252 results about "Acid production" patented technology

The invention belongs to the technical field of flue gas acid making, and particularly discloses an acid making fan outlet pressure soft measurement method based on LSTM (Long Short Term Memory), which comprises the following steps of: performing cleaning, down-sampling and normalization processing on fan inlet and outlet pressure original data; based on a time sequence analysis technology, extracting input features in the preprocessed data; an LSTM network is adopted to establish a soft measurement model, and long-term dependence characteristics in a time sequence are captured through a gating mechanism; performing training optimization on model hyper-parameters through grid search; and the model evaluates and predicts the performance by using the data of the test set, deploys the qualified model to an industrial control system, and predicts, regulates and controls the outlet pressure of the acid making fan in real time. According to the method, soft measurement and LSTM are combined, long-term dependency and dynamic change information in a time sequence are extracted, weighting processing is carried out on different scale features to improve prediction precision, real-time prediction of multi-step variables is achieved, and the method has the advantages of being high in prediction precision, high in timeliness and low in hardware cost.

The invention discloses a Weissella sinus strain for improving the fermentation flavor of American ginseng and application of the Weissella sinus strain. According to the present invention, through the comprehensive evaluation of a variety of lactic acid bacteria, including the acid production capacity, the chroma regulation and the flavor characteristic analysis, the optimal strain for the American ginseng fermentation is finally screened, and the strain shows the significant flavor regulation advantage. On one hand, characteristic earthy smell substances of American ginseng can be completely degraded, and the bad flavor of the raw materials is effectively improved; on the other hand, a compound with a fruity flavor characteristic can be specifically generated, and a fermentation product is endowed with a remarkable fragrant and sweet flavor. In addition, the strain disclosed by the invention maintains proper acid production capacity and chroma stability, and the flavor quality is remarkably improved on the premise of ensuring the fermentation efficiency. Due to the characteristics, the strain becomes an ideal fermentation strain for developing a high-quality fermented American ginseng product.

The invention relates to the field of sludge circulation treatment, in particular to a sludge circulation treatment method capable of reducing pollution and carbon. The sludge circulation treatment method capable of reducing pollution and carbon comprises the following treatment steps: S1, sludge disintegration: selecting a sludge sample in sewage, and screening out dominant bacteria and reproduction conditions; s2, anaerobic digestion treatment: adding the screened strains into a sludge anaerobic digestion device for anaerobic digestion treatment; s3, sewage treatment: conveying the sewage subjected to anaerobic digestion treatment into a sewage treatment device, and selecting organic matters dissolved out of sludge in the step of anaerobic digestion treatment as a denitrification carbon source for biological treatment. According to the present invention, the sludge digestion innovative process is adopted, the original anaerobic reaction process in the sewage process is utilized, the decomposition and acidification effects on the biochemical excess sludge are enhanced, the methanogenesis reaction is inhibited through the internal ammonia nitrogen, the dissolution acid production efficiency is improved, the reaction time is shortened, and the on-site resource utilization of the sludge is achieved.

The invention relates to the technical field of bio-organic fertilizer fermentation monitoring, in particular to a bacillus bio-organic fertilizer fermentation condition monitoring and optimizing method. The method comprises the steps of obtaining a data change degree characterization value and a related difference characterization value of a first detection point, obtaining a target bacillus acid production characterization value of the first detection point according to the data change degree characterization value and the related difference characterization value of the first detection point, and obtaining a target bacillus acid production characterization value of the second detection point according to the target bacillus acid production characterization value. Screening the first detection point again, obtaining a predicted PH value at a future monitoring moment according to a screening result, and monitoring the fermentation process of the bacillus bio-organic fertilizer according to the predicted PH value at the future monitoring moment. And the timeliness or timeliness of monitoring the pH value of the fermentation liquid in the fermentation tank can be improved by predicting the pH value.

