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[Objective] To study the nutrient laws of Hermetia illucens transformation treatment of kitchen waste. [Method]Using Hermetia illucens and kitchen waste as research objects, Hermetia illucens were used to convert kitchen waste at normal temperature (S1, S2, S3) and high temperature constant temperature (S1, S2, S3), and the reduction rate, conversion rate, insect protein, fat and other parameters of kitchen waste were measured. [Result] Hermetia illucens significantly increases the conversion rate of kitchen waste at temperatures ranging from 30 to 33℃ compared to normal temperature. S1, S2 and S3 increased the conversion rate by 9. 26%, 10. 73% and 19. 63% compared to C1, C2 and C3, respectively. The S3 group with 7. 2 kg added had the highest conversion rate, and a feed to insect ratio of 2. 68 to 3. 20 ∶ 1 showed its observable economic benefits. Hermetia illucens could convert 24. 46% of low protein and 21. 24% of low fat kitchen waste into high-quality feed and biodiesel raw materials with high protein and fat content of up to 43. 12% and 28. 58% in 21 days. 58. 32% - 62. 74% of protein and 60. 14%-63. 47% of fat in kitchen waste were ultimately converted into the protein and fat of the insect itself. [Conclusion]This utilization method of converting kitchen waste through Hermetia illucens will have great potential in the future. [ABSTRACT FROM AUTHOR]

To evaluate the dietary value of different sources of black soldier fly larvae（BSFL）for red tilapia (O. mossambicus×O. niloticus), the meal of BSFL reared on pineapple residue (PR), wheat bran (WB), and kitchen waste (KW) was used to replace fish meal in the basal diet at a ratio of 4%, and the commercial xanthophyll was supplemented into the basal diet formulate five iso-nitrogenous and iso-energetic diets. They were fed to red tilapia fry [initial weight (0.35±0.01) g] for 9 weeks, then the skin color changes of fish were recorded, the growth performance, physical indicators, and tissue carotenoid concentration were measured. A cold stress trial was conducted with the water temperature reducing from 26 ℃ to 10 ℃ within 8 hours, and the mortality rate of the fish was calculated. The results showed that, the value of the weight gain rate of the fry from high to low was:the WB-BSFL group, PR-BSFL group, the control group, the Xanthophyll group, and the KW-BSFL group. Among them, the weight gain rate of theWB-BSFL group was significantly higher than that of the KW-BSFL group, while the hepatosomatic index and the viscerosomatic index were significantly lower than those of the WB-BSFL groupand PR-BSFL group (P<0.05). The highest yellowness (b*) of the fish head and dorsum was observed in the PR-BSFL group, while that of the abdomen was found in the Xanthophyll group. The total concentration of carotenoid in the scales, skin, and dorsal fin reached the highest levels in the PR-BSFL group, WB-BSFL group, and Xanthophyll group, respectively, which were all significantly higher than that of the control and KW-BSFL groups (P<0.05). After the cold stress, the survival rates of the WB-BSFL and the PR-BSFL groups were 92.5% and 85.0%, higher than that of the control group (76.7%), and significantly higher than those of the KW- BSFL group (69.2%) and the Xanthophyll group (72.5%) (P<0.05). In conclusion, this study indicates that the meal of BSFL reared on pineapple residue and wheat bran can improve the growth performance and physical indicators of red tilapia fry, and promote its cold resistance ability by partially substituting dietary fish meal. Furthermore, the meal of BSFL reared on pineapple residue improves the skin color of fish effectively by increasing the accumulation of carotenoid in tissues, with close effects to the supplementation of commercial xanthophyll. [ABSTRACT FROM AUTHOR]

Aerobic composting is one of the primary steps for the resource utilization and harmless treatment of rural kitchen waste. The treatment device of food waste is ever increasingly needed for single or multiple households, as the development of separate waste collection and promotion of on-the-spot organic waste disposal and utilization. In this study, an aerobic composting device was designed to consider segmented fermentation for composting material, precise aeration and turning control, and multi-function integration. According to the four-stage aerobic composting, four chambers of sequential fermentation were utilized to achieve the separate fermentation of materials in different stages for the harmless treatment of the product. This integrated system also incorporated the agitation apparatus, aeration equipment, control devices, leachate collection mechanisms, and odor control systems. Continuous feeding was employed to introduce the kitchen waste and sawdust daily at a wet-to-weight 10:3. The aeration strategy was set at one minute of aeration every 10 min, and an aeration rate of 10L/min. The stirring frequency was positive for 4 min, reverse for 6 min, and stop for 240 min. The mixing performance simulation and composting experiment were conducted using kitchen waste and pine sawdust as the feedstock. In the simulation test: a fermentation tank and material particle model were constructed and calibrated the simulation parameters of kitchen waste and pine sawdust. The mixing state was simulated to explore the effect of kitchen waste and pine sawdust in four fermentation tanks using the discrete element simulation software EDEM. The mixing degree was calculated for the two kinds of materials in the fermentation tank using the coefficient of variation. The working performance of the equipment was verified in the test. In the composting experiment, solid samples were collected on days 21, 23, and 25 of the composting process, termed as the feeding port (P1), discharge port (P6), and the mid-sections of the first to fourth fermentation tanks (P2 to P5). Physical and chemical properties were determined for the maturity indices of the fermented products. The gas samples were analyzed using portable gas detectors to measure the concentrations of ammonia (NH3) and hydrogen sulfide (H2S) within the first, second, third, and fourth fermentation chambers, as well as at the outlet of the deodorization unit (P7). The results show that the mixing uniformity of materials in the fermentation bin was about 94%, which fully met the requirement that the mixing degree of fermentation materials reached 90%. Furthermore, the color of the fermented material was gradually darkened, the unpleasant odor gradually dissipated, and the fermented material was loose and granular after aerobic fermentation. The compost experienced a high-temperature phase exceeding 55°C for over 5 d, and following 20 d of continuous fermentation. The number of fecal coliforms reached the hygienic safety standard. And egg mortality rate reached 100% for Ascaris lumbricoides. The seed germination index was 73%, fully meeting the requirements of the National Standard for Organic Fertilizer (NY/T 525-2021). In summary, continuous composting and independent fermentation control can be expected to effectively enhance the quality of the fermentation product in different stages. This research can also provide technical references for local resource utilization, fertilizer application, and harmless disposal of kitchen waste in rural regions. [ABSTRACT FROM AUTHOR]

