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Existing continuous flow reactors (CFR) utilized for the investigation of aerobic granular sludge (AGS) exhibit structural complexity and suboptimal energy efficiency. An innovative aeration self-circulating CFR (Zier rector) was employed in this study for the cultivation of AGS. The experiment was performed 202 days using real municipal wastewater under varying operating conditions. A hydraulic retention time of 10 h and adequate influent organic matter resulted in a chemical oxygen demand removal efficiency of 85%, an ammonia nitrogen removal efficiency exceeding 92%, and a total nitrogen removal efficiency ranging from 60% to 70%. The particle size increased when the up-flow velocity was maintained between 9.8 and 18 m/h, the self-circulating multiple times ratio was sustained within 12–30 times, and the food-to-microorganism was set within 0.2–0.6 g COD/(g MLSS·d). Ultimately, the mass proportion of sludge with a particle size larger than 0.2 mm was 75%, with 42% exceeding 0.5 mm. The stability of AGS and the treatment efficacy of the Zier process were influenced by the temperature and volume ratio of the nonaerated to the aerated zones. The Zier process demonstrates enhanced advantages and application potential, rendering it a more appealing option for a broader spectrum of water treatment facilities. [Display omitted] • Processing performance of a new Zier-AAOO reactor structure was examined. • V up at 8–27 m/h and F/M at 0.2–0.6 g COD/(g MLSS·d) facilitated AGS formation. • An aeration volume equalled to 1/13th of the reactor to provide circulating power. • Zier-AAOO realized 85% COD removal efficiency and 70% nitrogen removal efficiency. • Variable construction designs expand the application scenarios of Zier process. [ABSTRACT FROM AUTHOR]

• Energy-efficient retrofitting of existing buildings. • Using a new metaheuristic called Modified Supply-Demand-based Optimization Algorithm. • Multi-objective optimization method for decision-making. • Maximizing energy-savings and Minimizing payback period. Investing in energy-efficient retrofitting of existing buildings requires a robust decision-making framework. This study develops a multi-objective optimization technique to assist designers in minimizing payback time and maximizing energy savings within a specified initial investment. The proposed method utilizes a novel metaheuristic, the Modified Supply-Demand-Based Optimization Algorithm (MSDOA), to achieve optimal decisions. The model was tested on nine case studies involving buildings with various facilities, demonstrating its effectiveness. For example, an investment of $190,000 resulted in a payback period of less than three years and energy savings of over 10 % of the baseline consumption. The model considers initial investment, net present value (NPV), payback period, and energy targets as constraints. To evaluate the model's robustness, a sensitivity analysis was performed, examining the impact of varying initial investments, energy savings miscalculations, auditing errors, changes in electrical power costs, and interest rates. The results indicate that higher investments consistently lead to increased energy savings, though the payback period may vary. The MSDOA showed superior convergence speed compared to other algorithms, ensuring more reliable and accurate optimization outcomes. This study confirms the validity of the proposed design and highlights its potential for significant energy savings and financial benefits in building retrofitting projects. [ABSTRACT FROM AUTHOR]

• Indoor thermal environment and AC usage behavior was investigated for low-quality centrally heated dwellings. • 90% of AC trigger temperature is 15 ℃ for the living room and 14 ℃ for the bedroom. • The heating demand drivers of cool housing are identified by heteroskedasticity-robust Ordinary Least Square. • The study presents new knowledge for appropriate way to meet actual heating demand while reducing energy use. • Relationships between indoor temperature, heath and energy use are discussed. In northern China, district heating systems without terminal control typically serve thousands of end-users, thus inevitably some users suffer from insufficient warmth and others are overheated indoors due to hydraulic imbalances. This paper aimed to understand the indoor thermal conditions and the actual heating demand in low-quality centrally heated dwellings. The driving force of heating demand was analyzed based on a smartphone survey of 233 households in cold climates, and field measurements of winter indoor thermal environment and AC supplemental heating behavior were conducted in a sample of 13 cool dwellings. Logistic regression and heteroskedasticity-robust Ordinary Least Squares were adopted to assess AC usage patterns and driving forces of heating demand, respectively. New knowledge has been gathered regarding average temperatures of 17.4 ℃ and 16.8 °C in cool housing living rooms and bedrooms, respectively, outside the human thermal comfort zone. Simultaneously, intermittent and partial AC usage patterns induced by time and air temperature were observed in these cool end-users for the comfort. The average daily running time of AC devices was 2.0 h for the living room and 1.8 h for the bedroom. There were statistically significant base linking occupants' heating demands to education level, household income, tenure type, presence of children, thermal experience and heating system. However, it was not a significant factor for household size. In addition, a rebound effect of building energy efficiency improvements on the interior temperature was also noticed. The results of this study shed light on better and target-oriented residential internal temperature or heating system design for both thermal comfort requirements and energy-savings. [ABSTRACT FROM AUTHOR]

