Method for regulating and controlling conversion efficiency of stratiomyiid based on heat storage performance of base material

Abstract

The invention belongs to the field of hermetia illucens breeding, and particularly relates to a method for regulating and controlling the conversion efficiency of hermetia illucens based on the heat storage performance of a base material. According to the method, environmental factors which have obvious influence on heat storage and temperature rise of the base material are researched and determined, and a gadfly converted base material heat storage performance regulation and control model is established. Three base material heat storage performance regulation and control strategies of commercial stratiomyiid larva production, seed pupa production and waste reduction under the optimal conversion efficiency are simulated and explored through various working conditions, the problems that the target efficiency of a stratiomyiid conversion system is low and operation is unstable due to the fact that the base material temperature cannot be regulated and controlled are solved, and a base material temperature regulation and control scheme considering the optimal conversion efficiency is established; annual high efficiency and stability of a hermetia illucens conversion system are ensured, the overall treatment level of organic waste is improved, and the method has an important promoting effect on scientific and efficient breeding of hermetia illucens.

Description

Technical Field

[0001] The invention belongs to the field of black soldier fly breeding, and particularly relates to a method for regulating soldier fly conversion efficiency through heat storage performance of a base material. Background Art

[0002] Using black soldier fly larvae (BSFL) to treat organic waste has many advantages and is considered to be a new technology with huge market prospects, which is increasingly valued. The transformation of waste by black soldier flies is essentially a process of insect-bacteria interaction and metabolism to transform organic matter. Although BSFL has a wide range of adaptability to temperature (15-47°C), the transformation efficiency of this insect-bacteria interaction system is still greatly affected by environmental conditions (especially temperature). Specifically, when the base material temperature is 24-32°C, the insect-bacteria interaction system is most suitable for producing seed pupae; when the base material temperature is lower than 20°C, the base material cannot ferment and produce heat in time, the thermal insulation is poor, the BSFL grows slowly, and the transformation efficiency is extremely low; when the base material temperature is lower than 15°C, the BSFL is in a dormant state and does not grow; when the base material temperature exceeds 35°C, the BSFL cannot complete pupation due to heat stress and is not suitable for seed insect breeding; when the base material temperature is 43-47°C, which is the upper limit of BSFL growth, the fly flies will flee or even die. Therefore, in actual production, certain environmental control strategies need to be adopted to control the stability of the base material temperature during the conversion process in order to maintain better production efficiency.

[0003] Especially in tropical and subtropical high base temperature environments, the biological heat from insect-fungus interactions can easily accumulate in the base material, causing the material temperature to rise to above 35°C, or even greater than 50°C, far exceeding the upper limit of BSFL growth, and due to the lack of specialized scientific research results as support. At present, the environmental control method based on conventional production experience is not only costly, but also difficult to maintain a stable base material temperature, resulting in low conversion efficiency and uncontrollable conversion efficiency, which restricts the scale and industrialization of black soldier fly conversion waste. Therefore, it is urgently needed to systematically study the influencing factors and action rules that cause changes in base material temperature, guide the regulation of the heat storage performance of materials in the conversion bed, achieve heat dissipation and cooling in high temperature weather and heat storage and insulation in low temperature weather, and thus achieve efficient and stable system target conversion efficiency. Summary of the invention

[0004] The present invention provides a method for regulating the conversion efficiency of soldier flies by using the heat storage performance of a base material, establishes a control model, and proposes control strategies under three conversion efficiency targets of producing commercial soldier fly larvae, breeding insect prepupae, and reducing waste. By controlling environmental factors (non-nutritional factors), the base material temperature is maintained at a certain level to avoid thermal and cold stress inhibition of the insect body, thereby ensuring a stable and efficient conversion process.

[0005] The technical solution of the present invention is achieved in this way:

[0006] A regression equation for the maximum temperature of a base material:

[0007] Tmax=187.9636-1.5083×RMC-212.9167×LD+4.0972×H-2.5083×T+1.5×RMC×LD-0.04167×RMC×H+0.0250×RMC×T+2.0000×LD×T

[0008] Among them, T max is the maximum temperature of the base material, in ℃; RMC is the initial relative moisture content of the base material; LD is the initial feed amount of a single worm, in g DM / head; H is the initial thickness of the base material, in cm; T is the ambient temperature of the breeding process, in ℃.

[0009] Furthermore, the T max The value is 25-45.

[0010] A method for regulating soldier fly conversion efficiency by using base material heat storage performance comprises the following steps:

[0011] (1) selecting carbon and nitrogen source raw materials to prepare a culture base that meets the nutritional requirements of soldier fly larvae;

[0012] (2) Counting the initial relative moisture content of the base material, the initial feed amount of a single worm, the initial material thickness and the ambient temperature, and calculating the Tmax value of the base material maximum temperature regression equation according to the above base material maximum temperature regression equation;

[0013] (3) If the value of Tmax is 25-45, it means that the breeding conditions meet the requirements; if T max If the value is not within the range of 25-45, adjust one or more parameters such as the initial relative moisture content of the culture base material, the initial feed amount of single-headed worms, the initial material thickness and the ambient temperature to make T max The value reaches 25-45.

