Efficient aerobic fermentation corncob-based biological conditioner and application thereof

Abstract

The invention discloses a high-efficiency aerobic fermentation corncob-based biological conditioner and application thereof. Aiming at the common problems of unstable carrier effect, poor environmental adaptability, easiness in inactivation of the microbial inoculum, difficulty in continuously exerting efficacy and the like existing in the existing composting microbial inoculum, the agricultural waste corncob with a porous structure and excellent water-retaining and fertilizer-retaining natural characteristics is pretreated and modified; and the immobilized carrier of the aerobic fermentation inoculant with high activity and high stability is constructed. The carrier matrix can be used for efficiently loading and remarkably improving the expanding culture core aerobic fermentation functional flora to prepare a solid biological conditioner. The corncob-based biological conditioner is applied to the composting process of organic solid wastes, promotes the humification process of organic materials, shortens the composting period, improves the fermentation efficiency of the materials, and effectively improves the resource utilization level of the organic solid wastes.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microbial fermentation, in particular to a high-efficiency aerobic fermentation corncob-based biological conditioner and application thereof. BACKGROUND

[0002] Aerobic composting of agricultural and pastoral wastes is the most widely used effective means of harmless and resource utilization. However, the traditional composting technology cannot meet the current demand, and the use of microorganisms to promote the resource utilization of agricultural and pastoral wastes has become a hot research topic.

[0003] Microbial agents can improve the fermentation quality of composting during the composting process. In particular, a composite microbial agent formed by the combination of multiple functional microorganisms can improve microbial diversity during the composting process, has better processing capacity for tolerance and toxicity response in combination with various enzyme activities, accelerates the decomposition and transformation of organic matter, improves the composting efficiency of the material, and significantly reduces the odor and harmful gases, thereby reducing environmental pollution.

[0004] For the research of aerobic composting microbial agents, the existing technology mainly focuses on the screening and cultivation of aerobic fermentation microbial strains, but ignores the in-depth exploration and research of microbial agent carriers. Microbial agent carriers are media and substances used to deliver and protect microorganisms to the target environment, and can provide good living conditions for microorganisms. Microbial agent carriers currently mainly include inorganic carriers and organic carriers. Inorganic carriers such as diatomite, zeolite powder, and bentonite are used to load microorganisms due to their superior stable physicochemical properties, but the nutrient elements contained therein are relatively poor, affecting the activity of microorganisms and easily leading to the loss of microorganisms. Organic carriers mainly include bran and straw powder, which can provide suitable conditions for the growth and reproduction of microorganisms. However, organic carriers may be easily affected by the environment and deteriorate, leading to the failure of aerobic fermentation agents. Microbial agent carriers greatly limit the application of microbial agents in the field of aerobic composting. SUMMARY

[0005] In view of the above-mentioned deficiencies in the prior art, the present application aims to provide a high-efficiency aerobic fermentation corncob-based biological conditioner and application thereof, so as to solve the problems of unstable effect of microbial carrier, poor adaptability of carrier, and easy inactivation of microbial carrier in the prior art, thereby improving the fermentation efficiency of the material, promoting the degree of humification, and shortening the fermentation time.

[0006] In order to solve the above technical problems, the present application adopts the following technical solutions:

[0007] The application discloses a high-efficiency corn cob-based biological conditioner prepared by mixing aerobic fermentation microorganisms with a corn cob carrier and then drying the mixture after fermentation.

[0008] Preferably, the mass ratio of the bacterial solution containing the aerobic fermentation microorganisms to the corn cob carrier is 1:(5-8), and the moisture content of the mixture obtained after mixing the bacterial solution with the carrier is adjusted to be 40.0wt%-52.0wt%, and the pH value of the mixture is 6.5-7.5.

[0009] Preferably, the inoculation amount of the microorganisms in the bacterial solution is 0.5wt%-1.0wt%, and the number of viable bacteria in the bacterial solution is at least 1.5x10 9 cfu / mL. The aerobic fermentation microorganisms are activated and expanded in advance, and the active components contained in the aerobic fermentation microorganisms mainly include bacillus subtilis, Bacillus natto, Actinomycete, Saccharomyces cerevisiae and Trichoderma spp. In the first culture, the inoculation amount is 0.5%-1.0%, the culture environment temperature is 35 DEG C, the stirring speed is 180 rpm / min, and the shaking culture is performed for 48-72 hours. When the expansion culture is completed, the number of viable bacteria in the liquid culture medium reaches 1.5-2.0x10 9 cfu / mL, and the culture is ended.

