Resource utilization method of kitchen waste concentrated solution

Abstract

The invention relates to the technical field of waste treatment, in particular to a resource utilization method of a kitchen waste concentrated solution. Comprising the following steps: performing three-phase separation treatment on the kitchen waste, and collecting a liquid phase; sequentially carrying out first fermentation treatment and distillation treatment on the liquid phase to obtain a concentrated solution; the concentrated solution is used for feeding saprophytic insect larvae. According to the resource utilization method, a new way for utilizing the concentrated solution is provided, the concentrated solution is used for feeding saprophytic insect larvae, on one hand, the utilization mode can be used for efficiently and harmlessly treating the concentrated solution, waste is not needed, and the environmental burden of kitchen garbage is reduced; on the other hand, in the feeding process, excrement of the insect larvae can be used as high-quality organic agricultural fertilizer; and on the other hand, the grown adults are rich in protein and fat, can be used as high-quality animal feed or feed raw materials, and have extremely high economic value. Therefore, the method provided by the invention has extremely high environmental protection value and economic value.

Description

Technical Field

[0001] The present application relates to the technical field of waste treatment, and in particular to a method for resource utilization of kitchen waste concentrate. Background Art

[0002] The most common way to centrally process kitchen waste is to sort and crush it before it enters a three-phase centrifuge to separate the solid, liquid and oil phases. The oil is recycled and used to process biodiesel, which is one of the main sources of income for kitchen waste treatment projects; the liquid and solid phases are also rich in organic matter, which can be used as resources.

[0003] Solid residue (abbreviated as solid residue) contains insoluble organic matter, such as protein, polysaccharides, etc., which can be sent to the anaerobic digestion system to produce methane, or made into protein feed as a substitute for fish meal, or used to raise insects.

[0004] The liquid phase (also called three-phase centrifuge) is rich in soluble organic matter, which can generate small molecular organic matter such as acetic acid, ethanol, propionic acid and propanol through directional fermentation. After fermentation, distillation treatment is carried out, and these small molecular organic matter will evaporate, and then condensation treatment can be carried out to produce liquid carbon sources. These liquid carbon sources are rich in small molecular organic matter and can be used as an additional carbon source for sewage treatment plants or other fields. However, the bottom liquid (referred to as concentrated liquid) remaining after distillation contains a large amount of oil, suspended particulate matter, and a large amount of organic nitrogen, nitrogen ammonia, phosphate, sodium ions and chloride ions, which are wastes and easily cause secondary pollution. However, these complex components make it difficult to handle and the processing cost is high. There is a lack of effective utilization methods. They can only be discarded after complicated procedures and expensive harmless treatment, which is costly and cannot generate economic value. Summary of the invention

[0005] The purpose of the present application is to provide a method for resource utilization of concentrated liquid obtained from kitchen waste, aiming to solve the technical problem in the prior art that the concentrated liquid remaining after fermentation and distillation of three-phase centrifugal liquid from kitchen waste cannot be effectively utilized.

[0006] In order to achieve the above application purpose, the technical solution adopted in this application is as follows:

[0007] In a first aspect, the present application provides a method for resource utilization of concentrated liquid obtained from kitchen waste, comprising the following steps:

[0008] After subjecting the food waste to three-phase separation, the liquid phase is collected;

[0009] The liquid phase is subjected to a first fermentation treatment and a distillation treatment in sequence to obtain a concentrated liquid;

[0010] The concentrate is used to feed saprophytic insect larvae.

[0011] The resource utilization method of the present application proposes a new way to utilize the concentrated liquid, in which the concentrated liquid is used to feed saprophytic insect larvae. The organic matter and salts rich in the concentrated liquid can be used as nutrients required for the growth of insect larvae. Moreover, these insect larvae are saprophytic insect larvae, which can efficiently convert the organic waste in the concentrated liquid into their own nutrients such as protein and fat, and eventually grow into adults. On the one hand, this utilization method can efficiently and harmlessly treat the concentrated liquid without waste, reducing the environmental burden of kitchen waste; on the other hand, during the feeding process, the excrement of the insect larvae can be used as high-quality organic fertilizer; on the other hand, the grown adults are rich in protein and fat, which can be used as high-quality animal feed or fertilizer, thereby obtaining high value-added products with extremely high economic value. Therefore, the method of the present application has extremely high environmental value and economic value. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0013] Figure 1 This is a sample diagram of the concentrated solution obtained in step S2 of Example 1 of the present application;

