Kitchen waste biological treatment emission reduction storage method and application thereof

Abstract

The application discloses a kitchen garbage biological treatment emission reduction storage method and application thereof, and realizes rapid acidification of material storage process and reproduction of odor emission caused by moldy corruption by adding a composite lactic acid bacteria preparation. Meanwhile, before black soldier fly transformation of kitchen garbage, a Bayer conjugation yeast with acidophilic characteristics is added for secondary fermentation, organic acid (VFAs) and ammonia nitrogen in the material are converted into yeast cell protein, the inhibitory effect of free organic acid on the growth and reproduction of black soldier fly larvae is reduced, inorganic ammonia nitrogen is converted into biological organic nitrogen (amino acid, etc.), organic carbon in the material is converted into soluble nutrients (SCOD) which are more easily absorbed by black soldier fly, the transformation of kitchen garbage by black soldier fly larvae is promoted, and ammonia ion volatilization in the transformation process of black soldier fly is reduced. The related technology of the application is helpful for ammonia gas emission reduction and quality improvement and efficiency increase in the process of factory cultivation of black soldier fly.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of biotechnology, and particularly relates to a kitchen waste biological treatment emission reduction and storage method and application thereof. BACKGROUND

[0002] Nutrient-rich kitchen waste can be a resourceful product if handled properly. Kitchen waste is prone to rot and spoilage, and during the stacking process, it generates a large amount of leachate and emits a foul odor, which adversely affects the surrounding atmosphere and water environment, and indirectly affects human health.

[0003] Currently, kitchen waste treatment technologies are divided into biological and non-biological treatment technologies, including incineration, landfill, anaerobic digestion, aerobic composting, and insect conversion. The use of black soldier fly larvae to convert kitchen waste is gradually emerging, and the treatment of kitchen waste by black soldier fly has received widespread attention at home and abroad. Black soldier fly larvae can effectively decompose kitchen waste nutrients using their powerful digestive enzymes and convert them into insect nutrition. The remaining residue is often used as organic fertilizer for soil, which is beneficial to stimulating microbial activity in soil, improving the soil environment, and promoting crop growth. The biological conversion technology based on black soldier fly larvae can effectively treat kitchen waste to synthesize insect protein and oil, which is an important way to solve the problem of waste disposal and feed protein shortage.

[0004] However, the existing technology produces a large amount of odor substances, mainly ammonia, during the storage process of kitchen waste after collection and transportation and after black soldier fly conversion. This is mainly due to the proliferation of a large number of microorganisms in kitchen waste, which decompose nitrogen-containing organic matter in the material and release ammonia, hydrogen sulfide, and other odor components. At the same time, the conversion of kitchen waste by black soldier fly leads to the volatilization of a large amount of inorganic ammonia nitrogen in the material. Therefore, the problem of ammonia and other odor emissions during the storage of kitchen waste and the conversion process of black soldier fly is a technical problem to be solved. SUMMARY

[0005] The present application provides a kitchen waste storage process biological pretreatment deodorization and black soldier fly conversion biological synergistic method, which is composed of the following steps: first, mix the composite lactic acid bacteria preparation (Lactobacillus plantarum, Lactobacillus pentosus, Leuconostoc lactis, Paracaseolovis casei, Lactobacillus rhamnosus) with kitchen waste uniformly and store it, rely on multiple lactic acid bacteria to complete the rapid decomposition and acidification of kitchen waste through multiple degradation enzymes, and then avoid the proliferation of miscellaneous bacteria to achieve stable storage. Second, before the kitchen waste is used as raw material for black soldier fly conversion, the acidophilic Bayers joint yeast is added to further degrade macromolecular nutrients and convert volatile ammonium ions into organic nitrogen, increase the material p H, and enhance the adaptability and palatability of black soldier fly larvae to kitchen waste, which is helpful to ammonia emission reduction and quality improvement and synergistic effect in the process of industrial breeding of black soldier fly.

[0006] Specifically, the present application provides a kitchen waste biological treatment emission reduction storage method, which comprises the following steps,

[0007] Step 1: adding a complex lactic acid bacteria agent to the kitchen waste, and fermenting at room temperature for 5-7 days, wherein the complex lactic acid bacteria agent is composed of Lactiplantibacillus plantarum, Lactiplantibacillus pentosus, Leuconostoc lactis, Lacticaseibacillus paracasei and Lacticaseibacillus rhamnosus;

[0008] Step 2: adding a Zygosaccharomyces bailii agent to the kitchen waste obtained after step 1, and fermenting at room temperature for 1-3 days;

[0009] Step 3: adding Hermetia illucens larvae to the kitchen waste obtained after step 2, and culturing at room temperature until the average weight of the larvae no longer increases.