[0014] Furthermore, the calculation method of the initial relative moisture content of the base material is: relative moisture content = water saturation × 100%.

[0015] Further, based on the purpose of producing commercial soldier fly larvae with the best efficiency, the regression equation of the base material worm rate PRL is PRL=-717.8832+13.1731×RMC-40.1083×LD+6.7346×H+7.0297×T-0.0913×RMC×H-0.0913×RMC×H-0.0660×RMC×RMC-0.1237×T×T. At this time, the base material relative moisture content is kept at 99%, the ambient temperature is 28°C, and the material thickness is less than 2 cm. The base material worm rate PRL is the highest, and the highest temperature of the base material during the conversion process is about 37°C; wherein, RMC is the initial relative moisture content of the base material; LD is the initial feed amount of a single worm, in g DM / head; H is the initial material thickness, in cm; T is the ambient temperature, in °C

[0016] Furthermore, based on the purpose of producing the best seed pupae, the weight of 10 worms BW 10 The regression equation is BW10 = -23.18225 + 0.362432 × RMC + 5.56098 × LD + 0.023333 × H + 0.334923 × T - 0.001736 × RMC × RMC - 5.24747 × LD × LD - 0.005896 × T × T. At this time, the initial relative moisture content of the base material is 104%, the ambient temperature is 28 ° C, the initial feed amount of a single worm is 0.5 g DW / head, the initial material thickness is at least 8 cm, and the weight of 10 worms is BW10. 10 The highest temperature of the base material during the conversion process is 29-31℃; RMC is the initial relative moisture content of the base material; LD is the initial feed amount of a single worm, in g DM / head; H is the initial material thickness, in cm; T is the ambient temperature, in ℃

[0017] Furthermore, based on the purpose of optimizing waste reduction efficiency, the regression equation of base material dry matter reduction rate DMTR is:

[0018] DMTR=-427.5891+9.0007×RMC+33.6729×LD+28.0892×H+3.9162×T-0.2440×RMC×H+0.0679×RMC×T-4.7250×LD×H-0.1643×H×T-0.0584×RMC×RMC-71.1562×LD×LD-0.0692×H×H-0.1590×T×T. At this time, the initial relative moisture content of the base material is maintained at 92%, the ambient temperature is 31°C, the initial feed amount is 0.2g DW / head, the initial material thickness is 3.6cm or less, the dry matter reduction rate DMTR is the highest, and the highest temperature of the base material during the conversion process is 39-43°C. Among them, RMC is the relative moisture content of the base material; LD is the feed amount per head worm, in gDM / head; H is the material thickness, in cm; T is the ambient temperature, in °C

[0019] Beneficial effects of the present invention:

[0020] The present invention studies and determines the environmental factors (relative moisture content, insect density, material thickness, and ambient temperature) that have a significant impact on the heat storage and temperature rise of the base material, and establishes a heat storage performance regulation model for the base material for horsefly conversion; through simulations of various working conditions, the heat storage performance regulation strategy of the base material under the three optimal conversion efficiencies of producing commercial soldier fly larvae, breeding insect prepupae, and reducing waste is explored, and the problem of low target efficiency and unstable operation of the horsefly conversion system caused by the inability to control the base material temperature is solved, and a substrate temperature regulation scheme that takes into account the optimal conversion efficiency is established, ensuring the year-round high efficiency and stability of the horsefly conversion system, which is beneficial to improving the overall treatment level of organic waste and plays an important role in promoting the scientific and efficient breeding of black soldier flies. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, 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 invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0022] Figure 1 The effect of the initial pH of the base material on the relative insect production rate.

[0023] Figure 2 This is the effect of the initial thickness of the base material on the relative insect production rate.

[0024] Figure 3 The effect of ambient temperature on relative larvae production rate.

[0025] Figure 4 This is the effect of the initial feeding amount of a single larva on the relative larvae production rate.

[0026] Figure 5 This is the effect of the initial moisture content of the base material on the relative insect production rate.

[0027] Figure 6 It is the correlation between the thermal storage and heating effect of the base material and the conversion efficiency characterization index.

[0028] Figure 7 This is a single factor sensitivity analysis of the maximum temperature of the base material.

[0029] Figure 8 Contour diagram and response surface diagram of the effect of AB on the maximum temperature of the base material.

[0030] Fig. 9 It is the level of environmental factors based on the optimal insect production under the experimental conditions. The value of PRL in the figure is the maximum value under the experimental conditions; the circle represents the optimal value of this variable under the model simulation.

[0031] Fig.10 It is the level of environmental factors based on the optimal insect production under the experimental condition expansion condition 1. The value of PRL in the figure is the maximum value under the experimental conditions; the circle represents the optimal value of this variable under the model simulation.

