Glutamic acid fermentation broth concentration steam recovery system and its recovery and utilization method

Abstract

This invention discloses a glutamic acid fermentation broth concentration steam recovery system and its recovery and utilization method. The system includes an ammonia-containing steam pipeline, a primary water pipeline, an ammonia removal tower, a condenser, a condensate storage tank, and a concentrated ammonia storage tank. The recovery and utilization method includes: (1) ammonia absorption; (2) condensation. The condensate is used for the fermentation of glutamic acid, and part of the concentrated ammonia is used to adjust the pH of the glutamic acid fermentation medium, and the other part is used for power plant flue gas desulfurization. Beneficial effects: The glutamic acid fermentation broth concentration steam recovery system disclosed in this invention has a simple connection structure, is easy to implement, and avoids direct discharge and environmental pollution; it achieves zero wastewater discharge; the recovery and utilization method disclosed in this invention achieves the recovery and utilization of water resources and concentrated ammonia, reducing the cost of glutamic acid production; it ensures normal nutrient concentration and improves fermentation indicators; it reduces the amount of liquid nitrogen used, reducing production costs; it avoids ammonia pollution in the batching area and ensures the health of the staff.

Description

Technical fields:

[0001] This invention patent belongs to the field of glutamic acid production technology, specifically relating to a glutamic acid fermentation broth concentration steam recovery system and its recovery and utilization method. Background technology:

[0002] Glutamic acid, also known as α-aminoglutarate, is an acidic amino acid containing one amino group and two carboxyl groups. It plays a crucial role in protein metabolism within organisms, participating in the synthesis of proteins, polypeptides, and fatty acids, and regulating ammonia levels in the body along with glutamine. It also acts as an excitatory neurotransmitter, participating in information transmission. Glutamic acid has wide applications in food, medicine, cosmetics, and agriculture. L-glutamic acid is a precursor to monosodium glutamate (MSG). L-glutamate has a strong umami flavor and is the most consumed flavoring agent in the world after sugar and salt. L-glutamic acid hydrochloride can be used to improve the bitterness of beer and is also used as a salt substitute, nutritional supplement, and flavor enhancer.

[0003] Currently, monosodium glutamate (MSG) producers manufacture glutamic acid through fermentation. Over the past 50 years, fermentation technology has made significant progress. Glutamic acid fermentation has gone through several stages: sub-optimal biotin production, high biotin production, and production using temperature-sensitive strains. The intensity of fermentation production has increased significantly, with the acid production level rising from 15-18% in the sub-optimal method to 20-23% in the temperature-sensitive method. The conversion rate has also increased from 65-68% to 67-72%. Currently, industrial production mainly uses temperature-sensitive strains for glutamic acid production.

[0004] Glutamic acid extraction mainly employs the continuous isoelectric point method. The fermentation broth is first concentrated by evaporation in a single-effect evaporator, then separated by a first gas-liquid separator. The separated liquid is then concentrated again by evaporation in a second-effect evaporator, followed by another gas-liquid separation in a second gas-liquid separator. The separated liquid is then concentrated by evaporation in a third-effect evaporator, and then sent to a third gas-liquid separator for further gas-liquid separation. The separated liquid is then returned to the second-effect evaporator for further concentration, and this cycle continues. When the concentration of the fermentation broth in the third gas-liquid separator reaches the set value, it is sent to the concentrate storage tank. The concentrated fermentation broth is then subjected to continuous isoelectric point extraction to obtain crude glutamic acid, which is finally refined through neutralization, decolorization, and other steps to obtain finished product glutamic acid. During the concentration and evaporation process of glutamic acid fermentation broth, the first, second, and third gas-liquid separators will separate a large amount of ammonia-containing vapor, which will then be condensed into condensate. This condensate has the characteristics of high ammonia nitrogen content and high pH. Direct discharge will cause environmental pollution, so it must be treated before discharge. Enterprises have to invest a lot of money in wastewater treatment, thereby increasing the production cost of glutamic acid.

[0005] The patent with application number CN200710014052.4 discloses a new environmentally friendly process for glutamic acid fermentation, which discloses the recovery of ammonia vapor condensate generated during the glutamic acid fermentation concentration process, and then mixing it with primary water at a ratio of 1:0.1-0.3 before applying it to the fermentation of ingredients; the patent with application number CN201210562044.4 discloses a method for recycling monosodium glutamate fermentation condensate, which discloses the collection of condensate from the original fermentation culture medium during the fermentation process, replacing primary water and reusing it to adjust the post-fermentation culture medium for the fermentation production of glutamic acid. However, both of the above patents have the following problems: 1. If the condensate is directly used in the fermentation process of ingredients, due to the high pH, ​​it is easy to form a precipitate with some amino acids and inorganic salt ions in the culture medium. The formation of precipitate will cause the following problems: (1) it will lead to incomplete sterilization, resulting in contamination of the fermentation culture medium; (2) it will lead to a decrease in the concentration of nutrients, resulting in low fermentation indicators; 2. In addition, the ammonia in the condensate is volatile, which will cause the ammonia concentration in the ingredient preparation area to increase, thereby leading to air pollution and affecting the health of personnel. Summary of the Invention:

[0006] In view of this, the purpose of the present invention is to provide a glutamic acid fermentation broth concentration steam recovery system and its recovery and utilization method. The glutamic acid fermentation broth concentration steam recovery system provided by the present invention has a simple connection structure, avoids direct discharge of condensate water and environmental pollution, and reduces the cost of glutamic acid production.