[0010] Preferably, the bacterial solution containing the aerobic fermentation microorganisms is mixed with the corn cob carrier, and then the mixture is cultured at 35 DEG C-48 DEG C for 24-72 hours.

[0011] Preferably, after the fermentation process, the fermentation product is laid on a cool and ventilated place for natural air drying. In order to ensure the activity of the microorganisms and maintain the storage state of the conditioner, the moisture content of the fermentation product is kept at 8.0wt%-12.0wt% during the process. After the fermentation is completed, the product is dried and granulated, and the particle size is 30-60 meshes, so that the biological conditioner is obtained.

[0012] The application further provides an application of the high-efficiency corn cob-based biological conditioner.

[0013] Preferably, the animal excrement is dairy cow excrement.

[0014] Preferably, the composting process is as follows:

[0015] Step 1: Take animal manure, add the biological conditioner, and adjust the C / N ratio in the composting system to (20-30):1;

[0016] Step 2: Perform composting treatment; during the composting treatment, the moisture content of the composting system shall not be less than 50wt%, the total mass of the composting system shall not be less than 15kg, and the composting temperature shall be 60℃-70℃.

[0017] Preferably, in step 2, when the compost temperature reaches above 60°C, the compost pile is turned over every two days.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. This invention uses corn cobs as a carrier matrix for aerobic composting bioconditioners. On the one hand, due to their high organic matter content (91.3%), they can provide essential nutrients and energy for the attached microorganisms, ensuring the quality of corn cob-based bioconditioner products. On the other hand, corn cobs are widely available; compared to other carriers, corn cobs are abundant and easy to obtain, thus helping to reduce production costs. Simultaneously, the relatively stable structure of corn cobs makes them less susceptible to rapid microbial decomposition, maintaining the long-term stability of the inoculant. Due to their unique structure, corn cobs have a high adsorption capacity for ammonia nitrogen and phosphorus, enabling nitrogen and phosphorus retention during composting. The combination of corn cob and biochar enhances this performance and significantly improves the quality of compost products. This invention discovers that mixing corn cob (a porous honeycomb structure providing a physical framework and rapid channels) with homologous corn cob biochar (high specific surface area, abundant micropores) forms a multi-level pore structure. The natural pores of the corn cob ensure aeration and water permeability, while the micropores of the biochar enhance adsorption, fertilizer and water storage capacity, and microbial habitat sites. This homologous mixing achieves pore complementarity (corn cob dominates mesopores, biochar dominates micropores), significantly optimizing the water-holding capacity, pore distribution, and bulk density of the carrier. Its synergistic effect is superior to that of single materials or heterologous biochar combinations.

[0020] 2. This invention further discovers that the various aerobic microorganisms used and the carrier exhibit a better synergistic effect. Because this invention employs multiple aerobic microorganisms, strict control of anaerobic fermentation is required during fermentation. The carrier's excellent permeability facilitates oxygen penetration, thereby disrupting the anaerobic environment. Furthermore, the use of such a complex microbial community with multiple aerobic microorganisms increases the difficulty of growth and metabolism of the entire community on the carrier, as these microorganisms have different growth requirements. The carrier used in this invention has a multi-level porous structure, which allows for the growth of multiple microorganisms. Biological environments provide diverse habitats, which are conducive to the diverse reproduction of microorganisms. Corn cob biochar, as a carrier, possesses pH buffering capacity and the ability to adsorb / slowly release nutrients / inhibitors, helping to stabilize the microenvironment. Furthermore, since corn cob biochar is derived from corn cobs, its surface chemistry (functional groups, charge) is more compatible with the soluble organic matter released from corn cobs, reducing accidental inhibition or adverse adsorption of certain species in the complex microbial community. Therefore, the chemical signals on the surface of the homologous carrier are highly similar to the soluble organic matter, making it easier for complex microbial communities such as Bacillus subtilis and Actinomycetes to form stable communities and shortening the adaptation period. Compared to heterologous biochar carriers (such as coconut shell charcoal), homologous combinations avoid microbial inhibition or community structure disorder caused by differences in surface chemistry. Attached Figure Description

[0021] Figure 1 The changes in temperature of the aerobic compost pile of dairy cow manure treated in Example 2, the blank control group, and Comparative Example 1 are shown.

