A bio-cellulose production system and a method for producing bio-cellulose using the same

Abstract

The present application relates to a kind of biological cellulose production system and the method for producing biological cellulose with the system.The system includes fermentation unit, cleaning unit, cutting unit and purification unit.The present application makes full use of the adsorption performance of biological cellulose hydrogel itself, by the intermittent spraying of spray head, the up and down movement of fermentation chamber end face and the cooperation of conveying belt, multiple steps in the production of biological cellulose are formed into a complete pipeline, the continuous industrial production of biological cellulose hydrogel is realized, the production efficiency is greatly improved, and the production cost is reduced.

Description

Technical Field

[0001] This invention relates to a system and method for producing raw materials for bio-fermentation, and more particularly, to a system for producing bio-cellulose and a method for producing bio-cellulose using the system. Background Technology

[0002] Biological cellulose (also known as bacterial cellulose, BC) refers to cellulose produced by the fermentation of certain specific bacteria under different conditions. Biological cellulose shares the same molecular structural units as natural cellulose, but it also possesses many unique properties. First, compared to plant cellulose, it lacks byproducts such as lignin, pectin, and hemicellulose, exhibiting high crystallinity and high degree of polymerization. Second, it possesses an ultra-fine spatial network structure, consisting of fiber bundles composed of microfibers with a diameter of 3-4 nanometers, interwoven to form a well-developed ultra-fine network structure. Furthermore, it has an elastic modulus several times, even tens of times, greater than that of plant fibers, and also exhibits higher tensile strength. It also possesses strong water-holding capacity and good biocompatibility, adaptability, and biodegradability. Due to these advantages, biological cellulose materials have been widely used in various fields such as food, medicine, cosmetics, and biomaterials.

[0003] The production of bio-cellulose mainly involves cultivating bacteria such as *Acetobacter* to metabolize bio-cellulose. This includes static fermentation and dynamic fermentation. Static fermentation involves culturing bio-cellulose-producing bacteria in a static liquid culture medium, which forms a gel-like bio-cellulose gel product at the gas-liquid interface between the liquid medium and air. Dynamic fermentation, on the other hand, involves fermentation in a stirred or shaken flask to produce bio-cellulose. However, due to limitations in yield and product physicochemical properties, static fermentation is currently the primary method used to prepare bio-cellulose hydrogels.

[0004] Currently, the static fermentation equipment commonly used for bio-cellulose production is relatively simple, typically involving shallow trays filled with liquid culture medium, inoculated with microorganisms, and then fermentation. A major problem is that as a bio-cellulose hydrogel film forms on the surface of the culture medium during fermentation, it gradually isolates the oxygen necessary for the growth and reproduction of the bio-cellulose-producing bacteria. Therefore, once the bio-cellulose hydrogel reaches a certain thickness, the bacteria can no longer grow, significantly limiting the production efficiency of bio-cellulose. For example, CN107446796A discloses a bacterial cellulose fermentation production device, also for static fermentation, which improves production efficiency by setting up multiple culture boxes (similar to shallow trays) stacked on top of each other. However, this still does not fundamentally solve the oxygen supply problem, and its production efficiency and cost remain high. Furthermore, there is currently no highly automated, assembly-line production system applicable to bio-cellulose production, keeping bio-cellulose production at the workshop level, unable to handle large-scale production, which also contributes to the high production costs. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a biocellulose production system and a method for producing biocellulose using this system. It breaks away from the traditional technical route of using shallow-tray static fermentation culture for biocellulose and provides a highly automated, assembly-line processing system, which greatly improves the production efficiency of biocellulose and reduces production costs.

[0006] This invention provides a biocellulose production system, which includes a fermentation unit, a washing unit, a cutting unit, and a purification unit.

[0007] Specifically, the fermentation unit includes a fermentation chamber and a culture medium storage chamber. Both the fermentation chamber and the culture medium storage chamber are rectangular. The bottom surface of the fermentation chamber has a through-hole connecting to the culture medium storage chamber at one end away from the cleaning unit, and a through-groove connecting to the culture medium storage chamber at the other end. The remaining part of the bottom surface is formed by a conveyor belt, and a scraper is fixedly installed next to the conveyor belt near the cleaning unit. The end face of the fermentation chamber near the cleaning unit is made of a porous, rough material with good water absorption, and it can move up and down between the top plate of the fermentation chamber and the bottom plate of the culture medium storage chamber, passing through the aforementioned through-groove. The tip of the scraper abuts against the surface of the porous, rough material, scraping across its surface as the material moves up and down. A spray nozzle and a temperature control device are installed on the end face of the fermentation chamber away from the cleaning unit, and the spray nozzle is connected to the culture medium storage chamber via a pipeline. Except for the end face made of the porous, rough material, all other surfaces of the fermentation chamber and the culture medium storage chamber are made of insulating material. The cleaning unit mentioned above includes a conveyor belt and a spray system disposed above it; The cutting unit mentioned above includes: a conveyor belt and a set of cutters disposed thereon; The purification unit described therein includes a purification tank containing a purification solution.