[0007] The present invention discloses a glutamic acid fermentation broth concentration steam recovery system, which includes an ammonia-containing steam pipeline, a primary water pipeline, an ammonia removal tower, a condenser, a condensate storage tank, and a concentrated ammonia water storage tank. The outlet of the ammonia-containing steam pipeline is connected to the inlet of the ammonia removal tower, and the outlet of the primary water pipeline is connected to the spray water inlet of the ammonia removal tower. The top outlet of the ammonia removal tower is connected to the inlet of the condenser, and the outlet of the condenser is connected to the inlet of the condensate storage tank. The bottom outlet of the ammonia removal tower is connected to the inlet of the concentrated ammonia water storage tank.

[0008] Furthermore, it also includes a cooler and an ammonia density meter. The bottom outlet of the ammonia removal tower is connected to the inlet of the cooler, and the outlet of the cooler is connected to the inlet of the ammonia removal tower. The ammonia density meter is installed at the bottom outlet of the ammonia removal tower. A first control valve is installed on the pipeline between the ammonia removal tower and the cooler, and a second control valve is installed on the pipeline between the ammonia removal tower and the concentrated ammonia storage tank.

[0009] Another aspect of the technical solution of the present invention discloses a method for recovering and utilizing concentrated steam from glutamic acid fermentation broth, which includes the following steps: (1) absorbing ammonia; (2) condensing;

[0010] (1) Ammonia absorption: Ammonia-containing vapor enters the lower part of the ammonia removal tower with an internal pressure of 340-360 mbar, and primary water at 15-20°C is sprayed downward from the top of the ammonia removal tower; the ammonia in the ammonia-containing vapor gradually dissolves in the primary water, and the resulting ammonia water falls to the bottom of the ammonia removal tower.

[0011] (2) Condensation: The vapor after ammonia removal in step (1) is discharged from the top outlet of the deammoniation tower and enters the condenser, where it is condensed and liquefied into condensate with a pH of 9-9.5.

[0012] Furthermore, the ammonia water from step (1) is cooled to 10-12°C in a cooler, and then sent to the middle section of the ammonia removal tower to continue absorbing ammonia from the ammonia-containing vapor. The ammonia water density meter displays a density value of 0.91-0.94 g / cm³. 3 At that time, close the first control valve and open the second control valve to pump concentrated ammonia into the concentrated ammonia storage tank.

[0013] Furthermore, the condensate is used for the fermentation of glutamic acid, and part of the concentrated ammonia is used to adjust the pH of the glutamic acid fermentation medium, while the other part is used for desulfurization of power plant flue gas.

[0014] Furthermore, the specific process method for applying the condensate and the concentrated ammonia to the fermentation of glutamic acid and adjusting the pH of the fermentation medium includes the following steps: (1) pretreatment; (2) continuous sterilization; (3) preparation of fermentation medium; (4) pH adjustment; (5) glutamic acid fermentation;

[0015] (1) Pretreatment: Add 20-25% of the condensed water or primary water to the mixing tank A by mass percentage, then add 8-10% corn steep liquor, 0.8-1.5% soybean meal hydrolysate, and 0.3-0.9% molasses, and mix evenly to form material A; then add 8-12% of the condensed water or primary water to the mixing tank B by mass percentage, heat to 45-55℃, then add 0.2-0.5% potassium chloride, 0.1-0.4% magnesium sulfate, 0.1-0.4% betaine, 0.001-0.002% ferrous sulfate, 0.001-0.002% manganese sulfate, and 0.001-0.002% zinc sulfate, and mix evenly to form material B;

[0016] (2) Continuous sterilization: The materials A and B in step (1) are continuously sterilized at a temperature of 125-127℃ for 20-25 minutes, and then cooled to 32-35℃.

[0017] (3) Prepare fermentation medium: Add 15-23% of the condensate, 8-12% of the low sugar, 30-37% of the material A sterilized in step (2), 4-6% of the condensate, 8-12% of the material B sterilized in step (2) and 18-22% of the condensate into the fermenter in sequence according to the mass percentage to obtain a fermentation medium with a pH of 3.0-3.5;

[0018] (4) Adjust pH: Add liquid ammonia to the fermentation medium in step (3) to adjust the pH to 7.0;

[0019] (5) Glutamic acid fermentation: The temperature-sensitive Corynebacterium glutamicum seed culture with an OD value of at least 1.0 is inoculated into the fermentation medium with a pH of 7.0 in step (4) and fermented for 32 hours; the volume of the inoculated temperature-sensitive Corynebacterium glutamicum seed culture accounts for 10%-15% of the volume of the fermentation medium.

[0020] Furthermore, step (3) of preparing the fermentation medium also includes the following methods:

[0021] According to the mass percentage, 15-23% primary water, 8-12% low sugar, 33-37% of the material A sterilized in step (2), 4-6% primary water, 8-12% of the material B sterilized in step (2), and 18-22% of the concentrated ammonia water are sequentially added into the fermenter to obtain a fermentation medium with a pH of 4.0-4.5.

