A distillation apparatus and process for baijiu (Chinese liquor)

Abstract

The application discloses a liquor distillation device and process, which comprises a distillation and steaming device, a first condenser and a steam permeation membrane assembly. The inlet of the distillation and steaming device is connected with a steam pipeline, and the outlet of the distillation and steaming device is connected with the first condenser and the steam permeation membrane assembly through valves respectively. The steam permeation membrane assembly comprises a high-temperature-resistant and solvent-resistant steam permeation membrane, and the permeation side outlet of the steam permeation membrane assembly is connected with the first condenser. The device and process combine high-temperature distillation and membrane steam permeation technology, optimize the existing liquor distillation process, realize efficient and low-energy-consumption liquor purification and recovery, and improve the added value. The liquor distillation device and process can separate liquor steam directly through the membrane assembly, reduce the energy consumption in the liquid-vapor phase change process, and use a traditional tap water heat exchange condensing system in the condensing process, which is helpful to further reduce the cost.

Description

Technical Field

[0001] This invention belongs to the field of brewing technology, and in particular relates to a distillation apparatus and process for baijiu (Chinese white liquor). Background Technology

[0002] Strong-aroma baijiu, one of the four basic aroma types of traditional Chinese baijiu, occupies over 70% of the consumer market due to its rich cellar aroma, mellow and sweet taste, harmonious flavor, and clean finish. In the traditional baijiu distillation process, the "tails" (or "tails") are often produced using the "watching the flowers and picking the spirit" method. These tails typically account for 20% to 25% of the total baijiu production, with an alcohol content of around 30% vol. Compared to the original spirit, the tails have a lower alcohol content and lower levels of alcohol-soluble substances such as most esters and alcohols, while having higher levels of water-soluble components such as ethyl lactate and some organic acids. Due to issues like the inverted emulsion, the tails often suffer from mixed flavors, an unclean finish, insufficient aroma, and a strong sour and astringent taste. Currently, most companies return them to the distillation pot for re-distillation. This process not only results in the loss of alcohol and aroma components but also fails to fully utilize the beneficial components in the tails.

[0003] Membrane separation technology has been widely used in the beverage production industry, such as for aseptic filtration, beer recycling, and non-alcoholic beer production in beer production. Nutritional and health-promoting wines prepared using ultrafiltration membrane separation technology can adsorb components such as fusel oils in baijiu (Chinese white liquor), resulting in a pure taste and less likely to cause headaches. Furthermore, ultrafiltration membranes are also used in the filtration of grape juice and wine, effectively removing bacteria and improving product quality stability. The application of microfiltration and ultrafiltration technologies in baijiu can effectively remove sediment caused by cooling and alcohol reduction, preventing turbidity during shelf life. While pervaporation membranes have some applications in improving baijiu quality, they are not economical for handling tail liquor. The tail liquor must first be condensed and then preheated before entering the membrane system for processing, involving multiple phase change processes, resulting in high overall energy consumption. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a distillation apparatus and process for baijiu (Chinese liquor). This apparatus and process combine high-temperature distillation and membrane vapor permeation technology, optimizing existing baijiu distillation processes. It enables efficient, low-energy purification and recovery of the tail liquor, thereby increasing its added value. Using the apparatus and process of this invention for baijiu distillation, the tail liquor vapor can be directly separated through a membrane module, reducing energy consumption during the liquid-vapor phase transition. Furthermore, the use of a traditional tap water heat exchange condensation system during the condensation process further helps to reduce costs.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A distillation apparatus for baijiu (Chinese liquor) includes a grain distillation and steaming device, a first condenser, and a vapor permeation membrane module. The inlet of the grain distillation and steaming device is connected to a steam pipe, and the outlet of the grain distillation and steaming device is connected to the first condenser and the vapor permeation membrane module respectively via valves.