The invention discloses a method and a system for efficiently producing short-chain fatty acid by utilizing waste molasses in the sugar industry and municipal sludge through synergistic anaerobic fermentation, and belongs to the technical field of organic solid waste recycling. Waste molasses and municipal sludge are mixed according to a specific ratio, the carbon-nitrogen ratio is optimized to 20-30: 1, trace metal catalysts (Fe < 2 + >, Co < 2 + > and Ni < 2 + >) are added, and two-stage pH regulation (the initial pH is 6.0-7.0, and the later pH is 5.5-6.0) and a medium-temperature (35-37 DEG C) anaerobic fermentation process are combined, so that the yield of short-chain fatty acid is remarkably increased to 5.2-6.8 g COD / L and is increased by 200-300% compared with that of traditional sludge single-substrate fermentation. The method realizes recycling and high-value conversion of the organic solid waste, and has the characteristics of low cost, high acid production efficiency and environmental friendliness.

The invention discloses Pediococcus pentosaceus G41, which is separated from rumen fluid of healthy adult dairy cows in a certain cattle farm in Changchun, has the advantages of high growth speed and strong acid production capacity, and can effectively relieve cholestatic liver injury. Experiments prove that the Pediococcus pentosaceus G41 reduces the activity of serum AST, ALT and GDH of a mouse with cholestatic liver injury, reduces the content of total bile acid in blood and liver, increases the content of total bile acid in excrement, and improves cholestatic and dirty injury caused by cholestatic.

The invention discloses a fermentation production process for improving the conversion rate of L-arginine and a strain used by the fermentation production process, and belongs to the technical field of fermentation engineering. According to the method, the content of residual sugar and ammonia nitrogen in the fermentation process of the L-arginine is accurately regulated and controlled, so that the growth speed of thalli and the sugar-acid conversion capacity are controlled, the fermentation period is shortened, meanwhile, the fermentation period of the L-arginine is 44-55 hours, the produced acid reaches 130 g / L or above, and the conversion rate is 50% or above by supplementing materials in the fermentation process and controlling other processes. According to the process, the acid production and conversion rate of the strain are greatly improved, and the production cost is reduced.

The invention provides fermented lactobacillus mucus BL-SWN1 and application thereof, the fermented lactobacillus mucus BL-SWN1 is screened from naturally fermented soybean clear water, is preserved in China General Microbiological Culture Collection Center (CGMCC) on January 6, 2025, is named as Limosilicilla fermentum in taxonomy, has a preservation number of CGMCC No.33307, and belongs to the technical field of microorganisms. The lactobacillus mucus BL-SWN1 has good acid production capacity, gastrointestinal fluid and cholate tolerance, bacteriostatic activity and nitrite degradation capacity, the pH value of a culture medium can be reduced to about 4.3 within 24 h of culture, and the nitrite degradation rate reaches 95% or above. The fermentation lactobacillus mucus BL-SWN1 can be applied to vegetable fermentation products such as pickled Chinese cabbages and pickled vegetables, can also be suitable for the fermentation process of dairy products and meat products, has a wide application prospect in the food industry, and particularly has remarkable advantages in the aspect of development of healthy fermentation foods.

The utility model discloses a system for realizing online circulating flow and fermentation of amino acid by adopting a ceramic membrane, which comprises a strain tank, a seed tank arranged on one side of the strain tank, a fermentation tank arranged on one side of the seed tank, a feed pump arranged at the top end of one side of the fermentation tank, a cleaning tank arranged on one side of the fermentation tank, and a circulating pump arranged at the bottom end of one side of the cleaning tank. According to the amino acid on-line circulating flow and fermentation system realized by adopting the ceramic membrane, the culture times of early-stage strain culture and seed tank culture are obviously reduced; the fermentation level is always in a high level state, the acid production rate of thalli is high, the yield is remarkably improved under the condition that equipment is not increased, and the total yield even can reach 2-3 times of the original yield; nutrient substances in the ceramic membrane filtrate can be sterilized after being extracted to serve as nutrient substances to be fed into the fermentation tank, so that the product output ratio of feeding is increased, namely the acid yield is increased; and the ceramic membrane can be sterilized by steam, so that the requirement of sterile equipment is met.