[0022] Figure 2 The changes in the germination index (GI) of Chinese cabbage seeds treated with aerobic compost of cow manure in Example 2, the blank control group, and Comparative Example 1 are shown.

[0023] Figure 3 The pH changes of aerobic compost material of dairy cow manure treated in Example 2, the blank control group, and Comparative Example 1 were studied.

[0024] Figure 4 Example 2, blank control group, and comparative example 1 were used to treat the NH4+ content in the aerobic composting material of dairy cow manure. + Changes in -N.

[0025] Figure 5 The images show the effects of treating cow manure in Example 2, the blank control group, and Comparative Example 1.

[0026] Figure 6 Example 2, blank control group, comparative example 2 and comparative example 3 show the temperature changes of the compost pile during the treatment of dairy cow manure.

[0027] Figure 7The changes in the seed germination index (GI) of Chinese cabbage in the compost materials at each stage of the dairy cow manure composting process were compared with those in Example 2, the blank control group, Comparative Example 2, and Comparative Example 3.

[0028] Figure 8 Example 2, blank control group, comparative example 2 and comparative example 3 are used to study the pH changes of the compost material at each stage of the dairy cow manure composting process.

[0029] Figure 9 Example 2, blank control group, comparative example 2, and comparative example 3 are used to compare the NH4 content of the compost material at each stage of the dairy cow manure composting process. + Changes in -N.

[0030] Figure 10 Example 2, blank control group, comparative example 2, and comparative example 3 are used to study the changes in organic matter in the compost pile material at each stage of the dairy cow manure composting process.

[0031] Figure 11 Example 2, blank control group, comparative example 2 and comparative example 3 are used to study the changes in the degree of humus in the composting material at each stage of the dairy cow manure composting process. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the present invention are within the scope of protection of the present invention.

[0033] Unless otherwise specified in the specific circumstances, the numerical ranges listed herein include upper and lower limits, as well as all integers and fractions within that range, but are not limited to the specific values ​​listed when the range is defined.

[0034] I. A Highly Efficient Aerobic Fermented Corn Cob-Based Bioconditioner

[0035] The biological conditioner of the present invention is obtained by mixing aerobic fermentation microorganisms with a corn cob-based carrier, fermenting and then drying; wherein, the aerobic fermentation microorganisms are composed of Bacillus subtilis, Bacillus natto, actinomycetes, yeast and trichomycin; the corn cob-based carrier is composed of corn cob and corn cob biochar, and the mass ratio of corn cob to corn cob biochar is (5-10):1, preferably 6:1.

[0036] This invention addresses numerous problems existing in the prior art. The core issues of the prior art include: unreasonable carrier structure; uneven pore distribution and imbalance between air permeability and water retention when using single materials or mixing dissimilar materials, failing to provide an efficient habitat for microorganisms; poor chemical compatibility, with mixing materials from different sources easily leading to large pH fluctuations, uncoordinated release of mineral elements, and significant differences in surface functional groups, affecting microbial colonization and substance adsorption / release; unoptimized activation and propagation conditions for microbial agents, resulting in insufficient viable bacteria and low activity, making stable colonization on the carrier difficult after inoculation; and a lack of targeted control during composting, leading to slow decomposition of organic matter, long composting cycles, severe nitrogen loss, and poor deodorization.

[0037] To address these issues, this invention considers several key aspects: Regarding carrier construction, corn cobs and corn cob biochar are selected as homologous materials and mixed in an optimized ratio. Corn cobs provide macroporous channels and facilitate "fast carbon" transfer, while corn cob biochar provides microporous adsorption sites and facilitates "slow carbon" transfer. The complementary nature of their structures forms a multi-level pore structure. Simultaneously, their homology ensures pH stability, coordinated release of mineral elements, and matching of surface functional groups, enhancing chemical compatibility and microbial ecological adaptability. From a microbial treatment perspective, this invention discovered a composite strain more suitable for the carrier and optimized the activation and propagation conditions for microorganisms, promoting rapid colonization and stable community formation on the carrier. Through these design and optimization measures, it was unexpectedly found that the carrier's physical properties (air permeability, water retention, pore distribution) and chemical properties (pH buffering, nutrient slow release, carbon stability) were significantly optimized, resulting in rapid microbial colonization, high activity, and functional stability.