[0008] Specifically, there are no particular limitations on the porous rough material with good water absorption, as long as it has good water absorption, can adsorb the culture medium to enable microorganisms to ferment and produce bio-cellulose hydrogel, and its roughness is sufficient for the bio-cellulose hydrogel to adsorb onto it. Examples of porous rough materials include ceramic materials or zeolite materials.

[0009] The porous rough material is fixed on the support plate and moves up and down by sliding in a groove set on the end face of the culture medium storage chamber near the cleaning unit. It can also be fixed with pins so that its upper end abuts against the top plate of the fermentation chamber to form the fermentation chamber.

[0010] Obviously, other methods that can fix and move porous, rough materials vertically are also acceptable, as long as they can move stably. The power for this vertical movement can be provided manually or through transmission devices such as electric motors, hydraulic rods, belts, and chains. Similarly, other methods can also be used to secure porous, rough materials. Any commonly known method in the art can be selected based on the method of vertical movement, and the specific method can be determined according to the setup cost and production scale.

[0011] The spray system described herein is not particularly limited, and the number of nozzles, spray intensity, etc. can be determined as needed.

[0012] The cutting blade assembly is not particularly limited and can be set according to the shape and size of the cut biocellulose gel. For example, setting an upright parallel blade assembly or a grid-like blade assembly can cut the biocellulose gel into strips of different sizes, and even rotating the blades can cut the strips into granules.

[0013] The purification tank is not particularly limited, as long as it can hold the cut bio-cellulose gel and soak it in the purification solution. A stirring and / or heating device may also be added as needed for purification.

[0014] The fermentation chamber of this invention is further provided with a covered culture medium inlet on its top plate. Through this inlet, the culture medium inoculated with microorganisms can enter the culture medium storage chamber through the fermentation chamber.

[0015] In this invention, a temperature control device is also installed on the inner wall of the culture medium storage chamber. This temperature control device can control the temperature inside the culture medium storage chamber, preventing fermentation of the liquid culture medium and maintaining its liquid state. Specifically, the temperature control devices in both the fermentation chamber and the culture medium storage chamber include heating and cooling devices. They can maintain a suitable fermentation temperature in the fermentation chamber and a non-fermenting, liquid temperature in the culture medium storage chamber under high or low temperatures, for example, maintaining the fermentation chamber at 25-30°C and the culture medium storage chamber at 5-15°C.

[0016] In this invention, a pump and a solenoid valve are also installed in the pipeline connecting the spray nozzle to control the intermittent spraying of the spray nozzle. Obviously, continuous spraying of the spray nozzle does not affect the fermentation process, but for energy-saving considerations, intermittent spraying is preferred.

[0017] The present invention also provides a method for producing biocellulose using the biocellulose production system described herein, comprising the following steps: Lower the end face of the fermentation chamber, which is made of a porous, rough material with good water absorption, so that it passes through the channel and reaches the bottom plate of the culture medium storage chamber; A culture medium is prepared by inoculating bio-cellulose-producing bacteria into a sterilized liquid culture medium. The culture medium is then poured into the fermentation chamber through the culture medium inlet and flows into the culture medium storage chamber through the gaps in the through holes and channels. The end face of the fermentation chamber, made of a porous rough material with good water absorption, is raised and passed through the channel to the top plate of the fermentation chamber to form the fermentation chamber, and the culture medium is adsorbed on the porous rough material. Fermentation is carried out until a thin layer of bio-cellulose gel grows on the surface of the porous, rough material. The culture medium is then transported from the culture medium storage chamber to the spray nozzle through a pipeline. The culture medium is then sprayed onto the surface of the bio-cellulose gel thin layer through the spray nozzle, and fermentation continues. As the thickness increases, the steps of spraying culture medium and fermentation are repeated until the bio-cellulose gel grows to the required thickness. Excess culture medium sprayed out flows back to the culture medium storage chamber through the gaps in the through holes and grooves. After fermentation, the end face of the fermentation chamber, made of a porous rough material with good water absorption, is lowered so that it passes through the channel and reaches the bottom plate of the culture medium storage chamber. At the same time, the bio-cellulose gel is separated from the porous rough material by a scraper. The conveyor belt is started to send the bio-cellulose gel to the cleaning unit. The spray system in the cleaning unit is turned on for cleaning. After cleaning, the bio-cellulose gel is continued to be conveyed by the conveyor belt and passed through the cutter group set on the conveyor belt in the cutting unit to cut it into the required shape. The cut bio-cellulose gel is then conveyed by the conveyor belt to the purification unit and falls into the purification tank containing the purification solution. After stirring and purification, it is harvested.