Kitchen waste is composed of complex and diverse ingredients with a variety of organic matter and inorganic salts, which is perishable and foul-smelling under high temperature conditions in summer. To reduce the deterioration rate of kitchen waste in the collection and storage process and cool down the kitchen waste in community residences for short time before treatment, the intelligent temperature- controlled dustbin was designed based on the fan-pad cooling device. Several temperature sensors were distributed inside the dustbin and controlled by Siemens PLC. The execution conditions of the fan-pad cooling device were programmed, and the PID algorithm was used for software optimization, while the data was visualized by touch screen. The intelligent control of the fan-pad cooling system was realized to maintain the internal temperature of the dustbin in the set range, and the system debugging and test verification were conducted. The results show that the detection error of the intelligent temperature control system is less than 0.5 °C, which meets the accuracy requirements. When the outdoor temperature is as high as 35 °C, the average temperature in the dustbin can be maintained at about 25 °C, which meets the constant temperature storage requirements of kitchen waste. [ABSTRACT FROM AUTHOR]

Amino acid fermentation liquid was prepared from waste feathers by microbial fermentation, and the influence of composting of kitchen waste was investigated. The results showed that the addition of amino acid fermentation liquid could improve the decomposition process and weight reduction effect of kitchen waste compost, and could effectively increase the content of alkali-hydrolytic nitrogen and available phosphorus in compost, and improved the activity of microorganisms, among which the activities of protease, amylase, cellulase and lipase increased by 21.29%, 36.42%, 43.83% and 11.16%, respectively. The addition of amino acid fermentation broth increased the complexity of bacterial community interaction and changed the structure of bacterial community, and the relative abundance of Bacillus and Klebsiella increased. GI, mass digestion rate, HA and amylase were positively correlated with colony structure, while HS, cellulase and available phosphorus were negatively correlated with colony structure. The study provides a new idea for using waste protein resources to cooperate with aerobic composting of kitchen waste in the future. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Bioprocess Engineering is the property of Chinese Journal of Bioprocess Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The medium temperature amylase, glucose oxidase and p-gluconase, which were added to the pile at a ratio of 60 mg/kg・ To investigate their effects and potential mechanisms on the composting cycle, nitrogen fixation effect, and organic matter degradation during the aerobic composting process・ The results showed that although the addition of three exogenous enzymes did not enhance the peak performance during the high temperature period during the composting process, medium temperature amylase and glucose oxidase could significantly promote an increase in the organic matter degradation rate of compost by 3.8% 〜4. 1%, which may be attributed to acid accumulation caused by enzymatic hydrolysis pretreatment. In addition, medium temperature amylase and p-gluconase effectively accelerated the ammonification process of compost, while glucose oxidase was beneficial for the accumulation of n让rate nitrogen, significantly increasing the nitrate nitrogen content by 6・ 0% ・ The results indicated that exogenous enzymes can produce a chain reaction of enzymes, stimulating each other separately p-gluconase and dehydrogenase. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】The study was carried out to evaluate the feasibility and efficacy of feeds produced by fermented kitchen waste to spotted-brown chickens as a partial replacement of basal diets, with a view to providing basic data for the resource utilization and promotion of kitchen waste feed.【Method】One-day-old spotted-brown chickens were selected, and 0% (CK), 10% and 20% fermented kitchen waste feeds (FKWF) were added to the basal diet, and the amount of basal diet was reduced accordingly. At the 63rd day of the test period, the growth performance, slaughter performance and nutritional performance indexes such as crude protein, crude fat, calcium, phosphorus, zinc, selenium, inosinic acid and amino acids in chicken meat were measured.【Result】The results of broiler growth performance showed that the differences in feed-to-weight ratios between broilers in the 10% and 20% FKWF groups and CK were not significant, however, broilers in the 10% FKWF group had the highest weight. The results of slaughter performance showed that there were no abnormality in the skin color, muscle tissue elasticity, pH and odor of broilers of 10% and 20% FKWF groups, and the differences in organ coefficients were not significant compared with that of CK; the results of muscle nutritional performance showed that the crude protein contents of chicken meat in 10% and 20% FKWF groups increased by 7.50% and 3.42%, phosphorus contents increased significantly by 11.44% and 4.37%, and inosinic acid contents increased significantly by 7.10% and 6.00%; the fresh-flavored amino acid (FAA), sweet amino acid (SAA), essential amino acid (EAA), and total amino acid (TAA) were significantly higher in 10% and 20% FKWF groups than those in CK; aspartic acid, glycine, alanine, valine, isoleucine, leucine, tyrosine, phenylalanine, histidine and cysteine were significantly increased by 4.49%to 12.79% compared with CK; aspartic acid, valine, isoleucine, and leucine in the 20% FKWF group were significantly increased by 3.37% and 5.74%, compared with CK.【Conclusion】It is feasible and effective to replace the basal diet by a certain proportion of biofeed produced by fermented kitchen waste to feed broilers, which can save feed costs and improve economic benefits.

