Solid fungicide, preparation method and application

Abstract

The invention relates to the technical field of kitchen waste treatment, in particular to a solid fungicide, a preparation method and application. The solid microbial inoculum comprises a microbial inoculum and a carrier; the microbial agent is prepared from pseudoochrobactrum saccharum, alcaligenes faecalis, achromobacter xylosoxidans, paenibacillus amyloliquefaciens, bacillus cereus, sphingobium nicotianae, serratia marcescens, stenotrophomonas maltophilia, sphingobium humus, sphingobium aquaticum and bacillus subtilis; the carrier for carrying the liquid compound bacteria is bagasse, and the maximum number of released bacteria is 2.2 * 10 < 9 > CFU / g. When the solid microbial inoculum is added into a 18 L kitchen waste reactor, the waste decrement rate is 80% within 7 days, and the COD removal rate can reach 79.1% at most. According to the solid microbial agent disclosed by the invention, organic substances in the kitchen waste can be degraded while the kitchen waste is converted from a solid state to a liquid state, so that volume reduction and weight reduction of the kitchen waste are realized; and the solid microbial inoculum is convenient to transport and operate and low in cost, has positive significance on difficulties faced by kitchen waste treatment, and has a good application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of kitchen waste treatment, and particularly relates to a solid bacterium agent, a preparation method and an application thereof. Background Art

[0002] According to the urban waste statistical data released by the Ministry of Housing and Urban-Rural Development, the annual production of kitchen waste in China accounts for more than 60% of the total domestic waste, and in some areas, it even reaches 70% - 80%. Kitchen waste is characterized by high water content (60% - 80%), high organic matter content (95% - 98%), high salt content, etc. It is easily decomposed by microorganisms and undergoes putrefaction and deterioration, generating a large amount of garbage leachate and malodorous gases, which has an adverse impact on environmental sanitation.

[0003] The aerobic biological treatment technology is a process in which composite microorganisms with strong degradation ability decompose kitchen waste under aerobic conditions. The advantages of this treatment technology are short time, high degree of automation, and the ability to achieve the treatment goals of reduction, harmlessness, and resource utilization of kitchen waste. Although incineration, landfill, mechanical crushing, feed treatment, and composting treatment technologies all have the advantage of simple treatment processes, incineration, landfill, and mechanical crushing respectively cause secondary pollution to the atmosphere, soil, water bodies, etc. and have a very low degree of resource utilization. The feed treatment technology has a certain impact on human health. The anaerobic digestion technology is relatively mature, but it has a high input cost and limited equipment treatment capacity.

[0004] A composite microorganism bacterium agent is a kind of microorganism bacterium agent that co-cultures two or more microorganisms in an appropriate proportion to give full play to the combined effect of the group and achieve the best application effect. At present, the main organic material composting bacterium agents at home and abroad include nitrogen-fixing bacteria, phosphorus-solubilizing bacteria, cellulose-decomposing bacteria, composite microorganism bacterium agents, etc. Among them, the composite microorganism bacterium agent has become an important development direction at home and abroad in recent years due to its strong environmental adaptability and relatively stable effect. Although the production of composite microorganism bacterium agents by liquid fermentation technology has the advantages of short culture period, high production efficiency, high microbial activity, high degree of automation and mechanization, etc., strict aseptic conditions need to be strictly controlled during the preparation process, and the requirements for storage conditions are relatively high. Special preservation methods need to be adopted. As the preservation time of the bacterial strain prolongs, the bacterial strain is easily contaminated and degenerated, and it needs to be activated and enlarged cultured before fermentation. Therefore, there are disadvantages such as short preservation time, inconvenient storage and transportation. Summary of the Invention

[0005] In view of this, in order to overcome the problems that existing liquid bacterial agents are prone to contamination during the preservation period, have a short preservation time, and are inconvenient to carry and transport, the present invention provides a solid bacterial agent, a preparation method and an application. This method finally prepares a solid bacterial agent by optimizing the composite bacterial carrier material. After vacuum freeze-drying, it can maintain the original properties of microorganisms for a long time, extend the shelf life of the bacterial agent, and can quickly liquefy food waste after being used to treat food waste, convert food waste from solid state to liquid state, decompose macromolecules into small molecules, improve the utilization rate of nutrients in sewage by microorganisms, facilitate subsequent purification and resource utilization, and at the same time achieve volume reduction and weight reduction of food waste.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The first technical object of the present invention is to provide a preparation method of a solid bacterial agent, comprising the following steps:

[0008] (1) Inoculate 11 kinds of bacteria from the slant solid medium into the PDB liquid medium respectively, and culture them in a shaker at 130-150 rpm for 24-48 h to obtain liquid bacteria.

