The results of this study provide deep insights into the effects of CeO2 nanocatalyst morphology on the Hg oxidation. Landfill biocovers are an efficient strategy for the mitigation of greenhouse gas emissions from landfills. A complex interplay between key physical and reactive processes occurs in biocovers and affects the transport of gas components. Therefore, numerical models can greatly help the understanding of these systems, their design and optimal operation. In this study, we developed a 3-D multicomponent modeling approach to quantitatively interpret experimental datasets measured in the laboratory and in pilot-scale landfill biocovers. The proposed model is able to reproduce the observed spatial and temporal dynamics of CH4, O2 and CO2 migration in biocovers under different operating conditions and demonstrates the importance of dimensionality in understanding the propagation of gas flow and migration of gas components in such porous media. The model allowed us to capture the coupled transport behavior of gas components, to evaluate the exchange of gas fluxes at the interface between the biocover surface and free air flow, and to investigate the effects of different gas injection patterns on the distribution of gas components within biocovers. The model also helps elucidating the dynamics and competition between methane oxidation and respiration processes observed in the different experimental setups. The simulation outcomes reveal that increasing availability of methane (i.e., higher injection flow rates or higher fractions of CH4 in the injected gas composition) results in progressive dominance of methane oxidation in the biocovers and moderates the impact of respiration. Tire wear particles (TWPs) were one of the source categories of microplastics, and some countries consider it the largest. In the case of Korea, the number of vehicles per a kilometer of road is the highest among 30 OECD countries. Therefore, the concentration of TWPs is considered high. This study aims to estimate TWPs emission factor by using warranty period of tire, driving distance per vehicle per day, weight of tire, and ratio of weight loss of tire, and then, suggests TWPs emission amount by using annual driving distance and emission factor of TWPs of each type of vehicle. As a result, the emission factor of TWPs in Korea appeared as in the following 45-57 mg/vehicle·km (average 51.1 mg/vehicle·km) for passenger cars, 224 mg/vehicle·km for lightweight trucks, 799 mg/vehicle·km for buses, and 949 mg/vehicle·km for heavyweight trucks. The total amount of TWPs to be generated in a year was calculated as 51,795-54,581 tonnes/year (average 53,188 tonnes/year). The amount of TWPs appeared in the order of heavyweight trucks, buses, passenger cars, and lightweight trucks; the contribution of tires of each type of vehicles, to the emitted amount of TWPs, appeared with insignificant differences. This study evaluated the physicochemical and morphological properties of pectin and chitosan particles combined with sugarcane vinasse for soil fertilization applications. Particles were obtained by adding the biopolymeric solutions (pectin or chitosan solution) dropwise into the crosslinking solutions (calcium chloride 1% in ethanolic solution or tripolyphosphate 5% aqueous solution) followed by drying. Vinasse enhanced pectin gel stability improving pectin/vinasse particle properties. Physicochemical characterization indicated that vinasse nutrients were properly incorporated in both pectin and chitosan matrices. Particles showed spherical shape, with an average diameter of 3 and 2 mm for the pectin and chitosan particles with vinasse, respectively. Chitosan particles, compared to pectin, showed lower swelling capacity and solubility and higher mechanical resistance indicating a denser and more compact polymer network. Both particles were able to hinder water evaporation rates from sandy soil under water stress conditions. Biobased particles with vinasse added show potential to be applied as soil fertilizer representing an alternative to use and disposal of this expressive wastewater from sugar and alcohol industries. There is a growing need to recycle construction and demolition waste (CDW) in order to treat the huge amount of CDW in many metropolises of China. However, the CDW recycling industry is still in its initial stage and developed unevenly across various areas of China. In spite of some qualitative discussions, the quantitative analysis of crucial policies to the development of CDW recycling industry was overlooked. Through literature review, nine influential policy instruments were identified in term of three categories, i.e. control and command policy, market-based policy and information-based policy. The stepwise regression analysis was employed to explore the relationships between the influential policies and the development level of CDW recycling industry in 52 sample Chinese cities. The results demonstrated that Green Product Label, Charge and Tax and Technical Standards had statistically significant association with the development of CDW recycling industry in sample cities. In the surveyed cities, Charge or Tax was the most common policy tool (84.6%), but Green Product Label (7.7%) and Technological standards (11.5%) were rather less frequently employed. According to the results, Green Product Label and Technical Standards should be given higher priority. In addition, landfill charge should be introduced as a fundamental impetus. These results provide directions for other cities to facilitate the development of their CDW recycling industry. The aim of this paper is to investigate the impact of pretreating macroalgal residue (MAR) from agar-agar extraction and its co-digestion with sewage sludge on methane production and the agronomic quality of the digestates produced. https://www.selleckchem.com/products/a1874.html First, different pretreatments were assessed on BMP tests. Among milling technologies used, knife milling with a 4 mm-screen improved methane production by 25%. The MAR was then knife milled before alkaline, acid and thermal pretreatment. KOH pretreatment (5% TS basis, 25 °C for 2 days) led to the highest methane improvement. It was applied to semi-continuous anaerobic digestion and methane production achieved 237 Nml/gVS which was 20% higher than the control (198 Nml/gVS). In comparison to MAR mono-digestion, co-digestion with thickened activated sludge produced less methane (184 Nml/gVS) but reduced H2S emission by 91%. None of the digestates was toxic for the germination or growth of wheat and tomato plants. Particularly, co-digestion had the highest impact on tomato plant dry weight (+94% compared to soil alone) mainly due to the phosphorous brought by sludge.