The invention discloses a microorganism, a microbial agent, food, a method for preparing the food and a method for producing pectinase, and relates to the field of microorganisms. The microorganism is plant lactobacillus, and the preservation number of the microorganism is CGMCC (China General Microbiological Culture Collection Center) No.31283. The new strain of the plant lactobacillus obtained through screening has the advantages of being high in growth speed, high in acid production capacity, acid resistance and salt resistance, high in pectinase production capacity, high in nitrite and nitrate metabolism capacity and the like; the new strain is used for developing salt-reduced fermented food, the process adaptability is good, and the prepared fermented food is rich in lactic acid bacteria content, nutritional, healthy and unique in flavor; a food fermentation process developed by utilizing the new strain is high in fermentation efficiency, short in production period and high in application value.

The invention relates to the technical field of chemical equipment, and provides a tetrazoleacetic acid production system which comprises a glycine tank, a triethanol orthoformate tank, a glacial acetic acid tank, a regulating liquid tank, a pretreatment kettle, a refining reaction kettle and a nitrogen displacement device, a feeding mechanism for feeding sodium azide is arranged at the upper end of the refining reaction kettle, and a nitrogen replacement pipe of the nitrogen replacement device can be alternatively communicated with the feeding mechanism or the refining reaction kettle; when the sodium azide is fed, the nitrogen replacement pipe is communicated with the feeding mechanism, and the feeding mechanism can enable the sodium azide to enter the refining reaction kettle under the pushing of nitrogen; according to the invention, the feeding of sodium azide can be combined with the nitrogen replacement device through the feeding mechanism, the feeding work of sodium azide is driven by nitrogen, manual feeding is eliminated in the production system, and the convenience and safety are improved.

The invention discloses a sludge anaerobic acidogenesis strengthening method based on pyrohydrolysis and potassium permanganate synergistic degradation of melanoids. The method comprises the following steps: (1) screening sludge to remove impurities, and then carrying out gravity settling concentration; (2) pyrohydrolysis treatment: high-temperature and high-pressure treatment, pressure relief and cooling; (3) adding potassium permanganate for oxidation, and performing ultrasonic dispersion; (4) anaerobic fermentation: inoculating activated sludge, and controlling fermentation conditions; and (5) separating and extracting the short-chain fatty acid. Through the synergistic effect of pyrohydrolysis and potassium permanganate, melanoids generated in the pyrohydrolysis process are degraded in a targeted mode, the inhibition effect of melanoids on anaerobic microorganisms is eliminated, and meanwhile efficient dissolution of organic matter in sludge is promoted. Nano-manganese dioxide generated by oxidizing potassium permanganate serves as an electron transfer medium, the metabolic activity of acid-producing bacteria is further enhanced, and the acid pickling recovery rate is larger than or equal to 90%. According to the method, the yield of short-chain fatty acid is increased by 65% (as high as 456mg / g VS), high efficiency and environmental friendliness are achieved, and an innovative solution is provided for sludge resourceful treatment.

This invention relates to the field of microbial technology, and particularly to a compound lactic acid bacteria fermentation agent and its application, a method for producing *Anoectochilus roxburghii* fermentation broth, and related products. The compound lactic acid bacteria fermentation agent comprises *Lactobacillus plantarum* BXM2, *Lactobacillus fermentatus* J IAN, and *Lactobacillus paracasei* YYS-69. Fermenting *Anoectochilus roxburghii* broth using this compound fermentation agent results in stronger acid production, higher viable bacterial counts, and significantly improved antioxidant activity, total polyphenol and flavonoid content, and enhanced hypoglycemic activity. Sensory effects are also significantly improved. This compound lactic acid bacteria fermentation agent, when applied to the fermentation of traditional Chinese medicine, can enhance the antioxidant capacity and effective functional component content of the fermentation broth, thereby improving efficacy. It has great application prospects in the field of deep-processed *Anoectochilus roxburghii* products and even other fermented medicinal and edible products.