[0032] Fig.11 It is the level of environmental factors based on the optimal insect production under the experimental condition extension condition 2. The value of PRL in the figure is the maximum value under the experimental conditions; the circle represents the optimal value of this variable under the model simulation.

[0033] Fig.12 It is the level of environmental factors based on the optimal insect individual under the experimental conditions. The value of BW10 in the figure is the maximum value under the experimental conditions; the circle represents the optimal value of this variable under the model simulation. Fig.13 It is the level of environmental factors based on the optimal insect individual under the experimental condition expansion condition 1. The value of BW10 in the figure is the maximum value under the experimental conditions; the circle represents the optimal value of this variable under the model simulation.

[0034] Fig.14 The environmental factor level based on the optimal insect individual for the experimental condition extension 2. The value of BW10 in the figure is the maximum value under the experimental conditions; the circle represents the optimal value of this variable under the model simulation.

[0035] Fig.15 It is the level of environmental factors based on optimal raw material reduction under test conditions. The value of BW10 in the figure is the maximum value under test conditions; the circle represents the optimal value of this variable under model simulation. Fig.16Environmental factor levels based on optimal raw material reduction under test condition extension condition 1. The value of BW10 in the figure is the maximum value under test conditions; the circle represents the optimal value of this variable under model simulation.

[0036] Fig.17 The environmental factor level based on the optimal raw material reduction under the experimental condition expansion condition 2. The value of BW10 in the figure is the maximum value under the experimental conditions; the circle represents the optimal value of this variable under the model simulation. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Example 1

[0039] Study on the influencing factors and regulation model of heat storage performance of gadfly-transformed base materials

[0040] The test of the effect of single environmental factors on insect production performance was carried out to screen the types and levels of environmental factors (non-nutritional factors) used to study the heat storage performance regulation model of the base material. The nutritional composition of the experimental base material adopts the formula of Geiss feed, that is, 50% wheat bran, 30% soybean meal, and 20% corn flour. The initial control conditions of each single factor experimental base material are as follows:

[0041] (1) Initial pH value of feed: absolute moisture content 70%, feed thickness 6 cm, inoculation amount 0.3 g dry basis / head, breeding process ambient temperature 30°C, pH according to test conditions.

[0042] (2) Initial thickness of feed (H): absolute moisture content 70%, pH 7.2, inoculation amount 0.3 g dry basis / head, ambient temperature during culture process 30°C, feed thickness according to test conditions.

[0043] (3) Ambient temperature (T): absolute moisture content 70%, pH 7.2, inoculation amount 0.3 g dry basis / head, feed thickness 6 cm, and the ambient temperature during the breeding process according to the experimental conditions.

[0044] (4) LD: absolute moisture content 70%, pH 7.2, material thickness 6 cm, ambient temperature during the culture process 30°C, and LD according to the test conditions.

[0045] (5) Moisture content (MC): pH 7.2, insect inoculation amount 0.3 g dry basis / head, material thickness 6 cm, ambient temperature during culture process 30 °C, moisture content according to test conditions.

[0046] Relative larvae production rate (%) = the actual larvae production rate under a certain level of the single factor test / the maximum larvae production rate under different levels of the single factor test * 100%

[0047] 1.1 Screening of environmental factors and determination of their levels

[0048] (1) Initial pH value of base material

[0049] like Figure 1 As shown in the figure, within the pH range of 3 to 11, the relative insect production rate is close to 100%, the coefficient of variation (CV) is 1.9%, and the discrete degree is small. The initial pH of the base material is 3 to 11, which covers most materials, but has no significant effect on the relative insect production rate of black soldier fly larvae (BSFL), indicating that as long as the pH environment is not extreme, it can meet the requirements of efficient insect production, and the pH of the initial material is not used as an investigation factor for further experiments.

[0050] (2) Initial thickness of base material (H)

[0051] like Figure 2 As shown in the figure, if the initial material is too thin, the water retention is poor and the growth of BSFL is inhibited; if the material is too thick, it is difficult to feed deeply and it is easy to accumulate heat and increase the temperature, which affects the conversion effect. Among them, the relative insect production rate is not significantly different when the initial thickness of the material is 4cm and 6cm, but it is significantly higher than other thicknesses. H (initial thickness of the material) is listed as the investigation factor for further experiments, and the factor level is 2, 5, and 8cm.

[0052] (3) Ambient temperature (T)

[0053] like Figure 3 As shown in the figure, the relative larval rate of BSFL is the highest at an ambient temperature of 30°C, which is significantly higher than other temperature levels. This is consistent with the existing reported results that "within the range of 24-32°C, the development parameters of the larval stage of the bright-spotted flat-horned soldier fly can reach the optimal level at 28°C, while lowering and raising the temperature will lead to a longer development period, reduced biomass accumulation and lower survival rate." T (ambient temperature) was listed as the investigation factor for further experiments, and the factor levels were 25, 30, and 35°C.