[0014] Figure 2 This is a schematic diagram of hatching black soldier fly larvae in step S3 of Example 1 of the present application;

[0015] Figure 3 It is a schematic diagram of obtaining a solid phase by three-phase centrifugation in Example 6 of the present application;

[0016] Figure 4 This is a schematic diagram of feeding black soldier flies to obtain adults in Example 6 of the present application. DETAILED DESCRIPTION

[0017] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0018] In this application, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0019] In this application, "at least one" means one or more, "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items.

[0020] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0021] The weight of the relevant components mentioned in the embodiment description of the present application can not only refer to the specific content of each component, but also represent the proportional relationship between the weights of the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the embodiment description of the present application, it is within the scope disclosed in the embodiment description of the present application. Specifically, the mass in the embodiment description of the present application can be μg, mg, g, kg and other mass units known in the chemical industry.

[0022] The terms "first" and "second" are used only for descriptive purposes to distinguish objects such as substances from each other, and should not be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. For example, without departing from the scope of the embodiments of the present application, the first XX may also be referred to as the second XX, and similarly, the second XX may also be referred to as the first XX. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0023] Glossary: ​​Kitchen waste: The kitchen waste in this application refers to garbage and kitchen scraps generated in daily life and food processing, catering services, unit catering and other activities, including discarded vegetable leaves, leftovers, leftover rice, fruit peels, egg shells, tea dregs, bones (chicken bones, fish bones), etc. Its main sources are home kitchens, restaurants, hotels, canteens, markets and other industries related to food processing.

[0024] Three-phase centrifugal liquid (liquid phase): After the three-phase separation of kitchen waste, solid phase, oil phase and liquid phase are obtained. The liquid phase here is a common term in the industry, which is a parallel term with the oil phase and does not include the oil phase. However, after the three-phase separation of kitchen waste, it is inevitable that the liquid phase still contains organic matter, rather than an inorganic solution mixture. This is the consensus in the industry. Therefore, liquid phase and oil phase are terms within the industry, rather than liquid phase and oil phase distinguished from the perspective of chemical disciplines.

[0025] A first aspect of an embodiment of the present application provides a method for resource utilization of kitchen waste concentrate, comprising the following steps:

[0026] S10: After the kitchen waste is subjected to three-phase separation treatment, a liquid phase is collected;

[0027] S20: subjecting the liquid phase to a first fermentation treatment and a distillation treatment in sequence to obtain a concentrated liquid;

[0028] S30: The concentrate is used to feed saprophytic insect larvae.

[0029] The method of resource utilization in the embodiment of the present application proposes a new way to utilize the concentrated solution, and the concentrated solution is used to feed saprophytic insect larvae. The organic matter and salt rich in the concentrated solution can be used as the nutrients required for the growth of insect larvae. Moreover, these insect larvae are saprophytic insect larvae, which can efficiently convert the organic waste in the concentrated solution into its own nutrients such as protein and fat, and eventually grow into adults. On the one hand, this utilization method can efficiently and harmlessly treat the concentrated solution without waste, reducing the environmental burden of kitchen waste; on the other hand, during the feeding process, the excrement (insect feces / insect sand) of the insect larvae can be used as high-quality organic agricultural fertilizer; on the other hand, the grown adults are rich in protein and fat, which can be used as high-quality animal feed or feed additives, thereby obtaining high value-added products with extremely high economic value. Therefore, the method of the embodiment of the present application has extremely high environmental value and economic value.

[0030] Step S10 is a step of performing three-phase centrifugation. In the exemplary embodiment, the kitchen waste can be sorted, crushed, and heated before being transferred to a three-phase centrifuge for centrifugal treatment to separate the oil phase, liquid phase, and solid phase, and the liquid phase is collected.

