CN112481107A - System and process for preparing lactic acid by starch fermentation - Google Patents
System and process for preparing lactic acid by starch fermentation Download PDFInfo
- Publication number
- CN112481107A CN112481107A CN201910860707.2A CN201910860707A CN112481107A CN 112481107 A CN112481107 A CN 112481107A CN 201910860707 A CN201910860707 A CN 201910860707A CN 112481107 A CN112481107 A CN 112481107A
- Authority
- CN
- China
- Prior art keywords
- fermentation
- fermentation tank
- micro
- tank
- lactic acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 238000000855 fermentation Methods 0.000 title claims abstract description 282
- 230000004151 fermentation Effects 0.000 title claims abstract description 282
- JVTAAEKCZFNVCJ-UHFFFAOYSA-N lactic acid Chemical compound CC(O)C(O)=O JVTAAEKCZFNVCJ-UHFFFAOYSA-N 0.000 title claims abstract description 164
- 239000004310 lactic acid Substances 0.000 title claims abstract description 81
- 235000014655 lactic acid Nutrition 0.000 title claims abstract description 81
- 229920002472 Starch Polymers 0.000 title claims abstract description 68
- 239000008107 starch Substances 0.000 title claims abstract description 68
- 235000019698 starch Nutrition 0.000 title claims abstract description 68
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 12
- 239000000463 material Substances 0.000 claims abstract description 186
- 239000007788 liquid Substances 0.000 claims abstract description 59
- 241000894006 Bacteria Species 0.000 claims abstract description 48
- 239000000839 emulsion Substances 0.000 claims abstract description 25
- 238000002156 mixing Methods 0.000 claims abstract description 10
- 238000012546 transfer Methods 0.000 claims abstract description 9
- 238000000926 separation method Methods 0.000 claims description 62
- 238000005842 biochemical reaction Methods 0.000 claims description 61
- 238000006243 chemical reaction Methods 0.000 claims description 25
- 239000002994 raw material Substances 0.000 claims description 21
- 238000010992 reflux Methods 0.000 claims description 6
- 238000007599 discharging Methods 0.000 claims description 5
- 238000001914 filtration Methods 0.000 claims description 5
- 230000001580 bacterial effect Effects 0.000 claims description 4
- 238000011068 loading method Methods 0.000 claims description 2
- 239000002245 particle Substances 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 14
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 5
- 239000006227 byproduct Substances 0.000 abstract description 5
- 239000001301 oxygen Substances 0.000 abstract description 5
- 229910052760 oxygen Inorganic materials 0.000 abstract description 5
- 238000005728 strengthening Methods 0.000 abstract description 3
- 230000000694 effects Effects 0.000 abstract description 2
- 230000005501 phase interface Effects 0.000 abstract description 2
- 229960000448 lactic acid Drugs 0.000 description 62
- 239000007789 gas Substances 0.000 description 42
- 239000012071 phase Substances 0.000 description 28
- JVTAAEKCZFNVCJ-REOHCLBHSA-N L-lactic acid Chemical compound C[C@H](O)C(O)=O JVTAAEKCZFNVCJ-REOHCLBHSA-N 0.000 description 10
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 8
- 230000008569 process Effects 0.000 description 8
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 6
- 238000005192 partition Methods 0.000 description 6
- 229910000019 calcium carbonate Inorganic materials 0.000 description 4
- 238000001514 detection method Methods 0.000 description 4
- 239000012530 fluid Substances 0.000 description 4
- 235000013305 food Nutrition 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 229920001592 potato starch Polymers 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 239000003814 drug Substances 0.000 description 3
- 239000002105 nanoparticle Substances 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 229930182843 D-Lactic acid Natural products 0.000 description 2
- JVTAAEKCZFNVCJ-UWTATZPHSA-N D-lactic acid Chemical compound C[C@@H](O)C(O)=O JVTAAEKCZFNVCJ-UWTATZPHSA-N 0.000 description 2
- -1 L-lactic acid Chemical compound 0.000 description 2
- 241000208125 Nicotiana Species 0.000 description 2
- 235000002637 Nicotiana tabacum Nutrition 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 238000005273 aeration Methods 0.000 description 2
- 235000008429 bread Nutrition 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 239000002537 cosmetic Substances 0.000 description 2
- 229940022769 d- lactic acid Drugs 0.000 description 2
- 239000000645 desinfectant Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- LZCLXQDLBQLTDK-UHFFFAOYSA-N ethyl 2-hydroxypropanoate Chemical compound CCOC(=O)C(C)O LZCLXQDLBQLTDK-UHFFFAOYSA-N 0.000 description 2
- 230000036541 health Effects 0.000 description 2
- 238000011081 inoculation Methods 0.000 description 2
- 239000002054 inoculum Substances 0.000 description 2
- 239000007791 liquid phase Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 150000007524 organic acids Chemical class 0.000 description 2
- NGSFWBMYFKHRBD-DKWTVANSSA-M sodium;(2s)-2-hydroxypropanoate Chemical compound [Na+].C[C@H](O)C([O-])=O NGSFWBMYFKHRBD-DKWTVANSSA-M 0.000 description 2
- 239000007790 solid phase Substances 0.000 description 2
- 241000894007 species Species 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- KDYFGRWQOYBRFD-UHFFFAOYSA-N succinic acid Chemical compound OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 description 2
- 238000009423 ventilation Methods 0.000 description 2
- CYDQOEWLBCCFJZ-UHFFFAOYSA-N 4-(4-fluorophenyl)oxane-4-carboxylic acid Chemical compound C=1C=C(F)C=CC=1C1(C(=O)O)CCOCC1 CYDQOEWLBCCFJZ-UHFFFAOYSA-N 0.000 description 1
- 208000010444 Acidosis Diseases 0.000 description 1
- 239000002028 Biomass Substances 0.000 description 1
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 description 1
- 102000004190 Enzymes Human genes 0.000 description 1
- 108090000790 Enzymes Proteins 0.000 description 1
- 229910001111 Fine metal Inorganic materials 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 208000002682 Hyperkalemia Diseases 0.000 description 1
- 229930182555 Penicillin Natural products 0.000 description 1
- JGSARLDLIJGVTE-MBNYWOFBSA-N Penicillin G Chemical compound N([C@H]1[C@H]2SC([C@@H](N2C1=O)C(O)=O)(C)C)C(=O)CC1=CC=CC=C1 JGSARLDLIJGVTE-MBNYWOFBSA-N 0.000 description 1
- QMGGUIASDZZMHS-UHFFFAOYSA-N Stearoyllactic acid Chemical compound CCCCCCCCCCCCCCCCCC(=O)OC(C)C(O)=O QMGGUIASDZZMHS-UHFFFAOYSA-N 0.000 description 1
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 1
- 230000007950 acidosis Effects 0.000 description 1
- 208000026545 acidosis disease Diseases 0.000 description 1
- 238000010564 aerobic fermentation Methods 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 150000001413 amino acids Chemical class 0.000 description 1
- 230000000844 anti-bacterial effect Effects 0.000 description 1
- 235000013405 beer Nutrition 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- MKJXYGKVIBWPFZ-UHFFFAOYSA-L calcium lactate Chemical compound [Ca+2].CC(O)C([O-])=O.CC(O)C([O-])=O MKJXYGKVIBWPFZ-UHFFFAOYSA-L 0.000 description 1
- 239000001527 calcium lactate Substances 0.000 description 1
- 229960002401 calcium lactate Drugs 0.000 description 1
- 235000011086 calcium lactate Nutrition 0.000 description 1
- MKJXYGKVIBWPFZ-CEOVSRFSSA-L calcium;(2s)-2-hydroxypropanoate Chemical compound [Ca+2].C[C@H](O)C([O-])=O.C[C@H](O)C([O-])=O MKJXYGKVIBWPFZ-CEOVSRFSSA-L 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 235000019504 cigarettes Nutrition 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 239000003995 emulsifying agent Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 229940116333 ethyl lactate Drugs 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 235000013373 food additive Nutrition 0.000 description 1
- 239000002778 food additive Substances 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- 229940093915 gynecological organic acid Drugs 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000001802 infusion Methods 0.000 description 1
- 239000010985 leather Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000004530 micro-emulsion Substances 0.000 description 1
