Emission Reduction Potential Research Articles

Experimental and numerical modeling of co-combustion of biomass gasification gas and natural gas in a non-premixed burner

Biomass gasification gas has the characteristics of low calorific value and great potential for carbon emission reduction. It is currently being widely used in traditional industries to replace fossil energy. Current burners fail to fulfill the demands for co-combustion of biomass gasification gas and natural gas due to singular structure. Moreover, understanding the blending methods, blending ratio, stability of combustion, and the emission rules of pollutants are not yet clear. This study proposes a non-premixed burner for the co-combustion of biomass gasification gas and natural gas (BG- NG). The effects of differing burner loads (P), excess air coefficients (α), and biomass gasification gas blending ratio (XBG) on the flame structure, pollutant (CO and NO) emission performance, and flame lift distance (HL) of this burner during the co-combustion of natural gas and biomass gasification gas, have been investigated via experimental and simulation methods. The results show that the optimalα and XBG are 1.4 and 40%, respectively, after co-combustion natural gas with biomass gasification gas. When α and XBG are 1.4 and 70%, the CO emission concentration is approximately 18.71 times that α and XBG are 1.4 and 40%. The minimum NO emission concentration is a mere 2.5 ppm. Under the same experimental conditions, the NO emission concentration decreased by 60% and the CO emission concentration decreased by 75% when co-combustion with 40% biomass gasification gas, compared to the combustion of natural gas. The analysis of flame lift distance indicates that the use of the non-premixed burner can reduce the flame lift distance from 22.5 mm to 4.1 mm. The simulation results found that co-combustion with biomass gasification gas can increase the flame propagation speed and enhance flame stability. The research in this manuscript contributes to meeting the safe operation requirements of industrial kilns with a high proportion of biomass gasification gas co-combustion. This is crucial for the development of industrial kilns, economic benefits, and low-nitrogen environmental protection.

The role of socio-demographic and psychological factors in shaping individual carbon footprints in Finland

Household consumption emissions are a major contributor to global greenhouse gas emissions, making them a vital target for emission reductions. While previous research has studied socio-demographic and situational factors in explaining the variation in individuals’ carbon footprints, a more comprehensive exploration of individual drivers, would benefit the development of effective and equitable mitigation policies. The current study examines associations between psychological and socio-demographic factors and carbon footprints of Finnish adults (n = 3,519). Income was found to be the strongest factor explaining the variation in carbon footprints. While environmental attitudes, perceived easiness and perceived importance of climate actions statistically explained differences in carbon footprints, the effect sizes were modest. The factors explaining variation in the carbon footprint varied across different domains (housing, travel, diet, and other consumption of goods and services), with psychological factors having a more substantial effect on diet compared to other domains. Overall, the findings suggest that tailoring policy interventions to reduce emissions from different domains to specific groups and factors could be beneficial. Furthermore, the greatest emission reduction potential lies among higher-income individuals. In the dietary domain, attitude-changing interventions could be more effective, while financial or choice architecture interventions might be better suited for other domains.

Analysis of spatial and temporal characteristics and evolution of green total factor productivity in agriculture in the lower Yellow River basin

The construction of ecological barriers in the Yellow River Basin represents a significant step toward reducing agricultural carbon emissions, achieving carbon neutrality, and reaching carbon peaking in China. The diverse agrarian development objectives of various regions within the basin have resulted in a heterogeneous approach to greening agriculture. Therefore, this paper will evaluate the development of carbon sink agriculture across 34 cities and municipalities in the lower Yellow River basin from 2008 to 2021 based on the EBM-GML model, and analyze the spatial-temporal evolution of agricultural green total factor productivity (AGTFP) in each region through the application of the Moran index, kernel density estimation, and spatial Markov chain analysis. The results demonstrate that agricultural carbon emissions in the Lower Yellow River Basin gradually decreased throughout the study period. Furthermore, overall carbon emission efficiency improved, indicating significant potential for further emission reduction. In addition, Agricultural Green Technology Progress (AGTC) has become a primary driver of AGTFP growth, while Agricultural Green Technology Efficiency (AGEC) has demonstrated a gradual upward trend. Locally, most areas are weakly connected and display an isolated development trend. The results of the kernel density analysis demonstrate a notable degree of mobility in the distributional dynamics of AGTFP growth, characterized by a gradual narrowing of the gap between locations. The transfer of (AGTFP) types in the lower reaches of the Yellow River Basin is stable, with a noticeable “club convergence” phenomenon, while geographical conditions significantly influence the transfer of AGTFP types in this region. Based on long-term trend predictions, the future trajectory of AGTFP in the lower Yellow River Basin appears optimistic and is expected to improve progressively, with the overall distribution tending toward equilibrium.