[0038] In some embodiments of the present invention, the mass ratio of the bacterial solution containing aerobic fermentation microorganisms to the corn cob-based carrier is 1:(5-8), more preferably 1:5. The moisture content of the mixture obtained after mixing the bacterial solution and the carrier is adjusted to be maintained at 40.0 wt%-52.0 wt%, and the pH value of the mixture is 6.5-7.5. The mass ratio of bacterial solution to carrier should not be too high. Excessive bacterial solution may lead to excessively high moisture content, which is detrimental to the subsequent preparation of the biological conditioner. Simultaneously, excessive bacterial solution will result in high microbial activity on the carrier, excessively consuming the carrier's nutrients, which is detrimental to its long-term storage and makes it difficult to control the microbial cultivation time during conditioner preparation. Furthermore, the addition of a large amount of bacterial solution will increase costs, which is detrimental to the promotion of the biological conditioner. Similarly, if the quality of the bacterial solution is too low, the technical effects described in the present invention cannot be achieved.

[0039] In some embodiments of the present invention, the aerobic fermentation microorganisms are first activated and propagated to obtain a bacterial solution. The inoculum amount of microorganisms in the bacterial solution is 0.5 wt% to 1.0 wt%, and the number of viable bacteria in the bacterial solution is at least 1.5 × 10⁻⁶.9 cfu / mL or higher, more preferably (1.5-2.0)×10 9 CFU / mL. The aerobic fermentation microorganisms were pre-activated and propagated, containing mainly *Bacillus subtilis*, *Bacillus natto*, *Actinomycete*, *Saccharomyces cerevisiae*, and *Trichoderma spp*. For the first culture, the inoculum size was 0.5%–1.0%, the culture temperature was 35℃, and the stirring speed was 180 rpm / min for 48–72 h. Upon completion of the propagation, the viable count in the liquid culture medium reached 1.5–2.0 × 10⁻⁶. 9 CFU / mL, incubation ends.

[0040] In some embodiments of the present invention, the corn cob carrier inoculated with the inoculum is cultured in an incubator at a temperature of 35°C. The temperature is monitored in real time and is required to be controlled below 48°C. The culture is carried out for 24-72 hours. The culture ends when obvious mycelia appear on the corn cob carrier.

[0041] In some embodiments of the present invention, after the fermentation process, the fermentation product is spread out in a cool, ventilated place to air dry naturally. To ensure microbial activity and maintain the conditionant's preservation status, the moisture content of the fermentation product is maintained at 8.0 wt%-12.0 wt% during this process. After fermentation, it is dried and granulated to a particle size of 30-60 mesh to obtain the biological conditioner.

[0042] II. Application of a Highly Efficient Aerobic Fermented Corn Cob-Based Bioconditioner

[0043] The biological conditioner of this invention is used for composting animal manure. Preferably, the animal manure is dairy cow manure.

[0044] When the bio-regulator was applied to actual composting, it was found that it produced different effects on different types of waste. When applied to dairy cow manure composting, the bio-regulator effectively promoted the decomposition of organic matter, significantly shortened the composting cycle, reduced nitrogen loss, and enhanced deodorization. It also showed some applicability to composting other organic wastes such as herbivore manure, exhibiting the most comprehensive and significant advantages in the treatment of dairy cow manure, far exceeding the effects of applications using single or non-homogeneous carriers in existing technologies.

[0045] In some embodiments of the present invention, the composting process steps are as follows:

[0046] Step 1: Take animal manure, add the biological conditioner, and adjust the C / N ratio in the composting system to (20-30):1;

[0047] Step 2: Perform composting treatment; during the composting treatment, the moisture content of the composting system shall not be less than 50wt%, the total mass of the composting system shall not be less than 15kg, and the composting temperature shall be 60℃-70℃.

[0048] In some embodiments of the present invention, in step 2, when the compost temperature reaches above 60°C, the compost pile is turned over every two days to promote the rapid decomposition of organic matter in the material and accelerate the composting process. Simultaneously, to ensure microbial activity, the pile temperature is controlled below 70°C, and this is achieved through turning the pile.