The results of this study provide deep insights into the effects of CeO2 nanocatalyst morphology on the Hg oxidation. Landfill biocovers are an efficient strategy for the mitigation of greenhouse gas emissions from landfills. A complex interplay between key physical and reactive processes occurs in biocovers and affects the transport of gas components. Therefore, numerical models can greatly help the understanding of these systems, their design and optimal operation. In this study, we developed a 3-D multicomponent modeling approach to quantitatively interpret experimental datasets measured in the laboratory and in pilot-scale landfill biocovers. The proposed model is able to reproduce the observed spatial and temporal dynamics of CH4, O2 and CO2 migration in biocovers under different operating conditions and demonstrates the importance of dimensionality in understanding the propagation of gas flow and migration of gas components in such porous media. The model allowed us to capture the coupled transport behavior of gas components, to evaluate the exchange of gas fluxes at the interface between the biocover surface and free air flow, and to investigate the effects of different gas injection patterns on the distribution of gas components within biocovers. The model also helps elucidating the dynamics and competition between methane oxidation and respiration processes observed in the different experimental setups. The simulation outcomes reveal that increasing availability of methane (i.e., higher injection flow rates or higher fractions of CH4 in the injected gas composition) results in progressive dominance of methane oxidation in the biocovers and moderates the impact of respiration. Tire wear particles (TWPs) were one of the source categories of microplastics, and some countries consider it the largest. In the case of Korea, the number of vehicles per a kilometer of road is the highest among 30 OECD countries. Therefore, the concentration of TWPs is considered high. This study aims to estimate TWPs emission factor by using warranty period of tire, driving distance per vehicle per day, weight of tire, and ratio of weight loss of tire, and then, suggests TWPs emission amount by using annual driving distance and emission factor of TWPs of each type of vehicle. As a result, the emission factor of TWPs in Korea appeared as in the following 45-57 mg/vehicle·km (average 51.1 mg/vehicle·km) for passenger cars, 224 mg/vehicle·km for lightweight trucks, 799 mg/vehicle·km for buses, and 949 mg/vehicle·km for heavyweight trucks. The total amount of TWPs to be generated in a year was calculated as 51,795-54,581 tonnes/year (average 53,188 tonnes/year). The amount of TWPs appeared in the order of heavyweight trucks, buses, passenger cars, and lightweight trucks; the contribution of tires of each type of vehicles, to the emitted amount of TWPs, appeared with insignificant differences. This study evaluated the physicochemical and morphological properties of pectin and chitosan particles combined with sugarcane vinasse for soil fertilization applications. Particles were obtained by adding the biopolymeric solutions (pectin or chitosan solution) dropwise into the crosslinking solutions (calcium chloride 1% in ethanolic solution or tripolyphosphate 5% aqueous solution) followed by drying. Vinasse enhanced pectin gel stability improving pectin/vinasse particle properties. Physicochemical characterization indicated that vinasse nutrients were properly incorporated in both pectin and chitosan matrices. Particles showed spherical shape, with an average diameter of 3 and 2 mm for the pectin and chitosan particles with vinasse, respectively. Chitosan particles, compared to pectin, showed lower swelling capacity and solubility and higher mechanical resistance indicating a denser and more compact polymer network. Both particles were able to hinder water evaporation rates from sandy soil under water stress conditions. Biobased particles with vinasse added show potential to be applied as soil fertilizer representing an alternative to use and disposal of this expressive wastewater from sugar and alcohol industries. There is a growing need to recycle construction and demolition waste (CDW) in order to treat the huge amount of CDW in many metropolises of China. However, the CDW recycling industry is still in its initial stage and developed unevenly across various areas of China. In spite of some qualitative discussions, the quantitative analysis of crucial policies to the development of CDW recycling industry was overlooked. Through literature review, nine influential policy instruments were identified in term of three categories, i.e. control and command policy, market-based policy and information-based policy. The stepwise regression analysis was employed to explore the relationships between the influential policies and the development level of CDW recycling industry in 52 sample Chinese cities. The results demonstrated that Green Product Label, Charge and Tax and Technical Standards had statistically significant association with the development of CDW recycling industry in sample cities. In the surveyed cities, Charge or Tax was the most common policy tool (84.6%), but Green Product Label (7.7%) and Technological standards (11.5%) were rather less frequently employed. According to the results, Green Product Label and Technical Standards should be given higher priority. In addition, landfill charge should be introduced as a fundamental impetus. These results provide directions for other cities to facilitate the development of their CDW recycling industry. The aim of this paper is to investigate the impact of pretreating macroalgal residue (MAR) from agar-agar extraction and its co-digestion with sewage sludge on methane production and the agronomic quality of the digestates produced. https://www.selleckchem.com/products/a1874.html First, different pretreatments were assessed on BMP tests. Among milling technologies used, knife milling with a 4 mm-screen improved methane production by 25%. The MAR was then knife milled before alkaline, acid and thermal pretreatment. KOH pretreatment (5% TS basis, 25 °C for 2 days) led to the highest methane improvement. It was applied to semi-continuous anaerobic digestion and methane production achieved 237 Nml/gVS which was 20% higher than the control (198 Nml/gVS). In comparison to MAR mono-digestion, co-digestion with thickened activated sludge produced less methane (184 Nml/gVS) but reduced H2S emission by 91%. None of the digestates was toxic for the germination or growth of wheat and tomato plants. Particularly, co-digestion had the highest impact on tomato plant dry weight (+94% compared to soil alone) mainly due to the phosphorous brought by sludge.
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