[0007] The vapor permeation membrane assembly includes a high-temperature and solvent-resistant vapor permeation membrane, and the permeation-side outlet of the vapor permeation membrane assembly is connected to the first condenser.

[0008] Preferably, the outlet of the first condenser is connected to the head wine tank, the main wine tank, and the active ingredient tank via valves.

[0009] Preferably, the osmotic side outlet of the vapor permeation membrane assembly is connected to the tail wine tank via a second condenser.

[0010] Preferably, the outlet of the distillation and steaming device is connected to the first condenser and the vapor permeation membrane assembly respectively via a three-way switching valve.

[0011] Preferably, the outlet of the first condenser is connected to a vacuum device. The vacuum device provides the driving force for the vapor permeation operation.

[0012] Preferably, the condensing medium of the first condenser is water.

[0013] Preferably, the condensing medium of the second condenser is water.

[0014] Preferably, the high-temperature resistant and solvent-resistant vapor permeation membrane is a composite membrane, which is prepared by the following steps:

[0015] (1) Pretreatment of PAN base film: Immerse the PAN base film in an alkaline solution to generate polar groups on the surface of the PAN base film; then heat treat to obtain a pretreated base film; the alkaline solution is a NaOH solution with a concentration of 0.3-1M; the heat treatment is as follows: after the PAN base film is unfolded, it is treated at 120-180℃ for 10-30 minutes, and then naturally cooled. This process is repeated 3 times.

[0016] (2) Preparation of deeply cross-linked precast film solution: After uniformly mixing the n-heptane solution of hydroxy vinyl silicone oil and tetraethoxysilane, tetrabutyltin is added as a catalyst and stirred until the viscosity of the mixture reaches 20 mPa·s to obtain the deeply cross-linked precast film solution.

[0017] (3) Preparation of casting solution: After uniformly mixing the pre-casting solution with hydrogen-containing silicone oil, add Caster PT5000-TMDVDS600 as a platinum-based catalyst and stir until the viscosity of the mixture reaches 30 mPa·s to complete the cross-linking and obtain the casting solution.

[0018] (4) Preparation of vapor permeation membrane: The casting solution obtained in step (4) is coated on the surface of the pretreated base membrane obtained in step (1), and crosslinked at 120-140℃ for 4-6 hours to obtain the high temperature resistant and solvent resistant vapor permeation organic membrane.

[0019] Preferably, the PAN molecular weight of the PAN base film is 400,000 to 500,000.

[0020] Preferably, in step (2), the mass ratio of hydroxyvinyl silicone oil to n-heptane in the n-heptane solution of hydroxyvinyl silicone oil is 6-12:88-94.

[0021] Preferably, the mass ratio of the crosslinking agent to the hydroxyvinyl silicone oil solution in step (2) is 1-3:7-9.

[0022] Preferably, the mass of the catalyst in step (2) is 0.01 to 1% of the mass of the hydroxyvinyl silicone oil solution.

[0023] Preferably, the mass of the hydrogen-containing silicone oil in step (3) is 0.5 to 2% of the mass of the hydroxyvinyl silicone oil solution.

[0024] Preferably, the mass of the platinum-based catalyst in step (3) is 0.1 to 0.3% of the hydrogen-containing silicone oil.

[0025] Preferably, the coating thickness in step (4) is 60–90 μm.

[0026] This invention also provides a distillation process for baijiu using the above-mentioned baijiu distillation apparatus, comprising the following steps:

[0027] Step 1: Input the raw material for distillation into the distillation and steaming device, and introduce steam into the distillation and steaming device for distillation. The steam mixes with the raw material for distillation, and the resulting alcohol vapor is the first alcohol vapor.

[0028] Step 2: Control the valve so that the first batch of liquor vapor is condensed by the first condenser and then enters the first batch of liquor tank;

[0029] Step 3: After the first distillation is completed, the resulting alcohol vapor is the main alcohol vapor. Control the valve so that the main alcohol vapor is condensed by the first condenser and then enters the main alcohol tank.