Analysis of Technological Pathways and Development Suggestions for Blast Furnace Low-Carbon Ironmaking

Under the global dual-carbon background, heightened public awareness of climate change and strengthened carbon taxation policies are increasing pressure on the steel industry to transition. Given the urgent need for carbon reduction, the exploration of low-carbon pathways in a blast furnace (BF) metallurgy emerges as crucial. Evaluating both asset retention and technological maturity, the development of low-carbon technologies for BFs represents the most direct and effective technical approach. This article introduces global advancements in low-carbon metallurgical technologies for BFs, showcasing international progress encompassing hydrogen enrichment, oxygen enrichment, carbon cycling technologies, biomass utilization, and carbon capture, utilization, and storage (CCUS) technologies. Hydrogen enrichment is identified as the primary technological upgrade currently, although its carbon emission reduction potential is limited to 10% to 30%, insufficient to fundamentally address high carbon emissions from BFs. Therefore, this article innovatively proposes a comprehensive low-carbon metallurgical process concept with the substitution of carbon-neutral biomass fuels at the source stage—intensification of hydrogen enrichment in the process stage—fixation of CCUS at the end stage (SS-IP-FE). This process integrates the cleanliness of biomass, the high-efficiency of hydrogen enrichment, and the thoroughness of carbon fixation through CCUS, synergistically enhancing overall effectiveness. This integrated strategy holds promise for achieving a 50% reduction in carbon emissions from BFs in the long processes. Critical elements of these core technologies are analyzed, assessing their cost-effectiveness and emission reduction potential, underscoring comprehensive low-carbon metallurgy as a pivotal direction for future steel industry development with high technological feasibility and emission reduction efficacy. The article also proposes a series of targeted recommendations, suggesting short-term focus on technological optimization, the medium-term enhancement of technology research and application, and the long-term establishment of a comprehensive low-carbon metallurgical system.

A Quantitative Method of Carbon Emission Reduction for Electrochemical Energy Storage Based on the Clean Development Mechanism

Electrochemical energy storage (EES) plays a crucial role in reducing the curtailed power from wind and solar PV power (WSP) generation and enhancing the decarbonization effects of power systems. However, research on quantifying the carbon emission reduction effects of EES methods in the engineering field is still insufficient, which constrains decision-makers from making intuitive assessments of the decarbonization effects of energy storage. Therefore, drawing on the principles of the clean development mechanism (CDM), this paper proposes a method for quantifying the carbon emission reductions of a standalone EES station. Firstly, based on the design principles of building marginal emission factor in the CDM, a method for calculating the BM weight of WSP is proposed. Secondly, three quantification methods for the carbon emission reductions of EES are presented based on the complexity of the calculations. Lastly, to analyze the impacts of different operational conditions and calculation methods on the carbon emission reduction of energy storage systems, a dispatch model is constructed for various operational scenarios. The results of the case study indicate that different calculation methods yield varying results in terms of the carbon emission reductions of energy storage systems, with the sharply value method yielding the smallest reduction and the output curve method yielding the largest reduction. Additionally, when considering the losses in the state of charge (SOC) of an energy storage system and reducing the overall output fluctuations of WSP-EES, the carbon emission reduction potential of the energy storage will decrease. This study establishes a theoretical basis for quantifying the carbon emission reductions of standalone electrochemical energy storage systems, aiding decision-makers in gaining a deeper understanding of the role of electrochemical energy storage in carbon reduction and operational value.