The invention discloses an automatic control method and system for fumaric acid production. The method comprises the following steps: collecting process variables in a fermentation process; constructing a soft measurement model fusing physical modeling and a residual neural network to obtain an acid production rate prediction value and prediction confidence; calculating a feed-forward control quantity, and adjusting the weight according to the prediction confidence to obtain a feed-forward control output; constructing a state vector, and establishing a Markov decision process; training a neural network control strategy by adopting a near-end strategy optimization algorithm, and outputting a proportionality coefficient, an integral coefficient and a differential coefficient; calculating feedback control quantity, fusing the feedback control quantity with feed-forward control output, and applying change rate and amplitude limitation to obtain final control output; and switching to a feedback priority control mode under a specific condition, and regularly updating a soft measurement model and a control strategy parameter. According to the invention, high-precision stable control of pH in the fumaric acid fermentation process is realized, the production efficiency and the process robustness are improved, and the method is suitable for automatic control of the large-scale fermentation process.

The invention relates to a method for preparing fish feed by secondary utilization of traditional Chinese medicine wastes, and belongs to the technical field of fish feed. After the traditional Chinese medicine waste is pretreated to remove heavy metal, primary fermentation of bacillus subtilis and aspergillus niger is carried out, the bacillus subtilis can degrade cellulose, the aspergillus niger decomposes antinutritional factors, then fermentation of lactobacillus lactis and candida utilis is carried out, lactic acid bacteria produce acid to inhibit infectious microbes, flavor substances are synthesized, and palatability is improved. Through traditional Chinese medicine residue pretreatment, multi-strain synergistic fermentation and a scientific feed formula, efficient reutilization of traditional Chinese medicine waste is successfully realized, and the fish feed which is rich in nutrition, high in safety and remarkable in economic benefit is produced.

The present invention discloses the use of pantothenic acid in the preparation of anticaries preparations related to Streptococcus mutans, and anticaries preparations containing pantothenic acid. The invention belongs to the field of biomedicine technology. The anticaries preparations related to Streptococcus mutans include an acid production inhibitor for Streptococcus mutans, a growth inhibitor for Streptococcus mutans, an inhibitor of cariogenic toxins of Streptococcus mutans, and an inhibitor of interspecies competition of Streptococcus mutans. Pantothenic acid can be used to influence the acid production, growth, production of cariogenic toxins, and interspecies competition of Streptococcus mutans, thereby maintaining the balance of the oral microecology.

The invention discloses antibacterial mouthwash as well as a preparation method and application thereof, and belongs to the technical field of daily chemical products. According to the invention, egg white lysozyme, ferulic acid and grape seed procyanidine are taken as core components, and the mouthwash with an efficient bacteriostatic effect is developed. And the antibacterial rates of streptococcus mutans and porphyromonas gingivalis are 96.88% and 96.30% respectively. Researches show that bacterial biofilms can be destroyed by using the mouthwash, and the biofilm quantity is reduced by 53.7% after the bacterial biofilms are treated for 24 hours; extracellular polysaccharide is inhibited, the content of water-insoluble glucan is reduced by 62.3%, and synthesis of a key cariogenic matrix is hindered; the acid production capacity is regulated and controlled, the pH change of 24-hour culture is only 1.50, and xylitol competitively inhibits glycolysis and cooperates with ferulic acid to block bacterial metabolism. The mouthwash prepared by the invention avoids the problem of enzyme activity inhibition of the ionic surfactant of the traditional mouthwash, takes effect more quickly, and provides a basis for developing natural, safe and efficient functional mouthwash.