Black soldier fly is a worldwide resource insect, which is often added to animal feed because of its rich contents of protein, fatty acids, chitin, chitosan and antibacterial peptides. In addition, because its larvae live in saprophytic life, it can transform the treated organic matter into the nutrients it needs at the maximum efficiency. In recent years, it is often used in the harmless treatment of feces or waste, and it has become a hot spot of concern. The overview of the application research of black soldier fly larvae and the research status of larvae in feed application were reviewed, harmless treatment and challenges were discussed in detail. We hope to provide literature reference for the basic research and subsequent industrial production application of black soldier fly larvae. [ABSTRACT FROM AUTHOR]

Chitosan, a deacetylated form of chitin, is renowned for its exceptional biocompatibility and antibacterial capabilities, making it a material of choice in various biomedical applications such as antimicrobial disinfection and drug delivery. This study, rooted in the principle of sustainable development of waste utilization, employs shrimp shells—an everyday kitchen waste—as the raw material for extracting chitin and preparing chitosan . Comprehensive characterization techniques are conducted to substantiate the viewpoints in the paper, leading to the development of a chitosan-based antibacterial gel. Employing a gradient science popularization program, we captivate audiences ranging from kindergarten children to university students and the general public, illuminating the allure of chemistry. The study aims to spark public interest in the subject, inviting everyone to discard preconceived notions and rediscover the intrinsic beauty of chemistry from a more enlightened vantage point. [ABSTRACT FROM AUTHOR]

Improper disposal of food waste results in pollution of land and water. The efficient treatment of kitchen waste has gradually become a hot topic due to the garbage classification policy. During the process of disposal and transportation of kitchen waste, viscosity is a considerable and necessary factor. It may directly affect the model selection of key equipment and the determination of technological parameters. The study on determination of viscosity of kitchen waste is introduced into physical chemistry experiment as a practical application case. Combining with the engineering practice, the viscosity of kitchen wastes with different composition, different solid content and stirrer speeds were investigated. The results and influencing factors were analyzed. We aim to provide some theoretical basis and suggestion for the model selection of equipment and the parameters of the engineering design of kitchen waste an aerobic digestion. The improved experiment can enhance students’ awareness of applying what they have learned in real application, enhance their understanding of the comprehensiveness and complexity of engineering problems. In this process, inspire the students to think about the most efficient treatment of kitchen waste as a potential resource utilization, cultivate students’ innovate disciplinary literacy based on carbon peak and green environmental protection, and strengthen social responsibility. [ABSTRACT FROM AUTHOR]

【Objective】 The study was carried out to evaluate the feasibility and efficacy of feeds produced by fermented kitchen waste to spotted-brown chickens as a partial replacement of basal diets, with a view to providing basic data for the resource utilization and promotion of kitchen waste feed. 【Method】 One-day-old spotted-brown chickens were selected, and 0% (CK), 10% and 20% fermented kitchen waste feeds (FKWF) were added to the basal diet, and the amount of basal diet was reduced accordingly. At the 63rd day of the test period, the growth performance, slaughter performance and nutritional performance indexes such as crude protein, crude fat, calcium, phosphorus, zinc, selenium, inosinic acid and amino acids in chicken meat were measured. 【Result】 The results of broiler growth performance showed that the differences in feed-to-weight ratios between broilers in the 10% and 20% FKWF groups and CK were not significant, however, broilers in the 10% FKWF group had the highest weight. The results of slaughter performance showed that there were no abnormality in the skin color, muscle tissue elasticity, pH and odor of broilers of 10% and 20% FKWF groups, and the differences in organ coefficients were not significant compared with that of CK; the results of muscle nutritional performance showed that the crude protein contents of chicken meat in 10% and 20% FKWF groups increased by 7.50% and 3.42%, phosphorus contents increased significantly by 11.44% and 4.37%, and inosinic acid contents increased significantly by 7.10% and 6.00%; the fresh-flavored amino acid (FAA), sweet amino acid (SAA), essential amino acid (EAA), and total amino acid (TAA) were significantly higher in 10% and 20% FKWF groups than those in CK; aspartic acid, glycine, alanine, valine, isoleucine, leucine, tyrosine, phenylalanine, histidine and cysteine were significantly increased by 4.49%to 12.79% compared with CK; aspartic acid, valine, isoleucine, and leucine in the 20% FKWF group were significantly increased by 3.37% and 5.74%, compared with CK. 【Conclusion】 It is feasible and effective to replace the basal diet by a certain proportion of biofeed produced by fermented kitchen waste to feed broilers, which can save feed costs and improve economic benefits. [ABSTRACT FROM AUTHOR]

