned
  • 2006-04-19 RU RU2007142494/15A patent/RU2007142494A/ru not_active Application Discontinuation
  • 2006-04-19 WO PCT/DE2006/000680 patent/WO2007095875A1/de active Application Filing

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events