Life cycle assessment of HFC-134a production by calcium carbide acetylene route in China

HFC-134a is a widely used environment-friendly refrigerant. At present, China is the largest producer of HFC-134a in the world. The production of HFC-134a in China mainly adopts the calcium carbide acetylene route. However, the production route has high resource and energy consumption and large waste emission, and few of the studies addressed on the environmental performance of its production process. This study quantified the environmental performance of HFC-134a production by calcium carbide route via carrying out a life cycle assessment (LCA) using the CML 2001 method. And uncertainty analysis by Monte-Carlo simulation was also carried out. The results showed that electricity had the most impact on the environment, followed by steam, hydrogen fluoride and chlorine, and the impact of direct CO₂ emissions in calcium carbide production stage on the global warming effect also could not be ignored. Therefore, the clean energy (e.g., wind, solar, biomass, and natural gas) was used to replace coal-based electricity and coal-fired steam in this study, showing considerable environmental benefits. At the same time, the use of advanced production technologies could also improve environmental benefits, and the environmental impact of the global warming category could be reduced by 4.1% via using CO₂ capture and purification technology. The Chinese database of HFC-134a production established in this study provides convenience for the relevant study of scholars. For the production of HFC-134a, this study helps to better identify the specific environmental hotspots and proposes useful ways to improve the environmental benefits.     

Life cycle assessment of oxygen-18 production using cryogenic oxygen distillation

In this study, life cycle assessment of oxygen-18 by using cryogenic distillation of oxygen is performed using SimaPro 8.3 software. Life cycle assessment is performed to understand the environmental profile and hotspots of this process in order to be used in design and development. Simulation of oxygen-18 process is executed by Hysys software, and the required inputs and outputs for inventory of life cycle were acquired. By doing life cycle assessment and considering achieved results after characterization and normalization of inventory data it has been investigated that in the majority of environmental impacts electricity consumption has a huge contribution relative to other parts of the system like liquefied oxygen production from air separation unit, required facilities for air separation and oxygen-18 units, and needed transportation. Also, among 17 impact categories investigated in ReCiPe impact assessment method, fossil depletion, climate change (human health), particulate matter formation, climate change (ecosystem), human toxicity, and metal depletion have the most contribution in entire environmental loads respectively. Furthermore, sensitivity analysis showed that changing life cycle impact assessment method from ReCiPe to IMPACT 2002 + has no significant effect on acquired results and results are confident. In addition, assumption of market for depleted oxygen from heavy isotopes which is withdrawn from top of distillation columns showed some positive effects compared to first case and environmental impacts resulted from liquefied oxygen production (feed) reduced but because of huge contribution of electricity consumption compared to other sections, this positive effect has no remarkable influence on entire environmental loads of product system.     

Comparative analysis of the life cycle impact assessment of available cement inventories in the EU

Life cycle impact assessment (LCIA) is one of basic steps in life cycle assessment methodology (LCA). This paper presents a comparative study of the LCIA of different life cycle inventories (LCI) for EU cements. The analysis unit used is the manufacture of 1 kg of cement, from “cradle to gate”. The impact categories considered are those resulting from the manufacture of cement and include greenhouse effects, acidification, eutrophication and summer and winter smog, amongst others.The results of the study highlighted some inconsistencies in existing inventories. As for the LCIA, the main environmental interventions related to cement manufacture were classified and characterised and their effect on different impact categories analysed. Differences observed in evaluation of the impact of cement type were essentially related to their clinker content.     

Life cycle assessment of functional materials and devices: Opportunities,challenges, and current and future trends

Functional ceramics such as piezoelectrics, thermoelectrics, magnetic materials, ionic conductors, and semiconductors are opening new frontiers that underpin numerous aspects of modern life. This widespread usage comes with a responsibility to understand what impact their mass production has on the environment. Life-cycle assessment (LCA) is a tool employed for the identification of sustainable materials pathways through the consideration of environmental burdens of materials both during fabrication and as a final product. Although the LCA technique has been widely used for the evaluation of environmental impacts in numerous product supply chains, its application for environmental profiling of functional ceramics is now gaining attention. This paper presents a review of current developments in LCA, including existing and emerging applications with emphasis on the development and fabrication of functional materials and devices (FM&D). Selected published works on LCA of functional ceramics are discussed, highlighting the importance of adopting LCA at the design stage and/or at laboratory stage before expensive investments and resources are committed. Drawing from the extant literature, we show that the integration of environmental and sustainability principles into the overall process of FM&D manufacturing, in a way that anticipates foreseeable harmful consequences while identifying opportunities for improvement, can aid the timely communications of key findings to functional materials developers. This guides the orientation of research, development and deployment, and provides insights toward the prioritization of research activities while potentially averting unintended consequences. It is intended that the review presented will encourage the materials science community to engage with LCA to address important materials design, substitution, and optimization needs.     