[0049] III. Examples and Comparative Examples

[0050] Example 1

[0051] Step 1: After the dried corn cobs and corn cob biochar are crushed and sieved (50 mesh), they are sterilized at 121℃ for 30 min; corn cob-based microbial carriers are constructed with sterilized corn cobs and corn cob biochar at a mass ratio of 6:1.

[0052] Step 2: Activation and propagation treatment of aerobic composting microbial agents. The aerobic fermentation microbial compound agent was inoculated onto the liquid culture medium at an inoculum size of 0.5%–1.0%. The active ingredients of the compound agent mainly consist of Bacillus subtilis, Bacillus natto, Actinomycetes, Saccharomyces cerevisiae, and Trichoderma spp. The culture conditions were: 35℃, stirring speed of 180 rpm / min, culture time of 48 h, and pH of approximately 6.5. Upon completion of propagation, the viable cell count in the liquid culture medium reached 1.5–2.0 × 10⁻⁶. 9 The culture was terminated when the cfu / mL level reached 100%.

[0053] Step 3: The activated and successfully propagated aerobic composting microbial agent is loaded onto the corn cob-based microbial carrier at a ratio of 1:5, while adjusting the moisture content to maintain it between 40.0% and 52.0%.

[0054] Step 4: Incubate the corn cob substrate with bacterial culture in a 35℃ incubator for a period of time. Requirements: Strictly control the temperature (temperature < 48℃); the culture is complete when obvious mycelia appear on the corn cob substrate.

[0055] Step 5: Spread the product obtained in Step 4 in a cool and ventilated place and let it air dry naturally. To ensure the activity of microorganisms and maintain the preservation state, the moisture content of the conditioner must be kept at 8.0% to 12.0%. After drying, granulate the product with a particle size requirement of about 50 mesh to obtain the conditioner.

[0056] Example 2

[0057] The conditioner prepared in Example 1 was used for aerobic composting of dairy cow manure. The specific steps are as follows:

[0058] The dried cow manure was mixed with the conditioner prepared in Example 1, and the C / N ratio was adjusted to approximately 25, with the moisture content of the compost reaching 50%-55%. The mixture was then placed in an aerobic composting reactor and composted at room temperature. The compost was turned over at 4, 6, 8, and 15 days, with samples taken every 2 days. This group is designated as Group C.

[0059] Blank control group CK

[0060] This was an adjustment based on Example 2, the difference being that only corn cobs and dairy cow manure were used for composting, without the addition of aerobic microorganisms; all other steps were exactly the same as in Example 2. This group was designated CK.

[0061] Comparative Example 1

[0062] The method described in Example 2 was adjusted to replace the carrier composed of corn cobs and corn cob biochar in Example 1 with an equal mass of corn cobs. The corn cobs were mixed with aerobic microorganisms and then treated according to the method of Example 1, with all other steps identical to Example 1. The resulting composting agent was used to replace the conditioner in Example 2 with an equal mass of the same agent, with all other steps identical to Example 2. This group is designated as Group S.

[0063] Comparative Example 2

[0064] Based on Example 1, adjustments were made, the difference being that corn cobs were mixed with bamboo charcoal as a carrier, and processed according to the method of Example 1 to obtain a bamboo charcoal-based bioconditioner. Then, the bamboo charcoal-based bioconditioner was used to replace the conditioner in Example 2 by equal mass, and the mixture was used for composting dairy cow manure. This group is designated as Group B.

[0065] Comparative Example 3

[0066] The method described in Example 1 was modified to include the following: corn cobs were mixed with peat moss for composting, and the mixture was processed according to the method in Example 1 to obtain a peat moss-based bioconditioner. Then, the peat moss-based bioconditioner was used to replace the conditioner in Example 2 by an equal mass, and the mixture was used for composting dairy cow manure. This group is designated as Group P.