[0031] Step S20 is a step for treating the liquid phase. The liquid phase (three-phase centrifuge) is rich in soluble organic matter. The first fermentation treatment can be anaerobic fermentation. The microorganism can select the endogenous microorganism of the substrate. The temperature is a medium temperature of 30 to 40 ° C, and the time can be about 4 to 5 days. In addition, it can also be a method such as ethanol directional fermentation. After the first fermentation treatment, small molecular organic substances such as acetic acid, ethanol, propionic acid and propanol can be generated. After the first fermentation treatment, distillation treatment is carried out, and these small molecular organic substances will evaporate. Then, condensation treatment is carried out to produce liquid carbon sources. These liquid carbon sources are rich in small molecular organic substances and can be used as an additional carbon source for sewage treatment plants or other fields. The remaining bottom liquid of the kettle after distillation is the concentrated liquid.

[0032] Step S30 is a step of using the concentrated liquid to feed insect larvae.

[0033] The water content of the concentrated solution obtained by steps S10 and S20 is 70% to 80%. Figure 1As shown, it is generally brown or dark brown in appearance, rich in various organic substances such as oil and salt, with a complex composition. Existing technology cannot effectively utilize it as a resource. The smell is similar to butyric acid or valeric acid, the touch is similar to vegetable oil, it is not easy to spoil, and the preservation method is sealed storage at room temperature.

[0034] In some embodiments, the insect larvae include at least one of black soldier flies (larvae), fly maggots (larvae), mealworms (larvae), and cockroaches, and the black soldier flies are optional. These insect larvae are saprophytic insect larvae, which can use the concentrated liquid as feed and convert it into their own nutrients, with high conversion rate and high output.

[0035] In some embodiments, the concentrated liquid can be used for feeding in the following manner (1), comprising the following steps:

[0036] S31: providing a solid support material, attaching the insect larvae to the support material, and adding the concentrate to the support material for feeding the insect larvae.

[0037] The method (1) is to directly use the concentrated liquid as feed for feeding, and at this time some solid support materials need to be added for the insect larvae to attach. In some embodiments, the support materials may include at least one of agricultural scraps, wood chips, mushroom waste, plastic particles, and rubber particles; wherein the agricultural scraps may include at least one of corn stalks, rape straw, soybean straw, wheat straw, peanut straw, rice straw, corn cobs, peanut shells, and rice husk powder. These support materials are mainly waste, which can be recycled, and are cheap and in large supply. The support materials can be crushed first, and crushed to a particle size of more than 20 meshes, which is helpful for the attachment and feeding of insect larvae, and facilitates the subsequent separation of insect bodies and residues.

[0038] When adding the concentrate, you can choose to add it in small amounts multiple times, and each addition should be based on when the insect larvae are about to finish eating the feed, rather than adding it all at once or twice. On the one hand, considering that the concentrate is a liquid, adding all the feed once or twice will cause the feeding environment to be too dilute, and the insect body may be submerged and unable to survive; on the other hand, adding too much feed in a short period of time will make it difficult for the insect larvae to consume all of it at once, causing the concentrate to gradually corrupt. Adding it in small amounts multiple times can keep the concentrate fresh, allowing the insect larvae to continue to ingest fresh concentrate and consume the concentrate evenly, so that the growth is more stable. The total amount of feed can be 1.5 kg of eggs for 1 ton of concentrate, and the output can reach 200-300 kg of larvae for 1 ton of concentrate.

[0039] The above agricultural waste or sawdust is used as the support material, the feeding time is 8 to 15 days, the insect body length can reach 10 to 15 mm after 8 days of feeding, and the weight ratio of the concentrate to the insect larvae to produce adults (material / insect ratio) is 1: (0.10 to 0.18), and in the exemplary example, it can include but is not limited to any value of 1: 0.10, 1: 0.12, 1: 0.14, 1: 0.16, 1: 0.18 or the range between any two values. In the embodiment, after 8 days of feeding, the concentrate is continued to be added to extend the feeding time, the larvae will continue to grow and become pupae, and a small number of pupae can emerge.

[0040] In the demonstration, when mushroom waste was used as the support material, the insects began to die from the third day. When plastic particles were used as the support material, the insects survived but grew slowly. By the eighth day, most of the insects were 7 mm long, and a few grew to 12 mm. By the 15th day, most of the insects were 10 mm long. When rubber particles were used as the support material, the insects fled or died one after another. This is mainly because these support materials lack necessary nutrients and contain toxic substances.

