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The battery electric vehicle (BEV) industry, commanding over half of the global market share in China, has garnered significant attention in response to escalating concerns about climate change. NCM (LiNi x Co y Mn z O 2) batteries, prized for their high energy density, are pivotal in this industry. However, their production relies on critical metals, posing environmental challenges. Recycling processes aim to address this issue by recovering critical metals from end-of-life batteries. The industry is updating from NCM 111 to NCM 811 batteries to enhance energy density and reduce costs, but the key factors influencing the material flows and environmental impacts remain uncertain. This paper aims to identify the key factors contributing to the potential differences in material flows and environmental impacts introduced by the NCM battery upgrading in China. Following the new energy vehicle sales projections in China until 2035, a dynamic material flow analysis was employed to calculate material demands, recovered amounts, and substitution rates for various upgrading scenarios. The study reveals that the majority of retired batteries until 2035 were sold between 2022 and 2029. Material substitution rates prove to be more sensitive to the upgrading scenario than the lifetime and growth rate of BEVs. Faster NCM 811 penetration results in over 2.5 times more saved cobalt demand compared to additional nickel demand. A life cycle assessment of NCM batteries reveals a 39% lower global warming impact for NCM 811 compared to NCM 111, highlighting environmental benefits from increased energy density and reduced cobalt consumption. The energy density improvement contributed 85%, while the alteration in material composition contributed 15% to the global warming reduction in NCM 811. Recycling emerges as a crucial strategy in mitigating environmental impacts across all categories, particularly addressing eutrophication, previously deemed challenging due to the difficulty in recovering Li 2 CO 3. [ABSTRACT FROM AUTHOR]

At present, the energy and environmental crisis is increasingly prominent, and how to solve the global energy and environmental problems is one of the challenges facing the world today. China is a major producer and consumer of organosilicon, so it is necessary to explore the stage of high energy consumption and high pollution in the organosilicon industrial chain. In 2022, the proportion of submerged arc furnaces of 25000 kVA and higher in China reached 40%. Further expansion of these furnaces in the future is inevitable. However, research on the life cycle assessment of organosilicon manufactured using large-capacity submerged arc furnaces is still blank.Therefore,in this paper, the life cycle assessment method is used to evaluate the synthesis process of chemical grade silicon-organosilicon monomer prepared by large capacity (33000 kVA) submerged arc furnace, and the dominant process in various environmental impacts is defined.At the same time, the measures to improve the production process of organosilicon monomer were put forward. In the production process of 1000 kg organosilicon monomer, global warming potential (GWP) contributed the most (73.43%) to the comprehensive environmental impact, followed by chronic public health impact (HTI, 10.55%). Energy consumption (EN) accounted for 8.50%, while resource consumption (RU) accounted for 7.43%. The contributions of other environmental factors were relatively small (0.09%).The energy consumption and environmental pollution in the production of organosilicon monomer can be reduced by strictly controlling the quality of raw materials into the furnace, using heat pump technology in the distillation unit, and comprehensively utilizing the heat of reaction by-products and steam condensate. [Display omitted] • This study is the first one in China to conduct LCA for the preparation of chemical grade silicon-organosilicon monomer synthesis process in 33000 kVA submerged arc furnace. It provides the best improvement suggestions for reducing the environmental load of the product life cycle process and achieving cleaner production. • In response to the national development policy of large-scale submerged arc furnace, the dominant process of preparing organosilicon monomer based on 33000 kva submerged arc furnace in various environmental impacts was clarified. • The main technical improvement directions are: Strictly control the quality of raw materials for submerged arc furnace; Strictly control the sulfur content and nitrogen content of carbonaceous reductant, and adopt the most suitable flue gas treatment technology route; Smelt with large submerged arc furnace; Use heat pump technology for distillation unit; Optimize the monomer synthesis device. [ABSTRACT FROM AUTHOR]

Abstract In the context of China's severe energy and environmental problems, as an alternative vehicle fuel bioethanol is a promising choice because its theoretically renewable and carbon neutral. To guarantee grain security, China is developing non-grain fuel ethanol. Based on a life cycle assessment (LCA), this paper assesses the uncertainty of energy efficiency and environmental performance in the development of cassava ethanol of 1.5-generation bioethanol whose raw materials are non-staple crops. The results show that cassava ethanol is a good alternative vehicle fuel from the view of energy efficiency. From an environment perspective, global warming potential and photochemical ozone formation potential of cassava ethanol are better than gasoline, but acidification potential and respiratory inorganics inferior. The Monte Carlo simulation reveals cassava ethanol is feasible compared with gasoline in the case of uncertain variables. Among these uncertain variables, cassava yield, nitrogen fertilizer use, and steam use are the most important variables for energy efficiency and environmental performance of cassava ethanol. Furthermore, this study calculates the potentials for energy savings and emissions reduction with improving key aspects, and gives the suggestions of enhancing the performance of key indicators to promote the development of bioethanol vehicle fuel. Highlights • Cassava ethanol is a good alternative vehicle fuel from the view of energy efficiency. • Cassava ethanol decreases GWP and POFP, but increases AP and RI compared with gasoline. • Cassava yield, nitrogen fertilizer usage and steam usage have the greatest impact on cassava ethanol. • The potentials of energy-saving and emission-reduction are calculated with improving key aspects. [ABSTRACT FROM AUTHOR]