[0067] IV. Composting Effect

[0068] 1. Example 2: Comparison between the blank control group (CK) and comparative example 1 (S group)

[0069] (1) Measurement results of temperature changes in the compost pile during the composting process

[0070] Temperature during composting Figure 1 As shown, in Example 2 with added corn cob-based bioconditioner, the compost temperature reached 50°C on day 4 and remained at this high temperature for approximately 9 days. After turning the material pile, the temperature fluctuated, but remained relatively stable overall. Compared to the control group and Comparative Example 1 (Group S), Example 2 (Group C) was superior to the other two groups in terms of maintaining high temperature duration, pile temperature, and overall fermentation time. This phenomenon indicates that adding corn cob bioconditioner effectively promoted composting efficiency and shortened fermentation time to some extent.

[0071] (2) Results of seed (Chinese cabbage) germination index (GI) test during composting.

[0072] Seed germination index can be used to determine the degree of compost decomposition, such as Figure 2 As shown, throughout the composting process, the germination index (GI) of the pakchoi seeds in Example 2 with added bioconditioner was significantly higher than that of the control group CK and Comparative Example 1 (S group) without added bioconditioner. When the composting time was 18 days, the GI of the S group was much higher than the harmlessness standard (≥70%), reaching 116.8%. This indicates that the compost product has reached the mature state, and this result shows that adding corn cob-based bioconditioner improved the biosafety of the product.

[0073] (3) Measurement of pH changes in the compost pile during the composting process

[0074] Figure 3 It is evident that during the composting process, in the control group (CK), Comparative Example 1 (S group) with added aerobic composting microbial agents, and Examples 2 and 3 with added corn cob-based bioconditioners, the pH of the compost material showed a significant decreasing trend from 0 to 3 days. The main reason for this phenomenon is likely the conversion of organic matter in the material into organic acids. After a 3-day heating period, the pH of the compost pile rebounded as the composting temperature rapidly increased. This may be due to the volatilization or conversion of organic acids at high temperatures, as well as the decomposition and conversion of some proteinaceous organic matter in the material, releasing ammonia gas and causing the pH to rise. In the later stages of composting, the material was basically decomposed, the temperature decreased, and the pH of the compost tended to stabilize. Throughout the entire composting process, the pH value of Example 2 was significantly lower than that of the control group and Comparative Example 1 (S group), which indirectly verifies that the addition of corn cob-based bioconditioners promoted the humification process of the material.

[0075] (4) Changes in ammonia nitrogen in compost materials at different stages

[0076] Inorganic nitrogen during composting is mainly in the form of NH4. + NH4 exists in the -N form. In this experiment, NH4 is present in both the experimental group and the blank control group. + The content of -N showed a trend of "decreasing-increasing-decreasing", but overall it showed a decrease, as shown in the following results. Figure 4 As shown, when the entire composting process was completed, the NH4 content in group CK was... + -N reduced NH4+ by 20.96% in Comparative Example 1 (Group S). + -N decreased by 61.3% in Example 2 and by the largest amount of 69.64% in Example 2. This indicates that the addition of corn cob-based bioconditioner effectively promoted the life activities of microorganisms, significantly improved aerobic composting efficiency, and accelerated the humification process of organic matter.

[0077] (5) Finished product display of the effect of corn cob-based bioconditioner on promoting aerobic composting of dairy cow manure.

[0078] The product colors of the dairy cow manure after 20 days of aerobic fermentation were as follows: control group CK, comparative example 1 (S group), and Example 2. Figure 5 As shown, the control group had the lightest color, a brownish hue, with a clearly visible fibrous structure, indicating poor decomposition. Comparative Example 1 was dark brown, with the fibrous structure largely gone and a slight aromatic odor, indicating the material was basically decomposed. Example 2 showed a dark brown material with a soft texture and a distinct aromatic odor, indicating a high degree of decomposition. These results demonstrate that adding corn cob-based bioconditioner can improve the aerobic fermentation efficiency of feces, shorten fermentation time, and increase decomposition.

[0079] 2. Compared with Example 2, Comparative Example 2, Comparative Example 3, and the blank control group CK.

[0080] (1) Measurement results of temperature changes in the compost pile during the composting process

[0081] Experiments were conducted on corn cob-cow manure composting with different types of biological conditioners. The temperature change showed a trend of first rising and then falling. Figure 6During the initial stage of composting, the temperature of each treatment group continuously increased. Treatments CK, C, and P all entered the high-temperature period (above 50℃) on day 5 of composting, while treatment B entered the high-temperature period on day 6. Compared to other treatments, treatment B had the highest temperature, reaching 62.67℃, and maintained this high-temperature period for 3 days. Treatment C had the second highest temperature at 60.63℃, but its high-temperature period was prolonged to 5 days. Treatments P and CK had relatively lower temperatures, maintaining around 51℃, and their high-temperature period also lasted for 3 days. The temperature data indicates that the corncob-based bioconditioner (C), prepared by adding corncob biochar and a carrier composed of corncobs, can increase the compost temperature and prolong the duration of high temperatures, thus exhibiting a better effect on promoting compost maturation.