[0041] Therefore, the supporting material may be the above-mentioned agricultural waste or sawdust, and on the 8th day of feeding, since the supporting material has a small particle size and is relatively dry, the insect bodies and the residues are easily separated. Continuing to add material or extending the feeding time may make it difficult to separate the insect bodies and the residues.

[0042] In some embodiments, the concentrated liquid can be used for feeding in the following manner (2), comprising the following steps:

[0043] S32: subjecting the concentrated liquid to a second fermentation process, and using the fermentation product to feed insect larvae;

[0044] The method (2) subjects the concentrated liquid to a second fermentation treatment, which is beneficial for converting the organic matter in the concentrated liquid into a form that is easier for insect larvae to digest and absorb, and is beneficial for the insect larvae to eat and grow. The second fermentation treatment can be aerobic fermentation or anaerobic fermentation, and lactic acid fermentation in anaerobic fermentation can be selected. The advantage of lactic acid fermentation is that the process is simple, and more importantly, it can hydrolyze the cellulose and other difficult-to-degrade organic matter in the concentrated liquid into smaller molecular weight lactic acid, amino acids, hemicellulose, sugar substances and other components, which is beneficial for the insect larvae to eat and grow. Among them, the temperature of the second fermentation treatment can be 30 to 45°C; the time of the second fermentation treatment can be 24 to 48 hours.

[0045] In addition, grain byproducts such as bran and wheat bran can be added during the second fermentation process. These grain byproducts can provide additional organic matter and nutrition for the second fermentation process, making the products of the second fermentation process more conducive to the feeding and growth of insect larvae. Therefore, the raw materials for the second fermentation process may include concentrated liquid, grain byproducts, and lactic acid bacteria. The mass ratio of concentrated liquid, grain byproducts, and lactic acid bacteria is (3-10): (2-10): 1. In the exemplary example, it may include but is not limited to any ratio of (3 or 4 or 5 or 7 or 10): (2 or 3 or 5 or 7 or 10): 1 or a range between any two ratios.

[0046] In the method (2), the time for feeding the insect larvae can be 5 to 7 days. Through the method (2), the weight ratio of the fermentation product used to the adult insects produced by the insect larvae is 1:(0.2 to 0.3). In the exemplary embodiment, it can include but is not limited to any ratio of 1:0.2, 1:0.25, 1:0.28, 1:0.3 or a range between any two ratios. It can be seen that feeding insect larvae in this way also has a higher output.

[0047] In some embodiments, the concentrated liquid can be used for feeding in the following manner (3), comprising the following steps:

[0048] S33: collecting the solid phase after the three-phase centrifugation treatment, mixing the concentrated liquid with the solid phase, and using the obtained mixture to feed insect larvae.

[0049] The conventional treatment method for the solid phase obtained after three-phase centrifugation of kitchen waste is anaerobic treatment to produce methane, or to make protein feed, which requires additional equipment and space. There are also studies that use the solid phase to feed insect larvae. According to research, the method (3) uses the solid phase after three-phase centrifugation of kitchen waste in conjunction with the above-mentioned concentrated liquid to feed insect larvae, so that the solid phase can also be utilized without the need for additional equipment and space, and the synergistic feeding is beneficial to the growth of insect larvae and increases output. In the demonstration example, the moisture content of the solid phase is about 75% to 80%, the appearance is gray-brown, it emits the smell of rotten food, and it feels like meat filling and is very easy to rot. The solid phase can be selected from the discharge port of the three-phase separator on the same day, or the solid phase stored in the refrigerator for no more than 1 day.

[0050] In the above method (3), the mass ratio of the solid phase to the concentrated liquid is (1-4):1. In the exemplary embodiment, it may include but is not limited to any value of 1:1, 2:1, 3:1, 4:1 or a range between any two values. The solid-liquid ratio in these mixtures is reasonable, which is more conducive to the insect larvae's feeding, absorption and growth. The feeding time can be 5-8 days. If the feed is continued or the feeding time is extended, it may be difficult to separate the insect body from the residue. According to the above feeding method, the weight ratio of the mixture of the solid phase and the concentrated liquid to the adult insects produced by the insect larvae (feed / insect ratio) can reach 1:(0.24-0.32), which has a very significant output ratio.