[0030] Step 4: After the main alcohol is distilled, the resulting alcohol vapor is called tail liquor vapor. A valve is controlled to allow this tail liquor vapor to enter the vapor permeation membrane module. The active ingredient vapor is obtained at the permeate side outlet of the vapor permeation membrane module. The valve is then controlled to allow this active ingredient vapor to be condensed by the first condenser and enter the active ingredient tank. The active ingredients in the tail liquor vapor permeate through the membrane to the permeate side, while off-flavor molecules are retained on the residual side. The obtained active ingredients in the tail liquor are suitable for further alcohol production or other industrial applications.

[0031] Preferably, the distillation temperature in step one is 80℃~120℃.

[0032] Preferably, the alcohol content of the first liquor is 68 degrees or higher, and the alcohol content of the main liquor is less than 68 degrees but more than 40 degrees.

[0033] Preferably, the operating temperature of the vapor permeation membrane module is 80℃~120℃.

[0034] The alcohol content of the final product in the active ingredient container is 45% to 50%.

[0035] The beneficial effects of this invention are as follows:

[0036] Existing technologies using pervaporation to separate active ingredients from the tail liquor require the addition of a microfiltration membrane before operation to remove organic impurities from the fermentation broth, resulting in high process costs. Furthermore, in pervaporation, the active ingredients in the tail liquor enter the membrane as liquid; therefore, the tail liquor vapor obtained from liquor production must first be condensed. The active ingredients preferentially dissolve on the membrane surface and, driven by the partial pressure difference across the membrane, diffuse at different rates to the downstream side before vaporizing. The vapor is then enriched after condensation to below zero degrees Celsius, leading to high energy consumption.

[0037] The distillation apparatus and process for baijiu (Chinese liquor) provided by this invention utilizes steam permeation technology. Compared to existing technologies, this invention uses clean steam to transfer mass through contact with a steam permeation membrane, preventing organic impurities from volatilizing and contaminating the membrane, and eliminating the need for a pre-microfiltration process. Simultaneously, the strong fluidity of the steam medium and gas-phase mass transfer can improve concentration polarization and swelling phenomena on the membrane surface, reducing membrane wear while ensuring separation efficiency, thereby lowering costs.

[0038] Furthermore, the process of this invention directly utilizes the steam from the wine distillation process to separate the liquid and vapor phases, reducing the energy consumption caused by the phase change. In addition, water is used as a heat exchange medium to condense the wine vapor during the condensation process to obtain liquid wine, which reduces the cost. The overall energy consumption is reduced by more than 45% compared to the pervaporation process. This process is simple and effective to operate, safe and environmentally friendly, low in energy consumption and low in cost, and suitable for industrial production. Attached Figure Description

[0039] Figure 1This is a schematic diagram of the distillation apparatus for baijiu (Chinese liquor) according to the present invention.

[0040] Among them, 1 is a steam pipe, 2 is a distillation and grain steaming device, 3 is a steam permeation membrane module, 4 and 5 are valves, 6 is the first condenser, 7 is the first wine tank, 8 is the main wine tank, 9 is the active ingredient tank, 10, 11 and 12 are valves, 13 is a vacuum device, and 14 is the second condenser. Detailed Implementation

[0041] Example 1

[0042] like Figure 1 The distillation apparatus for baijiu (Chinese liquor) shown includes a grain distillation device, a first condenser, and a vapor permeation membrane assembly. The inlet of the grain distillation device is connected to a steam pipe, and the outlet of the grain distillation device is connected to the first condenser and the vapor permeation membrane assembly respectively through valves. The vapor permeation membrane assembly includes a high-temperature resistant and solvent-resistant vapor permeation membrane, and the permeation-side outlet of the vapor permeation membrane assembly is connected to the first condenser.

[0043] The outlet of the first condenser is connected to the head wine tank, the main wine tank, and the active ingredient tank via valves.