- 230000000813 microbial effect Effects 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 229940049954 penicillin Drugs 0.000 description 1
- 239000003755 preservative agent Substances 0.000 description 1
- 230000002335 preservative effect Effects 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000036632 reaction speed Effects 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000001540 sodium lactate Substances 0.000 description 1
- 229940005581 sodium lactate Drugs 0.000 description 1
- 235000011088 sodium lactate Nutrition 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 239000001384 succinic acid Substances 0.000 description 1
- 239000011975 tartaric acid Substances 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M23/00—Constructional details, e.g. recesses, hinges
- C12M23/34—Internal compartments or partitions
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M33/00—Means for introduction, transport, positioning, extraction, harvesting, peeling or sampling of biological material in or from the apparatus
- C12M33/04—Means for introduction, transport, positioning, extraction, harvesting, peeling or sampling of biological material in or from the apparatus by injection or suction, e.g. using pipettes, syringes, needles
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M41/00—Means for regulation, monitoring, measurement or control, e.g. flow regulation
- C12M41/12—Means for regulation, monitoring, measurement or control, e.g. flow regulation of temperature
- C12M41/18—Heat exchange systems, e.g. heat jackets or outer envelopes
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M41/00—Means for regulation, monitoring, measurement or control, e.g. flow regulation
- C12M41/26—Means for regulation, monitoring, measurement or control, e.g. flow regulation of pH
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
- C12P7/00—Preparation of oxygen-containing organic compounds
- C12P7/40—Preparation of oxygen-containing organic compounds containing a carboxyl group including Peroxycarboxylic acids
- C12P7/56—Lactic acid
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Wood Science & Technology (AREA)
- Engineering & Computer Science (AREA)
- Zoology (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Biochemistry (AREA)
- Microbiology (AREA)
- Biotechnology (AREA)
- General Engineering & Computer Science (AREA)
- General Health & Medical Sciences (AREA)
- Genetics & Genomics (AREA)
- Sustainable Development (AREA)
- Biomedical Technology (AREA)
- Analytical Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Clinical Laboratory Science (AREA)
- Molecular Biology (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Apparatus Associated With Microorganisms And Enzymes (AREA)
- Preparation Of Compounds By Using Micro-Organisms (AREA)
Abstract
The invention relates to a system and a process for preparing lactic acid by starch fermentation, which comprises the following steps: fermentation cylinder, knockout drum, at least two micro-interface generators and back flow. Compared with the traditional method, the method has the advantages that the air is crushed to form micron-sized bubbles with micron scale, and the micron-sized bubbles are mixed with the starch solution to form gas-liquid emulsion, so that the phase interface area of gas-liquid two phases is increased, and the effect of strengthening mass transfer within a lower preset operation condition range is achieved; meanwhile, the micron-sized bubbles can be fully mixed with the starch solution to form a gas-liquid emulsion, and the gas-liquid two-phase full mixing can ensure that lactic acid producing bacteria in the system can fully absorb oxygen in the material, so that byproducts are prevented from being generated, and the fermentation efficiency of the system is further improved.
Description
Technical Field
The invention relates to the technical field of bacterial fermentation, in particular to a system and a process for preparing lactic acid by starch fermentation.
Background
Lactic acid is one of three major organic acids (including lactic acid, citric acid and acetic acid), is an organic acid prepared by using starch as a raw material and performing microbial fermentation and refining, and is widely applied to the fields of food, medicine, chemical industry and the like.
In the field of food industry, lactic acid is widely used as an acidulant and a preservative in the food industry because it is soft and stable in acidity, and therefore, the consumption amount of lactic acid in the food industry accounts for about 60% of the total consumption amount of lactic acid in the world. Since the human body only has enzymes for metabolizing L-lactic acid, D-lactic acid cannot be absorbed by the human body, and excessive use of D-lactic acid is toxic to the human body. Therefore, the world health organization advocates that L-lactic acid is used as a food additive and an internal medicine to replace DL-lactic acid which is generally used at present. Meanwhile, the use of phosphoric acid to adjust the pH of wort has been banned in the field of beer production, but L-lactic acid has been used as an adjusting agent. It has been investigated that one fourth of the world's lactic acid is used to produce stearoyllactic acid, while its salts are used in large quantities for bread production due to the longer shelf life of bread. In addition, the lactic acid is added into the tobacco, so that the humidity of the tobacco can be kept, and the quality of the cigarette can be improved.
In the field of pharmaceutical industry, lactic acid, particularly L-lactic acid, has a strong bactericidal effect, even higher than that of common disinfectants such as citric acid, tartaric acid, succinic acid and the like, and can be used as a disinfectant in places such as operating rooms, wards, laboratories, workshops and the like. Research shows that the infusion compounded with L-lactic acid, sodium L-lactate, glucose, amino acid, etc. can treat acidosis and hyperkalemia, and L-ferric lactate, sodium L-lactate and calcium L-lactate are excellent medicine for replenishing metal elements.
In the fields of chemical industry and the like, lactic acid is used as a deliming agent in the leather industry and also for treating textile fibres to make them easily tintable, to increase gloss and to make them soft to the touch. Ethyl lactate as a "green solvent" can be used as a fine metal cleaner in the electronics, aerospace, and semiconductor industries. In cosmetics, lactic acid, sodium lactate and calcium lactate can provide moisture-keeping property, and phthalyl zirconium lactate is effective emulsifier, material filler and stabilizer in cosmetics and health products, and can improve skin structure, prevent aging, and protect skin.
Chinese patent publication No.: CN106244638A discloses a comprehensive utilization process for producing lactic acid by biomass circulating fermentation. Based on the existing lactic acid production process of saccharifying and fermenting simultaneously, the method is combined with the pretreatment method of lactic acid fermentation thallus residues to realize the recycling of thallus. It can be seen that the process suffers from the following problems:
firstly, in the crushing step in the process, air forms large bubbles after being crushed, but the bubbles cannot be fully mixed with the mixed materials due to overlarge volume, so that oxygen is not uniformly absorbed by bacteria, and the fermentation efficiency of the system is reduced.
Secondly, the device is easy to produce by-products under the condition that bacteria are not uniformly contacted with oxygen, so that materials in the system cannot be used, and the energy consumption of the system is increased.
Disclosure of Invention
Therefore, the invention provides a system and a process for preparing lactic acid by starch fermentation, which are used for solving the problem of low fermentation efficiency caused by the production of byproducts because the penicillin producing bacteria are not completely fermented because sterile air cannot be fully mixed with fermentation raw materials in the prior art.