[0051] In the demonstration, taking the feeding of black soldier fly larvae as an example, feed can be added multiple times during the feeding process. When the solid phase and the concentrated liquid mass ratio are prepared according to 4:1, the final feed / insect ratio is 1: (0.24-0.28), and the average insect body length is 20mm. When the solid phase and the concentrated liquid mass ratio are prepared according to 3:1, the final feed / insect ratio is 1: (0.26-0.28), and the average insect body length is 20mm. When the solid phase and the concentrated liquid mass ratio are prepared according to 2:1, the final feed / insect ratio is 1: (0.3-0.32), and the average insect body length is 20mm. When the solid phase and the concentrated liquid mass ratio are prepared according to 1:1, the insect larvae will escape from the breeding tray because the feed is too dilute.

[0052] In the method (3), the solid phase and the concentrated liquid are mixed and then fed to the insect larvae. Regardless of whether it is compared with direct feeding with the solid phase or direct feeding with the concentrated liquid in the method (1), the method (3) is conducive to further reducing the feed / insect ratio, indicating that the concentrated liquid and the solid phase can supplement each other's nutrients, and the mixing of the concentrated liquid and the solid phase makes the solid residue softer, which is convenient for the insect larvae to drill into.

[0053] The above steps S31, S32, and S33 are in parallel relationship, and any one of the three methods can be adopted. When feeding insect larvae, they can be fed in a breeding tray, and the feeding method is two or more feedings, and the feeding amount is that the insect larvae basically eat it before the next feeding. The breeding density is 5.5g to 6g larvae / square meter. After the adults are obtained through breeding, the insect sand and adults are separated and harvested. Both insect sand and adults are high value-added products that can be sold to the outside to obtain economic value. At the same time, the concentrate is also reasonably utilized, reducing environmental pressure, and there is no need to spend extra money on site equipment for complex harmless treatment.

[0054] The following describes the invention in conjunction with specific embodiments.

[0055] Example 1

[0056] This embodiment provides a method for resource utilization of concentrated liquid obtained from kitchen waste, comprising the following steps:

[0057] S1: After the kitchen waste is separated into three phases, the liquid phase is collected;

[0058] S2: The liquid phase is subjected to fermentation and distillation treatments in sequence to obtain Figure 1 The concentrate shown; the type of fermentation treatment is anaerobic fermentation, the microorganisms are endogenous microorganisms of the substrate, the fermentation temperature is 30°C, the residence time of the fermentation treatment is about 4 days, and the fermentation mode is batch fermentation;

[0059] S3: Incubate the black soldier fly eggs in warm and ventilated conditions, and feed them with wheat bran and chick feed as brooding material after hatching. The weight ratio of eggs, wheat bran, chick feed and water is 1:10:10:40. After the brooding material is prepared, evenly sprinkle the hatched black soldier fly larvae on the surface of the brooding material and place it in a ventilated and cool place away from light. After 4 to 5 days, the insect body will grow to 4mm, and the black soldier fly larvae are obtained. Figure 2 As shown;

[0060] S4: adopt the above method (1), provide solid support material, attach black soldier fly larvae to the support material, add concentrated liquid to the support material for feeding black soldier fly larvae; the support material is a mixture of 9 agricultural waste materials including corn stalks, rape straw, soybean straw, wheat straw, peanut straw, rice straw, corn cobs, peanut shells and rice husk powder crushed to 20 mesh and sawdust. When feeding, add concentrated liquid in small amounts and multiple times, 3 to 4 times a day, and the weight increases day by day according to the growth of the insect body, but does not exceed 5% of the total input materials per unit insect breeding area. After 15 days of feeding, the breeding density is 5.5g-6g larvae / square meter.

[0061] Example 2

[0062] This embodiment provides a method for resource utilization of concentrated liquid made from kitchen waste, which is different from Embodiment 1 only in that the support material in step S4 is replaced with mushroom waste, and the rest is the same.

[0063] Example 3

[0064] This embodiment provides a method for resource utilization of concentrated liquid made from kitchen waste, which is different from Embodiment 1 only in that the supporting material in step S4 is replaced with plastic particles, and the rest is the same.