In order to explore the effect of kitchen waste addition ratio on the aerobic co-composting process of chicken manure and wheat straw, different proportions of kitchen waste were added to the mixed system with a dry weight ratio of chicken manure to wheat straw of 1∶ 5, and aerobic co-composting was performed using a forced intermittent ventilation aerobic composting device. The results showed that in the mixed system of chicken manure and wheat straw, when the proportion of kitchen waste was 0. 05 and 1, the com- posting pile entered the high temperature period ( > 50 ℃ ) earlier than other treatments and maintained for 8 days, with higher organic matter removal rate (13. 35% and 18. 20%, respectively) and germination index (116. 3% and 120. 6%, respectively) . When the addition ratio of kitchen waste was higher than 1, the pile achieve the high temperature period was later and the time maintained was shorter. Adding kitchen waste reduced pH and EC value of the pile, and improved the removal rate of organic matter (13. 35% ~ 20. 63% ) . Also, scanning electron microscope showed the straw surface was obviously broken then others. Redundancy analysis ( RDA) showed that pH, zinc, EC were the key environmental factors affecting the changes of GI and VS during composting and showed positive relationship. Therefore, appropriate addition of kitchen waste can promote the composting of chicken manure and wheat straw. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Anaerobic digestion is a valuable strategy for environmentally-friendly and sustainable disposal of kitchen waste. However, anaerobic digestion of kitchen waste (KWAD) is prone to acidification, which can cause poor reaction outcomes. Utilising conductive materials can ameliorate hydrogen, acid and ammonia inhibition during KWAD, ultimately enhancing methane production. This technique is widely applied to increase methane yield from anaerobic digestion. An analysis of conductive materials to promote methanogenesis in KWAD indicates that applying such materials can enhance methane production, alleviate acid and ammonia inhibition, enrich functional microorganisms, and replace conductive pili and c-type cytochromes for direct interspecies electron transfer. Additionally, metagenomics has shown that conductive materials can increase the expression of functional genes on microbial metabolism, ultimately improving the activity of key enzymes in the methanogenic process. Finally, it is recommended that the combination of macrogenomics, macrotranscriptomics and macroproteomics should be used to investigate KWAD's mechanism and to anticipate future engineering applications that reduce treatment expenses and ensure environmentally responsible disposal. [ABSTRACT FROM AUTHOR]

To guide the engineering application of bio-drying of kitchen waste, the effect of process conditions (bulking agent, proportion of bulking agent, air-flow rate) on bio-drying of kitchen waste were investigated three bulking agents, four proportions of bulking agent and four gradients of air-flow rate were selected in bio-drying process. Temperature, moisture content and volatile solid(VS) removal rate were analyzed to assess the bio-drying effect. The results show that adding sawdust can shorten the heating phase and prolong the thermophilic phase. The moisture content reduction of adding sawdust is 31. 97%, 18. 57% higher than control group with only kitchen waste. Adding 15% sawdust shows the best bio-drying effect. The highest temperature is 63. 8 ℃ and the moisture content reduces by 32. 36% . Different air-flow rates affect temperature accumulation and moisture loss of materials. At an air-flow rate of 0. 4 L/ (kg·min), the organic matter consumption is the least and water removal effect is the best. In the actual application of bio-drying of kitchen waste, 15% sawdust can be considered as the bulking agent, and air-flow rate is 0. 4 L/ (kg·min). [ABSTRACT FROM AUTHOR]

A large number of wastes with high organic matter, high oil and high moisture content are produced in the world every year. If not properly disposed of, it will pose a great threat to the ecological environment and human health. The harmless treatment and resource utilization of these organic wastes are important means to solve this problem. At present, insect biotransformation technology represented by the black soldier fly is one of the most potential strategies to deal with organic waste pollution. This technology has low energy consumption and low emissions, and has good social, ecological and economic benefits, which will lay a solid foundation for the construction of a harmonious ecological system. This paper describes the biological characteristics of the black soldier fly, the biological transformation of organic wastes such as kitchen waste, livestock and poultry manure, the synergistic effect of microorganisms in this process and the utilization of larval resources, and analyzes the development prospect of the black soldier fly. [ABSTRACT FROM AUTHOR]

This study aims to explore the effect of fermentation on the transformation of kitchen waste by black soldier fly, so as to provide reference for the treatment and resource utilization of kitchen waste. A total of 7 experimental groups were set up, including the unfermented group and the fermentation group for 1 to 6 days respectively, each group with 3 replicates. After the fermentation, 5 g three-day-old black soldier fly larvae were injected into each experimental group, and the substrate temperature and the growth and development index of black soldier fly larvae were determined during the feeding process, the composition of black soldier fly, the content of nutrient in worm sand and the effect of kitchen waste transformation were determined. In this study, the black soldier fly raised by kitchen waste fermented for 2 days did not grow normally, and the black soldier fly other experimental groups all grew normally. The crude protein content of the black soldier fly raised by unfermented kitchen waste was significantly higher than that of other experimental groups (P<0.05), and the crude fat content of the soldier fly raised by kitchen waste fermented for 6 days was significantly higher than that of other experimental groups (P<0.05). The contents of nutrient components of worm sand fermented for 2 days and 3 days conformed to the standard of organic fertilizer, the contents of crude protein, crude fat, and organic matter, total phosphorus, total potassium and in the worm sand fermented for 2 days were significantly higher than those in other experimental groups (P<0.05). The reduction rate of kitchen waste unfermented, fermented for 5 days and fermented for 6 days was significantly higher than kitchen waste fermented for 2 days (P<0.05), which increased by 20.00%, 18.37% and 20.88% respectively. The bioconversion rate of kitchen waste fermented for 5 days and 6 days was significantly higher than that for 2 days (P<0.05), which increased by 15.14% and 13.85% respectively. The kitchen waste fermented for 5 days and fermented for 6 days could reach higher reduction rate and bioconversion rate after transformed by black soldier fly. The kitchen waste unfermented was beneficial to the crude protein accumulation of black soldier fly, and the kitchen waste fermented for 5 and 6 days was beneficial to the crude fat accumulation of black soldier fly. The kitchen waste fermented for 2 days and 3 days still had high nutrient content after transformation. [ABSTRACT FROM AUTHOR]

