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The harmless treatment and resource utilization of the high boiling chlorosilane produced by products in the process of polycrystalline silicon production can be realized by using organic amine catalyst. The effects of reaction temperature and catalyst type on the catalytic cracking of high-boiling chlorosilane was investigated and the reaction mechanism was analyzed. The results showed that, using N,N-dimethylbenzylamine as the catalyst, at a reaction temperature of 130 ~ 135 °C, a reaction time of 1.5 h, and a catalyst amount of 8%, the yield of monosilane product could reach 79.99%. [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]

KIT-6 is a typical three-dimensional ordered mesoporous silica, which has a wide range of applications in the fields of catalysis and adsorption. By doping the framework Al to endow the KIT-6 material with acid sites, the adsorption performance of the Al-KIT-6 material for basic dye molecules can be significantly improved. However, it is difficult to controllably synthesize Al-KIT-6 with inorganic silicon and aluminum sources. In this study, a series of Al-KIT-6 materials were directly synthesized by a pH-controlled hydrothermal method with fly ash-based sodium silicate, which can induce Al atoms doping into the KIT-6 silicon framework. The texture properties of Al-KIT-6 were characterized by N2-physical adsorption, XRD, TEM, Al NMR, XPS and NH3-TPD. The results showed that the synthesized Al-KIT-6 material had an ordered mesoporous structure. Al was mainly doped into the framework of KIT-6 material, thereby significantly increasing the acid content and acid strength. The adsorption experiments of the synthesized Al-KIT-6 materials on basic methylene blue molecules showed that the adsorption capacity of the Al-KIT-6 materials increased with the increase of Al incorporation. The adsorption kinetic experiments showed that the adsorption process conformed to the pseudo-second-order kinetics, and the adsorption isotherm model fitting results showed that the adsorption process conformed to the Langmuir adsorption model. [ABSTRACT FROM AUTHOR]

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]

In order to solve the rural living garbage processing problems, we independently developed a unique technology of clean and comprehensive utilization of rural garbage resources, referred to as PGAS technology. Based on modern biodegradation and automatic sorting, we built a complete industrial chain with mixed domestic waste as mineral raw material. The garbage trucks transport rural garbage and directly discharged into the hopper. Quickly biofilm is sprayed to deodorize garbage, then the garbage bags are teared at the same time of feeding. At the transportation, we utilize magnetic and eddy current sorting to get metal products and residues, while the residue will be transferred into the tearing machine and the biological treatment silo, where the raw garbage is mixed by composite bacteria liquid and enzyme liquid. The organic pus would be pumped to anaerobic fermentation system, while the residue would be alternatively tearing through broken drum to main sorting system. By our innovated equipment, we obtain inorganic material as sand and glass, pulp and sundries like bamboo textiles, and pure plastic at last. The products would be further processing to industrial materials as required of market. The sand and gravel glass and other inorganic materials can produce hollow blocks, paving brick and sponge brick. The pulp would change to the pulp products which can be directly used for producing cardboard and corrugated paper. The plastic can be packaged directly to sale, or be used in oil refining, even can be further sorted to monomer plastic, such as PE, and to produce particles. The slurry is pumped into the biogas tank for producing the methane gas through anaerobic fermentation system, which can be reused as energy. And the slurry after anaerobic fermentation, through evaporation, can be sprayed into powder or granular fertilizer. This technology subverted the traditional mode of rural waste disposal, which is the only comprehensive utilization of rural garbage with all components. The whole processing line is close with no smelly gas. There is no sewer in the whole plant with no waste water emissions, the water is in circulation. There is no operator in the whole plant, the sorting is automatic. Take the PGAS demonstration project in Yuanqu County, Shanxi Province as an example. The project was completed in 2017 and has been put into operation for 1 year with a processing capacity of 100 t/d. The radiation area includes 2 towns and 3 townships with about 100 000 people. According to this waste plant’s operation data, treating 1 ton waste by PGAS, we can obtain the average amount of 65 kg organic fertilizer, 105 kg pulp, 124 kg plastic, 133 kg waste derived fuel, 135 kg sand, 55 kg methane and 11 kg metal. The cost is about 180 yuan, and the output value is about 325 yuan. The investment cost is nearly 40% less than that of incineration. After the sewage treatment, the removal rate of various pollution factors reaches 88.76% on average, which is used for recycling. It is proved that this technology can improve the efficiency of waste disposal. This technology has considerable economic benefits, is environmentally friendly, and has high promotion value. [ABSTRACT FROM AUTHOR]