[0065] Example 4

[0066] This embodiment provides a method for resource utilization of concentrated liquid obtained from kitchen waste, which is different from Embodiment 1 only in that the supporting material in step S4 is replaced with rubber particles, and the rest is the same.

[0067] Example 5

[0068] This embodiment provides a method for resource utilization of concentrated liquid obtained from kitchen waste, which differs from Embodiment 1 only in that: Step S4 is changed to the above-mentioned method (2), and the concentrated liquid, agricultural by-products such as bran and wheat bran, and lactic acid bacteria are fermented in a mass ratio of 5:5:1, the fermentation temperature is 35°C, the fermentation environment is anaerobic, the fermentation residence time is 3 days, and the fermentation mode is batch fermentation. The fermentation product is used to feed black soldier fly larvae. Parameters such as feeding amount and feeding frequency are also the same as those in Embodiment 1.

[0069] Example 6

[0070] This embodiment provides a method for resource utilization of concentrated liquid obtained from kitchen waste. The difference from the embodiment 1 is that the step S4 is changed to the above-mentioned method (3), and the solid phase obtained by three-phase centrifugation in step S1 is also collected. Figure 3 As shown. And step S4 is changed to mixing the solid phase and the concentrated liquid in a mass ratio of 4:1 to obtain a mixture, adding the mixture to the breeding plate, and scattering the black soldier fly larvae on the surface after the first feeding, without turning it over, and adding the second feeding after the black soldier flies have basically eaten it. The black soldier flies will turn over and flatten the feed by themselves. The parameters such as feeding amount and feeding frequency are also the same as those in Example 1, and the obtained adults are as follows Figure 4 shown.

[0071] Example 7

[0072] This embodiment provides a method for resource utilization of concentrated liquid obtained from kitchen waste, which is different from Embodiment 6 only in that the mass ratio of the solid phase to the concentrated liquid is changed from 4:1 to 3:1, and the rest is the same.

[0073] Example 8

[0074] This embodiment provides a method for resource utilization of concentrated liquid obtained from kitchen waste, which is different from Embodiment 6 only in that the mass ratio of the solid phase to the concentrated liquid is changed from 4:1 to 2:1, and the rest is the same.

[0075] Example 9

[0076] This embodiment provides a method for resource utilization of concentrated liquid obtained from kitchen waste, which is different from Embodiment 6 only in that the mass ratio of the solid phase to the concentrated liquid is changed from 4:1 to 1:1, and the rest is the same.

[0077] Comparative Example 1

[0078] In this comparative example, the solid phase after three-phase centrifugation in step S1 of Example 1 was collected and directly used to feed black soldier fly larvae, with feeding divided into two times, on the first day and the fourth day.

[0079] Comparative Example 2

[0080] The difference between this comparative example and comparative example 1 is that the feeding is changed from two times to multiple times.

[0081] Comparative Example 3

[0082] The difference between this comparative example and Example 1 is that the fermentation and distillation steps of step S2 are not included, and the liquid phase of step S1 is directly used as feed for feeding the black soldier fly larvae of step S4. The parameters such as feeding amount and feeding frequency are also the same as those of Example 1.

[0083] The differences between Examples 1 to 9 and Comparative Examples 1 to 3 are shown in Table 1.

[0084] Table 1

[0085]

[0086]

[0087] It can be seen from Comparative Example 1 and Comparative Example 2 that the solid phase will rot due to the long time interval between the two feedings in Comparative Example 1, and the black soldier flies prefer the fresh food in Comparative Example 2. Compared with only two feedings in Comparative Example 1, multiple feedings in Comparative Example 2 can reduce the feed / worm ratio and increase the output, indicating that the degree and proportion of solid residue corruption are reduced, and the thickness of the feed is reduced, which is beneficial to the breathing of black soldier flies, thereby increasing the feeding rate of black soldier flies.

[0088] In comparative example 3, the three-phase centrifuge liquid is directly used for feeding, and the larvae will suffocate and die on a large scale due to the high water content (≥95%), and a large amount of auxiliary materials need to be added, and the nutritional value is not high, the worm production rate is low, and the effective ingredients in the centrifuge liquid cannot be classified and utilized, which easily causes a waste of resources.