[0082] (2) Results of seed (Chinese cabbage) germination index (GI) test during composting.

[0083] The effects of adding different types of biological conditioners (Group C, Group B, and Group P) on the germination rate of compost seeds, such as... Figure 7 It was found that at the initial stage of composting, the GI values ​​of all treatments were below 80%. After the high-temperature period, on the 10th day of composting, the GI values ​​of all treatments were generally above 80%, indicating that the high temperature reduced pathogens in the compost, thereby increasing the GI value. Throughout the composting process, the GI values ​​of the composting treatments with different types of bioconditioners were generally higher than those of the control group (CK), but this was not statistically significant (P > 0.05). This suggests that compared to the CK group, applying bioconditioners can accelerate the temperature rise of the compost pile by promoting nitrogen conversion and organic matter degradation, thus increasing the GI value. Among them, the treatment with corn cob-based bioconditioner (Group C) had the highest GI value of 141.35%, which was 33.06% higher than that of the CK group, indicating that the addition of bioconditioners can promote the harmlessness of compost.

[0084] (3) Measurement of pH changes in the compost pile during the composting process.

[0085] pH changes during composting treatment Figure 8 It can be seen that at the initial stage of composting, the pH values ​​of each treatment group (CK, C, B, and P) were 8.58, 8.34, 8.47, and 8.34, respectively. During the warming and high-temperature stages of composting, the pH showed an upward trend. This is because in the initial stage of composting, microorganisms decompose large molecular organic nitrogen, forming a large amount of NH4+. + -N is stored within the compost pile, and it was found that the pH increase in groups C and B was greater than that in group CK, indicating that the biochar in groups C and B had a better promoting effect on microbial activity in the early stages of composting. In the later stages of composting, although microbial activity within the pile weakened, some ammonification still occurred, generating a small amount of NH4. + -N is then converted to NO3 through nitration. --N caused the pH to fluctuate, rising and falling. At the end of composting, the pH values ​​of the treatment groups (CK, C, B, and P) were 8.43, 8.19, 8.35, and 8.37, respectively, which are consistent with the pH range of 5.5-8.5 specified in my country's "Organic Fertilizer NY525-2012".

[0086] (4) Changes in ammonia nitrogen in compost materials at different stages

[0087] Adding different types of biological conditioners to compost NH4 + Changes in -N content, such as Figure 9 As shown, the NH4 content of each treatment group (CK group, C group, B group, P group) + -N content shows a trend of increasing during the warming period of composting and decreasing significantly after the high-temperature period. In the early stages of composting, NH4+ content... + The rapid increase in -N content is attributed to enhanced microbial ammoniation under high-temperature conditions, particularly in group C containing NH4+. + The -N content reached its peak at 1.37 g / kg most quickly. This is because the bioconditioner contains a large amount of biochar, which is beneficial for NH4+. + -N has adsorption properties, therefore, NH4 treated with added bioconditioners... + The -N content was higher than that of NH4 in the CK group. + -N content, group C shows an increase in NH4+. + The effect on -N content is more significant; the addition of biological conditioners can effectively retain NH4. + -N content, reducing nitrogen volatilization as NH3. As composting progresses, NH4... + -N is partially converted into organic nitrogen, and partially converted into NO3 by nitrifying bacteria. - -N, resulting in NH4 + -N content continued to decrease. At the end of composting, NH4+ content in each treatment group... + The -N contents were 0.26, 0.39, 0.37, and 0.35 g / kg, respectively. The NH4+ content in all treatments was... + The -N content is less than 0.4 g / kg, which means that the compost has reached the standard of maturity.