In one aspect, the present invention provides a system for producing lactic acid by fermentation of starch, comprising:
a fermentor for fermenting a material with lactic acid producing bacteria, the fermentor comprising: a complete mixed flow biochemical reaction area which is arranged below and used for loading starch solution and lactic acid producing bacteria and providing reaction space for the fermentation of the starch solution and the lactic acid producing bacteria, and a plug flow biochemical reaction area which is arranged above and used for conveying fermented materials and separating gas from liquid;
the separation tank is connected with the fermentation tank and is used for separating the materials output by the fermentation tank to generate gaseous strains and fermentation liquor;
at least two micro-interface generators which are respectively arranged at the appointed positions in the fully mixed flow reaction zone, convert the pressure energy of gas and/or the kinetic energy of liquid into the surface energy of bubbles and transmit the surface energy to the sterile air, so that the sterile air is crushed into micron-sized bubbles with the diameter of more than or equal to 1 mu m and less than 1mm to improve the mass transfer area between the starch solution and the sterile air, reduce the thickness of a liquid film and reduce the mass transfer resistance, and the starch solution and the micron-sized bubbles are mixed to form a gas-liquid emulsion after being crushed, so as to strengthen the mass transfer efficiency between the starch solution and the sterile air within the range of preset operation conditions;
and the return pipes are respectively connected with the fermentation tank and the separation tank and used for exchanging heat of the materials output by the fermentation tank and shunting the materials after heat exchange so as to respectively return to the fermentation tank or output to the separation tank.
Further, the micro-interface generator includes:
the first micro-interface generator is a pneumatic micro-interface generator, is arranged in the complete mixed flow biochemical reaction zone and is positioned at the bottom of the reaction zone, and is used for crushing sterile air to form micron-scale bubbles and outputting the micron-scale bubbles to the fermentation tank after the crushing is finished;
and the second micro-interface generator is an air-liquid linkage type micro-interface generator, is arranged in the full-mixed flow biochemical reaction area and is positioned at the top of the reaction area, is used for receiving the material output by the return pipe, uses the material to crush the sterile air to form micron-scale micron-sized bubbles, and mixes the micron-scale bubbles with the material to form an air-liquid emulsion to be output to the full-mixed flow biochemical reaction area.
Further, the complete mixed flow biochemical reaction area in the fermentation tank comprises:
the grating is arranged inside the fermentation tank and is used for filtering insoluble particles in the material;
the pH adjusting liquid feeding port is arranged on the side wall of the fermentation tank, is positioned above the grating and is used for conveying pH adjusting liquid to adjust the pH value of the material;
the fermentation raw material feeding hole is formed in the side wall of the fermentation tank, is positioned below the grating and is used for conveying starch solution;
the fermentation strain feeding hole is formed in the side wall of the fermentation tank and is positioned below the fermentation raw material feeding hole, and is used for conveying lactic acid producing bacteria to the interior of the fermentation tank and fermenting starch solution;
a first gaseous feed conduit disposed in a side wall of the fermentor and connected to the micro-interface generator for lateral delivery of sterile air into the micro-interface generator within the fermentor;
a residue outlet arranged at the bottom of the fermentation tank and used for discharging fermented residue out of the system;
the baffle, it set up in fermentation cylinder inner wall is located the grid below for block the starch of fermentation raw materials feed inlet output with the fluctuation that lactic acid producing bacteria produced of fermentation bacterial feed inlet output.
Further, the plug flow reaction zone comprises:
the exhaust pipeline is arranged at the top end of the fermentation tank and used for exhausting tail gas generated in the fermentation of the materials in the fermentation tank;
the second gas-phase feeding pipeline is arranged at the top end of the fermentation tank, is connected with the micro-interface generator and is used for conveying the tail gas generated at the top of the fermentation tank into the micro-interface generator in the fermentation tank;
the discharge port is arranged on the side wall of the fermentation tank and used for outputting the fermented materials out of the fermentation tank;
and the backflow feeding pipeline is arranged on the side wall of the fermentation tank and used for outputting part of materials output by the backflow pipe to the micro-interface generator in the fermentation tank.
Further, the return pipe includes:
the circulating pump is connected with the fermentation tank and used for outputting materials fermented in the fermentation tank;
and the heat exchanger is connected with the circulating pump and used for exchanging heat of the material output by the circulating pump so as to enable the material to reach the specified temperature.
Furthermore, the output end of the heat exchanger is provided with a shunt tube, and the shunt tube is respectively connected with the fermentation tank and the separation tank and used for respectively refluxing the materials and outputting the materials to the separation tank.
Further, the separation tank is a sealed tank, and comprises:
the feeding hole is arranged at the top end of the separation tank and used for conveying the material output by the return pipe to the inside of the separation tank;
the exhaust port is arranged at the top end of the separation tank and used for outputting gaseous strains;
and the discharge port is arranged at the bottom end of the separation tank and used for outputting the separated fermentation liquor and conveying the fermentation liquor to the next working section.
In another aspect, the present invention provides a process for preparing lactic acid by starch fermentation, comprising:
step 1: conveying the starch solution of the specified type to a complete mixed flow biochemical reaction area in the fermentation tank through the fermentation raw material feeding hole, and conveying the lactic acid producing bacteria to the fermentation tank through the fermentation strain feeding hole;
step 2: conveying sterile air to the first micro-interface generator through the first gas-phase feeding pipeline, crushing the sterile air into micron-sized bubbles by the first micro-interface generator, outputting the micron-sized bubbles into a starch solution in the fermentation tank, and sufficiently mixing the micron-sized bubbles with the starch solution to provide an aerobic environment for lactic acid producing bacteria;
and step 3: the lactic acid producing bacteria and the starch solution react in an aerobic environment, after fermentation is completed, the fermentation tank conveys the fermented material to the plug flow biochemical reaction area, the material flows through the grating, the grating can filter residues in the material, and the filtered residues can settle to the bottom of the fermentation tank and are discharged out of the fermentation tank through the residue outlet;
and 4, step 4: the filtered materials flow in the plug flow biochemical reaction area along a designated direction, when the materials flow to the top of the fermentation tank, gas in the materials is output to the fermentation tank through an exhaust pipeline, and the materials are output to the return pipe through a first discharge hole;
and 5: the reflux pipe pumps out the materials in the fermentation tank, and carries out shunting after heat exchange, and part of the materials after heat exchange flows back to the second micro-interface generator to adjust the temperature in the fully mixed flow biochemical reaction area, and the other part of the materials is output to the separation tank for separation;
step 6: after heat exchange, the material flows back and enters the second micro-interface generator through a backflow feeding pipeline, the second micro-interface generator receives tail gas at the top of the fermentation tank through the second gas-phase feeding pipeline, the tail gas is crushed into micron-scale bubbles by using the material, the micron-scale bubbles and the material are mixed to form a gas-liquid emulsion, and after the gas-liquid emulsion is formed, the gas-liquid emulsion is output to the fully-mixed flow biochemical reaction area by the second micro-interface generator so as to adjust the temperature in the fully-mixed flow biochemical reaction area while the material is repeatedly used;
and 7: after heat exchange, the material is output to the separation tank, the separation tank can carry out gas-liquid separation on the material to form gaseous strains and fermentation liquor, after separation, the gaseous strains are discharged out of the separation tank through the exhaust port, and the fermentation liquor is discharged out of the separation tank through the second discharge port and conveyed to the next working section.