Application of GIS in Introducing Community-Based Biogas Plants from Dairy Farm Waste: Potential of Renewable Energy for Rural Areas in Bangladesh

Dairy production is one of the most important economic sectors in Bangladesh. However, the traditional management of dairy cow manure and other wastes results in air pollution, eutrophication of surface water, and soil contamination, highlighting the urgent need for more sustainable waste management solutions. To address the environmental problems of dairy waste management, this research explored the potential of community-based biogas production from dairy cow manure in Bangladesh. This study proposed introducing community-based biogas plants using a geographic information system (GIS). The study first applied a restriction analysis to identify sensitive areas, followed by a suitability analysis to determine feasible locations for biogas plants, considering geographical, social, economic, and environmental factors. The final suitable areas were identified by combining the restriction and suitability maps. The spatial distribution of dairy farms was analyzed through a cluster analysis, identifying significant clusters for potential biogas production. A baseline and proposed scenario were designed for five clusters based on the input and output capacities of the biogas plants, estimating the location and capacity for each cluster. The study also calculated electricity generation from the proposed scenario and the net greenhouse gas (GHG) emissions reduction potential of the biogas plants. The findings provide a land-use framework for implementing biogas plants that considers environmental and socio-economic criteria. Five biogas plants were found to be technically and spatially feasible for electricity generation. These plants can collectively produce 31 million m3 of biogas annually, generating approximately 200.60 GWh of energy with a total electricity capacity of 9.8 MW/year in Bangladesh. Implementing these biogas plants is expected to increase renewable energy production by at least 1.25%. Furthermore, the total GHG emission reduction potential is estimated at 104.26 Gg/year CO2eq through the annual treatment of 61.38 thousand tons of dairy manure.

Use Efficiency, Reduction Potential, and Effects of Fertilizers on Carbon Emissions in China’s Major Citrus Regions

Enhancing the efficiency of fertilizer utilization and advancing fertilizer reduction efforts constitutes a pivotal initiative for augmenting the quality and productivity of the citrus industry; this constitutes an indispensable prerequisite for attaining green and sustainable development. Utilizing panel data from seven prominent mandarin-producing regions and seven prominent tangerine-producing regions in China spanning from 2002 to 2022, this study employed the stochastic frontier analysis (SFA) method to develop a translog production function model for precisely measuring the fertilizer use efficiency for mandarins and tangerines. Employing the calculated optimal fertilizer use rates, we further ascertained the fertilizer reduction potential for mandarin and tangerine; then, we estimated the associated carbon emission reduction potential within these key citrus regions. The research revealed the following findings: the overall level of citrus fertilizer use efficiency in China is comparatively low, with the mean values for mandarin and tangerine fertilizer use efficiency being merely 0.4403 and 0.3887, respectively, indicating substantial room for improvement by approximately 60%; substantial potential exists for decreasing fertilizer use in China’s citrus industry, with average reduction potentials of 66.27% for mandarins and 64.83% for tangerines, signifying a notable redundancy in fertilizer application within major citrus-producing areas. The magnitude of carbon emission reduction potential through the diminution of citrus fertilizer use is tremendous. When optimal fertilizer rates are applied, the average carbon emission reductions resulting from fertilizer reduction in mandarins and tangerines amount to 815.8681 kg/hm2 and 602.3551 kg/hm2, respectively. The average carbon reduction potential for mandarins and tangerines reach levels of 55.9673% and 61.1299%, respectively, both surpassing the threshold of 55%. Significant differences exist in the technical efficiency of fertilizer input, reduction potential, and carbon emission mitigation potential among major citrus-producing regions. Citrus orchards in Guangdong exhibit higher potential for fertilizer reduction but demonstrate a relatively low level of technical efficiency. In contrast, Hunan Province shows an opposite trend, necessitating the development of region-specific strategies. Therefore, to minimize citrus fertilizer use and augment the technical efficiency of citrus fertilizer, it is imperative to comprehensively integrate and promote the “three new” technologies aimed at reducing fertilizer use and enhancing its efficiency within the citrus industry; implement a regional coordinated development strategy for citrus fertilizer reduction; and intensify policy guidance, publicity, and training efforts related to citrus fertilizer reduction, efficiency enhancement, and carbon emissions reduction.

Balancing economic and environmental strategies in regional hinterland transport: a dynamic network cross efficiency analysis

Regional seaport hinterland transport network development strategies aim to maximize economic benefits while simultaneously mitigating environmental impacts. Tracking hinterland transport’s environmental efficiency is crucial for monitoring and improving sustainable transport policies in regional seaports. Previous research mainly employs static self-assessment models under a single objective, overlooking multi-modal hinterland transport routes. This study introduces network cross-efficiency data envelopment analysis models to assess the efficiency of regional seaport hinterland transport, balancing economic and environmental strategies. We further employ the cross-efficiency global Malmquist productivity index to examine dynamic changes and emission reduction potential. We find that hub seaports advance faster than smaller seaports. Road-rail transport constantly showcases high efficiency. Hinterland transport’s efficiencies under environment priority strategy show a weak positive correlation with balanced strategy, and a moderate negative correlation with economy priority strategy. Efficiency improvements in road and road-rail transport can be achieved through enhanced management, while technological innovation is key for road-inland waterway transport. The models and outcomes provide valuable insights for developing sustainable inland transport policies balancing economic growth and emission reduction in regional seaports.