The invention belongs to the technical field of acid-making tail gas treatment, and relates to an efficient purification device for acid-making tail gas. The device comprises a tower body, a first connecting plate, a second connecting plate and a rubber elastic pipe, the two ends of the first connecting plate and the two ends of the second connecting plate are connected with rubber elastic pipes. An elastic film is arranged on the inner wall of the air spraying head, and a triggering piece is arranged on the tower body. The lower end of the rubber elastic tube on the first connecting plate is connected with a magnet ball, and the lower end of the rubber elastic tube on the second connecting plate is connected with an iron ball. The rubber elastic pipe is stretched, so that the elastic film bulges in the direction close to the axis of the jet head, the flow area of the jet head is reduced, the jet distance of the jet head is prolonged, acid-making tail gas and alkaline liquid are mixed more uniformly, the reaction efficiency is improved, and the purification efficiency is further improved. And the distance between the adjacent gas spraying heads is increased, so that the gas spraying heads are distributed more dispersedly, and the acid-making tail gas is sprayed into the alkaline liquid more uniformly.

The utility model relates to the technical field of OB acid production, in particular to a convenient-to-discharge hydrolysis kettle for OB acid production and processing, which comprises a vertical reaction kettle body, a bottom discharge valve is mounted at the bottom of the vertical reaction kettle body, and a plurality of side discharge ports which are sequentially staggered from top to bottom are formed in the side wall of the vertical reaction kettle body. A plurality of side discharge ports are formed in the vertical reaction kettle body, a rotary sleeve which is hermetically and circumferentially surrounded on the vertical reaction kettle body is arranged outside the plurality of side discharge ports, a plurality of side discharge pipes which can be communicated with the plurality of side discharge ports one by one are fixedly communicated with the outer part of the rotary sleeve, and side discharge valves are fixedly mounted on the plurality of side discharge pipes. And the discharging accuracy is high, the discharging speed is high, and the production efficiency of the OB acid is further improved.

The invention relates to the technical field of hydrocyanic acid production, in particular to a high-yield hydrocyanic acid chemical process which comprises the following steps: 1) respectively pretreating ammonia gas, natural gas and air, mixing according to a ratio, and inputting into a hydrocyanic acid reactor; (2) carrying out oxidation reaction on the raw material gas under a certain condition under the catalytic action of a platinum alloy net to prepare ammonia-containing hydrocyanic acid gas; 3) performing ammonia removal treatment on the hydrocyanic acid gas to obtain purified hydrocyanic acid gas and an ammonium sulfate solution containing cyanide; 4) carrying out cyanogen removal treatment on the ammonium sulfate solution to obtain mixed gas containing hydrocyanic acid and a cyanogen-free ammonium sulfate solution; according to the method, the area of a platinum alloy net capable of being contained is increased, the reaction area playing a catalytic role is increased, then the reaction efficiency is improved, and the single-line productivity is improved.

The invention discloses an ethanol-tolerant and acetic-tolerant acetobacter pasteurianus strain and application thereof in production of fruit vinegar. The invention provides an acetobacter pasteurianus CL247, the classification name of the acetobacter pasteurianus is Acetobacter pasteurianus, the acetobacter pasteurianus is preserved in China General Microbiological Culture Collection Center (CGMCC) on March 21, 2025, the preservation number is CGMCC No.33924, and the preservation address is Institute of Microbiology, Chinese Academy of Sciences, No. 3, Beichen West Road, Chaoyang District, Beijing. The acetobacter pasteurianus CL247 has the characteristics that the acid yield in 72 hours is greater than or equal to 49 g / L, and the acetobacter pasteurianus CL247 can tolerate 7% acetic acid and 18% ethanol. An efficient, tolerant and stable strain solution is provided for fruit vinegar production, the industry is promoted to be upgraded from'low-efficiency discontinuous' to'efficient continuous', and remarkable technical innovation and economic value are achieved.