[0009] (2) Mix 11 kinds of liquid bacteria with a biomass of 0.3-0.8 g / L respectively and add them to bagasse, soybean meal, corn straw powder, corn cob powder or peanut shell powder to obtain a solid bacterial agent.

[0010] (3) Place the solid bacterial agent in a freeze dryer, with a freezing time of 0.5-2 h, a cold trap temperature of -80 to -95 °C, a vacuum time of 24-48 h, and a vacuum pressure of 1-8 Pa to obtain the solid bacterial agent.

[0011] Preferably, the 11 kinds of bacteria are respectively Pseudochrobactrum asaccharolyticum, Alcaligenes faecalis, Achromobacter xylosoxidans, Paenibacillus amylolyticus, Bacillus cereus, Sphingobacterium tabacinasale, Serratia marcescens, Stenotrophomonas maltophilia, Sphingobacterium humi, Sphingobacterium watsonii, Bacillus subtilis, and their biomass ratio is 1:1:1:1:1:1:1:1:1:1:1.

[0012] It should be noted that the above 11 kinds of bacteria are all preserved in the China General Microbiological Culture Collection Center CGMCC. For specific preservation instructions, please refer to Chinese Patent CN117965383A, a dominant bacterial combination for liquefying and degrading food waste and its application.

[0013] Preferably, the solid carrier with the most bacteria release is bagasse, and the solid carrier with the best overall degradation effect on starch, protein, oil and cellulose media is bagasse.

[0014] The second technical object of the present invention is to provide a solid bacterial agent prepared by the above method

[0015] The third technical object of the present invention is to provide the application of the solid bacterial agent prepared by the above method in treating kitchen waste

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows

[0017] 1) The present invention provides a preparation method of a solid bacterial agent. The solid bacterial agent includes a bacterial agent and a carrier, and can specifically decompose starch, protein, oil, and cellulose components in kitchen waste. The bagasse has a loose texture, good pore structure, large specific surface area, and provides a large number of attachment sites for bacteria

[0018] 2) The solid bacterial agent of the present invention can convert kitchen waste from solid state to liquid state while degrading organic substances in kitchen waste, realizing volume reduction and weight reduction of kitchen waste; and the solid bacterial agent is convenient for transportation, easy to operate, and low in cost, which has positive significance for the difficulties faced in kitchen waste treatment and has good application prospects Description of the Drawings

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts

[0020] Figure 1 It is the water absorption rate diagram of different carriers in Example 1 and Comparative Examples 1-4

[0021] Figure 2 It is the bacterial release number diagram of different solid bacterial agents in Example 1 and Comparative Examples 1-4

[0022] Figure 3 It is the degradation effect diagram of different solid bacterial agents on starch, protein, oil, and cellulose in Example 1 and Comparative Examples 1-4

[0023] Figure 4 It is the dry weight change diagram of kitchen waste in 6 days in Example 2 and Comparative Examples 5-6

[0024] Figure 5 It is the COD change diagram of the liquefied liquid of kitchen waste in 6 days in Example 2 and Comparative Examples 5-6

[0025] Figure 6 It is a photo of the 18L kitchen waste reactor in Example 3

[0026] Figure 7The figure shows the removal rate of COD in the effluent of the liquefied liquid of food waste after the solid bactericide in Example 3 was degraded for one night (14h) (the abscissa 1-7 in the figure are the comparison times of the COD removal rate respectively). Detailed implementation mode

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0028] The special term "embodiment" used here does not necessarily mean that any embodiment described as "exemplary" is better than or superior to other embodiments. Unless otherwise specified, the performance index tests in the embodiments of this application adopt the conventional test methods in the art. It should be understood that the terms described in this application are only used to describe specific embodiments, and are not used to limit the content disclosed in this application.

[0029] Unless otherwise specified, the technical and scientific terms used in this article have the same meanings as those generally understood by those of ordinary skill in the technical field to which this application belongs; the test methods and technical means not specifically noted in other parts of this application refer to the experimental methods and technical means commonly adopted by those of ordinary skill in the art.

[0030] To better illustrate the content of this application, numerous specific details are given in the following specific embodiments. Those skilled in the art should understand that this application can also be implemented without some specific details. In the embodiments, some methods, means, instruments, equipment, etc. well-known to those skilled in the art are not described in detail, so as to highlight the main idea of this application.