[0022] Furthermore, step (3) of preparing the fermentation medium also includes the following methods:

[0023] According to the mass percentage, 15-23% of the condensate, 8-12% of the low sugar, 33-37% of the material A sterilized in step (2), 4-6% of the condensate, 8-12% of the material B sterilized in step (2), and 18-22% of the concentrated ammonia water are sequentially added into the fermenter to obtain a fermentation medium with a pH of 4.5-5.0.

[0024] Furthermore, the low sugar in step (3) is a glucose solution with a concentration of 33-36%.

[0025] Advantages of this invention:

[0026] 1. The glutamic acid fermentation broth concentration steam recovery system disclosed in this invention has a simple connection structure and is easy to implement. It effectively recovers the steam and separates it into concentrated ammonia water and condensate with low ammonia nitrogen content through the deammoniation tower, avoiding direct discharge and environmental pollution.

[0027] 2. The method for recovering and utilizing concentrated steam from glutamic acid fermentation broth disclosed in this invention discloses that part of the obtained concentrated ammonia water is used to adjust the pH of the glutamic acid fermentation medium, and another part is used for power plant flue gas desulfurization. The condensate water is used for glutamic acid feedstock fermentation, achieving zero wastewater discharge and simultaneously realizing the recovery and utilization of water resources and concentrated ammonia water, thereby reducing the cost of glutamic acid production.

[0028] 3. The recycling method of the glutamic acid fermentation broth concentration steam recovery system disclosed in this invention discloses that the condensate is used for the fermentation of glutamic acid, and the concentrated ammonia is used to adjust the pH of the glutamic acid fermentation medium to avoid the formation of precipitates in the medium, ensure complete sterilization of the fermentation medium, and ensure that its nutrient concentration is normal, thereby improving fermentation indicators; at the same time, it reduces the amount of liquid nitrogen used and reduces production costs.

[0029] 4. The recycling method of the glutamic acid fermentation broth concentration steam recovery system disclosed in this invention uses a portion of the concentrated ammonia water obtained to adjust the pH of the glutamic acid fermentation medium, thereby avoiding ammonia pollution in the feed preparation area and ensuring the health of the staff. Attached image description:

[0030] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention.

[0031] Figure 2 This is a diagram illustrating the preparation of the fermentation medium in this invention; wherein... Figure 2 (a) shows the fermentation medium conditions in Example 7. Figure 2 (b) shows the fermentation medium conditions in Example 8. Figure 2 (c) shows the fermentation medium conditions for Comparative Example 1. Figure 2 (d) shows the fermentation medium conditions for Comparative Example 3. Figure 2 (e) shows the fermentation medium conditions of Comparative Example 4.

[0032] Figure 3 This is a diagram showing the contamination status of the fermentation medium in this invention; wherein... Figure 3 (a) shows the contamination status of the fermentation medium in Example 7. Figure 3 (b) shows the contamination status of the fermentation medium in Example 8. Figure 3 (c) shows the contamination status of the fermentation medium in Comparative Example 1. Figure 3 (d) shows the contamination status of the fermentation medium in Comparative Example 3. Figure 2 (e) shows the contamination status of the fermentation medium in Comparative Example 4.

[0033] 1. Ammonia vapor pipeline, 2. Primary water pipeline, 3. Ammonia removal tower, 4. Condenser, 5. Condensate storage tank, 6. Concentrated ammonia storage tank, 7. Cooler, 8. Ammonia density meter. Detailed implementation method:

[0034] The present invention will be further described in detail below through embodiments.

[0035] Example 1: As Figure 1 As shown, a glutamic acid fermentation broth concentration steam recovery system includes an ammonia-containing steam pipeline 1, a primary water pipeline 2, an ammonia removal tower 3, a condenser 4, a condensate storage tank 5, a concentrated ammonia storage tank 6, a cooler 7, and an ammonia density meter 8. The outlet of the ammonia-containing steam pipeline 1 is connected to the inlet of the ammonia removal tower 3, and the outlet of the primary water pipeline is connected to the spray water inlet of the ammonia removal tower 3. The top outlet of the ammonia removal tower 3 is connected to the inlet of the condenser 4, and the outlet of the condenser 4 is connected to the inlet of the condensate storage tank 5. The bottom outlet of the ammonia removal tower 3 is connected to the inlet of the concentrated ammonia storage tank 6. Direct discharge is avoided to prevent environmental pollution.

[0036] The bottom outlet of the ammonia stripping tower 3 is connected to the inlet of the cooler 7, and the outlet of the cooler 7 is connected to the inlet of the ammonia stripping tower 3. An ammonia density meter 8 is installed at the bottom outlet of the ammonia stripping tower 3. A first control valve is installed on the pipeline between the ammonia stripping tower 3 and the cooler 7, and a second control valve is installed on the pipeline between the ammonia stripping tower 3 and the concentrated ammonia storage tank 6. The system connection structure of this invention is simple and easy to implement.