In recent years, a large number of wastes increase rapidly with the agriculture and livestock development in China. However, these wastes aggravate environmental pollution and lead to cause resource wasting due to the lack of understanding on the agricultural and livestock wastes that as an available resource, especially using for organic fertilizer. Under the policy background of "speeding up the resources utilization of wastes ", in order to solve some problems on organic fertilizer utilization for wastes of agricultural and animal wastes, the innovation of technology and equipment should be speed up to utilize potential nutrients pool of wastes. It is of important to reduce the input of chemical fertilizer and to mitigate agricultural non-point source pollution, also has great significance to promote the green and healthy development for agriculture and guarantee the implementation of the strategy of "storing grain in the land" in China. Therefore, we analyzed the present situation for fertilizer utilization of agricultural and animal wastes in China using the total amount and utilization proportion of organic wastes. Also, we summarized the main ways and related technologies for fertilization utilization of wastes including crop straw returning, aerobic composting, returned by straw-animal-excretion, edible mushrooms cultivating, anaerobic digestion, charring or producing commercial organic fertilizer. However, there were many existing problems on the organic fertilizer utilization of agricultural and animal wastes such as the total amounts of waste was unclear and could not be collected unified, the sources quality of organic fertilizer from agricultural and animal wastes was uneven, the technology and equipment for organic fertilizer utilization was still lagging behind, the quality and market competitiveness of organic fertilizer was insufficient, the relevant policy guidance for organic fertilizer utilization of waste was lack. Meanwhile, we presented homologous countermeasures and suggestion according to these unsolved problems, which should be formulating collection and transportation systems of agricultural and animal wastes, improving core technology innovation on organic fertilizer utilization, strengthening the supervision of organic fertilizer market and enhancing the market competitiveness. These suggestions would promote to develop with the right direction for the organic fertilizer utilization of agricultural and animal wastes, and possibly some problems such as wastes disposal of large-scale livestock and poultry farm and crop straws using for organic fertilizer could be resolved, which also provide a reference for resource utilization of agricultural and animal wastes, especially the development of organic fertilizer utilization in China. Future, the technological innovation on optimized fermentation, non-hazardous treatment and organic fertilizer safe utilization of agricultural and animal wastes should be intensified in China. The new subject, new form, new industry for organic fertilizer utilization of wastes should be established to improve the clean process of livestock and the ecological production of wastes utilization. The utilization efficiency for organic fertilizer of agricultural and animal wastes would be increased by a newly formed situation including industrialization development, market-oriented management and scientific management and socialized service. Therefore, a newly historical opportunity for the organic fertilizer utilization of agricultural and animal wastes will be brought due to the development of science and technology, the increase of the environmental protection and the support of governmental policy in our country. [ABSTRACT FROM AUTHOR]

The university laboratory waste collection and disposal is one of the important contents in the laboratory management. The main waste from the university laboratory includes chemical waste, biological waste, waste water and gas, radioactive and electronic waste. Its amount is low, but it covers quite a wide range with complicated components. University laboratory waste contains a lot of poisonous and harmful substances, thus, mishandling on collection and disposal is quite harmful to the environment and humans. In this paper, we introduced the advanced safety management system of collection and disposal of Dutch university laboratory waste. Dutch universities set up a management organization dedicated to waste disposal. The classification of waste is clear, and the disposal method of each kind of waste is very detailed and operable. In particular, the classification and treatment of hazardous waste in laboratory and the personnel responsibility and management training system are worthy of learning and reference for Chinese universities. We proposed some ideas and suggestions in laboratory waste management in the universities of our country and gave a brief introduction to the effect of laboratory waste management in our university. [ABSTRACT FROM AUTHOR]