Journal of Cleaner Production最新文献

Small island social-ecological systems are increasingly vulnerable to the combined impacts of human activities and environmental changes, making focused vulnerability analyses critical for sustainable governance. In this study, Gouqi Island, a remote island, was selected as the research site to establish a comprehensive vulnerability assessment framework based on the Vulnerability-Sensitivity-Danger (VSD) model. To account for potential interdependencies among indicators, a fuzzy integration method was employed to quantitatively assess vulnerability trends from 2016 to 2022. The analysis revealed that vulnerability reached its lowest point in 2018, peaked at 0.876 in 2020, and remained above 2016 levels through 2022, despite a slight decline. Additionally, machine learning techniques were used to identify key factors influencing vulnerability, highlighting indicators such as D24 (proportion of fisheries and tourism output), D41 (number of tourists), and D52 (aquaculture production) as particularly significant, though distinct from traditional sensitivity indicators. These findings inform the identification of critical factors affecting the island's sustainable development and lead to the proposal of adaptive governance strategies. The insights from this study provide valuable guidance for promoting sustainable development in similar remote islands.

Organizations play a crucial role in facilitating the transition to a circular economy. Implementing circular practices often begins with a material flow analysis (MFA) to identify issues and opportunities. However, existing MFA methodologies focus mainly on territorial applications and lack effectiveness at the organizational level. Conducting MFA at this level presents distinct challenges, requiring insights into dynamic material circulation and effective handling of heterogeneous data. Addressing this gap, this study introduces an innovative methodology tailored to organizational contexts. The developed methodology consists of six steps for conducting MFA while proposing an archetype-based approach capable of analyzing extensive and disparate datasets, coupled with bootstrapping and Monte Carlo simulation techniques, that considerably reduces the complexity of MFA execution. Furthermore, this methodology enables a comprehensive understanding of material flows within the system and provides a straightforward method for estimating uncertainty in mass estimations by incorporating confidence level calculations. A case study from a governmental organization is used to illustrate the proposed methodology.

Digital transformation has the potential to significantly impact household energy consumption (HEC) by promoting the adoption of energy-efficient technologies. This paper utilizes the time-varying Difference-in-Differences (DID) model to evaluate the causal effect of digital transformation on HEC within China's households. We find that HEC is positively impacted by digital transformation, as embodied by the "Broadband China" strategy; and the results remain reliable when many robustness tests are taken into account. Specifically, digital transformation has the potential to indirectly increase HEC by consumption upgrade and internet development mechanisms. The heterogeneity analysis reveals that the impact of digital transformation on HEC varies significantly across different household and regional. High-income, low skilled, rural areas, as well as households in areas with higher levels of development and marketization, are more likely to be affected by the digital revolution in production and consumption, which will inevitably lead to an increase in HEC. These insights are crucial for developing effective strategies to reduce HEC and promote sustainable development.

This study explores a novel integration of electro-physicochemical technologies to generate energy and treat water from combined food waste (FW) and blackwater (FW-BW), with BW containing waste activated sludge with simulated flush water. The FW-BW substrate was gravity-separated and pretreated with hydrodynamic cavitation (HDC). Solids from gravity separation were used for energy generation via anaerobic digestion (AD) alone or integrated with microbial electrolysis cells (AD-MEC). HDC pretreatment had 51.6% more CH₄ production in 5 days (266 mL CH₄/g VS) and 63% more in 30 days compared to AD without HDC. The CH₄ production after 5 days of digestion with HDC pretreatment (266 mL CH₄/g VS) was similar to the amount produced without HDC over 30 days (263 mL CH₄/g VS). Using MEC increased CH₄ production by 12.7% compared to AD-only. The liquids from gravity separation were treated with electrocoagulation (EC) at 15 V (90 min), which removed 96.2% of the chemical oxygen demand (COD) and 100% of the total suspended solids. The pilot scale design indicates that the AD-MEC and EC units would generate 1.4 times more energy than energy consumed through applying these novel technologies. These findings demonstration the applications of four technologies (HDC, AD, MEC, and EC) in an energy-efficient waste management approach, producing bioenergy and cleaner water for low-tier use, especially in areas lacking traditional waste treatment options.