[0088] (5) Changes in organic matter in composting materials at different stages

[0089] When different types of biological conditioners were applied to corn cob-cow manure compost, the organic matter content of each treatment group (CK, C, B, and P) showed a basically consistent trend, generally exhibiting a decreasing trend. Figure 10The organic matter underwent rapid biodegradation primarily during the high-temperature period of composting. Subsequently, the degradation rate gradually decreased in each group. Compared to the control (CK) treatment, the addition of the bioconditioner accelerated the degradation of organic matter in the compost. At the end of composting, the organic matter degradation rates of the treatment groups were 15.08%, 24.51%, 19.81%, and 21.06%, respectively. The results indicate that the C group treatment, with the addition of a bioconditioner composed of corn cobs and corn cob biochar as a carrier, had the highest organic matter degradation rate, followed by the B and P treatments, all of which significantly exceeded the CK treatment.

[0090] (6) Changes in the degree of humus in materials at different stages of composting

[0091] The E4 / E6 ratio (absorbance ratio at wavelengths of 465 nm and 665 nm) reflects the quality of humic acid and the degree of aromatization during aerobic composting. The E4 / E6 value decreases with increasing molecular weight and degree of humic acid condensation; therefore, a smaller ratio indicates a higher degree of humification. The changes in E4 / E6 at different time points for each treatment group (CK, C, B, and P) are shown below. Figure 11 As shown, the overall changes in each treatment group exhibited a trend of increasing and then decreasing. On day 10, treatment groups C, B, and P reached their peak values, which were 5.02±0.25, 5.04±0.28, and 5.03±0.02, respectively, while the control group CK reached its peak value (5.03±0.06) after 12 days. In the later stage of composting, the E4 / E6 values ​​of treatment groups C, B, and P were significantly lower than those of CK, indicating that the addition of the biological conditioner effectively enhanced the formation and aromatization of humic acid during the corn cob-dairy cow manure composting process. Among them, the treatment group with corn cob-based biological conditioner (C) showed excellent performance.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit the technical solutions. Those skilled in the art should understand that any modifications or equivalent substitutions to the technical solutions of the present invention without departing from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A highly efficient aerobic fermentation corn cob-based bioconditioner, characterized in that, The bioconditioner is obtained by mixing aerobic fermentation microorganisms with a corn cob-based carrier, fermenting, and then drying; wherein the aerobic fermentation microorganisms are composed of Bacillus subtilis, Bacillus natto, actinomycetes, yeast, and trichomycosis; the corn cob-based carrier is composed of corn cob and corn cob biochar, and the mass ratio of corn cob to corn cob biochar is (5-10):

1.

2. The biological conditioner according to claim 1, characterized in that, The mass ratio of the bacterial solution containing aerobic fermentation microorganisms to the corn cob-based carrier is 1:(5-8). The moisture content of the mixture obtained after mixing the bacterial solution and the carrier is adjusted to maintain the moisture content at 40.0wt%-52.0wt%, and the pH value of the mixture is 6.5-7.

5.

3. The biological conditioner according to claim 2, characterized in that, The inoculum of microorganisms in the bacterial solution is 0.5wt%~1.0wt%, and the number of viable bacteria in the bacterial solution is at least 1.5×10⁻⁶. 9 cfu / mL or higher.

4. The biological conditioner according to claim 2, characterized in that, The bacterial solution containing aerobic fermentation microorganisms was mixed with corn cob-based carrier and cultured at 35℃-48℃ for 24h-72h.

5. The biological conditioner according to claim 2, characterized in that, After the fermentation process, spread the fermented product out in a cool and ventilated place to air dry naturally. During this process, the moisture content of the fermented product is maintained at 8.0wt%-12.0wt%.

6. The application of a highly efficient aerobic fermentation corn cob-based bioconditioner, characterized in that, The biological conditioner according to any one of claims 1-5 is used for animal manure composting.

7. The application according to claim 6, characterized in that, The animal feces mentioned are dairy cow feces.

8. The application according to claim 6, characterized in that, The composting process is as follows: Step 1: Take animal manure, add the biological conditioner, and adjust the C / N ratio in the composting system to (20-30):1; Step 2: Perform composting treatment; during the composting treatment, the moisture content of the composting system shall not be less than 50wt%, the total mass of the composting system shall not be less than 15kg, and the composting temperature shall be 60℃-70℃.

9. The application according to claim 8, characterized in that, In step 2, when the compost temperature reaches above 60°C, the compost pile is turned over every two days.

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