[0054] (4) Food intake per larva (LD)

[0055] like Figure 4 As shown in the figure, insect density reflects the aggregation effect of insects and the degree of individual utilization of nutrients. The insect density is characterized by the dry matter feeding amount of each larva. As shown in the figure, under the feeding amount gradient of 0.2g dry basis / head, the relative insect production rate of BSFL decreases significantly with the increase of feeding amount. According to the investigation, the feeding amount level for test and production is 0.3-0.4g dry basis / head. Therefore, D (feeding amount of a single larva) is listed as the investigation factor for further experiments, and the factor level is 0.1, 0.3, and 0.5g dry basis / head.

[0056] (5) Moisture content (MC)

[0057] The role of water is to dissolve nutrients and oxygen to ensure the oxygen and nutrient needs of BSFL. Figure 5 As shown in the figure, the initial moisture content of the feed has a significant effect on the insect production rate. The relative insect production rate first increases and then decreases with the increase of the absolute moisture content in the feed ( Figure 5 The decimals on the upper column represent the water saturation of the material, and the percentages on the lower column represent the absolute moisture content), which can be selected as factors for further testing. Compared with the previous indicators that use absolute moisture content (AMC) to characterize the moisture state of the material, relative moisture content (RMC) (relative moisture content = water saturation × 100% = actual absolute mass moisture content of the material / absolute mass moisture content of the material under water absorption saturation × 100%) combines the two aspects of air permeability and dissolved nutrition, and can overcome the influence of material properties.

[0058] like Figure 5 The figure below shows that at water saturation of 0.95 and 1.00, the relative insect production rate was the highest, 97.4% and 99.9% respectively, with no significant difference (P<0.05), which was significantly higher than the production rate under adjacent water conditions, when the corresponding absolute water content was 78% and 82%. The RMC levels in further experiments were 85%, 95%, and 105%.

[0059] Based on the analysis of the test results of the influence of the above-mentioned single environmental factors on insect production performance, the factors used to study the thermal storage performance of the substrate were determined to be relative moisture content RMC, insect density LD, material thickness H, and ambient temperature T. The factor selection levels used for the Box-Behnken design response surface methodology to study the regulation model are shown in Table 3.

[0060] Table 3 Experimental factor levels and values

[0061] Environmental factors unit Factor Code Code-1 Level Code +1 Level Relative moisture content RMC ％ A 85 105 Insect density LD gDM / header B 0.1 0.5 Material thickness H cm C 2 8 Culture temperature T ℃ D 25 35

[0062] 1.2 Study on the influencing factors and regulation model of heat storage performance of horsefly-transformed base materials

[0063] Based on the above four environmental factors, a Box-Behnken response surface experimental design study was conducted to analyze the correlation between the heat storage and temperature rise effect of the base material and the conversion efficiency index. The index that characterizes the heat storage performance of the base material is clearly defined as the "maximum temperature of the base material". A control model was established, and control strategies based on the production of commercial soldier fly larvae, seed insect prepupae, and waste reduction were proposed. The experimental design is shown in Table 4.

[0064] Table 4 Box-Behnken test design and factor values

[0065]

[0066]

[0067] 1.2.1 Correlation between base material heat storage and heating effect and conversion efficiency index

[0068] The correlation between the base material heat storage and temperature rise effect and the conversion efficiency index is as follows: Figure 6 As shown (using origin software to draw and analyze), the maximum temperature of the base material during the test (the original temperature was measured and counted every day) was significantly positively correlated with the average temperature (the original temperature was measured and calculated every day), the cumulative temperature (the original temperature was measured and calculated), and the dry matter reduction rate (measured / calculated), and was significantly negatively correlated with the weight of every 10 insects and the insect body conversion rate; while the insect body conversion rate was significantly negatively correlated with the base material insect production rate, and the maximum temperature of the base material affected the base material insect production rate by affecting the insect body conversion rate. This shows that the base material temperature has an important influence on the conversion efficiency, and the conversion efficiency of soldier flies can be regulated by regulating the maximum temperature of the base material during the conversion process.

[0069] 1.2.2 Base material heat storage and temperature rise control model

[0070] Taking the maximum temperature of the base material (Tmax) as the response value, the Analysis module in Design-Expert 12 software was used to determine the optimal fitting model based on the quadratic polynomial regression equation and combined with the model fitting analysis and variance analysis results. The single factor sensitivity curve and contour map results were combined to analyze the influence of single factors and their interactions, and a base material heat storage and temperature rise control strategy was proposed. The variance analysis results of the test data are shown in Table 5:

[0071] Table 5 Maximum temperature of base material (T max ) Response surface model ANOVA

[0072]

[0073] Note: ** indicates extremely significant difference (P<0.01); * indicates significant difference (P<0.05).