The application discloses a preparation method of yellow rice wine, the yellow rice wine and application. The preparation method of the yellow rice wine comprises the following steps: gelatinizing starch raw materials to prepare gelatinized starch; uniformly mixing the gelatinized starch, yellow rice wine starter, acidic protease, saccharomyces cerevisiae, yellow rice wine and water to prepare fermentation material, and performing fermentation; adding lactic acid bacteria at 72h-74h of fermentation, and continuing fermentation; and performing solid-liquid separation after the fermentation is completed, collecting clear liquid, decocting wine, aging, and preparing the yellow rice wine. The preparation method of the yellow rice wine breaks through the technical bottleneck that the metabolic time sequence of strains is uncontrollable in traditional mixed fermentation, optimizes the inoculation time of lactic acid bacteria, guarantees the acid production capacity of lactic acid bacteria under the condition of controlling alcohol metabolism, and obtains the yellow rice wine with the characteristics of high sugar, high acid and high ester, which can be used for seasoning.

The utility model relates to a pyrite acid-making drying tower, and belongs to the field of drying towers, the pyrite acid-making drying tower comprises a tower body, a plurality of inclined plates are arranged in the tower body, the sides, away from the inner wall of the tower body, of the inclined plates incline downwards, a plurality of acid inlet pipes are arranged in the tower body, and a plurality of acid spraying pipes are connected to the acid inlet pipes. The multiple inclined plates divide the tower body into the multiple cavities, the staying time of sulfur-containing furnace gas in the tower is prolonged, and the multiple acid inlet pipes and the multiple acid spraying pipes are arranged, so that the spraying uniformity degree is improved.

The invention belongs to the technical field of biomass energy utilization, and particularly relates to a biogas fermentation system and method. The biogas fermentation system comprises a pretreatment section, a desulfurization section, a hydrolysis section, an acid production section and a methane production section which are sequentially arranged from top to bottom. A discharge pipe at the bottom of the pretreatment section penetrates through the liquid distributor to reach the middle part of the desulfurization section; the return pipe is connected with the liquid distributor through the pump; gas in the hydrolysis section enters the desulfurization section for desulfurization through a gas guide pipe and a floating valve group in the desulfurization section; gas in the acid production section enters the hydrolysis section through a gas guide pipe and a floating valve group in the hydrolysis section to be hydrolyzed; and gas in the methane production section enters the acid production section through a gas guide pipe and a floating valve group in the acid production section to be subjected to acid production treatment. According to the invention, CO2 removal, H2S removal, oxygen removal, ammonia removal, mercaptan removal, halogenated hydrocarbon removal and siloxane removal are carried out on the fermentation system through a plurality of strengthening means, so that high-quality biogas and functionalized biogas slurry are obtained.

The present application belongs to the technical field of microorganisms, and particularly relates to a bacillus licheniformis BL-C15 and application thereof. The present application provides a bacillus licheniformis BL-C15, which is characterized in that the bacillus licheniformis BL-C15 is preserved in the China General Microbiological Culture Collection Center on November 25, 2024, has a preservation number of CGMCC No. 32787, and has a preservation address of No. 3, Xili, Beichen, Beijing, China. The strain has the characteristics of high-alkali tolerance, salt tolerance and acid production, can effectively repair saline-alkali degraded soil, has a significant plant growth-promoting effect, and has important application value in the field of saline-alkali soil repair. The strain can also be used for preparing a microbial product for repairing saline-alkali soil.

This invention relates to the field of oral care products technology, specifically to an artificial enzyme with antibacterial properties, its preparation method, and its application. This technical solution employs a chemical reduction method, where a palladium source reacts in an environment containing surfactants and reducing agents to obtain palladium nanozymes. The obtained palladium nanozymes exhibit uniform morphology, controllable particle size, good dispersibility in water, and good biocompatibility; they have no significant toxic side effects on human gingival fibroblasts, possess highly efficient catalase activity, and demonstrate strong antibacterial and bactericidal effects against oral pathogens, significantly reducing bacterial drug resistance; they can inhibit acid production by oral bacteria, preventing tooth decay; and they retain their original catalytic activity even after multiple cycles of use. Applying the palladium nanozymes of this solution to the manufacture of oral care products can solve the technical problems of unsatisfactory safety and easy development of drug resistance in existing oral care products using antibacterial and anti-caries methods, showing promising application prospects.