Spatio-temporal heterogeneity and scenario prediction of influencing factors of transportation carbon emissions in the Yangtze River Economic Belt, China

Abstract Reducing carbon emissions in the transportation sector is a crucial aspect of China achieving its carbon peak and carbon neutrality goals. This study investigates the spatiotemporal differentiation characteristics of carbon emissions from transportation in the Yangtze River Economic Belt. Using the Geographically and Temporally Weighted Regression(GTWR) model to reveal the spatio-temporal heterogeneity of factors influencing transportation carbon emissions. Additionally, the Support Vector Regression(SVR) is trained to predict the carbon emissions reduction potential of transportation under different scenarios. The results showed that: From 2000 to 2021, the transportation emissions of the Yangtze River economic belt showed an overall upward trend. The high carbon emission regions are Jiangsu Province, Shanghai, Zhejiang Province and Hubei Province, and the emission center is located in Hubei Province. The total population, urbanization rate, per capita GDP, carbon emission intensity, passenger turnover volume, and civilian vehicle ownership all have a positive effect on transportation carbon emissions, while energy structure has a negative impact. Moreover, the influence of each factor exhibits significant spatial heterogeneity. Under three scenarios: baseline, low-carbon scenario I, and low-carbon scenario II, transportation carbon emissions in the Yangtze River Economic Belt are projected to peak by 2030. With the application of clean energy and a reduction in population size, low carbon scenario II demonstrates greater potential for carbon emission reduction, with a projected value of 88.552 million tons by 2032.

Toward high-integrity forest carbon market of ethnic minority groups in Dak Lak province, Vietnam

Forest carbon markets have demonstrated numerous benefits across economic, social, and environmental dimensions, while also advancing sustainable development goals. This study examines the primary policy mechanisms and conditions related to the development of high-integrity forest carbon markets in Dak Lak province, Vietnam. Utilizing a combination of SWOT analysis and the DPSIR framework, the study provides a comprehensive evaluation of the opportunities, challenges, driving forces, pressures, potential impacts, and responses associated with developing these markets. The Gold Standard method was also employed to estimate the potential contribution to carbon emission reductions through the new forest planting programs in the province. Data analysis from 202 households and in-depth interviews with fifteen experts revealed that local residents have limited information about the forest carbon market. While forest management officials at various levels are aware of the market, there is a lack of specific guidance, limited participation in training sessions and workshops, and insufficient instructional materials. Dak Lak holds significant potential for carbon emission reductions, with an estimated average forest carbon storage capacity of 7.5 tCO2/ha/year for an afforestation/reforestation (A/R) carbon project. This initiative is projected to contribute approximately $753,972 annually to the province's GRDP and generate 280 jobs for local communities. However, the technical and financial resources are challenging in the province. The study identifies critical issues and proposes appropriate solutions to support Dak Lak in developing high-integrity forest carbon markets in alignment with the national roadmap, ultimately contributing to the achievement of sustainable development goals.

Progress in Corrosion Protection Research for Supercritical CO2 Transportation Pipelines

Carbon Capture, Utilization, and Storage (CCUS) technology is an emergent field with the potential for substantial CO2 emissions reduction, enabling low-carbon utilization of fossil fuels. It is widely regarded as a critical technology for combating global climate change and controlling greenhouse gas emissions. According to recent studies, China has identified CCUS as a key emissions reduction technology in climate change response and carbon neutrality objectives. Within this framework, supercritical CO2 (SC-CO2) transport pipelines are an essential means for efficient and safe transportation of CO2. Corrosion protection of pipelines enhances the efficiency and safety of CCUS technology and supports broader implementation and application. This paper reviews the current research on corrosion protection for SC-CO2 transport pipelines, discusses effect factors, compares various corrosion protection strategies, and analyzes the challenges in corrosion protection of SC-CO2 transport pipelines. It concludes with a perspective on future research and development directions in this field. This paper is dedicated to providing new research strategies for pipeline corrosion protection in CCUS technology in the future, and providing technical support for pipeline corrosion protection in CCUS industrial applications.