Further, when the system operates, the pH adjusting liquid feeding port can convey pH adjusting liquid to adjust the pH value of the materials in the fermentation tank.
Compared with the prior art, the method has the beneficial effects that compared with the traditional method, the method has the advantages that micron-scale micron-sized bubbles are formed by crushing air, and the micron-scale bubbles are mixed with the starch solution to form gas-liquid emulsion, so that the phase interface area of gas-liquid two phases is increased, and the effect of strengthening mass transfer within a lower preset operation condition range is achieved; meanwhile, the micron-sized bubbles can be fully mixed with the starch solution to form a gas-liquid emulsion, and the gas-liquid two-phase full mixing can ensure that lactic acid producing bacteria in the system can fully absorb oxygen in the material, so that byproducts are prevented from being generated, and the fermentation efficiency of the system is further improved. Meanwhile, a backflow feeding pipe is arranged in the fermentation tank of the system, and the material after reaction flows back to the fermentation tank, so that the contact time of sterile air and starch solution is prolonged, and the fermentation efficiency is improved. In addition, the range of the preset operation condition can be flexibly adjusted according to different product requirements or different catalysts, so that the full and effective reaction is further ensured, and the reaction rate is further ensured.
In addition, the range of the preset operation conditions can be flexibly adjusted according to different raw material compositions or different product requirements, so that the full and effective reaction is further ensured, the reaction rate is further ensured, and the purpose of strengthening the reaction is achieved.
Particularly, the full-mixed flow biochemical reaction area is arranged in the fermentation tank, the micro-interface generator is arranged in the full-mixed flow biochemical reaction area, so that the inside of the full-mixed flow biochemical reaction area is closer to a full-mixed flow model, the uniformity of the temperature and the concentration of materials in the reaction area is ensured, and the materials can be quickly and uniformly mixed when entering the reaction area, thereby preventing the by-products generated due to the fact that part of lactic acid producing bacteria in the reaction area cannot absorb enough oxygen, and further improving the fermentation efficiency of the system.
Particularly, the invention also arranges a plug flow biochemical reaction area in the fermentation tank, the plug flow biochemical reaction area enables the fermented material to move at a uniform speed along the designated direction, the material is effectively prevented from flowing back in the conveying process, and the plug flow biochemical reaction area can further promote the reaction rate of the material in the fully mixed flow biochemical reaction area, thereby further improving the fermentation efficiency of the system.
Furthermore, the fermentation tank is respectively provided with the pneumatic micro-interface generator and the gas-liquid linkage micro-interface generator, and the micron-sized bubbles and the materials are mixed more uniformly by using different types of micro-interface generators, so that the mixing efficiency of the materials and the sterile air in the fermentation tank is improved, and the fermentation efficiency of the system is further improved.
Furthermore, a grating is arranged in the fermentation tank, and residues in the materials can be effectively filtered and discharged through a residue outlet at the bottom of the fermentation tank, so that the purity of the fermentation liquor is improved.
Particularly, the side wall of the fermentation tank is also provided with a pH adjusting liquid feeding port, when the system runs, the pH adjusting liquid feeding port can adjust the pH value of materials in the fermentation tank in a mode of conveying pH adjusting liquid into the fermentation tank, so that the pH value of the materials can be effectively adjusted while lactic acid producing bacteria are not damaged, and the reaction efficiency of the lactic acid producing bacteria is improved.
Especially, the fermentation cylinder inner wall still is equipped with the baffle, the baffle is located fermentation raw materials feed inlet with the exit of fermentation bacterial feed inlet is through two the feed inlet export is sheltered from to prevent that each feed inlet from producing undulant when output material and lactic acid producing bacteria and being right the second micro-interface generator causes the influence and reduces the mixing efficiency of second micro-interface generator.
Furthermore, a return pipe is further arranged in the system, and the fermented materials are returned to be reused, so that the utilization rate of the materials is improved, and the fermentation efficiency of the system is further improved.
Particularly, the return pipe is internally provided with the heat exchanger, when the fermented materials are returned and output, the materials can be subjected to heat exchange through the heat exchanger so as to reach the specified temperature, and the temperature of the materials in the fermentation tank is adjusted, so that a proper fermentation environment is provided for lactic acid producing bacteria in the fermentation tank, and the fermentation efficiency of the system is further improved.
Drawings
FIG. 1 is a schematic structural diagram of a system for preparing lactic acid by starch fermentation according to the present invention.
Detailed Description
Preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only for explaining the technical principle of the present invention, and do not limit the scope of the present invention.
It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are only for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.
Furthermore, it should be noted that, in the description of the present invention, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
Fig. 1 is a schematic structural diagram of a lactic acid fermentation system according to the present invention, which includes a fermentation tank 1, a micro-interface generator 2 (not shown), a return pipe 3 and a separation tank 4. Wherein, micro-interface generator 2 sets up inside the fermentation cylinder for with the broken micron order bubble that forms micron yardstick of aseptic air and mix the micron order bubble with the material in the fermentation cylinder and form the gas-liquid emulsion thing thereby provide the aerobic environment for lactic acid producing bacteria in the material. The return pipe 3 is connected with the fermentation tank 1 and used for outputting the fermented materials in the fermentation tank 1 and returning part of the output materials to the fermentation tank 1. The separation tank 4 is connected with an output branch in the return pipe 3 and is used for separating and concentrating the material output by the fermentation tank 1 and outputting the treated fermentation liquor to the next working section.
When the system is operated, firstly, starch solution and lactic acid producing bacteria are conveyed into the fermentation tank 1, and simultaneously, sterile air is conveyed into the fermentation tank 1, the sterile air can enter the micro-interface generator 2, the micro-interface generator 2 breaks the sterile air to form micron-scale micro-scale bubbles and enables the micron-scale micro-scale bubbles to be mixed with the starch solution to form gas-liquid emulsion so as to provide uniform aerobic environment for the lactic acid producing bacteria, after fermentation is completed, the fermentation tank 1 can respectively discharge gas and residues generated in the fermentation process out of the system, and output the fermented material to the return pipe 3, the return pipe 3 conducts heat exchange on the material and then shunts the material, after shunting, a part of the material flows back to the fermentation tank 1, when the material is repeatedly used, the temperature of the material in the fermentation tank is adjusted, the other part of the material can be output to the separation tank 4, and the separation tank can conduct, discharging residual gaseous bacteria in the materials and outputting the fermentation liquor after separation and concentration to the next working section. It will be understood by those skilled in the art that the fermentation bacteria species used in the system may be lactic acid producing bacteria, or other species, and the present embodiment is not particularly limited as long as the species is capable of aerobic fermentation.
