Dredging is one of the most effective methods for inhibiting the endogenous contamination of natural lakes. However, both the amount and the scope of dredging will be restricted if the disposal of the dredged sediment incurs considerable environmental and economic costs. The use of dredged sediments as a post-mining soil amendment for mine reclamation benefits both sustainable dredging and ecological restoration. This study incorporates a field planting experiment with a life cycle assessment to confirm the practical effectiveness of sediment disposal via mine reclamation, as well as its environmental and economic superiority over other alternative scenarios. The results show that the sediment offered plentiful organic matter and nitrogen for mine substrate, stimulating plant growth and increasing photosynthetic carbon fixation density, followed by enhanced plant root absorption and an improved soil immobilization effect on heavy metals. A 2:1 ratio of mine substrate to sediment is recommended to significantly promote the yield of ryegrass while reducing levels of groundwater pollution and soil contaminant accumulation. Due to the significant reduction in electricity and fuel, mine reclamation had minimal environmental impacts on global warming (2.63 x 10-2 kg CO2 eq./kg DS), fossil depletion (6.81 x 10-3 kg oil eq./DS), human toxicity (2.29 x 10-5 kg 1,4-DB eq/kg DS), photochemical oxidant formation (7.62 x 10-5 kg NOx eq./kg DS), and terrestrial acidification (6.69 x 10-5 kg SO2 eq./kg DS). Mine reclamation also had a lower cost (CNY 0.260/ kg DS) than cement production (CNY 0.965/kg DS) and unfired brick production (CNY 0.268/kg DS). The use of freshwater for irrigation and electricity for dehydration were the key factors in mine reclamation. Through this comprehensive evaluation, the disposal of dredged sediment for mine reclamation was verified to be both environmentally and economically feasible.

TiO 2 has demonstrated outstanding performance in electrochemical advanced oxidation processes（EAOPs） due to its structural stability and high oxygen overpotential.However,there is still much room for improving its electrochemical activity.Herein,narrow bandgap manganese oxide（MnOx） was composited with TiO 2 nanotube arrays（TiO 2 NTAs） that in-situ oxidized on porous Ti sponge,forming the MnO x -TiO 2 NTAs anode.XANES and XPS analysis further proved that the composition of MnO x is Mn 2 O 3 .Electrochemical characterizations revealed that increasing the composited concentration of MnO x can improve the conductivity and reduce oxygen evolution potential so as to improve the electrochemical activity of the composited MnO x -TiO 2 NTAs anode.Meanwhile,the optimal degradation rate of benzoic acid（BA） was achieved using MnO x -TiO 2 NTAs with a MnO x concentration of 0.1 mmol L -1 ,and the role of MnO x was proposed based on DFT calculation.Additionally,the required electrical energy（EE/O） to destroy BA was optimized by varying the composited concentration of MnO x and the degradation voltage.These quantitative results are of great significance for the design and application of high-performance materials for EAOPs.

Since 2019, Chinese authorities have actively attempted to improve the waste separation behavior of civilians with interventions such as publicity and supervision. Their focus was to study the residents' waste separation attitudes with questionnaires and not the actual separation behavior via objective investigation. Selecting Zhangjiagang in Yangtze Delta Region as study area, we focused to compare the effects of publicity and supervision on residents' actual separation performance before and after intervention implementation. Based on on-site collection of 810 waste bags, detailed composition analysis and physical properties observations in 3 communities (C1, C2, and C3), it was found that after 1-month supervision period in C2, the source separation rate of green and grey bins dramatically rose from 13% to 90%, 20%–72%, respectively, which led to marked differences in moisture content, bulk density, and lower heating value compared to before supervision. However, with 3-month publicity in C1 and C3, the source separation rates were still less than 30% in the 2 bins, almost no improvement. Furthermore, the multi-period supervision intervention demonstrated the source separation rates for 3-month supervision in green and grey bin (90% and 68% respectively) were actually identical with 1-month supervision (90% and 72%), which indicated that occasional residents' misclassification might contribute to the existence of separation rate thresholds. To achieve waste source separation across society, on-site supervision via supervisors beside the drop-off containers is suggested to be implemented, not just applying publicity.

This study compares the environmental impacts of a centralized natural gas combined cycle (NGCC) and a distributed natural gas-fired combined heat and power (CHP) energy system in the United States. We develop an energy-balance model in which each energy system supplies the electric, heating, and cooling demands of 16 commercial building types in 16 climate zones of the United States. We assume a best-case scenario where all the CHP's heat and power are allocated toward building demands to ensure robust results. We quantify the greenhouse gas (GHG) emissions, conventional air pollutants (CAPs), and natural gas (NG) consumption. In most cases, the decentralized CHP system increases GHG emissions, decreases CAP emissions, and decreases NG consumption relative to the centralized NGCC system. Only fuel-cell CHPs were able to simultaneously reduce GHG, CAP, and NG consumption relative to the NGCC-based system. The results suggest that despite their energy efficiency benefits, standard distributed CHP-based systems typically do not have enough benefits compared to an NGCC-based system to justify a reorganization of existing infrastructure systems. Because fuel-cell CHPs can also use hydrogen as a fuel source, they are compatible with decarbonized energy systems and may aid in the transition toward a cleaner energy economy.