[0037] Example 2: A method for recovering concentrated steam from glutamic acid fermentation broth using the system described in Example 1, comprising the following steps: (1) ammonia absorption; (2) condensation;

[0038] (1) Ammonia absorption: Ammonia-containing vapor enters the lower part of the ammonia removal tower 3 with an internal pressure of 340-360 mbar, and primary water at 15-20°C is sprayed downward from the upper part of the ammonia removal tower 3; the ammonia in the ammonia-containing vapor gradually dissolves in the primary water, and the ammonia water falls to the bottom of the ammonia removal tower 3.

[0039] The ammonia water is cooled to 10-12°C in cooler 7, and then sent to the middle section of the ammonia removal tower 3 to continue absorbing ammonia from the ammonia-containing vapor. The ammonia water density meter 8 displays a density value of 0.91-0.94 g / cm³. 3 At that time, close the first control valve and open the second control valve to pump concentrated ammonia into the concentrated ammonia storage tank 6.

[0040] (2) Condensation: The vapor after ammonia removal in step (1) is discharged from the top outlet of the deammoniation tower 3 and enters the condenser 4, where it is condensed and liquefied into condensate with a pH of 9-9.5.

[0041] The condensate is used for the fermentation of glutamic acid, and part of the concentrated ammonia is used to adjust the pH of the glutamic acid fermentation medium, while the other part is used for desulfurization of flue gas in power plants.

[0042] Example 3: A method for fermenting glutamic acid feedstock and adjusting the pH of the fermentation medium using the condensate and concentrated ammonia water described in Example 2, specifically including the following steps: (1) pretreatment; (2) continuous sterilization; (3) preparation of fermentation medium; (4) pH adjustment; (5) glutamic acid fermentation;

[0043] (1) Pretreatment: Add 20-25% of the condensed water to the mixing tank A by mass percentage, then add 8-10% corn steep liquor, 0.8-1.5% soybean meal hydrolysate, and 0.3-0.9% molasses, and mix evenly to form material A; then add 8-12% of the condensed water to the mixing tank B by mass percentage, heat to 45-55℃, then add 0.2-0.5% potassium chloride, 0.1-0.4% magnesium sulfate, 0.1-0.4% betaine, 0.001-0.002% ferrous sulfate, 0.001-0.002% manganese sulfate, and 0.001-0.002% zinc sulfate, and mix evenly to form material B;

[0044] (2) Continuous sterilization: The materials A and B in step (1) are continuously sterilized at a temperature of 125-127℃ for 20-25 minutes, and then cooled to 32-35℃.

[0045] (3) Prepare fermentation medium: Add 15% of the condensed water, 8% of the glucose solution with a concentration of 33-36%, 30% of the material A sterilized in step (2), 4% of the condensed water, 8% of the material B sterilized in step (2) and 18% of the condensed water into the fermenter in sequence according to the mass percentage to obtain a fermentation medium with a pH of 3.0-3.5;

[0046] (4) Adjust pH: Add liquid ammonia to the fermentation medium in step (3) to adjust the pH to 7.0;

[0047] (5) Glutamic acid fermentation: The temperature-sensitive Corynebacterium glutamicum seed culture with an OD value of at least 1.0 is inoculated into the fermentation medium with a pH of 7.0 in step (4) and fermented for 32 hours; the volume of the inoculated temperature-sensitive Corynebacterium glutamicum seed culture accounts for 10%-15% of the volume of the fermentation medium.

[0048] Example 4: A method for fermenting glutamic acid feedstock and adjusting the pH of the fermentation medium using the condensate and concentrated ammonia water described in Example 2, specifically including the following steps: (1) pretreatment; (2) continuous sterilization; (3) preparation of fermentation medium; (4) pH adjustment; (5) glutamic acid fermentation;

[0049] (1) Pretreatment: Add 20-25% of the condensed water to the mixing tank A by mass percentage, then add 8-10% corn steep liquor, 0.8-1.5% soybean meal hydrolysate, and 0.3-0.9% molasses, and mix evenly to form material A; then add 8-12% of the condensed water to the mixing tank B by mass percentage, heat to 45-55℃, then add 0.2-0.5% potassium chloride, 0.1-0.4% magnesium sulfate, 0.1-0.4% betaine, 0.001-0.002% ferrous sulfate, 0.001-0.002% manganese sulfate, and 0.001-0.002% zinc sulfate, and mix evenly to form material B;

[0050] (2) Continuous sterilization: The materials A and B in step (1) are continuously sterilized at a temperature of 125-127℃ for 20-25 minutes, and then cooled to 32-35℃.

[0051] (3) Preparation of fermentation medium: 23% of the condensate, 12% of the glucose solution with a concentration of 33-36%, 37% of the material A sterilized in step (2), 6% of the condensate, 12% of the material B sterilized in step (2) and 22% of the condensate are sequentially added into the fermenter according to the mass percentage to obtain a fermentation medium with a pH of 3.0-3.5;

[0052] (4) Adjust pH: Add liquid ammonia to the fermentation medium in step (3) to adjust the pH to 7.0;

[0053] (5) Glutamic acid fermentation: The temperature-sensitive Corynebacterium glutamicum seed culture with an OD value of at least 1.0 is inoculated into the fermentation medium with a pH of 7.0 in step (4) and fermented for 32 hours; the volume of the inoculated temperature-sensitive Corynebacterium glutamicum seed culture accounts for 10%-15% of the volume of the fermentation medium.