[0074] The variance analysis of the response surface test of the maximum temperature (Tmax) of the base material showed that the model P < 0.001, which was extremely significant, and the lack of fit term P = 0.2484 > 0.05, which was not significant, indicating that the model had a good fit; the model determination coefficient R 2 =0.8706, Corrected determination coefficient R Adj 2 =0.8188, both are not less than 0.8, and R Pre 2 and R Adj 2The difference between the two is 0.1292, which is less than 0.2. The two are close, indicating that the model can well reflect the test data, the regression equation has a good fit, and the test error obtained is small. CV (%) = 5.06, less than 10%, the coefficient of variation is small, indicating that the test error is small. Signal-to-noise ratio = 17.61> 4, indicating that the model design is reasonable and can be used for result prediction.

[0075] Under the condition of significant level (p<0.05), the linear terms relative moisture content A (p<0.0001), single larvae feeding amount B (p=0.0013), ambient temperature D (p=0.0005), and the interaction term AB (p=0.0057) in the regression model of the maximum temperature of the base material Tmax were all significant, reaching the extremely significant level, while the other terms were not significant.

[0076] From the analysis of Table 5, the coding data model based on each environmental factor variable is obtained: Tmax = 38.24-5.17×A-2.08×B+0.42×C+2.33×D+3×A×B-1.25×A×C+0.25×A×D+2×B×D......(regression equation 1),

[0077] The model converted into the actual data of each environmental factor variable is: Tmax = 187.9636-1.5083×RMC-212.9167×LD+4.0972×H-2.5083×T+1.5×RMC×LD-0.04167×RMC×H+0.0250×RMC×T+2.0000×LD×T.....(Regression Equation 2)

[0078] In the regression equation (1), Tmax is the maximum temperature of the base material, °C; A, B, C, and D are the statistical codes of the environmental factor variables relative moisture content RMC (%), single worm feeding amount LD (g DM / head), material thickness H (cm), and culture temperature T (°C), respectively.

[0079] According to the Box-Behnken experimental design principle, the factor coding data model can be used to predict the response based on the given level of each factor, with the high level of the factor coded as +1 and the low level coded as -1. The coding model can identify the relative impact of each factor by comparing the factor coefficients; while the model based on the actual data of the factors can be used to predict the response of each factor at a given level. The level of each factor should be specified in the original unit. Since the coefficients in this model are scaled according to the units of each factor, the intercept is not in the center of the design space and cannot be used to determine the relative impact of each factor.

[0080] 1.2.3 Analysis of Factor Influence Effect

[0081] The influence of the four factors A, B, C and D on the maximum temperature of the base material is significant and the influence degree is different. The order of influence is: A**>D**>B**>C. A, B and D all reach extremely significant levels, and C is not significant. According to the data model based on the coding of each environmental factor variable (regression equation 1): Tmax=38.24-5.17×A-2.08×B+0.42×C+2.33×D+3×A×B-1.25×A×C+0.25×A×D+2×B×D), the coefficient of the first-order term D is positive, and the coefficients of the first-order terms A and B are negative, indicating that the influencing factor D is positively correlated with Tmax, and the influencing factors A and B are negatively correlated with Tmax. This is consistent with the results of the single-factor sensitivity analysis of the maximum temperature of the base material.

[0082] Based on the quadratic regression model (coded data model) of the maximum temperature of the base material, the response surface diagram and contour diagram of the interaction terms AB with significant interaction effects on Tmax are drawn, such as Figure 7-8 shown.

[0083] As the initial relative moisture content of the substrate and the level of single-headed worm feeding increased, Tmax decreased, indicating that reducing the insect density in the conversion bed, increasing the relative moisture content of the substrate, and reducing the maximum temperature of the substrate can alleviate the heat stress of the insect body. Studies have shown that 43-47℃ is the upper limit of the growth of black soldier fly larvae (Tmax). For this reason, the thermal storage and heating performance of the substrate should be controlled by adjusting the relative moisture content of the substrate first, and then the thermal storage and heating performance of the bioconversion bed can be controlled by considering the facility regulation to maintain the ambient temperature and the initial worm inoculation amount of the substrate.

[0084] 1.2.4 Multi-objective control strategy for base material thermal storage performance

[0085] Aiming at the three production goals of black soldier fly bioconversion (producing commercial soldier fly larvae, producing seed worm prepupae and reducing waste), the base material worm production rate (PRL), 10 worm weight (BW10), and dry matter reduction rate (DMTR) were used as response values ​​to establish mathematical models between environmental factors A (relative moisture content value RMC), B (single worm feeding value LD), C (material thickness value H), and D (ambient temperature value T) and response indicators. The results are shown in Tables 6 and 7. Furthermore, combined with actual production conditions, the range of environmental factor levels was expanded, and the Optimization module in Design-Expert 12 software was used to analyze the stability of each environmental factor level under different conditions to achieve the optimal conversion efficiency, and to explore the base material heat storage performance control strategy under the optimal conversion efficiency.