[0010] As a preferred scheme of the kitchen waste biological treatment emission reduction storage method, in step 1, the concentration of the complex lactic acid bacteria agent is 1.0x10 9 CFU / mL, and the addition amount of the complex lactic acid bacteria agent in the kitchen waste is 1-3wt%.

[0011] As a preferred scheme of the kitchen waste biological treatment emission reduction storage method, in step 1, the complex lactic acid bacteria agent is inoculated into a culture medium in a strain number ratio of 1:1:1:1:1, and cultured at 20-30℃ until the total concentration of the bacterial bodies reaches 1.0x10 9 CFU / mL.

[0012] As a preferred scheme of the kitchen waste biological treatment emission reduction storage method, in step 2, the concentration of the Zygosaccharomyces bailii agent is 1-3.0x10 8The adding amount of the Zygosaccharomyces bailii agent in the kitchen waste is 0.5-2 wt%.

[0013] As a preferred scheme of the kitchen waste biological treatment emission reduction and storage method, in step 2, the Zygosaccharomyces bailii agent is inoculated into a culture medium to activate culture for 48-96 h, and the culture temperature is 20-30 DEG C.

[0014] As a preferred scheme of the kitchen waste biological treatment emission reduction and storage method, in step 3, the kitchen waste obtained after step 2 is adjusted to have a water content of 75-80%, and then the black soldier fly larvae are added.

[0015] As a preferred scheme of the kitchen waste biological treatment emission reduction and storage method, in step 3, the adding amount of the black soldier fly larvae is 1000 per 1 kg of kitchen waste.

[0016] The application provides a kitchen waste storage process odor emission reduction technology and a subsequent black soldier fly conversion process biological efficiency increasing technology. DETAILED DESCRIPTION

[0017] In order to make the above-mentioned purposes, features and advantages of the application more obvious and easy to understand, the specific embodiments of the application will be described in detail below.

[0018] Example 1:

[0019] Mix 5 kg of freshly collected kitchen waste with rice husk powder to adjust the moisture content to 75%, and place it in a blue turnover box for breeding. Add 1000 black soldier fly larvae to 1.0 kg of kitchen waste, spreading the larvae evenly on the surface of the kitchen waste. Place the breeding box in an environment with a room temperature of 30°C for black soldier fly conversion. The conversion is considered complete when the average weight of the larvae stops increasing.

[0020] Without the addition of a rapid acidification compound lactic acid bacteria preparation, kitchen waste can only rely on the lactic acid bacteria in its own material to ferment and produce acid, which is slow and the pH value of the material is higher than 4. At the same time, the concentration of VFAs is only 3872 mg / L. After being transformed by black soldier fly larvae, the average weight of the larvae is 204 mg, the survival rate is 88%, and the total nitrogen loss rate is as high as 19.58%, indicating that a large amount of nitrogen is released into the environment in the form of ammonia.

[0021] Example 2:

[0022] (1) Lactobacillus plantarum ACCC11095, Lactobacillus pentosus ATCC 8041, Leuconostoclactis ATCC 19256, Lactobacillus paracasei ATCC 334, and Lactobacillus rhamnosus ATCC 7469 were activated using MRS medium. Each strain was inoculated at 1.0% (v / v) into MRS medium at an equal colony ratio (colony number ratio of 1:1:1:1:1). The medium was then incubated at 30℃ and 200 rpm. The total bacterial concentration was increased to 1.0 × 10⁻⁶. 9 It was used as a microbial acidifying agent at CFU / mL. The compound lactic acid bacteria agent was added to food waste at an addition ratio of 3.0‰ (W / W) for rapid bio-acidification pretreatment at room temperature for 5 days. After 5 days of room temperature fermentation, the material state was basically stable. The addition of the microbial acidifying agent significantly reduced the pH of the food waste raw material, produced a large amount of volatile organic acids (VFAs), and rapidly achieved material acidification. Ultimately, it prevented the increase in SCOD caused by microbial fermentation during storage, and significantly reduced both ammonium nitrogen and nitrate nitrogen.

[0023] (2) 5 kg of the acidified food waste obtained in step (1) was mixed with rice husk powder to adjust the moisture content to 75%, and placed in a blue turnover box breeding box. According to the ratio of 1000 black soldier fly larvae to 1.0 kg of food waste, the larvae were laid on the surface of the food waste material, and the breeding box was placed in an environment at room temperature of 30°C for black soldier fly conversion. When the average weight of the larvae no longer increased, it was considered that the conversion was completed.