Carbon-rich agroforestry auxiliary materials can be regulated to improve the humification and quality in aerobic composting of food wastes. However, it is still unclear on the effects of different auxiliary materials on the humification in food waste composting and their corresponding microbially driven mechanisms, thus limiting the effective selection and utilization of auxiliary materials. Herein, three typical carbon-rich agroforestry auxiliary materials were selected fromdifferent sources, including garden waste, corn straw, and watermelon vine. A systematic investigation was then implemented on their effects and mechanisms on the organic humification in food waste composting. Some parameters were then measured, such as the organic matter fraction, humic substances, and their precursors. Moreover, the high-throughput sequencing and Functional Annotation of Prokaryotic Taxa (FAPROTAX) database were also used to analyze the succession and function of the microbial community during composting. Results showed that the addition of 15% corn straw (wet weight) effectively adjusted the matrix structure to enrich the functional bacteria and thus enhance the compost maturity. Specifically, the watermelon vine with the high protein content was promoted the rapid temperature increase at the beginning of composting, but unfavorable to maintain the thermophilic stage for better product humification. In contrast, the garden waste and corn straw addition were enriching more bacteria (such as Ureibacillus, Bacillus, Oceanobacillus, and Flavobacterium) for the xylan and cellulose degradation at the thermophilic, cooling, and mature stages. Such enrichment in turn promoted the conversion of organic matter into humus precursors (i.e., polyphenols and amino acids) for stable humic acid production. Especially, the corn straw as an auxiliary material promoted the humification by 75%, indicating the accelerated degradation of organic matter. Anyway, the corn straw can be expected to effectively increase the bacteria with the lignocellulosic degradation function. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The feasibility analysis of hydroheat fertilizer production based on the actual collected kitchen waste was conducted, and the content of organic matter,total nutrient, humus,pH,electrical conductivity, heavy metal and fecal coliform bacteria were evaluated at 130,145,160,175,190 ℃,respectively. The results show that the highest content of organic matter in kitchen waste is 89. 75%, maintained above 73.55%,nitrogen,phosphorus and potassium content above 6.4% ; the increased temperature is conducive to the formation of humus, the content is 344 g/kg at 190℃,83%,the humization rate is first in- creased and then decreased, maximum 0.4 at 175 °C. After testing, the pH was decreased slowly with the increase of temperature and the conductivity was just the opposite, and the content of heavy metals and fecal coliform bacteria met the requirements of the relevant fertilizer standards [ABSTRACT FROM AUTHOR]

[Objective]To explore the effects of different types of kitchen wastes on the growth and development of T. molitor with a view to resource reuse of kitchen wastes. [Method]Kitchen waste was divided into washed and unwashed groups, rice, vegetable and meat groups, the effects of different feeding environments such as high oil and high salt conditions, starch, cellulose, and protein on the growth and development, mortality, pupation rate, protein and fat content of the worms were studied. [Result]The larvae of T. molitor were able to ingest the nutrients from kitchen waste for growth, and the utilization rate of kitchen waste in the washed group was significantly higher than that in the unwashed group; the mortality of larvae feeding on the unwashed groups were significantly higher than that in the control group and the washed groups; the pupation rate and fat content in the meat group with washed were significantly higher than all other groups. [Conclusion]Kitchen waste can be used to raise T. molitor to supplement nutrients, and it is recommended that washed kitchen waste can significantly reduce mortality, and the meat group with high protein content can increase the fat content of the worms and improve pupation rate. [ABSTRACT FROM AUTHOR]

Objective: To solve the problems of low dehydration rate of solid-liquid separation device and discharge not free of kitchen waste. Methods: By Optimizing the parameters of the key parts of the solid-liquid separation device, modeling the solid-liquid separation device based on Creo, analyzing the extrusion process through EDEM simulation software, the optimized screw shaft prototype was made and verified. Results: The optimized spiral shaft structure parameters were conveying distance 373 mm, compression distance 180 mm, compression end diameter 96 mm, spiral blade diameter 98 mm and axis length 553 mm; the force range of solid-liquid separation device was 2.7~4.5 N, wtih average force of 3 N, and discharge speed range of 1.3 ~ 4.7 m/s with average speed of 1.9 m/s. Conclusion: The dehydration rate of kitchen waste solid-liquid separation device is significantly improved, the discharge is smooth, and the dehydration effect is better than that before optimization.

Objective: To study the physical and geometric factors that affect the extrusion effect between particles in the spiral extrusion dewatering device for kitchen waste, and to provide reference for selecting the parameters of the spiral extrusion and dewatering device. Methods: Based on the discrete element method, the state of the extruded particles was analyzed, and the extrusion situation of the material particles in the device was simulated by changing the filling coefficient, spiral speed and inclination angle. Results: When there was some inclination angle in the screw extrusion dehydration device with variable pitch, the filling coefficient increased and the rotation speed up, and the extrusion pressure between the material particles increased accordingly. Conclusion: When the filling rate was 60%, the screw speed was 60 r/min, and the angle was 15°, the extrusion performance of the screw extrusion device could be significantly improved.