[0086] Table 6 Model construction

[0087]

[0088] Note: PRL (%) of base material worm production rate = BSFL dry weight obtained after the experiment / initial base material dry weight * 100%; BW10 is the weight of every 10 worms; DMTR (%) = (initial base material dry weight - base material dry weight at the end of the experiment) / initial base material dry weight * 100%.

[0089] Table 7 Evaluation indicators of each model

[0090]

[0091] Note: ** indicates extremely significant difference (P<0.01); * indicates significant difference (P<0.05).

[0092] (1) Control of heat storage performance of substrate based on the optimal production efficiency of commercial soldier fly larvae

[0093] The environmental factor levels for optimal insect production under different conditions are shown in Figure 9-11 The variation of environmental factors and conversion efficiency levels under different working conditions is shown in Table 9. Among them, the experimental conditions are the general production conditions, that is, the range of environmental factor values ​​used in this experiment; condition expansion conditions 1 and condition expansion conditions 2 are the range of environmental factor values ​​under two extreme conditions that can be achieved in actual production; the conventional group is the normal breeding condition, and no environmental factor regulation is performed; the optimal group 1 to the optimal group 4 are the four working condition treatment groups obtained after the optimal analysis according to the base material insect production rate mathematical model and the Tmax model.

[0094] The results of the model analysis in Table 9-1 show that the optimal insect production level under different working conditions is 31% to 37%, and the coefficient of variation is 7.47%, which is greater than 5%, and is affected by environmental factors to a certain extent. The coefficients of variation of relative moisture content, ambient temperature, and maximum material temperature are less than 0.5%, and the coefficients of variation of material thickness and the initial feeding amount of single-headed worms are 53.45% and 69.03% (highly variable), respectively. The optimal insect production rate increases with the decrease of the initial single-headed worm feeding amount and the decrease of material thickness. Therefore, under the optimal insect production rate, the relative moisture content, ambient temperature, and maximum material temperature are relatively stable, and the maximum temperature is within the normal growth range of BSFL; the material thickness and the initial feeding amount of single-headed worms have a greater impact on insect production, and the optimal insect production rate increases with the decrease of the initial single-headed worm feeding amount and the decrease of material thickness, which is a factor that needs to be regulated.

[0095] It is then concluded that the method for controlling the heat storage performance of the base material based on the optimal efficiency of producing commercial soldier fly larvae is: by maintaining the initial relative moisture content of the base material (about 99%) and the ambient temperature (28°C) during the breeding process, combined with appropriately increasing the initial insect density (the high value under each working condition) and reducing the initial material thickness (below 2 cm, the low value under each working condition), the optimal insect production can be guaranteed. As shown in Table 9-2, after actual breeding tests, the PRL values ​​were statistically analyzed, and there was no significant difference between the PRL values ​​calculated by the PRL mathematical model formula, and by regulating environmental factors, the PRL values ​​of each treatment can be significantly higher than those of conventional breeding methods. It shows that the PRL mathematical model and Tmax model obtained by the present invention can not only accurately predict the PRL value, but also significantly improve the base material insect production rate of black soldier flies.

[0096] Table 9-1 Analysis of factors and conversion efficiency under different working conditions

[0097] Working conditions RMC LD H T Tmax PRL unit ％ gDM / header cm ℃ ℃ ％ Test conditions 98.4 0.10 2.0 28.4 37.3 31.1 Condition expansion condition 1 99.1 0.05 1.0 28.4 37.2 34.8 Condition expansion condition 2 99.4 0.01 0.5 28.4 37.3 37.4 A 98.9 0.05 1.2 28.4 37.3 34.5 SD 0.4 0.04 0.6 0.0 0.0 2.6 CV / % 0.4 69.03 53.5 0.0 0.1 7.5

[0098] Table 9-2 Test results under different optimized conditions

[0099] Working conditions RMC LD H T Tmax PRL simulation value Farming Statistics PRL unit ％ gDM / header cm ℃ ℃ ％ ％ conventional 87.5 0.10 8.0 29.0 48.0 18.5 18.48 Best 1 99.0 0.10 2.0 28.0 36.8 31.4 31.03 Best 2 99.0 0.05 1.0 28.0 37.3 35.1 35.45 Best 3 99.0 0.01 0.5 28.0 37.6 37.7 37.64 Best 4 99.0 0.05 1.2 28.0 37.3 34.8 34.72

[0100] (2) Control of heat storage performance of base material based on optimal production efficiency of seed pupae

[0101] The environmental factor levels at the optimal insect weight under different working conditions are shown in Figure 12-14 The variation of environmental factors and conversion efficiency levels under different working conditions is shown in Table 10-1. Among them, the experimental conditions are the general production conditions, that is, the range of environmental factor values ​​used in this experiment; condition expansion conditions 1 and condition expansion conditions 2 are the range of environmental factor values ​​under two extreme conditions that can be achieved in actual production; the conventional group is the normal breeding condition, and no environmental factor regulation is performed; the optimal group 1 to the optimal group 4 are the four working condition treatment groups obtained after the optimal analysis according to the BW10 mathematical model and the Tmax model.