Distributed energy systems (DES) are the focus of increasing attention as a means of improving the sustainability performance of power and heat production. However, many studies have shown that distributed energy systems have a higher cost than conventional centralized energy generation (CCEP). Previous studies on economic analysis of DES has generally overlooked the economic impacts of policy incentives, business depreciation, and emission taxes. This research aims to examine the reduction of the life cycle cost (LCC) for DES when the impact of U.S. policy incentives and emission taxes are considered. We first used a parametric model to find the optimal DES solution for three commercial building types under five climate zones in the U.S. Then, we calculated the LCC for each scenario and evaluated the cost-saving potential of feasible U.S. clean energy policy incentives, including federal tax credits, low-interest loans, and accelerated depreciation. Finally, we used the Air Pollution Emission Experiments and Policy model to quantify air pollutant emissions’ social cost for formulating emission tax on DES and CCEP. Results show that the social cost of centralized conventional energy production is significantly higher than the distributed energy systems. The bundle of feasible U.S. clean energy policies can reduce the cost of distributed energy systems by 67% on average. Suppose the social cost of energy-related emissions is also considered and charged as emission tax for energy generation. In that case, 50% of building energy supply scenarios for the distributed energy systems become cost-competitive as compared to CCEP.

A novel tannic acid -ferric (TA-Fe) complex coating was applied to commercially available cellulose triacetate (CTA) forward osmosis (FO) membrane to enhance membrane performance. Notably, the coated membrane attained a better water/salt selectivity than the control membrane and it had a mild water permeability loss of about 13.6%. Consequently, when the coated membrane is operated in the FO system, the reverse salt flux was smaller as compared to the uncoated commercially available membrane. Also, the rejection of three selected micropollutants improved and this is due to both increased membrane hydrophilicity and the decreased mem-brane effective pore size. In the membrane fouling tests, with the support layer facing the feed solution (PRO mode), the normalized water flux for the uncoated membrane decreased from 1 to about 0.4. For our membrane with a coating layer on the support layer side, the normalized water flux was higher than 0.5 after the test under the same conditions, confirming its improved antifouling property. The improvement was due to both the coated membrane?s decreased surface roughness and the increased interaction energy barrier between the foulant and membrane. These test results represent a new contribution to wastewater treatment using FO based on the success of the authors? novel coating method and its potential to offer multiple performance improvements in osmotic pressure-driven membrane processes.

Distributed energy systems (DES) are the focus of increasing attention because they have the potential to enhance the sustainability performance of energy generation. Previous DES researches evaluated various distributed energy technologies and systems from different aspects. However, there is still a research gap to evaluate and compare the multiple technology combinations and sizes for finding optimal energy solutions under various scenarios. This study aims to determine the best combination of technologies and their corresponding sizes for DES for various building types and climate zones in terms of life cycle environmental and economic impact. We developed parametric models (which considers dynamic hour by hour energy demand) for six commercially available distributed energy technologies and simulated the performance of them under various conditions. Then, we used a novel approach - multidisciplinary design optimization (MDO) to examine the billions of options (e.g., technologies, sizes, climate zone, Etc.) and identified the Pareto front with the optimal environmental and economic impact. According to MDO simulations, the microturbine-solar PVs-lithium ion battery and solid oxide fuel cells-solar PVs-lithium ion battery are two optimal combinations of technologies for three commercial building types for five climate zones. The DES can primarily reduce the environmental impact compared to conventional centralized energy production (CCEP) by 16-61% in all scenarios. However, the life cycle cost of DES is higher than CCEP, especially for SOFC-based DES. The microturbine-based DES is more cost-competitive and economical (about 65%, 32%, and 64% lower than SOFC-based DES for the small, medium, and large office, respectively).

Polyfluoroalkyl Substances (PFAS) such as perfluorooctanoic acid (PFOA) are resistant to biodegradation leading to adverse health outcomes. Therefore, PFAS removal from drinking water is paramount. Liquid-liquid extraction processes can remove them from water; however, the hydrophobic and oleophobic properties of PFOA lead to the low extraction efficiency and severe emulsification, especially for the ppm-levels concentration of PFOA. Therefore, we introduced ionic liquid (IL) methyltrioctylammonium bis(trifluoromethylsulfonyl)imide ([A336] [NTf2]) as extractant into octanol. We found that using hexadecyl trimethyl ammonium bromide (CTAB) as an extractant caused severe and stable emulsion. In comparison, [A336][NTf2] could suppress the emulsification with high extraction efficiency. The extraction performance of PFOA was examined as a function of various parameters. The results showed that the extraction efficiency was strongly dependent on the concentration of IL and aqueous pH. Further research revealed the extraction mechanisms at the molecular-level, and density functional theory (DFT) and molecular dynamic (MD) simulation agreed with the trends in the experiment. We determined that the extraction efficiency of PFOA from water could be up to 88.21 wt% for the optimized condition, indicating that the extraction system of [A336][NTf2] + octanol was efficient for separating PFOA from the diluted aqueous solution.