With continued reference to FIG. 1, the fermenter 1 of the present invention includes a mixed flow biochemical reaction area 11 and a plug flow biochemical reaction area 12. Wherein the complete mixed flow biochemical reaction zone 11 is positioned at the lower part of the fermentation tank 1 and is used for fully mixing the lactic acid producing bacteria and the micron-sized bubbles with the starch solution. The plug flow biochemical reaction area 12 is located at the upper part of the fermentation tank 1, and is used for conveying fermented materials along a specified direction while promoting the reaction speed in the fermentation tank 1. When the fermentation tank 1 starts to ferment, the mixed flow biochemical reaction area 11 respectively receives the lactic acid producing bacteria, the starch solution and the micron-sized bubbles and fully mixes the lactic acid producing bacteria, the starch solution and the micron-sized bubbles to ferment the lactic acid producing bacteria in an aerobic environment, after the fermentation is finished, the mixed flow biochemical reaction area 11 conveys the fermented material to the plug flow biochemical reaction area 12, and the plug flow biochemical reaction area 12 conveys the material to a designated direction. It is understood that the length-diameter ratio of the plug flow biochemical reaction zone 12 is not particularly limited in this embodiment, as long as the length of the plug flow biochemical reaction zone 12 is sufficient to maintain a continuous and stable flow of the material.
Referring to fig. 1, the mixed flow biochemical reaction area 11 of the present invention includes a grating 111, a pH adjusting liquid inlet 112, a fermentation material inlet 113, a fermentation strain inlet 114, a first gas phase inlet channel 115, a residue outlet 116, and a partition 117. Wherein, the grating 111 is arranged inside the fermentation tank 1 for filtering the residue generated in the fermentation process of the fermentation tank 1. The pH adjusting liquid feeding hole is formed in the inner wall of the fermentation tank 1 and located above the grating 111, and is used for conveying pH adjusting liquid to the fermentation tank 1. The fermentation raw material inlet 113 is arranged on the side wall of the fermentation tank 1 and below the grid 111, and is used for conveying starch to the fermentation tank 1. The fermentation strain feed port 114 is disposed on the sidewall of the fermentation tank 1 and below the fermentation material feed port 113, and is used for conveying lactic acid producing bacteria to the fermentation tank 1. The first gas phase feed line 115 is provided in the side wall of the fermenter 1 and connected to the micro-interface generator 2 for supplying sterile air. The residue outlet 116 is disposed at the bottom of the fermentation tank 1 for discharging the residue generated after fermentation out of the fermentation tank 1. The partition 117 is disposed on the inner wall of the fermentation tank 1 and located on the same side as the fermentation material inlet 113 to block the starch solution output from the fermentation material inlet 113 and the fluctuation generated when the lactic acid producing bacteria are output from the fermentation bacteria inlet 114.
When the mixed flow biochemical reaction zone operates, the fermentation raw material inlet 113 can convey starch solution to the inside of the fermentation tank 1, the fermentation strain inlet 114 can convey lactic acid producing bacteria to the inside of the fermentation tank 1, the baffle 117 can block the fluctuation generated when the fermentation raw material inlet 113 and the fermentation strain inlet 114 output materials, the first gas-phase inlet pipeline 115 can convey sterile air to the micro-interface generator 2, the micro-interface generator 2 breaks the sterile air to form micron-scale bubbles, and the micron-scale bubbles are mixed with the starch solution to form gas-liquid emulsion, the gas-liquid emulsion is mixed with the lactic acid producing bacteria to start fermentation, in the fermentation process, the pH adjusting liquid inlet 113 can convey pH adjusting liquid to the fermentation tank 1 to adjust the pH value of the mixed material in the fermentation tank 1, after the fermentation is completed, the mixed flow biochemical reaction zone 11 can convey the fermented material to the flat plug flow biochemical reaction zone 12, during the transportation, the grid 111 will filter out the residues in the material, which after filtering out start to settle and leave the fermentation tank 1 through the residue outlet 116.
Specifically, the grating 111 is a sieve plate, which is disposed inside the fermentation tank 1 for filtering the fermented material. After the complete fermentation of the mixed flow biochemical reaction zone 11, the fermented material will flow through the grating 111, and the grating 111 will filter the residue in the material. It is understood that the kind of the grid 111 and the size of the through holes are not particularly limited in this embodiment, as long as the grid 111 can filter solid phase residues in the material.
In particular, the first gas feed line 115 is arranged in the side wall of the fermenter and the outlet of the first gas feed line 115 is connected to the micro-interfacial generator 2 for feeding sterile air to the micro-interfacial generator 2. When the completely mixed flow biochemical reaction zone 11 is operated, the first gas phase feeding pipe 115 can convey the sterile air to the micro interface generator 2, the micro interface generator 2 can crush the sterile air to form micron-sized bubbles, and the micron-sized bubbles are output to the interior of the fermentation tank 1 and are mixed with the starch solution. It is understood that the material and dimensions of first gas feed conduit 115 are not particularly limited in this embodiment, provided that first gas feed conduit 115 is capable of delivering a specified volume of sterile air over a specified period of time.
Specifically, the partition 117 is a baffle plate fixedly connected to the inner wall of the fermentation tank 1 for blocking the fluctuation of the fermentation tank when receiving the material. When the complete mixed flow biochemical reaction zone 11 is operated, the fermentation raw material inlet 113 can convey starch solution into the fermentation tank 1, the fermentation strain inlet 114 can convey lactic acid producing bacteria into the fermentation tank 1, and the partition plate 117 can be blocked at the discharging position, so that the fluctuation of the two materials in the conveying process is prevented, and the influence of the fluctuation on the micro-interface generator is prevented. It will be appreciated that the connection of the partition 117 to the fermenter 1 may be by welding, by integral connection or by other types of connection, provided that the partition 117 is able to reach its designated operating condition.
Referring to fig. 1, the plug flow biochemical reaction area 12 of the present invention is located at the upper portion of the fermentation tank 1, and is used for transporting fermented materials along a designated direction, and includes an exhaust pipe 121, a second gas phase feeding pipe 122, a first discharge port 123 and a return feeding pipe 124. Wherein the exhaust pipeline 121 is arranged at the top of the fermentation tank 1 for exhausting gas generated in the fermentation process. The second gas phase feed line 122 is arranged at the top of the fermenter 1 and connected to the micro-interface generator 2 for feeding the fermenter top off-gas. The first discharge port 123 is arranged on the side wall of the fermentation tank 1 and used for outputting fermented materials. The backflow feeding pipe 124 is disposed on the sidewall of the fermentation tank 1 and below the discharge port 123, and is used for feeding the backflow materials to the fermentation tank 1. When the plug flow reaction zone 12 is in operation, the material is conveyed upward at a constant speed in the reaction zone, when the material reaches the top of the fermentation tank 1, the gas in the material is output from the fermentation tank 1 through the exhaust pipe 121, the liquid-phase material is output to the return pipe 3 through the first discharge port 123, and part of the material is returned through the return pipe 3 and then returned to the fermentation tank 1 through the return feed pipe 124, after the return, the second gas-phase feed pipe 122 conveys the tail gas to the micro-interface generator 2, and the tail gas is mixed with the returned material after being crushed and conveyed to the fully mixed flow biochemical reaction zone 11 for reuse.
Specifically, the second gas phase feeding pipe 122 is disposed at the top of the fermentation tank, and the outlet of the second gas phase feeding pipe 122 is connected to the micro-interface generator 2, so as to convey the tail gas from the top of the fermentation tank to the micro-interface generator 2. When the plug flow biochemical reaction region 12 operates, the second gas phase feeding pipe 122 will feed the tail gas to the micro interface generator 2, and the micro interface generator 2 will crush the tail gas to form micro-bubbles, and the micro-bubbles are output to the inside of the fermentation tank 1 and mixed with the material. It is understood that the material and size of the second gas-phase feed pipe 122 are not particularly limited in this embodiment, as long as the second gas-phase feed pipe 122 can deliver a given volume of off-gas in a given time.