[0044] The osmotic side outlet of the vapor permeation membrane module is connected to the tail wine tank via a second condenser.

[0045] The outlet of the distillation and steaming device is connected to the first condenser and the steam permeation membrane assembly via a three-way switching valve.

[0046] The outlet of the first condenser is connected to a vacuum device. The vacuum device provides the driving force for the vapor permeation operation.

[0047] The condensing medium in the first condenser is water.

[0048] The condensing medium in the second condenser is water.

[0049] The high-temperature resistant and solvent-resistant vapor permeation membrane is a composite membrane, which is prepared by the following steps:

[0050] (1) Pretreatment of PAN base film: Immerse the PAN base film in an alkaline solution to generate polar groups on the surface of the PAN base film; then heat treat to obtain a pretreated base film; the alkaline solution is a NaOH solution with a concentration of 0.3-1M; the heat treatment is as follows: after the PAN base film is unfolded, it is treated at 120-180℃ for 10-30 minutes, and then naturally cooled. This process is repeated 3 times.

[0051] (2) Preparation of deeply cross-linked precast film solution: After uniformly mixing the n-heptane solution of hydroxy vinyl silicone oil and tetraethoxysilane, tetrabutyltin is added as a catalyst and stirred until the viscosity of the mixture reaches 20 mPa·s to obtain the deeply cross-linked precast film solution.

[0052] (3) Preparation of casting solution: After uniformly mixing the pre-casting solution with hydrogen-containing silicone oil, add Caster PT5000-TMDVDS600 as a platinum-based catalyst and stir until the viscosity of the mixture reaches 30 mPa·s to complete the cross-linking and obtain the casting solution.

[0053] (4) Preparation of vapor permeation membrane: The casting solution obtained in step (4) is coated on the surface of the pretreated base membrane obtained in step (1), and crosslinked at 120-140℃ for 4-6 hours to obtain the high temperature resistant and solvent resistant vapor permeation organic membrane.

[0054] The PAN molecular weight of the PAN base film is 400,000 to 500,000.

[0055] In step (2), the mass ratio of hydroxyvinyl silicone oil to n-heptane in the n-heptane solution of hydroxyvinyl silicone oil is 6-12:88-94.

[0056] The mass ratio of the crosslinking agent to the hydroxyvinyl silicone oil solution in step (2) is 1-3:7-9.

[0057] The mass of the catalyst in step (2) is 0.01 to 1% of the mass of the hydroxyvinyl silicone oil solution.

[0058] The mass of the hydrogen-containing silicone oil in step (3) is 0.5 to 2% of the mass of the hydroxyvinyl silicone oil solution.

[0059] The mass of the platinum-based catalyst mentioned in step (3) is 0.1 to 0.3% of the hydrogen-containing silicone oil.

[0060] The coating thickness described in step (4) is 60–90 μm.

[0061] The above-mentioned baijiu distillation apparatus is used for baijiu distillation. Before operation, the raw materials for distillation are first put into the distillation and steaming device, and steam is introduced into the device for distillation at a temperature of 80℃~120℃. The steam mixes with the raw materials, and the resulting alcohol vapor is the first-run vapor, with an alcohol content of 68 degrees or higher. At this time, the valve is controlled so that the first-run vapor is condensed by the first condenser and enters the first-run tank. When the alcohol content in the steam reaches below 68 degrees but above 40 degrees, the first-run distillation is complete, and the resulting alcohol vapor is the main-run vapor. The valve is controlled so that the main-run vapor is condensed by the first condenser and enters the main-run tank. When the alcohol content in the steam reaches below 40 degrees, the main-run distillation is complete, and the resulting alcohol vapor is the tail-run vapor. The valve is controlled so that the tail-run vapor enters the vapor permeation membrane module, which operates at a temperature of 80℃~120℃. The effective component vapor is obtained at the permeate side outlet of the vapor permeation membrane module. The valve is controlled so that the effective component vapor is condensed by the first condenser and enters the effective component tank. The active ingredients in the tail liquor vapor permeate through the membrane to the permeate side, while off-flavor molecules are retained on the osmotic side. The active ingredients obtained from the tail liquor are suitable for further alcohol production or other industrial applications.