[0102] The results of the model analysis in Table 10-1 show that the average level of the best individual worms under different working conditions is 2.2g / 10 heads, with a coefficient of variation of 3.95% (small variation), and is less affected by the level of environmental factors. Among the environmental factors, the coefficient of variation of the material thickness is the largest, at 32.78% (medium variation); the coefficients of variation of the relative moisture content, the initial feed amount of a single worm, and the ambient temperature are less than 5% (small variation). To this end, by maintaining the relative moisture content (104%), ambient temperature (28°C) and the initial feed amount of a single worm (0.5gDW / head) levels, maintaining a relatively high initial material thickness (at least 8cm, the highest value under each working condition), it is possible to ensure that better individual seed pupae are obtained. This is also a method for regulating the heat storage performance of the base material based on the optimal efficiency of producing seed pupae.

[0103] As shown in Table 10-2, after actual breeding experiments, the BW10 values ​​were statistically analyzed, and there was no significant difference between the BW10 values ​​calculated by the BW10 mathematical model formula, and the BW10 value of the treatment group regulated by environmental factors was significantly higher than that of the conventional breeding method. This shows that the BW10 mathematical model and Tmax model obtained by the present invention can not only accurately predict the BW10 value, but also significantly increase the weight of 10 black soldier flies, and significantly improve the efficiency of producing seed pupae.

[0104] Table 10-1 Analysis of factors and conversion efficiency under different working conditions

[0105] parameter RMC LD H T Tmax BW10 unit ％ gDM / header cm ℃ ℃ g / 10 heads Test conditions 104.4 0.50 8.0 28.4 31.6 2.1 Condition expansion condition 1 104.4 0.53 10.0 28.4 31.1 2.2 Condition expansion condition 2 104.4 0.53 15.0 28.4 29.9 2.3 A 104.4 0.52 11.0 28.4 30.9 2.2 SD 0.0 0.02 3.6 0.0 0.9 0.1 CV / % 0.0 3.33 32.8 0.0 2.9 4.0

[0106] Table 10-2 Test results under different optimized conditions

[0107]

[0108]

[0109] (3) Control of base material heat storage performance based on optimal waste reduction efficiency

[0110] The environmental factor levels for optimal raw material reduction under different working conditions are shown above. Figure 15-17 The variation of environmental factors and conversion efficiency levels under different working conditions is shown in Table 11-1. Among them, the experimental conditions are the general production conditions, that is, the range of environmental factor values ​​used in this experiment; condition expansion conditions 1 and condition expansion conditions 2 are the range of environmental factor values ​​under two extreme conditions that can be achieved in actual production; the conventional group is the normal breeding condition, and no environmental factor regulation is performed; the optimal group 1 to the optimal group 4 are the four working condition treatment groups obtained after the optimal analysis according to the DMTR mathematical model and the Tmax model.

[0111] As shown in Table 11-2, the optimal raw material reduction level under different working conditions is 71.7%, with a coefficient of variation of 0.58% (small variation), and is less affected by the level of environmental factors. The average level of material thickness is 1.71cm, but it is highly variable, with a coefficient of variation of 80.17%; the average levels of relative moisture content, initial feed amount of single head worm, ambient temperature, and maximum material temperature are 92.37%, 0.2g DM / head, 31.12℃, and 40.72℃, respectively, with a coefficient of variation of less than 15% (small variation). To this end, by maintaining the relative moisture content (92%), ambient temperature (31℃), and initial feed amount of single head worm (0.2g DW / head) levels, combined with appropriately reducing the initial material thickness (3.6cm and below), the waste reduction efficiency can be improved and the operating efficiency can be improved. This is also a method for regulating the thermal storage performance of base materials based on the optimal waste reduction efficiency.

[0112] After actual breeding tests, the DMTR values ​​were statistically analyzed, and there was no significant difference between the DMTR values ​​calculated by the DMTR mathematical model formula, and the DMTR values ​​of the treatment group regulated by environmental factors were significantly higher than those of conventional breeding methods. This shows that the combination of the DMTR mathematical model obtained by the present invention and the Tmax model can not only accurately predict the DMTR value, but also guide the soldier fly conversion system to reduce waste efficiently and stably. This also shows that the current conventional working conditions are conducive to waste reduction.