Specifically, the backflow feeding pipe 124 is disposed on the sidewall of the fermentation tank 1, and the outlet of the backflow feeding pipe 124 is connected to the micro-interfacial surface generator 2, so as to convey the backflow materials to the micro-interfacial surface generator 2. When the plug flow biochemical reaction zone is in operation, the return pipe 3 will deliver the returned material to the return feed pipe 124, and the return feed pipe 124 will deliver the material to the micro-interface generator 2 to mix the material with the micro-scale bubbles. It is understood that the material and size of the backflow feeding pipe 124 are not limited in this embodiment, as long as the backflow feeding pipe 124 can deliver a given flow rate of material in a given time.
Referring still to fig. 1, the micro-interface generator 2 of the present invention includes a first micro-interface generator 21 and a second micro-interface generator 22. Wherein the first micro-interface generator 21 is disposed at the bottom of the mixed flow biochemical reaction zone 11 for breaking the sterile air to form micro-scale bubbles. The second micro-interface generator 22 is disposed on the top of the mixed flow biochemical reaction region 11 and connected to the grid 111, and is used for breaking the sterile air into micro-bubbles and mixing the micro-bubbles with the backflow material. When the fermentation tank 1 is in operation, the first micro-interface generator 21 can crush the sterile air to form micron-sized bubbles, and mix the micron-sized bubbles with the starch solution to form a gas-liquid emulsion, and the second micro-interface generator 22 receives the returned material and the sterile air respectively, crushes the sterile air into the micron-sized bubbles, and mixes the micron-sized bubbles with the material to form the gas-liquid emulsion. It is understood that the micro-interface generator 2 of the present invention can also be used in other multi-phase reactions, such as multi-phase fluid, micro-nano-scale particle, micro-bubble micro-emulsion, micro-flow, micro-dispersion, two micro-mixed flow, micro-turbulence, micro-bubble flow, micro-bubble, micro-bubble micro-bubble flow, micro-nano-scale bubble flow, micro-bubble flow, micro-nano-scale particle, micro-bubble micro-fluid, micro-bubble micro-bubble flow, micro-bubble micro-, Or multiphase fluid (micro interface fluid for short) formed by micro-nano-scale particles, thereby effectively increasing the phase boundary mass transfer area between the gas phase and/or the liquid phase and/or the solid phase in the reaction process.
Specifically, the first micro-interface generator 21 of the present invention is a pneumatic micro-interface generator, which is connected to the first gas phase feeding pipe 115, and is used for breaking up the air conveyed by the first gas phase feeding pipe 115 and forming micron-sized bubbles. When the fermentation tank 1 is in operation, the first gas phase feeding pipe 115 will feed the sterile air to the first micro-interface generator 21, the first micro-interface generator 21 will break the sterile air and form micron-sized bubbles, and after the breaking, the first micro-interface generator 21 will output the micron-sized bubbles to the inside of the fermentation tank 1 and mix with the starch solution to provide an aerobic environment for the lactic acid producing bacteria.
Specifically, the second micro-interface generator 22 of the present invention is a gas-liquid linkage micro-interface generator, which is connected to the second gas-phase feeding pipe 122 and the backflow feeding pipe 124, respectively, for receiving the tail gas and the backflow material, respectively, and crushing the tail gas into micron-sized micro-bubbles through the pressure of the backflow material. When the second micro-interface generator 22 operates, it will receive the tail gas and the backflow material, respectively, and utilize the pressure energy of the backflow material to break the tail gas into micron-sized bubbles, and form a gas-liquid emulsion by mixing the micron-sized bubbles with the backflow material and output the gas-liquid emulsion to the complete mixed flow biochemical reaction zone 11 for repeated fermentation.
With continued reference to fig. 1, the return line 3 according to the invention comprises a circulation pump 31 and a heat exchanger 32. Wherein the circulating pump 31 is connected with the first material outlet 123 for pumping out the fermented material in the fermentation tank 1. The heat exchanger 32 is connected with the circulating pump 31 and used for exchanging heat for the material output by the circulating pump 31. After the fermentation of the materials in the fermentation tank 1 is completed, the circulation pump 31 starts to operate, the materials are pumped out through the first material outlet 123, and the materials are conveyed to the heat exchanger 32, the heat exchanger 32 exchanges heat with the materials and splits the heat exchanged materials, a part of the materials is refluxed to the reflux feeding pipeline 124, and another part of the materials is output to the separation tank 4. It is understood that the type and power of the circulating pump 31 are not particularly limited in this embodiment, as long as the circulating pump 31 can reach its designated operating state.
Specifically, a diversion pipeline is arranged at the outlet of the heat exchanger 32, one end of the diversion pipeline is connected with the backflow feeding pipeline 124 for returning a part of the materials output by the heat exchanger 32, and the other end of the diversion pipeline is connected with the separation tank 4 for outputting another part of the materials output by the heat exchanger 32 to the separation tank 4 for separation.
With reference to fig. 1, the separating tank 4 of the present invention is a sealed tank, and a feeding port is disposed at the top end of the sealed tank, and the feeding port is connected to the heat exchanger 32 for receiving the material after completion of waste heat; the top end of the separation tank 4 is also provided with an exhaust port for exhausting gaseous bacteria during separation; and a second discharge hole is formed in the bottom end of the separation tank 4 and used for outputting the separated fermentation liquor to the next working section. When the heat exchanger 32 outputs the heat-exchanged material, the material enters the separation tank 4 through the feed inlet and is subjected to gas-liquid separation, the lactic acid producing bacteria remaining in the material are discharged out of the separation tank 4 through the exhaust port together with the gas after separation, and the material is separated to form fermentation liquor and is output to the next working section through the second discharge port. It is understood that the material and size of the separation tank 4 are not limited in this embodiment, as long as the separation tank 4 can reach its designated working state.
In order that the objects and advantages of the invention will be more clearly understood, the invention is further described below with reference to examples; it should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
A lactic acid fermentation process comprising the steps of:
step 1: conveying the starch solution of the specified type to a complete mixed flow biochemical reaction area in the fermentation tank through the fermentation raw material feeding hole, and conveying the lactic acid producing bacteria to the fermentation tank through the fermentation strain feeding hole;
step 2: conveying sterile air to the first micro-interface generator through the first gas-phase feeding pipeline, crushing the sterile air into micron-sized bubbles by the first micro-interface generator, outputting the micron-sized bubbles into a starch solution in the fermentation tank, and sufficiently mixing the micron-sized bubbles with the starch solution to provide an aerobic environment for lactic acid producing bacteria;
and step 3: the lactic acid producing bacteria and the starch solution react in an aerobic environment, after fermentation is completed, the fermentation tank conveys the fermented material to the plug flow biochemical reaction area, the material flows through the grating, the grating can filter residues in the material, and the filtered residues can settle to the bottom of the fermentation tank and are discharged out of the fermentation tank through the residue outlet;
and 4, step 4: the filtered materials flow in the plug flow biochemical reaction area along a designated direction, when the materials flow to the top of the fermentation tank, gas in the materials is output to the fermentation tank through an exhaust pipeline, and the materials are output to the return pipe through a first discharge hole;
and 5: the reflux pipe pumps out the materials in the fermentation tank, and carries out shunting after heat exchange, and part of the materials after heat exchange flows back to the second micro-interface generator to adjust the temperature in the fully mixed flow biochemical reaction area, and the other part of the materials is output to the separation tank for separation;
step 6: after heat exchange, the material flows back and enters the second micro-interface generator through a backflow feeding pipeline, the second micro-interface generator receives tail gas through the second gas phase feeding pipeline, the tail gas is crushed by the material to form micron-scale bubbles, the micron-scale bubbles and the material are mixed to form a gas-liquid emulsion, and after the gas-liquid emulsion is formed, the gas-liquid emulsion is output to the fully mixed flow biochemical reaction area by the second micro-interface generator so as to regulate the temperature in the fully mixed flow biochemical reaction area while the material is repeatedly used;
and 7: after heat exchange, the material is output to the separation tank, the separation tank can carry out gas-liquid separation on the material to form gaseous strains and fermentation liquor, after separation, the gaseous strains are discharged out of the separation tank through the exhaust port, and the fermentation liquor is discharged out of the separation tank through the second discharge port and conveyed to the next working section.