[0062] Producing one ton of 45-degree tail liquor requires energy consumption equivalent to 266 yuan.

[0063] In this embodiment, the changes in the substance content of the permeate-side product before and after treatment by the vapor permeation membrane module are shown in Table 1:

[0064] Table 1. Content of effective substances in a certain strong-aroma tail liquor (mg / 100mL)

[0065]

[0066]

[0067] Example 2 (Comparative Example)

[0068] Preferential treatment of organic matter through pervaporation membrane:

[0069] The tail liquor is first condensed in a condenser and then pumped into a raw material tank. A preheating device preheats the raw material to 30°C, allowing it to enter the upstream side of the membrane in liquid form. On the downstream side, a vacuum and condensation process creates a vapor pressure difference between the upstream and downstream components, allowing the active ingredients in the raw material to permeate through the membrane to the downstream side. Under vacuum conditions, the permeate vapor vapor is drawn into the condenser by a vacuum unit. After condensation, the purified liquor enters the product collection tank. It is estimated that producing 1 ton of 45-degree tail liquor requires energy equivalent to 770 RMB.

[0070] The technical solution in Example 1 requires only RMB 266 to produce 1 ton of 45-degree tail liquor. Compared with the above-mentioned solution that prioritizes the pervaporation membrane treatment of organic matter, the energy consumption is reduced by about 65.4%.

[0071] This invention replaces the pervaporation membrane method with a vapor permeation membrane method for processing tailings, saving energy in two areas: the phase change energy consumption of pervaporating liquid tailings into the membrane, and the need for -10°C cooling during vacuum condensation of pervaporation, which can be directly cooled with tap water. The energy savings for producing 1 ton of 45% ethanol tailings are equivalent to RMB 504. The process is as follows: the heat of vaporization of ethanol is approximately 841 kJ / kg, and the heat of vaporization of water is approximately 2260 kJ / kg. In 1 ton of 45% ethanol-water solution, the mass of ethanol is 450 kg, and the mass of water is 550 kg. The heat of vaporization of ethanol is 450 kg × 841 kJ / kg = 378450 kJ. The heat of vaporization of water is 550 kg × 2260 kJ / kg = 1243000 kJ. The total heat of vaporization is the sum of the heats of vaporization of ethanol and water, i.e., 378450 kJ + 1243000 kJ = 1621450 kJ. Therefore, converting 1 ton of 45% ethanol-water solution entirely into a gaseous state requires approximately 1621450 kJ of heat, equivalent to about 450.4 kWh. This calculation assumes no heat loss throughout the process and that the solution boils at atmospheric pressure. In practice, additional factors such as system thermal efficiency and environmental conditions may need to be considered. Assuming a refrigeration efficiency ratio of 2.5, to achieve a cooling capacity of 450.4 kWh, the refrigeration unit's energy consumption is approximately 180.16 kWh. This means that to provide 450.4 kWh of cooling energy, the refrigeration unit needs to consume 180.16 kWh of electrical energy. Therefore, using a vapor permeate membrane method instead of a pervaporation membrane method to treat the tailings saves approximately 630.56 kWh of total energy. Based on an industrial electricity price of 0.8 yuan per kilowatt-hour, the total cost of this process is approximately 504.45 yuan.

