Method for treating industrial microbial fermentation waste by feeding hermetia illucens larvae

Abstract

The invention provides a method for treating industrial microbial fermentation waste by feeding hermetia illucens larvae. The method comprises the following steps: (1) mixing the industrial microbial fermentation waste with straw powder; (2) feeding hermetia illucens larvae with the mixture obtained in the step (1) as feed; and (3) separating out hermetia illucens larvae. The method is good in treatment effect and high in economic benefit, has the advantages of being environmentally friendly, safe and low in cost, not only can convert the industrial microbial fermentation waste into the organic fertilizer, but also can obtain high-quality insect protein.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental protection and industrial waste treatment, and particularly relates to a method for treating industrial microbial fermentation waste by raising black soldier fly larvae. Background Art

[0002] The Black Soldier Fly (Hermetia illucens), also known as the Bright-spotted Flathorn Soldier Fly, belongs to the family Schizophoridae of the order Diptera. It feeds on a wide range of food, mainly on decaying organic matter such as livestock and poultry manure, animal and plant remains, kitchen waste, and agricultural waste. The larvae of the Black Soldier Fly (Black Soldier Fly Larvae) can efficiently transform organic waste and form its own nutrients such as protein and fat. Its protein and oil can be processed as raw materials in the fields of medicine, fine chemicals, and livestock feed. After the transformation of the Black Soldier Fly larvae, not only the utilization of organic waste is realized, but also the pollution and damage of waste to the environment can be reduced, further achieving harmlessness. Therefore, the transformation and degradation of organic waste by the Black Soldier Fly larvae has important resource value and environmental value.

[0003] At present, the research on the harmless treatment and resource utilization of black soldier fly larvae in food waste and livestock manure has gradually matured. The application of its insect protein as feed for poultry, livestock and aquaculture industries, and the use of insect oil in the development of fine chemical products and biodiesel production have also been gradually carried out.

[0004] The treatment of industrial microbial fermentation waste has high operating costs, complex processes, and may cause secondary pollution to the environment. Therefore, it is necessary to develop a method for treating industrial microbial fermentation waste that has good treatment effects, high economic benefits, environmental protection, safety, and low cost. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a new biological treatment method for industrial microbial fermentation waste. The method has good treatment effect, high economic benefit, and has the advantages of environmental protection, safety and low cost. It can not only convert industrial microbial fermentation waste into organic fertilizer, but also obtain high-quality insect protein.

[0006] In one aspect, the present invention provides a method for treating industrial microbial fermentation waste by raising black soldier fly larvae, comprising the following steps:

[0007] (1) mixing industrial microbial fermentation waste and straw powder;

[0008] (2) using the mixture obtained in step (1) as feed to feed black soldier fly larvae;

[0009] (3) Isolate the black soldier fly larvae.

[0010] According to some embodiments of the present invention, the water content of the industrial microbial fermentation waste in step 1 is 60% to 70% by mass. Preferably, the industrial microbial fermentation waste in step 1 is industrial microbial fermentation waste that has been subjected to harmless treatment, such as high-temperature sterilization. Preferably, the crude protein content of the industrial microbial fermentation waste in step 1 is greater than 30% by mass.

[0011] According to some embodiments of the present invention, the particle size of the straw powder in step 1 is 3 mm to 5 mm. Preferably, the straw powder in step 1 is corn straw powder, wheat straw powder or a mixture thereof.

[0012] According to some embodiments of the present invention, the mixing in step 1 is accomplished by stirring.

[0013] According to some embodiments of the present invention, the mass ratio of the industrial microbial fermentation waste to the straw powder in step 1 is 2 to 3:1.

[0014] According to some embodiments of the present invention, the water content of the mixture obtained in step 1 is 40% to 60% by mass, preferably 40% to 50% by mass.

[0015] According to some embodiments of the present invention, the mass ratio of the feed to the black soldier fly larvae in step 2 is 100-150:1.

[0016] According to some embodiments of the present invention, the black soldier fly larvae in step 2 are 3-5 day old black soldier fly larvae with a length of more than 0.5 cm.

[0017] According to some embodiments of the present invention, the feeding temperature in step 2 is 28-32°C, preferably 29-31°C.

[0018] According to some embodiments of the present invention, the humidity of the feeding air in step 2 is 60% to 70% relative humidity.

[0019] According to some embodiments of the present invention, the raising in step 2 is performed under a light intensity of less than 100 Lux.

[0020] According to some embodiments of the present invention, the feeding time in step 2 is 15 to 20 days.

[0021] According to some embodiments of the invention, in step 2, new feed is added every 2 to 5 days.

[0022] According to some embodiments of the present invention, the separated black soldier fly larvae in step 3 are killed at high temperature, dried and crushed to produce high-protein feed, and the remaining material is used as organic fertilizer.

[0023] In another aspect, the present invention provides a feed, which is made from the black soldier fly larvae obtained by the method according to the first aspect of the present invention.