Kitchen waste has the characteristics of complex components and differences in texture characteristics in rural areas. A control system based on PLC was designed for the screw press pretreatment with automatic pressure regulation of screw press, equipment cleaning, abnormal feeding handling, working condition monitoring, key data collection and other functions. The system could control the screw press device to treat kitchen waste automatically and realize solid-liquid separation and solid reduction. The screw press control system was tested under the conditions of 0-32 ℃ in different seasons all year round. The results show that the control system can realize automatic running according to the system logic requirements. The system can control the device to steady state within 240 s and keep the control accuracy within 5 percent of the setting value. The drive motor operates stably within 38%-50% of the rated current, and the control system can well match the screw device for kitchen waste pretreatment. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Bioprocess Engineering is the property of Chinese Journal of Bioprocess Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South China Agricultural University is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There is a huge amount of kitchen waste in China, and aerobic composting is the main way of its fertilizer utilization. However, traditional aerobic composting often has problems such as insufficient supply of auxiliary materials and large odor emission. In order to reduce the addition of auxiliary materials, ensure the composting process and reduce odor emission, different proportions (0%, 25%, 50%, 75% and 100%, signed CK, R25, R50, R75, R100 respectively) of kitchen waste composting clinker (recycling) were explored. The mechanism of sawdust as an alternative auxiliary material on the composting efficiency of kitchen waste. The impact of clinker reuse on the composting process of kitchen waste was evaluated through the physical and chemical properties, maturity, odor emission and dynamic changes of bacterial community in the aerobic composting process. The results show that the replacement of 50% sawdust (R50) with recycled materials could promote the composting temperature rising, moisture content decreasing, pH increasing, GI increasing, bacterial diversity increasing, NH3 emission and reduce the emission of H2 S. At the end of composting, the moisture content of R50 is 42. 17%, pH is 7. 49, GI is 88. 30%, and the cumulative emissions of NH3 and H2 S are 0. 57 g/ kg and 0. 28 g/ kg, respectively, which promotes the relative abundance of Proteobacteria, Actinobacteria, Bacteroidetes, Chloroflex and Acidobacteria. Therefore, in the production practice, it is suggested to add 10% recycled materials instead of auxiliary materials (sawdust) for aerobic composting of food waste. [ABSTRACT FROM AUTHOR]

High-temperature aerobic composting has been ever-increasing developed rapidly for the fastest way to make high quality compost without any foul odors. However, the greenhouse gas (GHG) can also be produced during composting, including CH4 and N2O. In this study, a 35-day aerobic co-composting of kitchen waste and yard trimming (chipped stems) was carried out in 60 L forced aerated static composting reactors, in order to reduce the GHG emission during composting. Three commercial microbial agents were also added to compost materials, including the VT1000 compound consortia (VT), Bacillus subtilize (BS), and Bacillus licheniformis (BL). Among them, the addition of fungi was 1.5% of the dry weight of all raw materials. The treatment without bacterial agents was used as the control (CK). Furthermore, CH4 and N2O emissions during composting were monitored to investigate the effect of the microbial agents on the GHG emission. The results showed that the microbial agents significantly accelerated the maturity of compost with the rise of temperature, whereas, relatively reduced the GHG emission in the varying degrees. The duration of high temperature in all treatments was fully met the harmless requirements, in terms of reactor heating. But the treatment with the microbial agents presented the better secondary heating. The fastest temperature recovery and the highest temperature were achieved in the VT, followed by the BS, and the BL was slower than the CK. In maturity, the electric conductivity and pH value in all treatments were met the industrial requirements of compost quality. Specifically, the uninoculated microbial agent failed to the rot standard in the CK treatment. A slightly better compost maturity was obtained in the BS treatment, compared with the VT and BL. Among the GHG emission reduction, the N2O emission was accounted by 76.83%-88.57% of the total as the CO2-C equivalent, indicating the much higher amount than that of CH4. The peaks of emission occurred at the initial and mature stage. The CH4 emission peak occurred at the cooling stage, where the cumulative emissions reached 1.65%-2.40% of the total GHG emissions equivalent. The cumulative CH4 emissions in the four treatments were ranked as the CK>BL>BS>VT in the descending order. As such, the best performances (18.89%) of the CH4 and N2O emission reduction were achieved in the VT and BS treatment, respectively. The reduction rates were 49.22%, 61.86%, and 35.32% in the BS, VT, and BL treatment, respectively. The total GHG emissions equivalent were 95.84 (CK), 52.31 (VT), 42.03 (BS), and 62.49 kg/t (BL). Compared with the CK, the best total GHG mitigation was obtained in the BS treatment, with the reduction rate of 56.15%, the BL treatment was the lowest of 34.80%, while the VT treatment was 45.42%. The N2O abatement was better performed than methane with the inoculants, ranging from 35.32% to 61.87%. Taken together, the best effect was achieved in the treatment with 1.5% BS. Therefore, the microbial agents can be expected to effectively mitigate the GHG for the better quality of composting products. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Given the problem of mutual pollution among components in the process of garbage collection and transportation after classification, taking the kitchen waste in Maojian District of Shiyan City as the research object, the physical and chemical properties of the kitchen waste were determined, and the maturity index and ammonia changes in the kitchen waste compost and the kitchen waste+straw compost were compared. The results show that after fine classification, the purity of degradable organic matter of kitchen waste in Maojian district was about 80%, the moisture content 71%, the average TOC 458.16 g/kg, the pH 4.72, and the C/N ratio 33.4. According to the change of maturity index during the composting process, the combined composting of kitchen waste and straw had better maturity than the single composting of kitchen waste; the amount of leachate produced in kitchen waste+straw composting was 0, while the leachate produced in kitchen waste composting mainly occurred in the early stage of composting, accounting for 18.26% of the total amount of composting. In terms of gas production, the peak of ammonia production appeared in the middle and late stage of kitchen waste+straw composting, and the production was slightly higher than that of kitchen waste composting.