Microwave as an efficient and clean energy, is easy integrated with DES pretreatment and biorefinery process to achieve process intensification for cleaner production and sustainable development. However, there are worries about its economic and environmental feasibility for application in biorefinery plant. This work conducted the techno-economic (TEA) and life cycle assessment (LCA) of the entire biorefinery process based on DES pretreatment by microwave heating (MH) for producing glucose, furfural and lignin from lignocellulose, of which the results were compared with conventional heating (CH). For pretreating equivalent biomass, the total yield of products obtained from MH-assisted process was 8.53% higher than that of CH-assisted process due to microwave intensification effect. From the perspective of cradle-to-gate LCA, the MH-assisted process saved energy demand of 5.82%, reducing the environmental impacts global warming (GW) and fossil resource scarcity (FRS) by 4.85% and 5.69%, respectively, relative to CH-assisted process. The main environmental hotspots of both two processes concentrated on the raw material extraction (RME), followed by product separation and solvent recovery (PSSR) stages. Based on economic evaluation, the specific values of TAC regarding one-ton product for MH- and CH-assisted processes were 3194.35 and 3400.37 $/(y⋅t), respectively. Therefore, the MH-assisted pretreatment possessed certain environmental and economic advantages due to product increasement, energy consumption reduction in the DES pretreatment, and burden reduction for subsequent enzyme hydrolysis. Compared to the single-product biorefinery, the multi-product biorefinery strategy was more sustainable and could maximize the advantages of microwave intensification. However, some issues about the design of microwave reactors and temperature monitoring must be considered to pursue scale-up biorefinery plant.

In the context of global climate change, all industries have put forward the requirements for carbon emission reduction. The effective use of water resources is the key to achieving carbon emission reduction, so it is particularly important to review the carbon dioxide emission equivalents of water resource utilization behaviors (CEE-WRUBs) of water users. However, existing research on CEE-WRUBs across various water sectors remains inadequate. Therefore, this study integrates the enhanced CEEA method, LMDI decomposition model, and IOA method to analyze CEE-WRUBs across diverse water use terminals. Then seeks their main driving factors and their transfer pattern among different industries, which are crucial to the realization of the global carbon neutrality objective. The results showed that: (1) China's CEE-WRUBs show a significant downward trend. Industrial water use emerges as the primary source of CEE, but the CEE-WRUBs of most industrial water terminals show a fluctuating downward trend. Grains' water use behavior (WRUBs) absorbed the largest CEE, reaching 14,698 Mt in 2020. (2) the water efficiency effect emerges as the predominant driver behind the increase in CEE-WRUBs most of the time, and holding a prominent position. The carbon emission intensity effect primarily steers the reduction of CEE-WRUBs. (3) the largest net outflow sector of WRUBs embodied carbon in 2007–2020 was transformed from basic material heavy industry (−153.54 Mt in 2007) to agriculture (−128.26 Mt in 2020). Most of the WRUBs embodied carbon of agriculture flows into light industry, while most of the WRUBs embodied carbon of basic material heavy industry flows into finishing heavy industry and construction. The methods and results of this study provide a potential reference for investigating the regional water-carbon relationship and advancing the global carbon neutrality objective.

Mangroves, as a crucial coastal ecosystem, possess significant carbon sink functions and play a key role in mitigating global climate change. This paper, based on the Zhanjiang Mangrove Afforestation Project in Guangdong, explores the development mechanisms and economic and ecological benefits of mangrove carbon sink projects through the lens of collective action theory and system dynamics modeling. The study finds that the primary reason for the unsustainable progression of mangrove carbon sink projects is the lack of intrinsic motivation among local villagers to engage in collective action. By constructing a system dynamics model, this paper quantifies the long-term impacts of mangrove carbon sink projects on local socio-economic welfare and proposes policy optimization recommendations. These recommendations include expanding income sources for local villagers, establishing carbon trading and ecological compensation mechanisms, and involving international non-governmental organizations. The findings of this study not only provide guidance for mangrove carbon sink projects in China but also offer valuable insights for the promotion of similar projects globally.