LCA tool for the environmental evaluation of potable water production

Environmental impact assessment will soon become a compulsory phase in future potable water production projects, especially when alternative treatment processes such as desalination are considered. An impact assessment tool is therefore developed for the environmental evaluation of potable water production. The evaluation method used is the life cycle assessment (LCA) method. The quick and easy assessment of energetic and environmental performances contributes to determine the weak points of potable water production processes or the best suited treatment in a specific context. Studies of some potable water supply scenarios (groundwater treatment, ultrafiltration, nanofiltration, seawater reverse osmosis and thermal distillation associated to water transfer) are presented in order to illustrate the environmental information drawn from this tool. The main source of impacts is shown to be electricity production for plant operation. Improvement levers are presented for impact reduction and for the objective comparison between alternative and conventional water treatment processes.     

退役锂离子电池湿法回收生命周期和经济评价

锂离子电池（LIBs）具有能量密度高、输出功率大等优点被广泛应用,随之产生了大量退役LIBs。近年来,退役LIBs回收再利用逐渐受到了人们的关注,但目前回收体系尚不完善,存在发展动力和科学技术等方面的问题。从生命周期评价（LCA）和经济性评价两方面对典型的盐酸、硫酸-双氧水和电化学浸出3种回收方法进行分析讨论。使用SimaPro 9软件对回收过程进行生命周期评价,得到全球变暖潜能值、非生物资源耗竭潜能值和资源消耗量等,结果表明酸用量和能量消耗为主要的环境影响因素;并对回收再利用过程（包括预处理、浸出、再制备）进行经济性分析,得到相应的收益情况。结果表明,目前回收成本较高,整体呈现亏损状态。基于此,提出了相应的优化建议。     

Incorporating environmental impacts and regulations in a holistic supply chains modeling: An LCA approach

Corporate approaches to improve environmental performance cannot be undertaken in isolation, so a concerted effort along the supply chain (SC) entities is needed which poses another important challenge to managers. This work addresses the optimization of SC planning and design considering economical and environmental issues. The strategic decisions considered in the model are facility location, processing technology selection and production–distribution planning. A life cycle assessment (LCA) approach is envisaged to incorporate the environmental aspects of the model. IMPACT 2002+ methodology is selected to perform the impact assessment within the SC thus providing a feasible implementation of a combined midpoint–endpoint evaluation. The proposed approach reduces the value-subjectivity inherent to the assignment of weights in the calculation of an overall environmental impact by considering endpoint damage categories as objective function. Additionally, the model performs an impact mapping along the comprising SC nodes and activities. Such mapping allows to focus financial efforts to reduce environmental burdens to the most promising subjects. Furthermore, consideration of CO₂ trading scheme and temporal distribution of environmental interventions are also included with the intention of providing a tool that may be utilized to evaluate current regulatory policies or pursue more effective ones. The mathematical formulation of this problem becomes a multi-objective MILP (moMILP). Criteria selected for the objective function are damage categories impacts, overall impact factor and net present value (NPV). Main advantages of this model are highlighted through a realistic case study of maleic anhydride SC production and distribution network.     

生物质型煤与褐煤的生命周期评价对比研究

为了研究生物质型煤对环境的影响和能耗情况,利用生命周期评价方法,与褐煤进行对比评价,从型煤与褐煤的生产到燃烧进行全面分析。结果表明,生物质型煤生命周期的环境负荷指数是0.30,褐煤的潜在环境影响负荷指数为0.48,生物质型煤的环境影响明显低于褐煤;环境影响类型主要是全球变暖,主要影响因子是CO2;生命周期各阶段的环境排放量主要集中于燃烧使用阶段,因此,降低燃烧使用阶段的环境影响是生物质型煤技术改进的重要途径。     

农林废弃物气化合成混合醇生命周期环境影响分析

生物质热化学气化合成混合醇技术具有工艺相对简单、产物的能源化工应用广泛等优点,为准确评价该技术的资源能源消耗、辨析合成燃料的环境性能,基于生命周期分析框架和ReCiPe2016中点评价方法,对农林废弃玉米秸秆和木屑经气化、催化合成混合醇工艺的清单和9种环境影响类型开展分析和比较。结果表明：农林业阶段均为环境影响的主要阶段,秸秆混合醇生命周期影响高于木屑混合醇。前者的臭氧层耗竭潜值、海洋和淡水富营养化潜值、全球变暖潜值均为木屑混合醇相应结果的9倍以上。废弃物原料高碳含量和高混合醇收率有利于降低资源消耗和环境影响。与石化汽油相比,秸秆和木屑混合醇的全球变暖和化石能源消耗潜值均降低40%以上。     

An introduction to life cycle assessment with hands-on experiments for biodiesel production and use