Towards a sustainable thermodynamic optimization solution for preparing unburned low-carbon bricks from low-activity tailings

Basalt tailings, as an important type of solid waste in the mining industry and quarries, are mainly stacked in the open air or buried, causing huge potential harm to the environment and society. In this work, we propose a sustainable and promising utilization method for such low alkali activated tailings. A thermodynamic optimization solution and a design model for unburned low-carbon bricks composed entirely of solid waste were established, and the macro-microscopic mechanisms of hydrate formation and durability were comprehensively analyzed. Firstly, the thermodynamic reaction kinetics of the full chemical composition of basalt tailings modulated by fly ash were used to investigate the effects of different reaction material ratios on hydration products. Then, a new optimization design method of chemical thermodynamics model of alkali excitation was proposed. Further, the hydration mechanism of geopolymer was qualitatively and quantitatively analyzed via test of mechanics, XRD, FTIR, SEM and AFM. The calculation results were very consistent with experimental research, and the basalt-based fly ash-modulated geopolymer brick through optimization met the requirements of durability, especially from the viewpoint of excellent high-temperature resistance. Finally, the life cycle assessment (LCA) method was adopted to analyze the carbon emission reduction potential of current eco-friendly bricks. The carbon emissions were approximately 15.6 % of that of sintered shale hollow bricks and 19.4 % of that of aerated concrete building blocks. Thermodynamic optimization design of alkali activated low-activity tailings unburned bricks technology is one-stone-for-two-birds strategy, which can effectively optimize the process of making bricks from tailings.

Ultrawhite and ultrablack asymmetric coatings for radiative cooling and solar heating

Passive daytime radiative cooling, a zero-energy and zero‑carbon cooling technology, has significant potential to substantially reduce reliance on compression-based cooling systems, combat the urban heat island effect, and mitigate global warming. However, current radiative cooling materials either exhibit low efficiency or are susceptible to overcooling, resulting in cooling penalties on winter days. In this work, we designed and fabricated the ultrawhite and ultrablack asymmetric coatings. The top-layer, designed for efficient radiative cooling, consists of a porous polymethyl methacrylate and hollow silica microspheres composite. The underlayer, tailored for solar heating, is composed of a carbon nanotubes and carbon black composite. The cooling side with an exceptional solar reflectivity of 0.98 and a mid-infrared emissivity of 0.97 achieves a comparable daytime subambient cooling of 7.6 °C, with a theoretical net cooling power of 98.8 W/m2. Conversely, the heating side with a solar absorptivity of 0.96, a ultra-high visible light absorptivity of 0.985, and a mid-infrared emissivity of 0.97, results in a daytime above-ambient heating of 12.8 °C, corresponding to a theoretical net heating power of 745 W/m2. Promisingly, our ultrawhite and ultrablack asymmetric coatings hold the promise of addressing the long-standing challenge of all-season temperature regulation, offering significant potential for electricity savings and CO2 emission reduction.

Analysis of the Potential Carbon Emission Reduction Through Interaction Between New Energy Vehicles and Smart Grids

Abstract: This paper analyzes the potential for carbon emission reduction through the interaction between new energy vehicles and smart grids, discussing how the optimization of energy efficiency and balancing of grid loads can be achieved through Vehicle-to-Grid (V2G) technology. The interaction between new energy vehicles and smart grids can enhance energy utilization efficiency, optimize grid management, and reduce reliance on fossil fuels by leveraging renewable energy sources, thereby achieving the goal of carbon emission reduction. However, this process faces multiple challenges including technological integration, cost-effectiveness, policy support, and societal acceptance. The paper proposes a series of strategic recommendations, including promoting technological standardization, enhancing policy and economic incentives, and increasing public awareness and participation, to support the effective interaction between new energy vehicles and smart grids, and to achieve long-term carbon emission reduction goals.