Boats require End-of-Life (EOL) management, especially those built with fibre-reinforced plastic/polymer materials because they are hard to dispose and have negative effects on the environment. The main challenge with EOL boats or abandoned and derelict vessels (ADVs) is the lack of sustainable disposal options for recycling and reusing composite plastics, which should be safe, managed, sustainable, and economically viable. Most efforts have focused on dealing with ADVs in water rather than on land. This study provides a systematic review of 101 studies of End-of-Life Boat (ELB) management and seeks methods to deal with derelict vessels, challenges in their management, potential solutions, and a comparison and assessment of EOL opportunities in terms of sustainability and circular economy. Research gaps were identified, and suggestions for future research directions were proposed. The marine industry faces gaps in practical implementation and understanding of sustainable principles and lacks effective regulations, cost-effective methods, and suitable technologies for sustainable management, particularly for recycling and reusing. The present review highlights the importance of a harmonized approach, financing mechanisms, sustainable dismantling and transport, material reuse and upcycling, industry partnerships, centralized recycling systems, and investments in research and innovation as crucial elements for enhancing the circular economy.

Rice paddies are not only sources of staple food for half of the global population but also account for nearly half of the anthropogenic greenhouse gas emissions (GHGs) of croplands. Carbon footprint (CF) is a key tool for identifying and weighting sources of the GHGs along the food supply chain, promoting the efforts to curb these emissions within the targets of the climatic change protocol of the Paris Agreement. We introduced a comprehensive global quantification of rice CF, including direct and indirect emissions and sinks of the GHGs of inputs production, packaging, transportation, and application, soil and plant systems, farm operations, and uses of the produced biomass until the end of life. Globally, the rice CF was 2430 kg CO₂eq. Mg⁻¹ grain in 2020, of which 46% and 42% were sourced from the Gate and Grave stages, respectively, after excluding 3265 kg CO₂eq. Mg⁻¹ grain, that is the assimilated C in plant biomass. Net GHGs emissions of soil, biomass mulching and burning, and farm operations accounted for 20, 17, and 63%, respectively of the Gate stage CF. Meanwhile, food consumption contributed to the Grave stage CF by 92%. The rice CF ranged between 14 and 4854 kg CO₂eq. Mg⁻¹ grain among countries, wherein, for example, the rice CF values in Indonesia, India, Vietnam, and Russia represented 9, 50, 97, and 122% of the global average. Southeast, South, and East Asia were the major contributors (35, 34 and 18%, respectively) to the atmospheric CO₂ load (2.4 Pg CO₂eq.) of global rice production and consumption. This CO₂ load will increase to 3.1 Pg CO₂eq. in 2100, driven by a 32% growth in rice consumption. Here, we suggested an optimistic strategy (green energy use, hybridization, improving use efficiency of the inputs, and reducing food losses) to reduce the CO₂ load by 60%.

A thorough understanding of the mechanisms involved in CO₂ chemical absorption is crucial for the development of efficient CO₂ capture technologies. Due to the insufficient insight into the interaction mechanism of different components in blended solutions, CO₂ absorption reactions were often categorized as unidirectional transfer between absorption products. In this study, the CO₂ absorption performance of binary blended solutions, including piperazine (PZ)/n-methyldiethanolamine (MDEA), ethanolamine (MEA)/MDEA, ammonia (NH₃)/MDEA, PZ/potassium carbonate (K₂CO₃), and NH₃/K₂CO₃, was investigated using a combination of experimental and computational methods. The CO₂ absorption mechanisms of “competitive reaction”, “transfer reaction” and “parallel reaction” in the binary blended solution system were proposed. Kinetic experiments revealed that different blended solutions had varying impacts on the process of CO₂ absorption. Among them, PZ/MDEA and MEA/MDEA solutions reduced the absorption rates by an average of 8% and 25%, respectively, compared to PZ or MEA component solutions. NH₃/MDEA and PZ/K₂CO₃ solutions had absorption rates similar to those of single NH₃/PZ component solutions. NH₃/K₂CO₃ solutions, on the other hand, exhibited an average increase of 17% in absorption rates compared to NH₃ solutions. Quantum mechanical (QM) methods were employed to evaluate of the absorption products and key processes in terms of kinetics and thermodynamics. Quantitative ¹³C NMR analyses were conducted to further investigate the interactions between components and the pathways of mass transport in blended solutions, which demonstrated proton transfer and CO₂/-COO transfer between adsorption products. This study highlights an accurate description of the transfer mechanisms of various blended systems for the enhanced CO₂ capture.