[0054] Example 5: A method for fermenting glutamic acid feedstock and adjusting the pH of the fermentation medium using the condensate and concentrated ammonia water described in Example 2, specifically including the following steps: (1) pretreatment; (2) continuous sterilization; (3) preparation of fermentation medium; (4) pH adjustment; (5) glutamic acid fermentation;

[0055] (1) Pretreatment: Add 20-25% of the condensed water to the mixing tank A by mass percentage, then add 8-10% corn steep liquor, 0.8-1.5% soybean meal hydrolysate, and 0.3-0.9% molasses, and mix evenly to form material A; then add 8-12% of the condensed water to the mixing tank B by mass percentage, heat to 45-55℃, then add 0.2-0.5% potassium chloride, 0.1-0.4% magnesium sulfate, 0.1-0.4% betaine, 0.001-0.002% ferrous sulfate, 0.001-0.002% manganese sulfate, and 0.001-0.002% zinc sulfate, and mix evenly to form material B;

[0056] (2) Continuous sterilization: The materials A and B in step (1) are continuously sterilized at a temperature of 125-127℃ for 20-25 minutes, and then cooled to 32-35℃.

[0057] (3) Prepare fermentation medium: According to the mass percentage, 20% of the condensate, 10% of the glucose solution with a concentration of 33-36%, 35% of the material A sterilized in step (2), 5% of the condensate, 10% of the material B sterilized in step (2) and 20% of the condensate are sequentially added into the fermenter to obtain a fermentation medium with a pH of 3.0-3.5;

[0058] (4) Adjust pH: Add liquid ammonia to the fermentation medium in step (3) to adjust the pH to 7.0;

[0059] (5) Glutamic acid fermentation: The temperature-sensitive Corynebacterium glutamicum seed culture with an OD value of at least 1.0 is inoculated into the fermentation medium with a pH of 7.0 in step (4) and fermented for 32 hours; the volume of the inoculated temperature-sensitive Corynebacterium glutamicum seed culture accounts for 10%-15% of the volume of the fermentation medium.

[0060] Example 6: A method for fermenting glutamic acid feedstock and adjusting the pH of the fermentation medium using the condensate and concentrated ammonia water described in Example 2, specifically including the following steps: (1) pretreatment; (2) continuous sterilization; (3) preparation of fermentation medium; (4) pH adjustment; (5) glutamic acid fermentation;

[0061] (1) Pretreatment: Add 20-25% primary water to batching tank A by mass percentage, then add 8-10% corn steep liquor, 0.8-1.5% soybean meal hydrolysate, and 0.3-0.9% molasses, and mix evenly to form material A; then add 8-12% primary water to batching tank B by mass percentage, heat to 45-55℃, then add 0.2-0.5% potassium chloride, 0.1-0.4% magnesium sulfate, 0.1-0.4% betaine, 0.001-0.002% ferrous sulfate, 0.001-0.002% manganese sulfate, and 0.001-0.002% zinc sulfate, and mix evenly to form material B;

[0062] (2) Continuous sterilization: The materials A and B in step (1) are continuously sterilized at a temperature of 125-127℃ for 20-25 minutes, and then cooled to 32-35℃.

[0063] (3) Prepare fermentation medium: According to the mass percentage, 20% of the condensate, 10% of the glucose solution with a concentration of 33-36%, 35% of the material A sterilized in step (2), 5% of the condensate, 10% of the material B sterilized in step (2) and 20% of the condensate are sequentially added into the fermenter to obtain a fermentation medium with a pH of 3.0-3.5;

[0064] (4) Adjust pH: Add liquid ammonia to the fermentation medium in step (3) to adjust the pH to 7.0;

[0065] (5) Glutamic acid fermentation: The temperature-sensitive Corynebacterium glutamicum seed culture with an OD value of at least 1.0 is inoculated into the fermentation medium with a pH of 7.0 in step (4) and fermented for 32 hours; the volume of the inoculated temperature-sensitive Corynebacterium glutamicum seed culture accounts for 10%-15% of the volume of the fermentation medium.

[0066] Example 7: The difference between this example and Example 5 is that step (3) of preparing the fermentation medium also includes the following method: 20% of the condensate, 10% of the glucose solution with a concentration of 33-36%, 35% of the material A sterilized in step (2), 5% of the condensate, 10% of the material B sterilized in step (2) and 20% of the concentrated ammonia water are sequentially added into the fermenter according to the mass percentage to obtain a fermentation medium with a pH of 4.5-5.0. Since the fermenter is a closed container, there is no problem of ammonia leakage, which is harmless to the staff and ensures the health of the staff.

[0067] Example 8: The difference between this example and Example 6 is that step (3) of preparing the fermentation medium also includes the following method: 20% primary water, 10% glucose solution with a concentration of 33-36%, 35% of the material A sterilized in step (2), 5% primary water, 10% of the material B sterilized in step (2) and 20% of the concentrated ammonia water are sequentially added into the fermenter according to the mass percentage to obtain a fermentation medium with a pH of 4.0-4.5. Since the fermenter is a closed container, there is no problem of ammonia leakage, which is harmless to the staff and ensures the health of the staff.