The present application relates to a kind of dry method for viscose fiber factory waste gas recovery, including the following sequentially performed steps: (1) waste gas incineration;(2) purification;(3) deacidification mist;(4) drying;(5) sulfur combustion;(6) high temperature furnace gas B is imported into the acid making device to obtain finished product concentrated sulfuric acid.The present application overcomes the shortcomings of existing viscose factory waste gas acid making process equipment, such as easy to be corroded, frequent shutdown, difficult to maintain, low acid production, easy to escape sulfur waste gas, easy to mix furnace gas and external air, low economic benefit, complex process, and many by-products, etc.By adding liquid sulfur mixed combustion, controlling the temperature of each step, setting a booster fan in the front section of the drying tower, a main fan in the rear section, and reasonably arranging the inlet positions of furnace gas and external air, the present application has the advantages of simple process, large-scale acid production, no sulfur waste gas escaping, more environmentally friendly, no mixing of furnace gas and external air, high economic benefit, few by-products, and low maintenance cost.

The utility model discloses a reactor oxidant adding conversion connecting device for manufacturing 2-chloronicotinic acid, which comprises a transition main tank body, feeding through holes are formed in the left part, the right part, the front part and the rear part of a top plate of the transition main tank body, and feeding connecting pipes are fixed on the top surface of the top plate of the transition main tank body corresponding to the feeding through holes; the feeding connecting pipes are aligned and communicated with the corresponding feeding through holes, a horizontal partition plate is fixed to the inner side wall of the upper portion of the transition main tank body, and through holes are formed in the positions, opposite to the feeding through holes, of the horizontal partition plate; a motor fixing frame is fixed to the middle of the top face of a top plate of the transition main tank body, and a rotary servo motor is fixed to the top face of a top plate of the motor fixing frame. The device can be installed on an oxidizing agent feeding port of a reactor, different oxidizing agents can be switched for adding and using according to needs, repeated disassembly is not needed, and the device is very convenient and good in using effect.

The invention belongs to the technical field of solid waste treatment, and particularly discloses a preparation method for increasing the content of soluble calcium in fish bones. The method comprises the following steps: pretreating fish bones to obtain fish bone powder; mixing fish bone meal and water, and sterilizing to obtain a fermentation substrate; according to the method, bacillus subtilis, lactobacillus plantarum and saccharomycetes are adopted for multi-strain sequential fermentation, the bacillus subtilis is inoculated firstly for ventilation fermentation for 2-4 days, the pH is adjusted to 6.5-7.0, then sterilization is performed, a carbon source is added, a mixed bacterium solution of the lactobacillus plantarum and the saccharomycetes is inoculated, and ventilation fermentation is performed for 2-4 days. Through a specific strain combination and an innovative sequential fermentation process, the enzyme production capacity of bacillus subtilis and the acid production capacity of lactobacillus plantarum and saccharomycetes are remarkably improved, dissolution of calcium in fish bones is synergistically promoted, the problem of bitter taste generated by a traditional enzymolysis method is avoided, and the method has the advantages of high efficiency, greenness and complete nutrition retention.

A tryptophan fermentation device comprises a tank body, and a first baffle plate, a second baffle plate, several groups of stirring paddles, a high-pressure liquid sugar tank, a material supplementing tank and a sterile air device which are positioned in the tank body, the baffle plates in the fermentation tank are designed to be hollow and are provided with holes, and the sterile air device is connected with the first baffle plate in the tank body through a pipeline; the air is distributed more uniformly when entering, and the dissolved oxygen is improved; the high-pressure liquid sugar tank and the supplementing tank are connected with a second baffle in the tank body through a pipeline, so that sugar and supplemented materials are distributed more uniformly when entering the fermentation tank, byproducts generated due to excessive local sugar concentration are reduced, and acid production and conversion rate of tryptophan are facilitated.