Abstract: Energy-efficient lighting is one of the key measures for addressing electric power shortages and climate change mitigation, and fluorescent lamps are expected to dominate the lighting market in China over the next several years. This review presents an overview on the emissions and risk of mercury from fluorescent lamps during production and disposal, and discusses measures for reducing the mercury risk through solid waste management and source reduction. Fluorescent lamps produced in China used to contain relatively large amounts of mercury (up to 40mg per lamp) due to the prevalence of liquid mercury dosing, which also released significant amounts of mercury to the environment. Upgrade of the mercury dosing technologies and manufacturing facilities had significantly reduced the mercury contents in fluorescent lamps, with most of them containing less than 10 or 5mg per lamp now. Occupational hygiene studies showed that mercury emissions occurred during fluorescent lamp production, particularly in the facilities using liquid mercury dosing, which polluted the environmental media at and surrounding the production sites and posed chronic health risk to the workers by causing neuropsychological and motor impairments. It is estimated that spent fluorescent lamps account for approximately 20% of mercury input in the MSW in China. Even though recycling of fluorescent lamps presents an important opportunity to capture the mercury they contain, it is difficult and not cost-effective at reducing the mercury risk under the broader context of mercury pollution control in China. In light of the significant mercury emissions associated with electricity generation in China, we propose that reduction of mercury emissions and risk associated with fluorescent lamps should be achieved primarily through lowering their mercury contents by the manufacturers while recycling programs should focus on elemental mercury-containing waste products instead of fluorescent lamps to recapture mercury from the waste stream cost-effectively. [Copyright &y& Elsevier]

Abstract: Improvement of residential environments has recently been promoted by the Korean government as part of its energy-saving measures. The objective of this research is to develop a decision support model for selecting the multi-family housing complex with the potential to be effective in saving energy. In this research, 362 cases of multi-family housings located in Seoul were selected to collect characteristics and data on gas energy consumption from 2009 to 2010. The following were carried out: (i) using the Decision Tree, a group of multi-family housings was established based on gas energy consumption; (ii) using case-based reasoning, a number of similar multi-family housings were retrieved from the same group of multi-family housings; and (iii) using a combination of genetic algorithms, artificial neural network, and multiple regression analysis, prediction accuracy was improved. The results of this research can be useful in the following: (i) preliminary research for continuously managing the gas energy consumption of multi-family housings; (ii) basic research for predicting gas energy consumption based on the characteristics of multi-family housings; and (iii) practical research for selecting an optimum multi-family housing complex (with the potential to be effective in saving gas energy), which can make the application of an energy-saving program more effective as a decision support model. [Copyright &y& Elsevier]

Abstract: Magnetic properties of a recently developed Fe-based amorphous alloy with a high saturation induction of 1.65T are reviewed. The increased saturation induction is fully utilized in transformers with reduced magnetic losses, physical sizes and audible noises, minimizing some of the drawbacks of amorphous metal-based transformers based on a currently available amorphous alloy. Impacts of this on the worldwide energy savings and reduction of greenhouse gas emissions are discussed. A recent effort in achieving a saturation induction beyond 1.65T in nanocrystalline alloys is mentioned. [Copyright &y& Elsevier]