Effective disposal of organic wastes has been one of the most important issues for the resource utilization of solid wastes. The degradation rate of organic components as a key factor can pose a serious impact on the composting process. In this study, a series of experiments were performed on the microbial agents and various ventilation systems, in order to evaluate the co-composting performance of kitchens, green wastes, and exhausted tea on a pilot scale. An optimal compound ratio was also achieved to verify the strengthening effect of co-composting. The specific organic components included the fat crude, fibers, and protein in the mixed ingredients during composting. Specifically, kitchen waste, green waste, and exhausted tea were selected as the main raw materials. An aerobic composting was then carried out to control the ventilation and the type of microbial agents in a pilot composting plant. Some parameters were selected to fully evaluate the technical feasibility and economic viability of the co-composting system, including the temperature, water content, the carbon to nitrogen ratio, total nutrients, organic matter content, seed germination index, and hygienic characteristics. The results showed that the optimal combination was the self-developed microbial agents under the intermittent ventilation pattern, where the ratio of compound agents for the co-composting was that m(Aspergillus oryzae): m(Bacillus licheniformis): m(Candida lipolytica): m(Trichoderma viride): m(Azotobacter chroococcum) = 1.5:1:1.2:2:1. Meanwhile, the microbial agents presented a stronger removal effect of the specific organic component in the mixed ingredients, when the inoculation amount was 1‰. Three classic phases were obtained in the temperature of the mixed ingredients during 10 days of drum composting, including heating, thermophilic, and cooling phases. Furthermore, the maximum temperature was up to 68.6℃, while the high-temperature period (65℃ or higher) remained for 7 days. The ratio of water content and carbon to nitrogen declined from 63.5% to 30.1%, and 31.5 to 9.6, respectively, during the entire composting. The total nutrient (9.8%) and organic content (43%) were superior to the Agricultural Industry Standard NY 525-2021. Meanwhile, the seed germination index of the composting product reached up to 88.3%, indicating the perfect hygienic characteristics of composting (3 or fewer fecal coliforms per grams, no ova of roundworm was found). For economic feasibility, the co-composting system was applied for the domestic waste treatment in a district with a population of 30 000 in the Hengqin area of Zhuhai, Guangdong Province, China. A systematic analysis was made to consider the revenues (including waste disposal, organic fertilizer products, and scrap recycling revenue) and expenses (including utilities, salary, transportation, landfill disposal, venue rental, machinery and equipment depreciation, and unforeseeable expenses) during practical application. The average disposal cost was required as low as (248.67±19.89) yuan/t. As such, a process control strategy can be recommended to recycle the kitchen wastes, green wastes, and exhausted tea in the ecosystem, instead of being discarded as solid wastes. The short processing time can be widely expected to accelerate the degradation rate of organic matters for better compost quality during resource utilization. Meanwhile, an improved process control system can be used for the organic waste composting in a rotary drum reactor. The finding can provide a strong reference to effectively treat the environmental pollution of organic wastes in the large-scale kitchen waste, green waste, and exhausted tea at low cost. The recycling of organic waste resources can greatly contribute to reducing landfill disposal for less environmental pollution. [ABSTRACT FROM AUTHOR]