Specifically, when sterilized potato starch is put into a fermentation tank in the fermentation unit 4, 3L of fermentation raw material is charged into the fermentation tank, seeds are inoculated at an inoculation amount of 10%, the rotation speed is controlled to 240 + -2 r/min, the ventilation rate is 35L/h, the temperature is controlled to 30-32 ℃, and the fermentation time is 60-72 h. The pH adjusting tank is filled with light calcium carbonate and the pH of the solution in the fermentation tank is controlled to be maintained at 5.1-5.2.
Example one
Fermenting the starch solution to prepare lactic acid by using the system and the process, wherein:
when the sterilized potato starch is put into the fermentation tank in the fermentation unit 4, 3L of fermentation raw material is charged into the fermentation tank, seeds are inoculated according to the inoculation amount of 10%, the rotation speed is controlled at 238r/min, the ventilation amount is 35L/h, the temperature is 30 ℃, and the fermentation time is 60 h. The pH adjusting tank is filled with light calcium carbonate and the pH of the solution in the fermentation tank is controlled to be maintained at 5.1.
The purity of the lactic acid prepared by using the system of the invention is 99.51 percent through detection.
Example two
Fermenting the starch solution to prepare lactic acid by using the system and the process, wherein:
when the sterilized potato starch was put into the fermentation tank in the fermentation unit 4, 3L of fermentation raw material was charged into the fermentation tank, and the seeds were inoculated at an inoculum size of 10%, and the rotation speed was controlled at 240r/min, the aeration rate at 35L/h, the temperature at 31 ℃ and the fermentation time at 66 h. The pH adjusting tank is filled with light calcium carbonate and the pH of the solution in the fermentation tank is controlled to be maintained at 5.1.
The purity of the lactic acid prepared by using the system provided by the invention is 99.73% through detection.
EXAMPLE III
Fermenting the starch solution to prepare lactic acid by using the system and the process, wherein:
when the sterilized potato starch was put into the fermentation tank in the fermentation unit 4, 3L of fermentation raw material was charged into the fermentation tank, and the seeds were inoculated at an inoculum size of 10%, while controlling the rotation speed at 242r/min, the aeration rate at 35L/h, the temperature at 32 ℃ and the fermentation time at 72 h. The pH adjusting tank is filled with light calcium carbonate and the pH of the solution in the fermentation tank is controlled to be maintained at 5.2.
Through detection, the purity of the lactic acid prepared by using the system provided by the invention is 99.89%.
Comparative example
The starch solution was fermented to produce lactic acid using the prior art, wherein the fermentation process of this comparative example was carried out with the same phase parameters as the examples.
The purity of the lactic acid prepared by using the system provided by the invention is 99.09% through detection.
So far, the technical solutions of the present invention have been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present invention is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the invention, and the technical scheme after the changes or substitutions can fall into the protection scope of the invention.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention; various modifications and alterations to this invention will become apparent to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. A system for producing lactic acid by fermentation of starch, comprising:
a fermentor for fermenting a material with lactic acid producing bacteria, the fermentor comprising: a complete mixed flow biochemical reaction area which is arranged below and used for loading starch solution and lactic acid producing bacteria and providing reaction space for the fermentation of the starch solution and the lactic acid producing bacteria, and a plug flow biochemical reaction area which is arranged above and used for conveying fermented materials and separating gas from liquid;
the separation tank is connected with the fermentation tank and is used for separating the materials output by the fermentation tank to generate gaseous strains and fermentation liquor;
at least two micro-interface generators which are respectively arranged at the appointed positions in the fully mixed flow reaction zone, convert the pressure energy of gas and/or the kinetic energy of liquid into the surface energy of bubbles and transmit the surface energy to the sterile air, so that the sterile air is crushed into micron-sized bubbles with the diameter of more than or equal to 1 mu m and less than 1mm to improve the mass transfer area between the starch solution and the sterile air, reduce the thickness of a liquid film and reduce the mass transfer resistance, and the starch solution and the micron-sized bubbles are mixed to form a gas-liquid emulsion after being crushed, so as to strengthen the mass transfer efficiency between the starch solution and the sterile air within the range of preset operation conditions;
and the return pipes are respectively connected with the fermentation tank and the separation tank and used for exchanging heat of the materials output by the fermentation tank and shunting the materials after heat exchange so as to respectively return to the fermentation tank or output to the separation tank.
2. The system for producing lactic acid by starch fermentation according to claim 1, wherein the micro-interface generator comprises:
the first micro-interface generator is a pneumatic micro-interface generator, is arranged in the complete mixed flow biochemical reaction zone and is positioned at the bottom of the reaction zone, and is used for crushing sterile air to form micron-scale bubbles and outputting the micron-scale bubbles to the fermentation tank after the crushing is finished;
and the second micro-interface generator is an air-liquid linkage type micro-interface generator, is arranged in the full-mixed flow biochemical reaction area and is positioned at the top of the reaction area, is used for receiving the material output by the return pipe, uses the material to crush the sterile air to form micron-scale micron-sized bubbles, and mixes the micron-scale bubbles with the material to form an air-liquid emulsion to be output to the full-mixed flow biochemical reaction area.
3. The system for preparing lactic acid by starch fermentation according to claim 1, wherein the totally mixed flow biochemical reaction zone in the fermentation tank comprises:
the grating is arranged inside the fermentation tank and is used for filtering insoluble particles in the material;
the pH adjusting liquid feeding port is arranged on the side wall of the fermentation tank, is positioned above the grating and is used for conveying pH adjusting liquid to adjust the pH value of the material;
the fermentation raw material feeding hole is formed in the side wall of the fermentation tank, is positioned below the grating and is used for conveying starch solution;
the fermentation strain feeding hole is formed in the side wall of the fermentation tank and is positioned below the fermentation raw material feeding hole, and is used for conveying lactic acid producing bacteria to the interior of the fermentation tank and fermenting starch solution;
a first gaseous feed conduit disposed in a side wall of the fermentor and connected to the micro-interface generator for lateral delivery of sterile air into the micro-interface generator within the fermentor;
a residue outlet arranged at the bottom of the fermentation tank and used for discharging fermented residue out of the system;
the baffle, it set up in fermentation cylinder inner wall is located the grid below for block the starch of fermentation raw materials feed inlet output with the fluctuation that lactic acid producing bacteria produced of fermentation bacterial feed inlet output.