Natural gas is regarded as a cleaner alternative to coal combustion-based power generation (CPG) for urban use. Because of the insufficient natural gas reserve in China, coal-based synthetic natural gas (SNG) has been under rapid development. However, coal-based SNG production process has problems of environmental pollution and emission transfer. This paper uses life cycle assessment to compare the CPG and SNG energy production and usage routes, in order to find a reasonable way to reduce the environmental pollution and production cost. Results show that the CPG route is superior to the SNG route in terms of the haze pollution emissions, greenhouse gases emissions, coal resource consumption and life cycle cost. However, the water consumption of the CPG route is much higher than that of the SNG route. The SNG route is more suitable to adopt in water-deficient areas. [ABSTRACT FROM AUTHOR]

China's growing capacity of bioethanol production renders the conversion of ethanol-to-jet fuel (ETJ) promising. However, ETJ studies are currently scarce in China. This study employed process simulation to model two novel ETJ processes that combined corn cob gasification, syngas-to-ethanol, and ethanol-to-jet fuel. This paper also discussed the other three ETJs, in which ethanol were obtained via direct-fermentation of corn, cassava, and corn cob, respectively. Life cycle assessment (LCA) was performed to evaluate energy consumption and greenhouse gas (GHG) emissions of ETJs in China. The results showed that the ETJ pathway, which included corn cob gasification plus fermentation, showed the least energy consumption and GHG emission, with 370.05 KJ/MJ jet fuel and 31.66 gCO 2 eq/MJ jet fuel, respectively. Sensitivity analysis was performed to identify parameters that had a significant impact on the results, and uncertainty analysis was implemented to check the reliability of the result. Further analysis revealed that cleaner electricity and heat production could effectively reduce the GHG emissions of the energy-intensive ETJs, with the highest reduction of 21.55%. Given that few life cycle assessments of ETJs in China have reported, this study can assist policy-makers to decide the path in which China's sustainable aviation fuel (SAF) should evolve. [Display omitted] • Life cycle analysis for 5 ethanol-to-jet fuels established toward China situation. • The process based on corn-cob-syngas fermentation showed the best carbon reduction. • Optimizing biomass and ethanol conversion could greatly reduce GHG emissions. • Electricity mixes highly impacted on the process based on corn-cob-syngas catalysis. • Life cycle results were mostly sensitive to the displacement allocation method. [ABSTRACT FROM AUTHOR]

Municipal heating by coal contributes considerably to the haze pollution in Chinese cities during cold period, e.g., Beijing 53%. It is widely considered that, as a supplement of natural gas, the use of coal-based synthetic natural gas (SNG) to replace coal for municipal heating is conductive to mitigate the haze pollution in metropolitan areas. Would it still be a good alternative if the whole life cycle of SNG were taken into consideration? In this study, SNG as an alternative for municipal heating is analyzed in comparison with coal. To target cleaner production, life cycle assessment methodology is used to analyze SNG contribution to haze pollutants and greenhouse gases (GHGs) emissions, as well as energy consumption. Compared to coal heating route, SNG heating route could reduce 44% of the haze pollutants emissions from life cycle perspective and up to 98% of the emissions in urban area. Thus, if municipal heating were entirely supplied by natural gas and SNG, there would be 52% less haze pollutants emissions in winter of Beijing. However, this “good” performance is at the cost of transferring haze pollutants emissions from urban areas to SNG-producing regions. It is also at the cost of consuming 90% more coal and emitting 65% more GHGs than the coal heating route from life cycle point of view. To tackle the problems of haze pollutants transfer and the increase of GHGs emissions, the paper suggests implementing ecological compensation and carbon tax policies in the coal-based SNG industry. [ABSTRACT FROM AUTHOR]

China was positioned as the world's largest producer and consumer of ceramic tiles, accounting for 50% of tile production and 40% of tile consumption in the world approximately. Recently, Chinese ceramic industry has increased its focus on environmental issues with the aim of protecting natural resources and reducing pollutant emission. This study evaluated and compared the environmental impacts of ceramic tiles produced by traditional technology and cleaner production technology using life cycle assessment methodology with "cradle to gate" perspective. The results showed that the energy consumptions and emissions from fuel combustion were the hotspots of the environmental impact caused by tile production. The drying and firing processes were the main contributors to the energy consumption at the ceramic production stage. Moreover, the environmental impact reduction potential of different cleaner production technologies was elaborated in this paper. The results proved that applying natural gas as fuel instead of coal (producer gas) caused less damage on human health and ecosystem but more damage on the resource. The dry-milling process has potential to reduce environmental impacts compared with wet-milling process in all midpoint and endpoint indicators. In addition, the sensitivity analysis of input parameters, transportation distance and qualified products rate was conducted to identify the key parameters that have great influence on the results. • Ceramic products from four typical plants in China was analyzed using LCA. • Environmental impact of different fuel scenarios and milling technologies was compared. • Applying the natural gas as fuel instead of coal (producer gas) caused less damage on human health and ecosystem. • Dry-milling process have potential to reduce the environmental impact compared with wet-milling process. • Sensitivity analysis related to input parameter, transport distance and qualified products rate were conducted. [ABSTRACT FROM AUTHOR]