Considering Carbon–Hydrogen Coupled Integrated Energy Systems: A Pathway to Sustainable Energy Transition in China Under Uncertainty

The low-carbon construction of integrated energy systems is a crucial path to achieving dual carbon goals, with the power-generation side having the greatest potential for emissions reduction and the most direct means of reduction, which is a current research focus. However, existing studies lack the precise modeling of carbon capture devices and the cascaded utilization of hydrogen energy. Therefore, this paper establishes a carbon capture power plant model based on a comprehensive, flexible operational mode and a coupled model of a two-stage P2G (Power-to-Gas) device, exploring the “energy time-shift” characteristics of the coupled system. IGDT (Information Gap Decision Theory) is used to discuss the impact of uncertainties on the power generation side system. The results show that by promoting the consumption of clean energy and utilizing the high energy efficiency of hydrogen while reducing reliance on fossil fuels, the proposed system not only meets current energy demands but also achieves a more efficient emission reduction, laying a solid foundation for a sustainable future. By considering the impact of uncertainties, the system ensures resilience and adaptability under fluctuating renewable energy supply conditions, making a significant contribution to the field of sustainable energy transition.

Can green buildings reduce carbon dioxide emissions?

Green buildings are a pivotal strategy for realizing the low-carbon evolution within the construction industry. However, the emission reduction effect of green buildings remains unexplored. This study utilizes prefecture-level data from green building projects in Jiangsu Province, China, from 2008 to 2019, to systematically analyze the nonlinear effects, heterogeneous impacts, and mechanisms of influence that green buildings have on carbon dioxide (CO2) emissions. The research findings are as follows: first, during the early stages of green building development, when the scale of green buildings is relatively small, green buildings lead to an increase in CO2 emissions. However, as the scale of green buildings expands, they can exhibit a significant effect on decreasing CO2 emissions. Second, green buildings have heterogeneous impacts on CO2 emissions: lower-rated green buildings (one or two-star) have an increasing impact on CO2 emissions, while the emission reduction effect of green buildings mainly comes from higher-rated green buildings (three-star). These high-rated green buildings substantially affect the advancement of low-carbon technologies, playing an essential role in achieving emission reduction. Third, the mechanisms through which green buildings influence CO2 emissions are identified: on the one hand, green buildings provide a technical effect that decreases CO2 emissions; on the other hand, by promoting the growth of the construction industry, green buildings would cause an increase in CO2 emissions. Lastly, this study proposes relevant policy implications centered around leveraging the emission reduction potential of green buildings.

A novel energy-saving and emission-reduction strategy based on facile preparation of thermal insulation coatings doped with modified vacuum ceramic microbeads for concrete protection

The development of thermal insulation protective coatings suitable for constructions and buildings offers a multifaceted approach: it substantially reduces indoor temperatures, enhances residential comfort, decreases air conditioning energy consumption, and conserves energy. Additionally, these coatings provide robust resistance against corrosive substances, thereby significantly prolonging the service life of concrete. In this work, the modification of vacuum ceramic microbeads (VCM) through the polymerization of catechol and hexamethylene diamine to form poly(catecholamine) (PCA) was investigated by FT-IR, XRD, and TEM analysis. Increased levels of incorporation of VCM@PCA further decreased thermal conductivity and increased surface hydrophobicity, while excessive incorporation detrimentally affected the coating's mechanical properties. PDMS/VCM@PCA coating demonstrated exceptional thermal insulation performance, reducing coating temperature by 15.9 °C under simulated sunlight exposure, and in outdoor experiments, the interior temperature of the simulated house with this coating was 4.2 °C lower than the external temperature, highlighting its potential for energy conservation, emission reduction, and building temperature regulation. Additionally, PDMS/VCM@PCA coating provided excellent protection for concrete structures, significantly enhancing abrasion resistance. It also improved the interfacial adhesion between the organic layer and concrete under dry, wet, and 10% NaCl immersion conditions. The addition of VCM@PCA further enhanced resistance to chloride ion penetration, effectively reducing chloride ingress. This thermal insulation protective coating presents a novel strategy for energy conservation, emission reduction, and sustainable development in the civil construction industry.