[0031] On the premise of no conflict, the technical features disclosed in the embodiments of this application can be combined arbitrarily, and the obtained technical solutions belong to the content disclosed in the embodiments of this application.

[0032] The present invention discloses a preparation method of a solid bactericide. The solid bactericide includes a bactericide and a carrier. The bactericide includes Pseudochrobactrum asaccharolyticum, Alcaligenes faecalis, Achromobacter xylosoxidans, Paenibacillus amylolyticus, Bacillus cereus, Sphingobacterium tabacis, Serratia marcescens, Stenotrophomonas maltophilia, Sphingobacterium humi, Sphingobacterium watsonii, Bacillus subtilis, and the carrier for carrying the liquid composite bacteria is bagasse.

[0033] It should be noted that the bagasse provided by the present invention has low cost, wide sources, good water absorption effect, loose texture, and can accommodate more bacterial liquid. The freeze-drying method can fix the composite bacteria in the bagasse at low temperature. Therefore, the preparation method described in the present invention can improve the preservation time of the bacterial agent and realize the recycling of waste.

[0034] In the present invention, the preparation method of the solid bacterial agent includes the following steps:

[0035] (1) Inoculate 11 kinds of bacteria from the slant solid medium into the PDB liquid medium respectively, and culture them in a shaker at 150 rpm for 48 h.

[0036] (2) Mix 11 kinds of liquid bacteria with a biomass of 0.5 g / L respectively and add them to the bagasse.

[0037] (3) Place the solid bacterial agent in a freeze dryer, with a freezing time of 2 h, a cold trap temperature of -88.9 °C, a vacuum time of 48 h, and a vacuum pressure of 2 Pa.

[0038] In the present invention, the biomass of the 11 kinds of liquid bacteria is preferably 0.3 - 0.8 g / L, more preferably 0.5 g / L; the culture medium of the 11 kinds of bacteria in the present invention is preferably the PDB medium, the rotation speed in the shaker is 130 - 150 rpm, more preferably 150 rpm; the oscillation culture time is 24 - 48 h, and the biomass increases, more preferably 48 h; the freezing time in the freeze dryer is 0.5 - 2 h, more preferably 2 h; the vacuum time is 24 - 48 h, more preferably 48 h.

[0039] The present invention also provides the application of the preparation method described in the above technical solution in treating liquefied food waste. Using the preparation method provided by the present invention can effectively degrade the organic matter in food waste.

[0040] To better understand the present invention, the following examples are used to further specifically illustrate the present invention, but it should not be understood as a limitation of the present invention. For some non-essential improvements and adjustments made by those skilled in the art according to the above invention content, they are also considered to fall within the protection scope of the present invention.

[0041] It should be noted that the 11 strains used in the following experiments are respectively Pseudochrobactrum asaccharolyticum (preservation number: CGMCC No. 27442), Alcaligenes faecalis (preservation number: CGMCC No. 27443), Achromobacter xylosoxidans (preservation number: CGMCC No. 27444), Paenibacillus amylolyticus (preservation number: CGMCC No. 27445), Bacillus cereus (preservation number: CGMCC No. 27446), Sphingobacterium tabacisoli (preservation number: CGMCC No. 27447), Serratia marcescens (preservation number: CGMCC No. 27448), Stenotrophomonas maltophilia (preservation number: CGMCC No. 27449), Sphingobacterium humi (preservation number: CGMCC No. 27450), Sphingobacterium aquimaris (preservation number: CGMCC No. 27451), and Bacillus subtilis (preservation number: CGMCC No. 27452).

[0042] Example 1

[0043] The 11 strains were respectively inoculated from the plate into PDB medium and cultured in a shaker at 150 rpm and 35 °C for 48 h. Subsequently, the 11 liquid strains were mixed in equal volume and slowly added to the solid carrier bagasse according to a certain volume gradient (5 mL each time) and thoroughly mixed. When the carrier no longer absorbed water, the addition of the bacterial liquid was stopped, and the water absorption rate of each portion of the carrier was calculated. The water absorption rate = (mass of the carrier after full water absorption (g) - mass of the carrier (g)) / mass of the carrier (g) × 100%.