This paper introduces and compares the dewatering pretreatment technology of high-moisture kitchen waste, including the principle, main process flows and relative equipment of three kinds of pretreatment technology, namely physical technology, heat.drying technology and biological technology. And the dehydration treatment of high moisture kitchen waste should be a combination of mechanical technology and biological technology and that the bio.drying technology is more suitable for dehydration treatment of high moisture kitchen waste due to its advantages, such as shorter processing time and higher dehydration efficiency were found. In addition, in areas with heat source available, the combined technology of bio-drying and thermal drying will achieve a better drying effect. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the increasing amount of perishable waste, its impact on the environment is increasing. Studies have shown that despite its pollution characteristics, perishable waste has the potential to be reused as a resource after disposal by various technologies through which the toxicity of perishable waste can be minimized. This review summarizes the treatment effects, disadvantages, and applications of traditional perishable waste disposal technologies（landfilling, incineration, and smashing）, biological resource utilization approaches（feed treatment, anaerobic fermentation, aerobic composting, etc.）, and some new disposal technologies. The impact of waste classification on perishable waste disposal is also discussed. This review may provide theoretical references for the development of perishable waste deposal and resource utilization technologies and promote the further development of perishable waste disposal technology in China. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A large amount of kitchen and garden wastes is ever increasing, with the rapid development of urbanization in China. Kitchen waste is characterized by rich free fat content, high water and salt content. The inappropriate pore structure and organic composition can inhibit the organic degradation during aerobic composting, thereby leading to nitrogen loss in the form of ammonia volatilization. Garden waste is rich in cellulose, hemicellulose, lignin, and high-carbon substances, particularly hard to be degraded directly. Alternatively, a co-composting of kitchen and garden wastes can improve the physicochemical characters to make the mixed materials more suitable for composting. Therefore, the current work aims to investigate the co-composting feasibility of kitchen and garden wastes. The ratios of kitchen and garden wastes were set as 4∶1 (N1), 3∶1 (N2), and 2∶1 (N3) (dry weight basis, w/w). A 28-day experiment was conducted in the self-developed closed system of aerobic composting. The total material weight, the moisture content, and the aeration rate of composting mixtures were 2.5kg, 75%, and 0.2L/kg DM/min, respectively. Some indexes were recorded during the process, including the fermentation temperature, pH, C/N, germination index (GI), NH3 and cumulative emissions, total N, organic N, ammonium N, and nitrate nitrogen. The specific rule was revealed to the nitrogen transformation and ammonia volatilization loss. The results showed that the temperature increased faster than other treatments, when the ratio of kitchen and garden waste was 2∶1 (N3), indicating the highest fermentation temperature (63.4℃). Meanwhile, the GI in N3 treatment exceeded 80% on the 21st day, meaning that the fermentation was significantly accelerated. The GI values of three treatments at the end of the process were 75.77%, 81.54%, and 84.50%, respectively. The products in the N2 and N3 treatment reached the standard of complete decomposing (>80%), while, those in the N1 only met the standard of basic decomposing (>60%). Therefore, a strong recommendation was given that the proportion of kitchen waste should not be higher than 80% of materials in the process of waste co-composting. The total nitrogen content decreased in the N1 and N2 treatment, whereas, it increased in the N3 fermentation. A high pH of products was obtained, due mainly to the fact that part of organic nitrogen was converted into ammonium nitrogen. The total nitrogen loss in N3 was the lowest at the end of composting, especially lower than that in the N1 and N2 by 30.30% and 12.96%, respectively. The nitrogen transformation demonstrated that the high fraction of garden waste reduced the NH3 emission and the loss of ionic nitrogen, thereby promoting the conversion of ammonium nitrogen to organic nitrogen and nitrate nitrogen, indicating a higher nitrogen content in compost products. An optimal ratio of kitchen waste to garden waste was 2∶1, indicating the treatment is feasible. The co-fermentation of kitchen and garden wastes can greatly contribute to the reduction of nitrogen loss. The finding can provide potential theoretical support to the co-composting for kitchen and garden wastes. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The resource utilization and research status of the main urban and rural organic wastes, such as animal excrement, crop straw, kitchen waste and urban sewage sludge, were analyzed. Several problems restricting resource utilization of these organic waste were raised. It also put forward some suggestions and countermeasures from the aspects of legal guarantee, top-level design, policy support and development of technology, in order to provide an important reference for the resource utilization of organic waste in urban and rural areas. [ABSTRACT FROM AUTHOR]

Natural kitchen waste biochar(NKB)and magnetic kitchen waste biochar(MKB)were prepared by pyrolysis and coprecipitation method using food waste as raw material. The effects of pyrolysis temperature, pyrolysis time, adsorbent dosage, adsorption time and the pH of solution on the adsorption capacity of methylene blue(MB)were investigated. The results showed that the optimum adsorption capacity of NKB was obtained at the pyrolysis temperature of 450 °C and the pyrolysis time of 1 h. When the MKB was 1.0 g·L-1, the adsorption time was 20 min, and pH was 9, the adsorption capacity and removal rate of MB arrived 97.94% and 9.2 mg·g-1, which was 18.54% and 1.6 mg·g-1 higher than that of NKB, respectively. For MKB, after 4 cycles regeneration, the removal rate of MB was still above 90%. The adsorption process of kitchen waste biochar for MB could be described by Langmuir isothermal adsorption model. [ABSTRACT FROM AUTHOR]

2 strains of efficient bacteria for the aerobic degradation on kitchen waste were identified by biology microbes identification system and 16S rDNA gene sequence analysis. After the genomic DNA was extracted，the sequences of 16S rRNA gene were amplified by PCR with the bacterium universal primers and the purified PCR products were directly sequenced. The corrected sequences were aligned with Megalign 7. 0 and the phylogenetic tree was constructed. The results of phylogenetic analysis showed that the C95 belonged to Ochrobactrum or Stenotrophomonas; C132 belonged to Pseudomonas putida. The results of biology tests showed that the 2 strains were Ochrobactrum grigrnonense and Pseudomonas sutida，respectively [ABSTRACT FROM AUTHOR]

The aerobic degradation bacteria in kitchen waste was isolated and cultivated. By qualitative and quantitative screening from 202 strains, 4 strains could degrade cellulose, grease, protein and starch under aerobic condition. The 4 strains were identified by using the molecular biology techniques. The strains C116 and C132 belong to Pseudomonas putida. The strain C95 belongs to Ochrobactrum pseudogrignonense. The strain C126 is Brevibacterium epidermidis. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plackett -- Burman and central composite designs were employed to screen and optimize the significant factors for the enhancement of lactic acid production from kitchen waste. The results of Plackett -- Burman experiments showed that lactic acid bacteria TD175, glucoamylase, tween80 and cellulase were the positive significant factors, while sterilization affected the fermentation negatively. Optimum conditions for the lactic acid fermentation of kitchen waste were determined by central composite design as follows: TD175 6.6%, glucoamylase 160 U/g, cellulase 60 U/g, Tween -80 0.08% and temperature 45 °C. Under these conditions, lactic acid concentration in the fermentation broth reached 66.13 g/L after 40 h, and about 0.53 g lactic acid was produced from one gram of dry kitchen waste. Lactic acid production from kitchen waste need not sterilization operation and extra nutrient, thus it is very economical. [ABSTRACT FROM AUTHOR]