Claims

1. A distillation apparatus for white liquor, characterized by comprising: The distillation device is connected with a steam pipe at an inlet, and an outlet is connected with a first condenser and a steam permeation membrane assembly through valves respectively; the outlet of the first condenser is connected with a head wine tank, a main body wine tank and an effective component tank through valves respectively; the outlet of the steam permeation membrane assembly is connected with a tail wine tank through a second condenser, The steam permeation membrane assembly comprises a high-temperature-resistant and solvent-resistant steam permeation membrane, and the permeation side outlet of the steam permeation membrane assembly is connected with the first condenser; The high-temperature-resistant and solvent-resistant steam permeation membrane is a composite membrane prepared by the following steps: (1) PAN base film pretreatment: the PAN base film is immersed in an alkali solution to generate polar groups on the surface of the PAN base film; then, heat treatment is performed to obtain a pretreated base film; the alkali solution is a NaOH solution with a concentration of 0.3-1 M; the heat treatment is as follows: the PAN base film is unfolded and treated at 120-180 ℃ for 10-30 min, and then naturally cooled; the process is repeated for 3 times; (2) Preparation of a deeply crosslinked pre-casting membrane solution: the n-heptane solution of hydroxyvinyl silicone oil and tetraethoxysilane are uniformly mixed, then tetrabutyl tin is added as a catalyst, and stirring is performed until the viscosity of the mixed solution reaches 20 mPa·s, to obtain a deeply crosslinked pre-casting membrane solution; (3) Preparation of a casting membrane solution: the pre-casting membrane solution is uniformly mixed with hydrogen-containing silicone oil, then Castor PT5000-TMDVDS600 is added as a platinum-based catalyst, and stirring is performed until the viscosity of the mixed solution reaches 30 mPa·s, to complete staggered crosslinking, and obtain a casting membrane solution; (4) Preparation of a steam permeation membrane: the casting membrane solution obtained in step (3) is coated on the surface of the pretreated base film obtained in step (1), and crosslinking is performed at 120-140 ℃ for 4-6 h, to obtain the high-temperature-resistant and solvent-resistant steam permeation organic membrane.

2. The distillation apparatus for white spirits according to claim 1, characterized in that, The outlet of the distillation device is connected with the first condenser and the steam permeation membrane assembly through a three-way switching valve.

3. The distillation apparatus for white spirits according to claim 1, wherein The outlet of the first condenser is connected with a vacuum device.

4. The distillation apparatus for white spirits according to claim 1, wherein The mass of the catalyst in step (2) is 0.01-1% of the mass of the hydroxyvinyl silicone oil solution.

5. The distillation apparatus for white spirits according to claim 1, wherein The mass of the hydrogen-containing silicone oil in step (3) is 0.5-2% of the mass of the hydroxyvinyl silicone oil solution; the mass of the platinum-based catalyst is 0.1-0.3% of the mass of the hydrogen-containing silicone oil.

6. A distillation process of Baijiu using the Baijiu distillation device according to any one of claims 1-5, characterized in that, The method comprises the following steps: Step one: distillation raw materials are put into a distillation device, and steam is sent into the distillation device for distillation; the steam is mixed with the distillation raw materials, and the generated wine steam is head wine steam; Step two: the valves are controlled so that the head wine steam passes through the first condenser and is condensed into the head wine tank; Step three: after the head wine is distilled, the generated wine steam is main body wine steam, and the valves are controlled so that the main body wine steam passes through the first condenser and is condensed into the main body wine tank; Step four: after the main body liquor is distilled, the produced liquor steam is cocktail steam, the control valve is controlled to make the cocktail steam enter the steam permeation membrane assembly, the effective component steam is obtained at the permeation side outlet of the steam permeation membrane assembly, the control valve is controlled to make the effective component steam enter the effective component tank after being condensed by the first condenser, the effective components in the cocktail steam are permeated to the membrane permeation side through the membrane, and the impurity molecules are intercepted in the membrane retentate side, and the obtained effective components in the cocktail are suitable for further alcohol production or other industrial applications.

7. The distillation process of claim 6, wherein, The distillation temperature in step one is 80-120 DEG C. The operation temperature of the steam permeation membrane assembly is 80-120 DEG C.

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