[0018] In the method for producing biocellulose of the present invention, the spraying system in the washing unit sprays deionized water; the purification solution in the purification tank of the purification unit is an alkaline solution, such as sodium hydroxide solution.

[0019] In the method for producing biocellulose of the present invention, the temperature in the fermentation chamber is controlled at 25-30°C; the temperature in the culture medium storage chamber is controlled at 5-15°C below the fermentation temperature.

[0020] It is easy to understand that, for the purpose of easy monitoring, monitoring equipment such as thermometers, hygrometers and their sensors can be installed in the fermentation room and culture medium storage room as needed.

[0021] This invention breaks away from the traditional shallow-pan fermentation method commonly used in static fermentation. It utilizes the adsorption properties of the bio-cellulose hydrogel itself and controls the temperature of the fermentation chamber and the culture medium storage chamber separately. It sets up a complete production line for fermentation, washing, cutting and purification in bio-cellulose production, realizing the continuous industrial production of bio-cellulose hydrogel, which can greatly improve production efficiency and significantly reduce production costs. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the bio-cellulose production system of the present invention; wherein: 1-fermentation unit; 2-washing unit; 3-cutting unit; 4-purification unit; 5-fermentation chamber; 6-culture medium storage chamber; 7-through hole; 8-through groove; 9-scraper; 10-porous rough material; 11-spray nozzle; 12-temperature control device; 13-support plate; 14-pin; 15-spraying system; 16-cutting assembly; 17-purification tank; 18-culture medium inlet; 19-bio-cellulose gel. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it is readily understood that the specific embodiments described below are merely illustrative examples of the invention and should not be construed as limiting the invention. Any modifications or adjustments that do not depart from the scope of the invention are within the scope of the invention. Example 1:

[0024] According to the appendix of this invention Figure 1 The structure shown provides a biocellulose production system for this embodiment, wherein the porous rough material is made of zeolite; there are two spray nozzles, and the air temperature is 22°C.

[0025] First, lower the zeolite material end face 10 of fermentation chamber 5 so that it passes through the through groove 8 and reaches the bottom plate of culture medium storage chamber 6. Then, inoculate bio-cellulose-producing bacteria into sterilized liquid culture medium to prepare culture medium, and pour the culture medium into fermentation chamber 5 through culture medium inlet 18. Then, it flows into culture medium storage chamber 6 through the gaps in through hole 7 and through groove 8. Turn on the temperature control device 12 in culture medium storage chamber 6 to control the temperature of culture medium storage chamber to 15°C. Next, raise the zeolite material end face 10 of fermentation chamber so that it passes through the through groove 8 and reaches the top plate of fermentation chamber 5, forming fermentation chamber. The culture medium is adsorbed on the zeolite material end face 10. Turn on the temperature control device 12 in fermentation chamber to set the temperature in fermentation chamber to 28°C for fermentation. When a thin layer of bio-cellulose gel 19 grows on the surface of zeolite material end face 10, transport the culture medium from culture medium storage chamber 6 to spray nozzle 11 through pipeline, and then spray the culture medium onto the surface of fermentation chamber 6. Fermentation is carried out on the surface of the thin layer of bio-cellulose gel. As its thickness increases, the steps of spraying culture medium and fermentation are repeated until the bio-cellulose gel 19 grows to the required thickness. The excess culture medium sprayed out flows back to the culture medium storage chamber 6 through the gaps of the through hole 7 and the through groove 8. After fermentation, the end face 10 of the zeolite material is lowered so that it passes through the through groove 8 and reaches the bottom plate of the culture medium storage chamber 6. At the same time, the bio-cellulose gel 19 is separated from the zeolite material by the scraper 9. The conveyor belt is started to send the bio-cellulose gel 19 to the cleaning unit 2. The spray system 15 in the cleaning unit is turned on to spray deionized water for cleaning. After cleaning for 10 minutes, the bio-cellulose gel 19 is continued to be transported by the conveyor belt and cut into small strips by the cutter group 16 set on the conveyor belt in the cutting unit 3. Then it is transported to the purification unit 4 and falls into the purification tank 17 containing 1% sodium hydroxide solution. After stirring and purification, it is harvested. Example 2:

[0026] According to the appendix of this invention Figure 1 The structure shown provides a biocellulose production system for this embodiment, wherein the porous rough material is made of ceramic material; there are two spray nozzles, and the air temperature is 12°C.

[0027] First, lower the ceramic material end face 10 of fermentation chamber 5 so that it passes through the through groove 8 and reaches the bottom plate of culture medium storage chamber 6. Then, inoculate bio-cellulose-producing bacteria into sterilized liquid culture medium to prepare culture medium, and pour the culture medium into fermentation chamber 5 through culture medium inlet 18. Then, it flows into culture medium storage chamber 6 through the gaps in through hole 7 and through groove 8. There is no need to turn on the temperature control device 12 in culture medium storage chamber 6; the temperature of culture medium storage chamber 6 can be maintained at 12°C. Next, raise the ceramic material end face 10 of fermentation chamber 5 so that it passes through the through groove 8 and reaches the top plate of fermentation chamber 5, forming fermentation chamber. The culture medium is adsorbed on the ceramic material end face 10. Turn on the temperature control device 12 in fermentation chamber 6 to maintain the temperature of fermentation chamber 6 at 26°C for fermentation. When a thin layer of bio-cellulose gel 19 grows on the surface of ceramic material end face 10, transport the culture medium from culture medium storage chamber 6 to spray nozzle 11 through pipeline, and then spray the culture medium onto the fermentation chamber 6. Fermentation is carried out on the surface of the thin layer of biocellulose gel. When its thickness increases, the steps of spraying culture medium and fermentation are repeated until the biocellulose gel 19 grows to the required thickness. The excess culture medium sprayed out flows back to the culture medium storage chamber 6 through the gap between the through hole 7 and the through groove 8. After fermentation, the end face 10 of the ceramic material is lowered so that it passes through the through groove 8 and reaches the bottom plate of the culture medium storage chamber 6. At the same time, the biocellulose gel 19 is separated from the ceramic material by the scraper 9. The conveyor belt is started to send the biocellulose gel 19 to the cleaning unit 2. The spray system 15 in the cleaning unit is turned on to spray deionized water for cleaning. After cleaning for 12 minutes, the biocellulose gel 19 is continued to be transported by the conveyor belt and cut into granules by the cutter group 16 set on the conveyor belt in the cutting unit 3. Then it is transported to the purification unit 4 and falls into the purification tank 17 containing 1% sodium hydroxide solution. After heating to 35°C and stirring to complete the purification, it is harvested.

[0028] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A biocellulose production system, characterized in that: It includes a fermentation unit (1), a washing unit (2), a cutting unit (3), and a purification unit (4); The fermentation unit (1) includes a fermentation chamber (5) and a culture medium storage chamber (6); both the fermentation chamber (5) and the culture medium storage chamber (6) are rectangular parallelepipeds. The bottom surface of the fermentation chamber (5) has a through hole (7) connecting to the culture medium storage chamber (6) at one end away from the cleaning unit (2), and a through groove (8) connecting to the culture medium storage chamber (6) at the other end. The rest of the bottom surface is formed by a conveyor belt, and a scraper (9) is fixedly installed next to the conveyor belt in the direction close to the cleaning unit (2). The end face of the fermentation chamber (5) near the cleaning unit (2) is made of a porous, rough material (10) with good water absorption, and it can be used in the fermentation chamber. The top plate of (5) moves up and down through the above-mentioned through groove (8) between the bottom plate of the culture medium storage chamber (6); the tip of the scraper (9) abuts against the surface of the porous rough material (10), so that when the porous rough material (10) moves up and down, the scraper (9) scrapes across its surface; a spray nozzle (11) and a temperature control device (12) are provided on the end face of the fermentation chamber (5) away from the cleaning unit (2), and the spray nozzle (11) is connected to the culture medium storage chamber (6) through a pipeline; the other surfaces of the fermentation chamber (5) and the culture medium storage chamber (6) except for the end face made of porous rough material (10) are all made of heat-insulating material; The cleaning unit (2) mentioned therein includes: a conveyor belt and a spray system (15) disposed above it; The cutting unit (3) mentioned therein includes: a conveyor belt and a set of cutters (16) disposed thereon; The purification unit (4) therein includes a purification tank (17) containing a purification solution.