[0024] After the food waste was acidified by the high proportion of 3.0‰ (W / W) complex lactic acid bacteria, the pH of the material was further reduced to 3.52, and the VFAs concentration was further increased, indicating that high concentration of complex lactic acid bacteria preparation can accelerate the acidification of the material, and the SCOD, ammonium nitrogen and nitrate nitrogen concentrations continue to decrease, indicating that the reproduction of miscellaneous bacteria in the material is inhibited. After the black soldier fly conversion, the average weight of the larvae was only 178 mg, the survival rate was greatly affected, only 78%, and the protein content of the larvae was 40.39%, and the total nitrogen loss rate was 11.35%, indicating that the nitrogen released into the environment in the form of ammonia gas was reduced.

[0025] Example 3:

[0026] (1) Lactiplantibacillus plantarum ACCC11095, Lactiplantibacillus pentosus ATCC 8041, Leuconostoclactis ATCC 19256, Lacticaseibacillus paracasei ATCC 334, and Lacticaseibacillus rhamnosus ATCC 7469 strains were activated by MRS medium, each strain was inoculated into MRS medium at a proportion of 1.0% (v / v), and mixed culture was carried out at 30°C and 200 rpm. When the total concentration of bacteria reached 1.0 x 10 9 CFU / mL, it was used as lactic acid bacteria acidification agent. According to the addition ratio of 3.0‰ (W / W), the mixed lactic acid bacteria acidification agent was added to the food waste for room temperature fermentation for 5 days for rapid biological acidification pretreatment.

[0027] After fermentation, the material state was basically stable, the addition of complex lactic acid bacteria preparation could significantly reduce the pH of the food waste raw material, produce a large amount of volatile organic acid (VFAs), and rapidly realize the acidification of the material, thereby preventing the increase of SCOD and the decrease of ammonium nitrogen and nitrate nitrogen caused by microbial fermentation during storage.

[0028] (2) Saccharomyces cerevisiae ATCC 26603 was inoculated into YPD liquid medium for activation culture for 72 hours at a temperature of 30℃ and a rotation speed of 150 rpm. Fermentation continued until the cell concentration reached 3.0 × 10⁻⁶ cells / day. 8 Used as a bacterial agent at CFU / mL;

[0029] Add 1.0‰ (W / W) of Saccharomyces cerevisiae ATCC 26603 microbial agent to the kitchen waste after microbial acidification treatment obtained in step (1), and ferment it at room temperature (30℃) for 48 hours. During the fermentation process, the kitchen waste material is stirred evenly.

[0030] (3) Mix 5 kg of kitchen waste obtained after step (2) with rice husk powder to adjust the moisture content to 75%, and place it in a blue turnover box for breeding. Add 1000 black soldier fly larvae to 1.0 kg of kitchen waste, spread the larvae evenly on the surface of the kitchen waste, and place the breeding box in an environment with a room temperature of 30°C for black soldier fly conversion. The conversion is considered to be completed when the average weight of the larvae no longer increases.

[0031] Black soldier fly larvae were raised using food waste pretreated with acidification and pre-fermented with Saccharomyces cerevisiae as feed. After fermentation with Saccharomyces cerevisiae, the pH of the material remained at 3.55 without a significant increase, while the concentration of volatile fatty acids (VFAs) further increased, indicating that the Saccharomyces cerevisiae produced organic acids under anaerobic conditions. The total organic acid concentration (SCOD) increased to 8914 mg / L. The larval survival rate after black soldier fly transformation was 82%. The larval protein content was 41.26%, the transformation cycle was shortened to 8 days, and the total nitrogen loss rate decreased from 19.58% to 12.98%.

[0032] Example 4:

[0033] (1) Lactobacillus plantarum ACCC11095, Lactobacillus pentosus ATCC 8041, Leuconostoclactis ATCC 19256, Lactobacillus paracasei ATCC 334, and Lactobacillus rhamnosus ATCC 7469 were activated using MRS medium. Each strain was inoculated at 1.0% (v / v) into MRS medium at an equal colony ratio (colony number ratio of 1:1:1:1:1). The medium was then incubated at 30℃ and 200 rpm. The total bacterial concentration was increased to 1.0 × 10⁻⁶.9 CFU / mL as microbial acidification agent. According to the addition ratio of 3.0‰ (W / W), the compound lactic acid bacteria agent was added to the kitchen waste for room temperature fermentation for 5 days for rapid biological acidification pretreatment. After 5 days of room temperature fermentation, the material state was basically stable, the addition of the compound lactic acid bacteria preparation could significantly reduce the pH of the kitchen waste raw material, produce a large amount of volatile organic acid (VFAs), and quickly realize material acidification, thereby preventing the increase of SCOD of the material caused by microbial fermentation during the storage stage, and significantly reducing the ammonium nitrogen and nitrate nitrogen.