[0044] The 11 liquid strains were mixed with a biomass of 0.5 g / L and added to bagasse, followed by freeze-drying. The freezing time was 2 h, the cold trap temperature was -88.9 °C, the vacuum time was 48 h, and the vacuum pressure was 2 Pa. 1 g of the freeze-dried solid bacterial powder was taken out and placed in a centrifuge tube, and 50 ml of sterile water was added, and then shaken for 30 min to obtain a bacterial suspension. 100 μL of the bacterial suspension was taken and inoculated onto PDB medium by the plate coating method. After culturing for 48 h, the number of bacteria released from the solid bacterial agent bagasse was measured. 1 ml of the bacterial suspension after shaking the composite bacterial powder was taken out and subjected to 10 3 、10 4 、10 5 、10 6 、10 7 、10 8 gradient dilutions. The obtained bacterial liquid was respectively spotted onto the degradation screening media for starch, protein, oil, and cellulose by the spot inoculation method. After culturing for 48 h, the transparent circle diameter (D) and colony diameter (d) of each plate were measured with a caliper. The ratio (D / d) can be used to characterize the treatment ability of the strain for various substances in food waste. Each experimental group contained 3 parallel samples.

[0045] Example 2

[0046] Add 5 g of the prepared solid bacterial agent to 250 ml of kitchen waste liquefied liquid (culture medium) and culture for 48 h to obtain a bacterial liquid. Dilute the bacterial liquid 1-fold with distilled water to obtain a diluted bacterial liquid. Place 30 g of kitchen waste and 50 g of the diluted bacterial liquid in a 100 mL conical flask and mix well to obtain a kitchen waste mixture. Place the conical flask in a constant temperature water bath oscillator at a temperature of 30 °C and a rotation speed of 130 r / min, and react for 6 days. Take water samples every day to measure their COD concentration, and measure the dry weight of the kitchen waste. The dry weight is measured by the direct drying method. Separate the solid and liquid of the waste, take a washed weighing dish to hold the solid waste, place it in a drying oven at 105 °C, heat for 2 h, then put it in a desiccator and cool to room temperature before weighing. Each experimental group contains 3 parallel samples.

[0047] Example 3

[0048] The present invention aims to solve the problem of the degradation and reduction of kitchen waste, and provides a small-scale test process and method for degrading kitchen waste using a solid bacterial agent, successfully achieving significant degradation and reduction of kitchen waste.

[0049] An 18 L kitchen waste reactor operates for 24 h, with a cycle of 7 days. The operating parameters include a stirring operation time of 2 min, an interval time of 43 min, a spraying operation time of 40 s, an interval time of 30 min, a dosing operation time of 20 s, an interval time of 3 h, and a temperature of 25 - 30 °C. Within 7 days, the 18 L kitchen waste reactor processed 21 catties of kitchen waste. After degradation by the composite bacteria, the waste reduction rate reached 80%.

[0050] The calculation formula for the kitchen waste reduction rate is as follows: Kitchen waste reduction rate = 1 - (4.2 / 21) = 80% (Note: The parameter 4.2 is the mass of the remaining undegraded waste in the kitchen waste reactor after 7 days).

[0051] To further prove the beneficial effects of the present invention and better understand the present invention, the following comparative examples are used to further clarify the technical features disclosed by the present invention, but it should not be construed as a limitation to the present invention. For other improvements made by those skilled in the art based on the above-mentioned invention content without creative work, they are also considered to fall within the protection scope of the present invention.

[0052] Comparative Example 1

[0053] The solid carrier is soybean meal, and other steps are the same as those in Example 1.

[0054] Comparative Example 2

[0055] The solid carrier is corn straw powder, and other steps are the same as those in Example 1.

[0056] Comparative Example 3

[0057] The solid carrier is corncob powder, and the other steps are the same as those in Example 1.

[0058] Comparative Example 4

[0059] The solid carrier is peanut shell powder, and the other steps are the same as those in Example 1.

[0060] Comparative Example 5

[0061] The culture solution is distilled water, and the other steps are the same as those in Example 2.

[0062] Comparative Example 6

[0063] The culture solution is PDB, and the other steps are the same as those in Example 2.

[0064] The results are as Figure 1 shown. In Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4, the highest water absorption rate in Example 1 is 492.9%. It can be seen from Figure 2 that the number of bacteria released per gram in Example 1 is the largest, which is 2.2×10 9 CFU / g. It can be seen from Figure 3 that in the protein, oil, and cellulose culture media, the ratio of the hydrolysis zone to the colony diameter in Example 1 is the highest, which are 2.13, 1.47, and 1.6 respectively. In the starch culture media, the D / d ratio in Example 1 is also relatively high, which is 2.3. Generally speaking, Example 1 has the best effect as the solid carrier of the liquid bacterial agent.