[0068] Comparative Example 1: The glutamic acid fermentation broth was concentrated and condensed into condensate using condenser 4. The condensate was then used to replace the primary water for fermentation feed preparation and fermentation culture medium preparation. The specific steps included: (1) pretreatment; (2) continuous sterilization; (3) preparation of fermentation culture medium; (4) pH adjustment; (5) glutamic acid fermentation.

[0069] (1) Pretreatment: Add 20-25% of the condensed water to the mixing tank A by mass percentage, then add 8-10% corn steep liquor, 0.8-1.5% soybean meal hydrolysate, and 0.3-0.9% molasses, and mix evenly to form material A; then add 8-12% of the condensed water to the mixing tank B by mass percentage, heat to 45-55℃, then add 0.2-0.5% potassium chloride, 0.1-0.4% magnesium sulfate, 0.1-0.4% betaine, 0.001-0.002% ferrous sulfate, 0.001-0.002% manganese sulfate, and 0.001-0.002% zinc sulfate, and mix evenly to form material B.

[0070] Since both batching tank A and batching tank B are open tanks, a large amount of ammonia in the condensate will evaporate, thus contaminating the batching area with ammonia and seriously affecting the health of the workers.

[0071] (2) Continuous sterilization: The materials A and B in step (1) are continuously sterilized at a temperature of 125-127℃ for 20-25 minutes, and then cooled to 32-35℃.

[0072] (3) Prepare fermentation medium: Add 20% condensed water, 10% glucose solution with a concentration of 33-36%, 35% of the material A sterilized in step (2), 5% of the condensed water, 10% of the material B sterilized in step (2) and 20% condensed water into the fermenter in sequence according to the mass percentage to obtain a fermentation medium with a pH of 7.0-8.0. There is no need to adjust the pH with liquid nitrogen.

[0073] (4) Glutamic acid fermentation: The temperature-sensitive Corynebacterium glutamicum seed culture with an OD value of at least 1.0 is inoculated into the fermentation medium with a pH of 7.0 in step (4) and fermented for 32 hours; the volume of the inoculated temperature-sensitive Corynebacterium glutamicum seed culture accounts for 10%-15% of the volume of the fermentation medium.

[0074] Comparative Example 2: The fermentation materials and fermentation medium were prepared directly using primary water, specifically including the following steps: (1) pretreatment; (2) continuous sterilization; (3) preparation of fermentation medium; (4) pH adjustment; (5) glutamic acid fermentation;

[0075] (1) Pretreatment: Add 20-25% of the primary water to the mixing tank A by mass percentage, then add 8-10% corn steep liquor, 0.8-1.5% soybean meal hydrolysate, and 0.3-0.9% molasses, and mix evenly to form material A; then add 8-12% of the primary water to the mixing tank B by mass percentage, heat to 45-55℃, then add 0.2-0.5% potassium chloride, 0.1-0.4% magnesium sulfate, 0.1-0.4% betaine, 0.001-0.002% ferrous sulfate, 0.001-0.002% manganese sulfate, and 0.001-0.002% zinc sulfate, and mix evenly to form material B.

[0076] Since both batching tank A and batching tank B are open tanks, a large amount of ammonia in the condensate will evaporate, thus contaminating the batching area with ammonia and seriously affecting the health of the workers.

[0077] (2) Continuous sterilization: The materials A and B in step (1) are continuously sterilized at a temperature of 125-127℃ for 20-25 minutes, and then cooled to 32-35℃.

[0078] (3) Prepare fermentation medium: Add 20% primary water, 10% glucose solution with a concentration of 33-36%, 35% of material A sterilized in step (2), 5% primary water, 10% of material B sterilized in step (2) and 20% primary water into the fermenter in sequence according to the mass percentage to obtain a fermentation medium with a pH of 2.5-3.0;

[0079] (4) Adjust pH: Add liquid ammonia to the fermentation medium in step (3) to adjust the pH to 7.0;

[0080] (5) Glutamic acid fermentation: The temperature-sensitive Corynebacterium glutamicum seed culture with an OD value of at least 1.0 is inoculated into the fermentation medium with a pH of 7.0 in step (4) and fermented for 32 hours; the volume of the inoculated temperature-sensitive Corynebacterium glutamicum seed culture accounts for 10%-15% of the volume of the fermentation medium.

[0081] Comparative Example 3: Concentrated ammonia water was used instead of primary water for fermentation ingredient preparation and fermentation culture medium preparation. The specific steps included: (1) pretreatment; (2) continuous sterilization; (3) preparation of fermentation culture medium; (4) pH adjustment; (5) glutamic acid fermentation.

[0082] (1) Pretreatment: Add 20-25% of the concentrated ammonia solution to the mixing tank A by mass percentage, then add 8-10% corn steep liquor, 0.8-1.5% soybean meal hydrolysate, and 0.3-0.9% molasses, and mix evenly to form material A; then add 8-12% of the concentrated ammonia solution to the mixing tank B by mass percentage, heat to 45-55℃, then add 0.2-0.5% potassium chloride, 0.1-0.4% magnesium sulfate, 0.1-0.4% betaine, 0.001-0.002% ferrous sulfate, 0.001-0.002% manganese sulfate, and 0.001-0.002% zinc sulfate, and mix evenly to form material B.