[0024] In yet another aspect, the present invention provides an organic fertilizer made from the remaining material except the black soldier fly larvae obtained by the method according to the first aspect of the present invention.

[0025] According to a specific embodiment of the present invention, the method for treating industrial microbial fermentation waste by raising black soldier flies comprises the following steps:

[0026] 1. The collected solid industrial microbial fermentation waste is sterilized at high temperature, and then placed in a container, and straw powder is added in a ratio of 2 to 3:1 of the mass ratio of industrial microbial fermentation waste to straw powder with a particle size of 3 mm to 5 mm, and the mixture is fully mixed by stirring, and the total water content of the mixture is controlled to be 40% to 50% by mass;

[0027] 2. Pour the mixture into a breeding container as feed, with a feed thickness of 5 to 10 cm, and add 3 to 5-day-old black soldier fly larvae according to a mass ratio of feed to black soldier fly larvae of 100 to 150:1, and raise them under weak light conditions, control the temperature of the raising to be 28 to 32°C, and the humidity to be 60% to 70% RH, add new feed every 2 to 5 days, and raise them for 15 to 20 days;

[0028] 3. Separate the black soldier fly larvae, kill them at high temperature, then dry and crush them to make high-protein feed, and the remaining material is used as organic fertilizer.

[0029] The inventors have found through research that, compared with kitchen waste and livestock excrement, the properties of industrial microbial fermentation waste are more like soil, with poor air permeability. When the black soldier fly larvae are directly used for treatment, the black soldier fly larvae will be directly killed due to lack of oxygen. Mixing the industrial microbial fermentation waste with straw powder can solve this problem. The inventors also noted that the nutritional components of industrial microbial fermentation waste are complex but not comprehensive compared with kitchen waste and livestock excrement. This requires that the black soldier fly larvae be oriented and domesticated in the early stage of the treatment of industrial microbial fermentation waste, so that they can adapt to the special nutritional environment of industrial microbial fermentation waste when the nutrition is not comprehensive, so as to more efficiently treat the industrial microbial fermentation waste. The appropriate amount of straw powder can increase the organic content in the industrial microbial fermentation waste, and ensure the smooth progress of the directional domestication of the black soldier fly larvae. However, in order to avoid the adverse effects of the increase in organic matter brought by the added straw powder, the inventors have also optimized the addition ratio of the straw powder. Furthermore, the inventors optimized the rearing conditions of black soldier fly larvae according to the characteristics of industrial microbial fermentation waste, thereby achieving effective biodegradation of industrial microbial fermentation waste.

[0030] The present invention achieves the following beneficial effects:

[0031] The use of industrial microbial fermentation waste as feed to feed black soldier flies has realized the resource treatment of industrial microbial fermentation waste, in which the black soldier fly larvae feed on the industrial microbial fermentation waste and turn it into insect feces, consuming and degrading the residual organic matter in the industrial microbial fermentation waste, so that the treated residue meets the index of organic fertilizer, solving the problems of large site occupation, long treatment time and environmental pollution in the composting treatment method used in the prior art, and truly achieving pollution-free and resource-based treatment of industrial microbial fermentation waste. The experimental results show that industrial microbial fermentation waste can be converted into organic fertilizer and black soldier fly larvae respectively, which not only solves the problem of pollution generated in the process of industrial microbial fermentation waste treatment, but also obtains high-value insect protein and nutritious organic fertilizer, realizing the resource utilization of industrial microbial fermentation waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, wherein:

[0033] Figure 1 A schematic process flow diagram of a method for treating industrial microbial fermentation waste by raising black soldier fly larvae provided by the present invention. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below in conjunction with specific embodiments. The given examples are only for illustrating the present invention, but not for limiting the scope of the present invention.

[0035] Example 1

[0036] The collected industrial microbial fermentation waste (water content 65% by mass, preparation method see Chinese invention patent application 202010360558.6) was sterilized, mixed evenly with corn stalk powder (particle size 3-5 mm) at a mass ratio of 2:1 and placed in a feeding container as feed, the feeding environment temperature was controlled at 29°C, the humidity was 60% RH, 3-5 day old black soldier fly larvae were added according to the mass ratio of feed to black soldier fly larvae of 150:1, and new feed was added every 4 days, the feeding thickness was controlled at about 10 cm, and the larvae were raised under a light intensity of 80 Lux for 15 days, the old black soldier fly larvae were separated and killed at high temperature, dried and crushed to make high-protein feed, and the remaining materials were used as organic fertilizer. At the same time, industrial microbial fermentation waste without black soldier flies was set in the feeding environment as a control. The test results are shown in Table 1.