4. The system for producing lactic acid by starch fermentation according to claim 1, wherein the plug flow reaction zone comprises:
the exhaust pipeline is arranged at the top end of the fermentation tank and used for exhausting tail gas generated in the fermentation of the materials in the fermentation tank;
the second gas-phase feeding pipeline is arranged at the top end of the fermentation tank, is connected with the micro-interface generator and is used for conveying the tail gas generated at the top of the fermentation tank into the micro-interface generator in the fermentation tank;
the discharge port is arranged on the side wall of the fermentation tank and used for outputting the fermented materials out of the fermentation tank;
and the backflow feeding pipeline is arranged on the side wall of the fermentation tank and used for outputting part of materials output by the backflow pipe to the micro-interface generator in the fermentation tank.
5. The system for producing lactic acid by starch fermentation according to claim 1, wherein the return pipe comprises:
the circulating pump is connected with the fermentation tank and used for outputting materials fermented in the fermentation tank;
and the heat exchanger is connected with the circulating pump and used for exchanging heat of the material output by the circulating pump so as to enable the material to reach the specified temperature.
6. The system for preparing lactic acid through starch fermentation according to claim 1, wherein the output end of the heat exchanger is provided with a shunt pipe, and the shunt pipe is respectively connected with the fermentation tank and the separation tank and is used for respectively refluxing the materials and outputting the materials to the separation tank.
7. The system for producing lactic acid by starch fermentation according to claim 1, wherein the separation tank is a sealed tank comprising:
the feeding hole is arranged at the top end of the separation tank and used for conveying the material output by the return pipe to the inside of the separation tank;
the exhaust port is arranged at the top end of the separation tank and used for outputting gaseous strains;
and the discharge port is arranged at the bottom end of the separation tank and used for outputting the separated fermentation liquor and conveying the fermentation liquor to the next working section.
8. A process for preparing lactic acid by starch fermentation is characterized by comprising the following steps:
step 1: conveying the starch solution of the specified type to a complete mixed flow biochemical reaction area in the fermentation tank through the fermentation raw material feeding hole, and conveying the lactic acid producing bacteria to the fermentation tank through the fermentation strain feeding hole;
step 2: conveying sterile air to the first micro-interface generator through the first gas-phase feeding pipeline, crushing the sterile air into micron-sized bubbles by the first micro-interface generator, outputting the micron-sized bubbles into a starch solution in the fermentation tank, and sufficiently mixing the micron-sized bubbles with the starch solution to provide an aerobic environment for lactic acid producing bacteria;
and step 3: the lactic acid producing bacteria and the starch solution react in an aerobic environment, after fermentation is completed, the fermentation tank conveys the fermented material to the plug flow biochemical reaction area, the material flows through the grating, the grating can filter residues in the material, and the filtered residues can settle to the bottom of the fermentation tank and are discharged out of the fermentation tank through the residue outlet;
and 4, step 4: the filtered materials flow in the plug flow biochemical reaction area along a designated direction, when the materials flow to the top of the fermentation tank, gas in the materials is output to the fermentation tank through an exhaust pipeline, and the materials are output to the return pipe through a first discharge hole;
and 5: the reflux pipe pumps out the materials in the fermentation tank, and carries out shunting after heat exchange, and part of the materials after heat exchange flows back to the second micro-interface generator to adjust the temperature in the fully mixed flow biochemical reaction area, and the other part of the materials is output to the separation tank for separation;
step 6: after heat exchange, the material flows back and enters the second micro-interface generator through a backflow feeding pipeline, the second micro-interface generator receives tail gas at the top of the fermentation tank through the second gas-phase feeding pipeline, the tail gas is crushed into micron-scale bubbles by using the material, the micron-scale bubbles and the material are mixed to form a gas-liquid emulsion, and after the gas-liquid emulsion is formed, the gas-liquid emulsion is output to the fully-mixed flow biochemical reaction area by the second micro-interface generator so as to adjust the temperature in the fully-mixed flow biochemical reaction area while the material is repeatedly used;
and 7: after heat exchange, the material is output to the separation tank, the separation tank can carry out gas-liquid separation on the material to form gaseous strains and fermentation liquor, after separation, the gaseous strains are discharged out of the separation tank through the exhaust port, and the fermentation liquor is discharged out of the separation tank through the second discharge port and conveyed to the next working section.
9. The process for preparing lactic acid through starch fermentation according to claim 8, wherein the pH adjusting liquid feed port delivers a pH adjusting liquid for adjusting the pH of the material in the fermentation tank during the operation of the system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910860707.2A CN112481107A (en) | 2019-09-11 | 2019-09-11 | System and process for preparing lactic acid by starch fermentation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910860707.2A CN112481107A (en) | 2019-09-11 | 2019-09-11 | System and process for preparing lactic acid by starch fermentation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112481107A true CN112481107A (en) | 2021-03-12 |
Family
ID=74920560
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910860707.2A Withdrawn CN112481107A (en) | 2019-09-11 | 2019-09-11 | System and process for preparing lactic acid by starch fermentation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112481107A (en) |
-
2019
- 2019-09-11 CN CN201910860707.2A patent/CN112481107A/en not_active Withdrawn
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103627621A (en) | Solid-state vertical fertilization, self-circulation cooling and distillation integrated device and method | |
| CN206396227U (en) | A kind of hyaluronic acid production fermentation tank | |
| CN207294776U (en) | A kind of airflow stirring fermentation tank | |
| CN112481073B (en) | Micro-interface enhanced fermentation system and process | |
| CN208649156U (en) | A kind of Straw manures installation for fermenting | |
| CN210419971U (en) | Lactic acid fermentation device | |
| CN112481108A (en) | Amino acid fermentation system and process | |
| CN112481101A (en) | Aerobic fermentation system and process | |
| CN205443312U (en) | Hydrologic cycle oxygenation fermentation cylinder for bio -pharmaceuticals | |
| CN112481107A (en) | System and process for preparing lactic acid by starch fermentation | |
| CN207062272U (en) | A kind of Double shaft stirring fermentation tank | |
| CN111517847A (en) | Microbial fertilizer fermentation equipment and preparation method thereof | |
| CN110839694A (en) | Dairy product fermentation tank | |
| CN112481072B (en) | Citric acid fermentation system and process | |
| CN210916041U (en) | Backflow stirring fermentation tank | |
| CN112481097A (en) | Penicillin fermentation system and process | |
| TWM507428U (en) | Structural improvement of normal pressure liquid state fermentation tank | |
| CN208949273U (en) | Fermentation tank for microbial fermentation | |
| CN209065915U (en) | A kind of nitrifier of multistage amplification automatically spreads cultivation device online | |
| CN108410704B (en) | Chambered bioreactor and method thereof | |
| CN213556754U (en) | Mixer for biological materials | |
| CN106701540A (en) | Air intake system for airlift fermentation tank | |
| CN205556680U (en) | A anaerobic reactor for kitchen garbage handles | |
| CN201762318U (en) | Jet flow internal circulation fermentation tank | |
| CN213570416U (en) | Fermentation system suitable for high-density fermentation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WW01 | Invention patent application withdrawn after publication | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20210312 |