[0113] Table 11-1 Analysis of the variation of environmental factors and conversion efficiency levels under different working conditions

[0114] parameter RMC LD H T Tmax DMTR unit ％ gDM / header cm ℃ ℃ ％ Test conditions 89.0 0.18 3.6 29.3 43.0 71.3 Condition expansion condition 1 93.4 0.20 1.0 31.7 39.9 71.7 Condition expansion condition 2 94.7 0.22 0.5 32.3 39.3 72.3 A 92.4 0.20 1.7 31.1 40.7 71.7 SD 2.4 0.02 1.4 1.3 1.6 0.4 CV / % 2.6 8.16 80.2 4.1 4.0 0.6

[0115] Table 11-2 Test results under different optimized conditions

[0116] parameter RMC LD H T Tmax DMTR analog value DMTR breeding statistics unit ％ gDM / header cm ℃ ℃ ％ ％ conventional 87.5 0.20 5.0 29.0 44.2 72.3 72.29 Best 1 92.4 0.18 3.6 31.0 41.1 70.0 70.02 Best 2 92.4 0.20 1.0 31.0 40.2 71.9 71.77 Best 3 92.4 0.22 0.5 31.0 39.9 72.2 72.55 Best 4 92.4 0.20 1.7 31.0 40.4 71.4 71.28

[0117] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A maximum temperature regression equation for a base material, characterized in that: The regression equation is: Tmax=187.9636-1.5083×RMC-212.9167×LD+4.0972×H-2.5083×T+1.5×RMC×LD-0.04167×RMC×H+0.0250×RMC×T+2.0000×LD×T;where, T max is the maximum temperature of the base material, in ℃; RMC is the relative moisture content of the base material, in %; LD is the feed amount per worm, in g DM / head; H is the material thickness, in cm; T is the ambient temperature, in ℃.

2. A base material maximum temperature regression equation as claimed in claim 1, characterized in that: The T max The value is 25-45.

3. A method for regulating the conversion efficiency of soldier flies by using the heat storage performance of a base material, characterized in that: The following steps are involved: (1) selecting carbon and nitrogen source raw materials to prepare a culture base that meets the nutritional requirements of soldier fly larvae; (2) Counting the relative moisture content of the base material, the amount of feed per worm, the thickness of the base material and the culture temperature, and calculating the Tmax value of the base material maximum temperature regression equation according to the base material maximum temperature regression equation of claim 1 or 2; (3) If the value of Tmax is 25-45, it means that the breeding conditions meet the requirements; if T max If the value is not within the range of 25-45, adjust one or more parameters such as the relative moisture content of the culture substrate, the amount of feed per worm, the thickness of the substrate and the culture temperature to make T max The value reaches 25-45.

4. The method according to claim 3, characterized in that The relative moisture content of the base material is calculated as follows: relative moisture content = water saturation × 100%.

5. The method according to claim 3, characterized in that Based on the purpose of producing commercial soldier fly larvae with optimal efficiency, the regression equation of the base material larvae production rate PRL is PRL=-717.8832+13.1731×RMC-40.1083×LD+6.7346×H+7.0297×T-0.0913×RMC×H-0.0913×RMC×H-0.0660×RMC×RMC-0.1237×T×T, among which, RMC is the relative moisture content of the base material; LD is the feed amount per single worm, in g DM / head; H is the material thickness, in cm; T is the ambient temperature, in ℃.

6. The method according to claim 5, characterized in that The initial relative moisture content of the base material is 99%, the ambient temperature during the breeding process is 28°C, the initial thickness of the base material is less than 2cm, the insect production rate PRL of the base material is the highest, and the highest temperature of the base material during the conversion process is about 37°C.

7. The method according to claim 3, characterized in that Based on the purpose of producing the best seed pupae, the weight of 10 worms BW 10 The regression equation is BW10 = -23.18225 + 0.362432×RMC+5.56098×LD+0.023333×H+0.334923 ×T-0.001736×RMC×RMC-5.24747×LD×LD-0.005896×T×T, where RMC is the relative moisture content of the base material; LD is the feed amount per single worm, in g DM / head; H is the material thickness, in cm; T is the ambient temperature, in ℃.

8. The method according to claim 7, characterized in that The initial relative moisture content of the base material is 104%, the ambient temperature during the breeding process is 28°C, the initial feed amount of a single worm is 0.5g DW / head, the initial thickness of the base material is at least 8cm, and the weight of 10 worms is BW 10 The highest temperature of the base material during the conversion process is 29-31°C.

9. The method according to claim 3, characterized in that Based on the purpose of optimizing waste reduction efficiency, the regression equation of base material dry matter reduction rate DMTR is DMTR=-427.5891+9.0007×RMC+33.6729×LD+28.0892×H+3.9162×T-0.2440×RMC×H+0.0679×RMC×T-4.7250×LD×H-0.1643×H×T-0.0584×RMC×RMC-71.1562×LD×LD-0.0692×H×H-0.1590×T×T, where RMC is the relative moisture content of the base material; LD is the single head worm feeding amount, in g DM / head; H is the material thickness, in cm; T is the ambient temperature, in ℃.

10. The method according to claim 9, characterized in that The initial relative moisture content of the base material is 92%, the ambient temperature during the breeding process is 31°C, the initial feed amount is 0.2g DW / head, the initial thickness of the base material is 3.6cm or less, the dry matter reduction rate DMTR is the highest, and the highest temperature of the base material during the conversion process is 39-43°C.

Images