2. The biocellulose production system according to claim 1, characterized in that: The porous, rough material with good water absorption is a ceramic material or a zeolite material.

3. The biocellulose production system according to claim 2, characterized in that: The porous rough material (10) is fixed on the support plate (13) and moves up and down by sliding the support plate (13) in the groove set on the end face of the culture medium storage chamber (6) near the cleaning unit (2). It can be fixed by pins (14) so ​​that its upper end abuts against the top plate of the fermentation chamber to form the fermentation chamber.

4. The biocellulose production system according to any one of claims 1-3, characterized in that: The fermentation chamber (5) is also equipped with a covered culture medium inlet (18) on the top plate.

5. The biocellulose production system according to any one of claims 1-3, characterized in that: A temperature control device (12) is also installed on the inner wall of the culture medium storage chamber (6).

6. The biocellulose production system according to claim 5, characterized in that: The temperature control devices (12) in the fermentation chamber (5) and the culture medium storage chamber (6) both include heating devices and cooling devices.

7. The biocellulose production system according to any one of claims 1-3, characterized in that: A pump and a solenoid valve are also installed in the pipeline connecting the spray nozzle (11) to control the intermittent spraying of the spray nozzle (11).

8. A method for producing biocellulose using the biocellulose production system according to any one of claims 1-7, characterized in that: Includes the following steps: 1) Lower the end face of the fermentation chamber made of porous rough material (10) with good water absorption so that it passes through the through groove (8) and reaches the bottom plate of the culture medium storage chamber (6); 2) Inoculate the sterilized liquid culture medium with bio-cellulose-producing bacteria to make a culture solution. Pour the culture solution into the fermentation chamber (5) through the culture solution inlet (18) and flow into the culture solution storage chamber (6) through the gaps of the through hole (7) and through groove (8). 3) Raise the end face of the fermentation chamber made of porous rough material (10) with good water absorption, so that it passes through the through groove (8) and reaches the top plate of the fermentation chamber (5) to form a fermentation chamber, and the culture medium is adsorbed on the porous rough material (10); 4) Fermentation is carried out. When a thin layer of bio-cellulose gel (19) grows on the surface of the porous rough material (10), the culture solution is transported from the culture solution storage chamber (6) to the spray nozzle (11) through the pipeline. The culture solution is then sprayed onto the surface of the bio-cellulose gel thin layer through the spray nozzle (11) and fermentation is carried out. When the thickness increases, the steps of spraying culture solution and fermentation are repeated until the bio-cellulose gel (19) grows to the required thickness. The excess culture solution sprayed out flows back to the culture solution storage chamber (6) through the gaps of the through hole (7) and the through groove (8). 5) After fermentation, the end face of the fermentation chamber made of porous rough material (10) with good water absorption is lowered so that it passes through the through groove (8) and reaches the bottom plate of the culture medium storage chamber (6). At the same time, the bio-cellulose gel (19) is separated from the porous rough material (10) by scraper (9). 6) Start the conveyor belt and send the bio-cellulose gel (19) to the cleaning unit (2). Turn on the spray system (15) in the cleaning unit to clean it. After cleaning, continue to transport the bio-cellulose gel (19) through the conveyor belt so that it passes through the cutter group (16) set on the conveyor belt in the cutting unit (3) to cut it into the required shape. Continue to transport the cut bio-cellulose gel to the purification unit (4) through the conveyor belt and drop it into the purification pool (17) containing the purification solution. After stirring and completing the purification, harvest it.

9. The method for producing bio-cellulose according to claim 8, characterized in that: The spray system (15) in the cleaning unit (2) sprays deionized water; the purification solution in the purification tank (17) in the purification unit (4) is an alkaline solution.

10. The method for producing bio-cellulose according to claim 9, characterized in that: The temperature in the fermentation chamber (5) is controlled at 25-30℃; the temperature in the culture medium storage chamber (6) is controlled at 5-15℃ lower than the fermentation temperature.

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