[0083] Since both batching tank A and batching tank B are open tanks, a large amount of ammonia in the condensate will evaporate, thus contaminating the batching area with ammonia and seriously affecting the health of the workers.

[0084] (2) Continuous sterilization: The materials A and B in step (1) are continuously sterilized at a temperature of 125-127℃ for 20-25 minutes, and then cooled to 32-35℃.

[0085] (3) Prepare fermentation medium: Add 20% concentrated ammonia, 10% glucose solution with a concentration of 33-36%, 35% of the material A sterilized in step (2), 5% of the concentrated ammonia, 10% of the material B sterilized in step (2) and 20% concentrated ammonia into the fermenter in sequence according to the mass percentage to obtain a fermentation medium with a pH of 7.0-8.0. There is no need to adjust the pH with liquid nitrogen.

[0086] (4) Glutamic acid fermentation: The temperature-sensitive Corynebacterium glutamicum seed culture with an OD value of at least 1.0 is inoculated into the fermentation medium with a pH of 7.0 in step (4) and fermented for 32 hours; the volume of the inoculated temperature-sensitive Corynebacterium glutamicum seed culture accounts for 10%-15% of the volume of the fermentation medium.

[0087] Comparative Example 4: The difference between this comparative example and Example 6 is that step (3) of preparing the fermentation medium also includes the following method: 20% concentrated ammonia water, 10% glucose solution with a concentration of 33-36%, 35% of the material A sterilized in step (2), 5% concentrated ammonia water, 10% of the material B sterilized in step (2) and 20% of the concentrated ammonia water are sequentially added into the fermenter according to the mass percentage to obtain a fermentation medium with a pH of 5.0-6.0. Since the fermenter is a closed container, there is no problem of ammonia leakage, which is harmless to the staff and ensures the health of the staff.

[0088] Comparative Example 5: The difference between this comparative example and Example 6 is that step (3) of preparing the fermentation medium also includes the following method: 20% concentrated ammonia water, 10% glucose solution with a concentration of 33-36%, 35% of the material A sterilized in step (2), 5% primary water, 10% of the material B sterilized in step (2) and 20% primary water are sequentially added into the fermenter according to the mass percentage to obtain a fermentation medium with a pH of 5.0-6.0. Since the fermenter is a closed container, there is no problem of ammonia leakage, which is harmless to the staff and ensures the health of the staff.

[0089] 1. Determination of fermentation indicators: Fermentation indicators of Examples 5-8 and Comparative Examples 1-4 were determined, and the acid production rate and conversion rate of their fermentation broth were measured; the results are shown in Table 1 below.

[0090] Table 1 Fermentation Indicators

[0091]

[0092] In this invention, Example 7 showed the highest acid production rate and conversion rate, and the amount of liquid ammonia used was less than that of Comparative Example 2. Examples 5, 6, and 8 showed higher acid production rates and conversion rates than Comparative Examples 1-5, and the amount of liquid ammonia used was at most 25t, which was not increased. Therefore, the process method disclosed in this invention for using condensate and concentrated ammonia in the fermentation of glutamic acid and adjusting the pH of the fermentation medium can effectively realize the recovery of condensate and concentrated ammonia, while ensuring the normal fermentation of glutamic acid.

[0093] 2. Precipitation detection: 100 mL of fermentation medium from Examples 7-8 and Comparative Examples 1, 3, and 4 were weighed and placed in weighing cups, allowed to stand, and then photographed. Figure 2 (a) shows the fermentation medium conditions in Example 7. Figure 2 (b) shows the fermentation medium conditions in Example 8. Figure 2 (c) shows the fermentation medium conditions for Comparative Example 1. Figure 2 (d) shows the fermentation medium conditions for Comparative Example 3. Figure 2(e) shows the fermentation medium conditions of Comparative Example 4; it can be seen from the figure that Comparative Examples 1, 3 and 4 clearly produced precipitation; while Examples 7 and 8 did not.

[0094] 3. Sterilization test: In a sterile environment, the fermentation media of Examples 7-8 and Comparative Examples 1, 3, and 4 were placed on sterile plates and incubated at 37°C for 24 hours before observation and photography. Figure 3 (a) shows the contamination status of the fermentation medium in Example 7. Figure 3 (b) shows the contamination status of the fermentation medium in Example 8. Figure 3 (c) shows the contamination status of the fermentation medium in Comparative Example 1. Figure 3 (d) shows the contamination status of the fermentation medium in Comparative Example 3. Figure 3 (e) shows the contamination status of the fermentation medium in Comparative Example 4; it can be seen from the figure that there are white colonies on the fermentation mediums of Comparative Example 1, Comparative Example 3 and Comparative Example 4, while there are no colonies on the fermentation mediums of Example 7 and Example 8; indicating that the precipitation in Comparative Example 1, Comparative Example 3 and Comparative Example 4 affects the sterilization of the fermentation medium and cannot completely sterilize it.