[0037] Table 1

[0038]

[0039] * C=(BA) / A×100%

[0040] Example 2

[0041] The collected industrial microbial fermentation waste (water content 67% by mass, preparation method see Chinese invention patent application 202010360558.6) was sterilized, mixed evenly with wheat straw powder (particle size 3-5 mm) at a mass ratio of 3:1 and placed in a feeding container as feed, the feeding environment temperature was controlled at 31°C, the humidity was 70% RH, 3-5 day old black soldier fly larvae were added according to the mass ratio of feed to black soldier fly larvae of 100:1, and new feed was added every 5 days, the feeding thickness was controlled at about 10 cm, and the larvae were raised under a light intensity of 50 Lux for 20 days, the old black soldier fly larvae were separated and killed at high temperature, dried and crushed to make high-protein feed, and the remaining materials were used as organic fertilizer. At the same time, industrial microbial fermentation waste without black soldier flies was set in the feeding environment as a control. The test results are shown in Table 2.

[0042] Table 2

[0043]

[0044] *C=(BA) / A×100%

[0045] Example 3

[0046] This example screens the mass ratio of industrial microbial fermentation waste and straw powder in the method for treating industrial microbial fermentation waste. The mass ratio of industrial microbial fermentation waste and straw powder used and the final moisture content of the mixture of the two are shown in Table 3 (other conditions are the same as Example 2).

[0047] Table 3

[0048]

[0049] Since wheat straw powder is an additional cost and increases the organic matter content in industrial microbial fermentation waste, a mass ratio of 2 to 3:1 was selected, which had a better effect and the lowest content in actual experiments.

[0050] Example 4

[0051] This example screens the final moisture content of the mixture of industrial microbial fermentation waste and straw powder in the method for treating industrial microbial fermentation waste. The mass ratio of the industrial microbial fermentation waste and straw powder used and the final moisture content of the mixture are shown in Table 4 (other conditions are the same as in Example 2).

[0052] Table 4

[0053]

[0054] Considering practical applications, the water content in the mixture is preferably a minimum of 40% to 50% by mass.

[0055] Example 5

[0056] This example screened the final moisture content of the mixture of industrial microbial fermentation waste and straw powder in the method for treating industrial microbial fermentation waste. The mass ratio of the industrial microbial fermentation waste and straw powder used and the final moisture content of the mixture are shown in Table 5.

[0057] Table 5

[0058]

[0059] The + sign indicates the survival rate of larvae raised under the same conditions. The more + signs there are, the greater the number of survivors.

[0060] Combined with actual conditions, it is more reasonable to control the breeding temperature at 28-32℃.

[0061] The above are only several exemplary embodiments of the present invention, and are not intended to limit the present invention in any form. Although the present invention is disclosed as above with preferred embodiments, they are not intended to limit the present invention. Any technician familiar with the profession, without departing from the scope of the technical solution of the present invention, can make some changes or modifications to obtain equivalent or equivalent embodiments using the above disclosed technical content, which belong to the scope of the present invention.

Claims

1. A method for treating industrial microbial fermentation waste by raising black soldier fly larvae, comprising the following steps: (1) mixing industrial microbial fermentation waste and straw powder; (2) using the mixture obtained in step (1) as feed to feed black soldier fly larvae; (3) Isolate the black soldier fly larvae.

2. The method according to claim 1, wherein the water content of the industrial microbial fermentation waste in step 1 is 60% to 70% by mass; preferably, the industrial microbial fermentation waste in step 1 is industrial microbial fermentation waste that has been rendered harmless, such as high-temperature sterilization; preferably, the crude protein content of the industrial microbial fermentation waste in step 1 is greater than 30% by mass.

3. The method according to claim 1 or 2, wherein the particle size of the straw powder in step 1 is 3 mm to 5 mm; preferably, the straw powder in step 1 is corn straw powder, wheat straw powder or a mixture thereof.

4. The method according to any one of claims 1 to 3, wherein the mixing in step 1 is accomplished by stirring; Preferably, the mass ratio of industrial microbial fermentation waste to straw powder in step 1 is 2 to 3:1; Preferably, the water content of the mixture obtained in step 1 is 40% to 60% by mass, preferably 40% to 50% by mass.

5. The method according to any one of claims 1 to 4, wherein the mass ratio between the feed and the black soldier fly larvae in step 2 is 100 to 150:1; Preferably, the black soldier fly larvae in step 2 are 3-5 day old black soldier fly larvae with a length of more than 0.5 cm.

6. The method according to any one of claims 1 to 5, wherein the temperature of the feeding in step 2 is 28 to 32°C, preferably 29 to 31°C; Preferably, the air humidity of the feeding in step 2 is 60% to 70% relative humidity; Preferably, the raising in step 2 is carried out under a light intensity of less than 100 Lux; Preferably, the feeding time in step 2 is 15 to 20 days.

7. The method according to any one of claims 1 to 6, wherein in step 2, new feed is added every 2 to 5 days.

8. The method according to any one of claims 1 to 7, wherein the separated black soldier fly larvae in step 3 are killed at high temperature, dried and crushed to make high-protein feed, and the remaining material is used as organic fertilizer.

9. A feed made from the black soldier fly larvae obtained by the method according to any one of claims 1 to 8.

10. An organic fertilizer made from the remaining materials except the black soldier fly larvae obtained by the method according to any one of claims 1 to 8.

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