[0034] (2) The acidophilic and salt-tolerant Zygosaccharomyces bailii CICC 32190 was inoculated into YPD liquid medium for activation culture for 72 hours, the culture temperature was 30 degrees Celsius, and the rotation speed was 150 rpm. When the fermentation reached a cell concentration of 3.0 x 10 8 CFU / mL as microbial acidification agent.

[0035] The acidophilic and salt-tolerant Zygosaccharomyces bailii CICC 32190 agent was added to the kitchen waste treated by microbial acidification in step (1) at a ratio of 1.0‰ (W / W), and the material was fermented at room temperature of 30°C for 48 hours, and the material was stirred uniformly during the fermentation process.

[0036] (3) 5 kg of kitchen waste treated in step (2) was mixed with rice husk powder to adjust the moisture content to 75%, and placed in a blue turnover box breeding box. According to the ratio of 1000 black soldier fly larvae to 1.0 kg of kitchen waste, the larvae were laid on the surface of the kitchen waste material, and the breeding box was placed in an environment at room temperature of 30°C for black soldier fly conversion. When the average weight of the larvae no longer increased, it was considered that the conversion was completed.

[0037] The kitchen waste treated by acidification pretreatment and Zygosaccharomyces bailii pre-fermentation was used as feed to breed black soldier fly larvae. The yeast fermentation increased the pH of the material to 4.46, and the SCOD increased to 15530 mg / L, effectively alleviating the inhibition of the acidic environment on the growth of black soldier fly larvae. The survival rate of the larvae was significantly improved from 80% to 96%. The protein content of the larvae was increased from 39.22% to 46.27%, the conversion period was shortened to 5 days, and the total nitrogen loss was reduced from 19.58% to 8.78%. This indicates that inorganic ammonium nitrogen is absorbed and converted into organic nitrogen by the yeast, which can effectively reduce the proportion of nitrogen released as ammonia gas in the material.

[0038] Table 1 Physicochemical properties of kitchen waste solid residue

[0039]

[0040] Table 2 Effect of biological pretreatment on conversion of food waste solid residue by Hermetia illucens

[0041]

Claims

1. A kitchen waste biological treatment emission reduction storage method, characterized in that: The method comprises the following steps, Step 1: adding a complex lactic acid bacteria agent into the kitchen waste, and fermenting at room temperature for 5-7 days, wherein the complex lactic acid bacteria agent is composed of Lactobacillus plantarum, Lactobacillus pentosus, Leuconostoc lactis, Lactobacillus paracasei and Lactobacillus rhamnosus; Step 2: adding a Zygonema bainier agent into the kitchen waste obtained after the treatment in step 1, and fermenting at room temperature for 1-3 days; Step 3: adding black soldier fly larvae into the kitchen waste obtained after the treatment in step 2, and culturing at room temperature until the average weight of the larvae no longer increases. In Step 1, the complex lactic acid bacteria agent is to inoculate Lactobacillus plantarum, Lactobacillus pentosus, Leuconostoc lactis, Lactobacillus paracasei and Lactobacillus rhamnosus into the culture medium according to the ratio of the number of colonies 1:1:1:1:1, and cultured at 20-30°C until the total concentration of the bacterial body reaches 1.0x10 9 CFU / mL; In step 2, the concentration of the Bayers Zygorhyllum agent was 1-3.0 x 10 8 The amount of the Bayers Zygorhyllum agent added to the kitchen waste was 0.5-2.0 wt‰.

2. The kitchen waste biological treatment and emission reduction storage method according to claim 1, characterized in that: The concentration of the complex lactic acid bacteria agent in Step 1 was 1.0 x 10 9 The concentration of the complex lactic acid bacteria agent in Step 1 was 1.0 x 10 9 The concentration of the complex lactic acid bacteria agent in Step 1 was 1.0 x 10 9 The concentration of the complex lactic acid bacteria agent in Step 1 was 1.0 x 10 9 The concentration of the complex lactic acid bacteria agent in Step 1 3. The kitchen waste biological treatment and emission reduction storage method according to claim 2, characterized in that: In step 2, the Zygonema bainier agent is inoculated into a culture medium to activate and culture for 48-96 hours, and the culture temperature is 20-30 DEG C.

4. The kitchen waste biological treatment and emission reduction storage method according to any one of claims 1-3, characterized in that: In step 3, the kitchen waste obtained after the treatment in step 2 is adjusted to have a moisture content of 65-80%, and then the black soldier fly larvae are added.

5. The kitchen waste biological treatment and emission reduction storage method according to claim 4, characterized in that: In step 3, the black soldier fly larvae are added in an amount of 1000 per 1 kg of kitchen waste.

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