[0095] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A glutamic acid fermentation broth concentration and steam recovery system, characterized in that, It includes an ammonia-containing vapor pipeline, a primary water pipeline, an ammonia removal tower, a condenser, a condensate storage tank, a concentrated ammonia storage tank, a cooler, and an ammonia density meter; the outlet of the ammonia-containing vapor pipeline is connected to the inlet of the ammonia removal tower, and the outlet of the primary water pipeline is connected to the spray water inlet of the ammonia removal tower; the top outlet of the ammonia removal tower is connected to the inlet of the condenser, and the outlet of the condenser is connected to the inlet of the condensate storage tank; the bottom outlet of the ammonia removal tower is connected to the inlet of the concentrated ammonia storage tank. The bottom outlet of the ammonia removal tower is connected to the inlet of the cooler, and the outlet of the cooler is connected to the inlet of the ammonia removal tower; an ammonia density meter is installed at the bottom outlet of the ammonia removal tower; a first control valve is installed on the pipeline between the ammonia removal tower and the cooler; and a second control valve is installed on the pipeline between the ammonia removal tower and the concentrated ammonia storage tank. The method for recovering concentrated steam from glutamic acid fermentation broth using the above system includes the following steps: (1) ammonia absorption; (2) condensation; (1) Ammonia absorption: Ammonia-containing vapor enters the lower part of the ammonia removal tower with an internal pressure of 340-360 mbar, and primary water at 15-20°C is sprayed downward from the top of the ammonia removal tower; the ammonia in the ammonia-containing vapor gradually dissolves in the primary water, and the ammonia water falls to the bottom of the ammonia removal tower. The ammonia water is cooled to 10-12°C in a cooler and then sent to the middle section of the ammonia removal tower to continue absorbing ammonia from the ammonia-containing vapor. The process continues until the ammonia water density meter displays a density value of 0.91-0.94 g / cm³. 3 At that time, close the first control valve, open the second control valve, and pump concentrated ammonia into the concentrated ammonia storage tank; (2) Condensation: The steam after ammonia removal in step (1) is discharged from the top outlet of the deammoniation tower and enters the condenser, where it is condensed and liquefied into condensate with a pH of 9-9.

5. The condensate is used for the fermentation of glutamic acid, and part of the concentrated ammonia is used to adjust the pH of the fermentation medium of glutamic acid, while the other part is used for desulfurization of flue gas in power plants.

2. The glutamic acid fermentation broth concentration and steam recovery system according to claim 1, characterized in that, The specific process for applying the condensate and concentrated ammonia to the fermentation of glutamic acid and adjusting the pH of the fermentation medium includes the following steps: (1) pretreatment; (2) continuous sterilization; (3) preparation of fermentation medium; (4) pH adjustment; (5) glutamic acid fermentation; (1) Pretreatment: Add 20-25% of the condensed water or primary water to the mixing tank A by mass percentage, then add 8-10% corn syrup, 0.8-1.5% soybean meal hydrolysate, and 0.3-0.9% molasses, and mix evenly to form material A; then add 8-12% of the condensed water or primary water to the mixing tank B by mass percentage, heat to 45-55℃, then add 0.2-0.5% potassium chloride, 0.1-0.4% magnesium sulfate, 0.1-0.4% betaine, 0.001-0.002% ferrous sulfate, 0.001-0.002% manganese sulfate, and 0.001-0.002% zinc sulfate, and mix evenly to form material B; (2) Continuous sterilization: The materials A and B in step (1) are continuously sterilized at a temperature of 125-127℃ for 20-25 minutes, and then cooled to 32-35℃; (3) Prepare fermentation medium: Add 15-23% of the condensate, 8-12% of the low sugar, 30-37% of the material A sterilized in step (2), 4-6% of the condensate, 8-12% of the material B sterilized in step (2) and 18-22% of the condensate into the fermenter in sequence according to the mass percentage to obtain a fermentation medium with a pH of 3.0-3.5; (4) Adjust pH: Add liquid ammonia to the fermentation medium in step (3) to adjust the pH to 7.0; (5) Glutamic acid fermentation: The temperature-sensitive Corynebacterium glutamicum seed liquid with an OD value of at least 1.0 is inoculated into the fermentation medium with a pH of 7.0 in step (4) and fermented for 32 hours; the volume of the inoculated temperature-sensitive Corynebacterium glutamicum seed liquid accounts for 10%-15% of the volume of the fermentation medium.

3. The glutamic acid fermentation broth concentration and steam recovery system according to claim 2, characterized in that, Step (3) of preparing the fermentation medium also includes the following methods: According to the mass percentage, 15-23% primary water, 8-12% low sugar, 33-37% of the material A sterilized in step (2), 4-6% primary water, 8-12% of the material B sterilized in step (2), and 18-22% of the concentrated ammonia water are sequentially added into the fermenter to obtain a fermentation medium with a pH of 4.0-4.

5.

4. The glutamic acid fermentation broth concentration and steam recovery system according to claim 2, characterized in that, Step (3) of preparing the fermentation medium also includes the following methods: According to the mass percentage, 15-23% of the condensate, 8-12% of the low sugar, 33-37% of the material A sterilized in step (2), 4-6% of the condensate, 8-12% of the material B sterilized in step (2), and 18-22% of the concentrated ammonia water are sequentially added into the fermenter to obtain a fermentation medium with a pH of 4.5-5.

0.

5. A glutamic acid fermentation broth concentration and steam recovery system according to any one of claims 2-4, characterized in that, The low sugar in step (3) is a glucose solution with a concentration of 33-36%.

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