Increasing numbers of cement furnaces have applied selective catalytic reduction (SCR) units for advanced treatment of NO in the flue gas. However, the SCR catalysts may face various poisons, such as acidic, alkaline, and heavy metal species, in the fly ash. In this work, we studied the deactivation mechanisms of multipoisons (Ca, Pb, and S) on the CeO2-WO3/TiO2 catalyst, using the in situ diffuse reflectance infrared Fourier transform spectroscopy method. Calcium promoted the conversion of Ce(III) to Ce(IV) and, thus, (i) suppressed the redox cycle, (ii) decreased the NO adsorption (monodentate NO3- and bridged NO2-), and (iii) enriched the Lewis acid sites. Pb(IV) blocked Ce2(WO4)3, aggravating the electronegativity of W6+, which inhibited (i) the binding stability of tungsten and ammonia species, (ii) bridged NO3- (bonded to tungsten), and (iii) the Brønsted acid sites. The multipoisoning processes enriched O2- by repairing partial surface oxygen defects, which suppressed O22- and O-. Sulfur occupied the surface base sites and formed PbSO4 after Ce2(WO4)3 was saturated.

近年来,中国和世界一直致力于发展储能技术,为电网运行提供调峰、调频、黑启动、需求响应支持,并帮助解决可再生能源间歇性、不稳定性、不可调节性等问题.本文回顾总结了国内目前评价储能技术常用的技术指标和经济效益指标.并站在能源可持续发展的角度介绍了基于“能量”成本评价储能技术的新理念及方法,阐述了基于‘能量’成本评价不同技术节能潜力的必要性,引入了全生命周期能源投入存储回报(energy stored on Investment,ESOI)这一新指标.ESOI比值越高说明该技术“净能量”越高,生产对能源依赖度越低.本文研究对比了不同储能技术的ESOI,结果表明以压缩空气储能(CAES)和抽水储能(PHS)为代表的物理储能技术的ESOI远远大于电化学储能,其中,过去常用的铅酸电池(PbA)的ESOI最小,只有2.

Since the publication of the Report of the World Commission on Environment and Development in 1987, there have been numerous studies on sustainability. These studies created new knowledge and tools for understanding and managing complex coupled human and natural systems. In this Critical Review, we used a topic modeling technique to analyze 12 526 peer-reviewed research articles and identify the research questions and the approaches that were used or developed in each of the studies. These approaches were then classified by function. The analysis revealed twenty-three categories of research questions and seven functional approach classes design for sustainability, modeling of complexity, sustainability indicators, life cycle sustainability assessment, decision making support, sustainability governance, and engagement each of which is described here as an individual approach or tool within a larger sustainability toolbox. The article concludes with a discussion about using the sustainability toolbox as an integrated knowledge system to support transdisciplinary study and decision-making.

The osmotic heat engine is a promising technology for harvesting low-grade heat from different heat sources. However, a better understanding of the system performance, thermodynamic efficiencies, and suitable application circumstances (type of heat sources, system energy generation capacity, etc.) is needed before the transition can be made from conceptual design to practice. Firstly, the energy efficiency (eta(th)) and exergy efficiency (eta(X)) of a thermolytic osmotic heat engine (NH4HCO3 solution as the working fluid) were investigated in this study. It was found that the osmotic heat engine performs better when the operating temperature (heat source temperature) is lower (323 K). Additionally, a higher draw solution concentration and a lower feed solution concentration can increase both eta(X) and eta(th). Subsequently, the energy return on investment with either low-grade industrial waste heat or solar thermal energy acting as the heat source was calculated. It was found that different energy return on investment values can be obtained with different heat sources. The results show that when industrial waste heat is used as the heat source, a much higher energy return on investment value (approximately 55) can be obtained. This finding indicates that it is suitable to generate electricity from industrial waste heat using the osmotic heat engine. When solar thermal energy is used as the heat source the energy return on investment value is 1.3-2.2 because there is a large amount of embodied energy in the flat-plate solar collector. This study represents a step forward towards the practical application of the osmotic heat engine.

In this research, we develop a parametric life cycle assessment framework and evaluate the environmental and economic trade-offs of a distributed combined cooling, heating, and power system integrated with renewable energy and energy storage system (CCHP-RE-ESS). Also, we compare this to centralized conventional energy generation. The CCHP-RE-ESS system consists of microturbines, solar PVs, lithium-ion batteries, and other auxiliary system components. Using a parametric life cycle assessment approach, we learn the trade-offs environmental and economic impacts for various sizes of solar PVs arrays and batteries. The emission impact result from the parametric life cycle assessment is more accurate than the conventional life cycle assessment due to hourly-based simulation and parametric models for different system components. Our simulations show that the proposed system that follows the thermal load can primarily reduce the overall environmental impact as compared to the centralized conventional energy production for most building types and climate zones we studied. For example, the system can help a medium office in Atlanta reduce 46% of global warming impact, 98% of water usage, 93% of acidification impact, etc. In terms of cost, the life cycle cost of the proposed system is often higher than conventional energy generation while it is more economical for the small and large office than the medium office.