Anaerobic digestion of dairy cow and goat manure: Comparative assessment of biodegradability and greenhouse gas mitigation

This study evaluated the anaerobic digestion (AD) of dairy cow and goat manure from dairy farming operations. The physicochemical characteristics, biodegradability and greenhouse gas emissions (GHG) reduction potential were assessed. Dairy goat manure exhibited higher volatile solids (16 % vs. 10 %) and 34 % greater chemical oxygen demand content (COD) compared to cow manure, indicating better suitability for AD. However, biochemical methane potential tests revealed higher methane yields from cow manure (81 % biodegradability) compared to goat manure (26 % biodegradability), attributed to slower hydrolysis rates and recalcitrant composition of goat manure. Both manures displayed suboptimal carbon-to-nitrogen ratios (<20:1) and excessive levels of mineral nutrients such as calcium. The ammonia–nitrogen and volatile fatty acid levels remained below threshold limits throughout the anaerobic digestion process, indicating no significant accumulation or inhibition. Recovering biogas through AD showed potential GHG reductions of 64 % (2.21 t CO2-eq/cow·year) and 69 % (0.27 t CO2-eq/goat·year) compared to conventional manure management practices. While pretreatment and co-digestion could enhance biogas production, further research is needed to optimise these strategies for efficient resource recovery and environmental sustainability in dairy farming operations.Abbreviations: AD, anaerobic digestion; AWMS, animal waste management systems; BMP, biochemical methane potential; CHNS, carbon, hydrogen, nitrogen, and sulphur; C/N, carbon-to-nitrogen, COD, chemical oxygen demand; GC-FID, gas chromatography-flame ionisation detection; GHG, greenhouse gas; GWPM, global warming potential of methane; He, helium; ICP-MS, inductively coupled plasma mass spectrometry; I/S, inoculum-to-substrate ratio; IPCC, International Panel on Climate Change; NH3-N, ammonia–nitrogen; SD, standard deviation; TBMP, theoretical biochemical methane potential; TN, total nitrogen; TS, total solids; VFAs, volatile fatty acids; VS, volatile solids.

Spatiotemporal prediction of greenhouse gas emissions from rubber wood industry, taking Hainan as the case

The rubber wood furniture industry chain, including planting and manufacturing subsystems, emits significant greenhouse gases (GHGs), meanwhile, has huge carbon emission reduction potential. However, quite few studies have taken the whole industry chain GHGs into consideration, especially assessing and predicting those from rubber tree planting to furniture manufacturing. We took the rubber wood furniture of Hainan province as the case, explored its whole life cycle GHGs from cradle-to-gate and predicted the potential GHGs from 2031 to 2062. This study is fully based on field survey and sampling data, including that of the rubber tree planting (40-year cycle) and furniture manufacturing. The results reveal: (1) Whole industry chain of rubber wood furniture emits 3.27 × 106 kgCO2-eq GHGs per 20,000 t rubber logs consuming, where the planting accounts the most (88.20%). Transport and electricity consumption are the main GHGs sources of planting and manufacturing subsystems respectively; (2) The whole life-cycle GHGs of rubber wood furniture in 2023 of Hainan is 2.07 × 107 kgCO2-eq, which mainly come from Danzhou (24.74%), Haikou (19.55%), and Qiongzhong (15.79%); (3) The total GHGs from the rubber wood furniture industry in Hainan from 2031 to 2062 are 210 MtCO2-eq and 129 MtCO2-eq respectively, without or with felling restriction. The changes of GHGs from 2051 to 2062 are caused by the regional center shift of planting gravity; (4) Improving energy use efficiency and optimizing the location of furniture factories would reduce GHGs. This study can provide empirical support for the low carbon sustainable transformation of the rubber wood furniture industry worldwide.

Optimized Resource Allocation for Sustainable Development in Beijing: Integrating Water, Land, Energy, and Carbon Nexus

Chinese megacities face significant challenges in reducing carbon emissions while balancing economic growth and social welfare. This study constructs an innovative multi-objective optimization model, the SD-NSGA-III model, integrated with a System Dynamics (SD) model and using the Non-dominated Sorting Genetic Algorithm III (NSGA-III) to optimize resource allocation in Beijing. The model targets environmental, economic, and social goals by establishing a water–land–energy–carbon (WLEC) nexus for analyzing resource allocation strategies and carbon reduction pathways under various constraints. Scenario simulations under the efficiency-oriented scenario indicated a potential reduction in energy carbon emissions of 81.4% by 2030. The fairness-oriented scenario revealed significant trade-offs between equity and emission reductions, emphasizing the need for balanced strategies. Introducing constraints on resources and economic growth significantly reduced median energy carbon emissions to 80 million tons by 2030. These findings demonstrate the effectiveness of the SD-NSGA-III model in providing actionable strategies for achieving carbon neutrality and sustainable development in cities.