[0089] Compared with the prior art of raising black soldier flies using only solid phase in comparative example 1, examples 6 to 9 adopt the above-mentioned method (3) to mix the solid phase and the concentrated liquid to raise black soldier flies, which can further reduce the feed / insect ratio and improve the output. Moreover, by adjusting the ratio of the solid phase to the concentrated liquid, the feed / insect ratio can reach a maximum of 1: (0.3-0.32), which is the method with the highest output at present, indicating that the nutrients in the concentrated liquid and the solid phase complement each other, and the addition of the concentrated liquid makes the solid phase softer and easier for black soldier flies to drill into.

[0090] Examples 1 to 4 adopt the above-mentioned method (1), using only concentrated liquid as a nutrient source to feed black soldier flies. Among them, when mushroom waste, plastic particles or rubber particles are used as support materials, black soldier flies grow slowly or die, indicating that these support materials lack necessary nutrients and contain toxic substances. When agricultural waste and sawdust are used as support materials, black soldier flies can grow and eclode, but the time consumed is much longer than the method of mixing solid phase and concentrated liquid, indicating that these support materials can provide a small amount of nutrients, but are not enough to support the normal growth of black soldier flies.

[0091] Example 5 adopts the above-mentioned method (2), and the product of fermentation of the concentrate with grain by-products and lactic acid bacteria is used to feed black soldier flies, which achieves the coordinated comprehensive utilization of various organic waste resources, reduces resource waste, and makes the best use of resources. In addition, the high-quality animal protein of insect protein can be used as a substitute product after bioconversion.

[0092] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for resource utilization of kitchen waste concentrate, characterized in that: The steps include: After subjecting the food waste to three-phase separation, the liquid phase is collected; The liquid phase is subjected to a first fermentation treatment and a distillation treatment in sequence to obtain a concentrated liquid; The concentrate is used to feed saprophytic insect larvae.

2. The method according to claim 1, characterized in that: The concentrated liquid is used for feeding in any one of the following ways (1) to (3): (1) providing a solid support material, attaching the insect larvae to the support material, and adding the concentrated liquid to the support material for feeding the insect larvae; (2) subjecting the concentrated liquid to a second fermentation process, and using the fermentation product to feed the insect larvae; (3) collecting the solid phase after the three-phase centrifugation treatment, mixing the concentrated liquid with the solid phase, and using the obtained mixture to feed the insect larvae.

3. The method according to claim 2, characterized in that: In the method (1); The support material includes at least one of straw, sawdust, mushroom waste, plastic particles, and rubber particles; And / or, the particle size of the support material is greater than 20 mesh.

4. The method according to claim 2 or 3, characterized in that: In the method (1); Feeding time is 8 to 15 days; And / or, the weight ratio of the concentrated liquid to the adult insects produced by the insect larvae is 1:(0.10-0.18).

5. The method according to claim 2, characterized in that: In the method (2), the second fermentation treatment includes lactic acid fermentation; The temperature of the second fermentation treatment is 30-35°C; And / or, the second fermentation treatment time is 24 to 48 hours; And / or, the raw materials for the second fermentation treatment include the concentrated liquid, cereal by-products, and lactic acid bacteria, and the mass ratio of the concentrated liquid, the cereal by-products, and the lactic acid bacteria is (3-10):(2-10):

1.

6. The method according to claim 2 or 5, characterized in that: In the method (2); The feeding period is 5 to 7 days; And / or, the weight ratio of the fermentation product to the adults produced by the insect larvae is 1:(0.2-0.3).

7. The method according to claim 2, characterized in that: In the method (3), the mass ratio of the solid phase to the concentrated liquid is (1-4):

1.

8. The method according to claim 2 or 7, characterized in that: In the method (3); The feeding period is 5 to 8 days; And / or, the weight ratio of the mixture to the adults produced by the insect larvae is 1:(0.24-0.32).

9. The method according to any one of claims 1, 2, 3, 5, and 7, characterized in that: The insect larvae include at least one of black soldier flies, maggots, mealworms and cockroaches.

10. The method according to any one of claims 1, 2, 3, 5, and 7, characterized in that: The water content of the concentrated liquid is 70% to 80%.

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