[0065] As Figure 4 shown, after using the kitchen waste liquefied liquid as the culture solution for activating the solid bacterial agent in Example 2, the degradation and liquefaction effects of the kitchen waste are the best. The dry weight of the kitchen waste only remains 1.25 g on the 6th day. It can be obtained from Figure 5 that at the end of the experiment on the 6th day, the COD of the kitchen waste mixed liquid in Example 2 can be reduced from 41833 mg / L on the first day to 20966 mg / L, and the degradation rate reaches 50%, with the best effect. The removal of COD in Comparative Example 5 is unstable.

[0066] The solid bacterial agent of the present invention is applied to an 18 L kitchen waste reactor for one week. The specific operation steps are as follows:

[0067] (1) Activate and culture the solid bacterial agent with the kitchen waste liquefied liquid in the laboratory to obtain a bacterial liquid;

[0068] (2) Add the composite bacterial liquid into the 18 L kitchen waste reactor, and at the same time add the bacterial attachment material, fruit tree sawdust;

[0069] (3) Measure the amount of garbage fed each time, collect the effluent before and after the garbage feeding, and detect the effluent quality.

[0070] The results are asFigure 7 As shown, after being degraded by the solid microbial agent for one night (14 h), the highest removal rate of COD in the effluent of the liquefied kitchen waste liquid can reach 79.1% (the abscissas 1-7 in the figure are the comparison times of the COD removal rate respectively).

[0071] In summary, the solid microbial agent can effectively degrade liquefied kitchen waste.

[0072] As can be seen from the above examples, the present invention provides a preparation method and application of a solid microbial agent. The solid microbial agent includes a microbial agent and a carrier. The microbial agent includes Pseudochrobactrum asaccharolyticum, Alcaligenes faecalis, Achromobacter xylosoxidans, Paenibacillus amylolyticus, Bacillus cereus, Sphingobacterium tabacinasense, Serratia marcescens, Stenotrophomonas maltophilia, Sphingobacterium humi, Sphingobacterium aquimaris, Bacillus subtilis, and the carrier is bagasse. Using the solid microbial agent of the present invention to treat kitchen waste, in the small-scale application of an 18 L kitchen waste reactor, the solid microbial agent can still achieve good continuous degradation effect on kitchen waste. The waste reduction rate within one week is 80%, and the highest COD removal rate can reach 79.1%. The culture conditions of this composite bacterium are easy to achieve and control, and can effectively degrade and liquefy kitchen waste, which is of great significance for the efficient treatment of kitchen waste.

[0073] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a solid bacterial agent, characterized in that: The following steps are involved: (1) Inoculate the bacterial agent from the slant solid culture medium into the PDB liquid culture medium to obtain a liquid bacterial agent; (2) mixing the liquid bacterial agent and adding it to a solid carrier to obtain a solid bacterial agent; (3) The solid bacterial agent is vacuum freeze-dried to obtain the solid bacterial agent.

2. The method for preparing the solid bacterial agent according to claim 1, characterized in that: The bacterial agents include Pseudochrobacterium insaccharolyticum, Bacillus faecalis, Colorless Bacillus xylosoxidans, Bacillus amyloliquefaciens, Bacillus cereus, Sphingobacterium spp. in tobacco fields, Serratia marcescens, Stenotrophomonas maltophilia, Sphingobacterium spp. in humus soil, Sphingobacterium waterii, and Bacillus subtilis, and the biomass ratio of each bacterial agent is 1:1:1:1:1:1:1:1:1:1:1:1:1:

1.

3. The method for preparing the solid bacterial agent according to claim 1 or 2, characterized in that: The culture conditions in step (1) are: shaking culture at 130 to 150 rpm in a shaker for 24 to 48 hours.

4. The method for preparing the solid bacterial agent according to claim 1 or 2, characterized in that: The biomass of each bacterium in the liquid bacterial agent is 0.3-0.8 g / L, and the solid carrier includes bagasse, soybean meal, corn stalk powder, corn cob powder, and peanut shell powder.

5. The method for preparing the solid bacterial agent according to claim 1 or 2, characterized in that: The freeze-drying conditions in step (3) are: freezing time of 0.5 to 2 h, cold sink temperature of -80 to -95°C, vacuum time of 24 to 48 h, and vacuum pressure of 1 to 8 Pa.

6. A solid bacterial agent prepared by the method as claimed in claim 1.

7. Use of the solid bacterial agent prepared by the method as claimed in claim 1 in treating food waste.

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