This paper describes a hands-on project that introduces first year engineering students to life cycle assessment (LCA) through the comparison of the environmental impact of the production and use of three diesel fuels: petroleum diesel, biodiesel from new vegetable oil, and biodiesel from waste vegetable oil. The purpose of this LCA project was to incorporate life cycle thinking into the engineering design process, to apply the four main steps of LCA (definition and scope, inventory analysis, impact assessment and improvement assessment), and to explore some of the challenges associated with each step. The inventory for biodiesel production (from both new and waste vegetable oils) was based on measurements obtained by the students in laboratory experiments. The fossil diesel production inventory was obtained from the SimaPro^® database. The inventory for the use of all three fuels was obtained from measurements taken during combustion of the fuels in a generator. A cradle-to-grave life cycle analysis was then conducted using SimaPro^® for each fuel. The assessment of learning outcomes indicates a significant increase in conceptual understanding of the four stages of life cycle assessment, and an average gain of over 55% in overall knowledge of life cycle assessment.     

能源和化工系统的全生命周期评价和可持续性研究

在资源和能源日趋紧缺的背景下,开拓替代能源和新的化工产品技术路线势在必行。然而,目前对各种新技术方案的基础数据和系统分析比较薄弱,对产业布局和生态环境的长期影响有待深入研究。对近年来研究资源/能源化工复杂系统的建模、模拟、结构优化和系统集成问题的进展进行综述,运用过程系统投入产出分析的理论和方法,建立化工产品技术路线的全生命周期分析模型与集成的框架平台,研究资源、能源、技术、经济、环境等多因素综合优化评价问题。以煤气化合成气衍生的煤化工系统为基础案例,专门论述了在产品路线规划和过程合成中,集成优化、全生命周期评价和可持续性的研究进展。目标在于推进"技术-经济-环境-产业发展"多属性、多目标、多尺度系统集成的基础理论研究和技术创新。     

Incorporating life cycle assessment and ecodesign tools for green chemical engineering: A case study of competences and learning outcomes assessment

Chemical engineers assume a broad range of roles in industry, spanning the development of new process designs, the maintenance and optimization of complex systems, and the production of intermediate materials, final products and new technologies. The technical aptitude that enables chemical engineers to fulfill these various roles along the value chain makes them compelling participants in the environmental assessment of the product in question. Therefore, the introduction of life cycle assessment (LCA) and ecodesign concepts into the chemical engineering curriculum is essential to help these future professionals to face design problems with a holistic view of the technical, economic, social and environmental impacts of their solutions. The teaching of these and other disciplines by means of student-centered methods, based on a holistic structure, have demonstrated better teamwork and communication skills. For that reason, this paper proposes a Micro (Assess-Analyze-Act) (M-3A) model of assessment mainly focused on closing the loop of the learning activities. This model has been applied to an ecodesign case study of the “University master’s Degree in chemical engineering” of the University of Cantabria/University of the Basque Country, with positive feedback of the students. They felt that the approach has allowed them to utilize their analytical skills in quantifying a situation before applying other subjective measures, and that the public discussion of the results was a satisfactory element for improving their communication skills. Moreover, the students found that the workload was nicely adjusted, highlighting the acquisition of 4 competences preferentially: teamwork, creativity; relevance of environmental issues and initiative and entrepreneurship. Finally, the students suggest that the application of this methodology into their degree could motivate future students improving their performance.     

生命周期评价在塑料研究中的应用进展

简要介绍了生命周期评价(LCA)的起源及定义,分析了国内外塑料生命周期的评价实例,指出了LCA在应用中的局限性,提出我国生命周期评价与国外的差距,建议建立塑料行业数据库。     

Life cycle assessment and economic analysis of HFC-134a production from natural gas compared with oil-based and coal-based production

China is the largest producer and consumer of HFC-134a (1,1,1,2-tetrafluoroethane) in the world. Coal-based route is mainly adopted to produce HFC-134a, which suffers from large waste and CO₂ emissions. Natural gas is a low-carbon and clean energy resource, and no research has been found on the environment and economy of producing HFC-134a from natural gas. In this study, CML 2001 method was used to carry out the life cycle assessment of natural gas (partial oxidation)-based and natural gas (plasma cracking)-based routes (abbreviated as gas(O)-based and gas(P)-based routes, respectively), and their environmental performances were compared with coal-based and oil-based routes. Meanwhile, considering that China is vigorously promoting the transformation of energy structure, and the application of electric heating equipment to replace fossil-based heating equipment in industrial field, which has a great impact on the environmental performance of the production processes, the authors conducted a scenario analysis. The results showed that the gas(O)-based route had the most favourable environmental benefits. However, the gas(P)-based route had the highest potential for reducing environmental burdens, and its environmental benefit was the most favourable in scenario 2050. Additionally, the economic performance of the gas(P)-based route was significantly better than that of gas(O)-based and coal-based routes.     

Design‐based life cycle assessment of hazardous air pollutant control options at pulp and paper mills: a comparison of thermal oxidation to photocatalytic oxidation and biofiltration

BACKGROUND: The forest products industry produces valuable industrial chemicals, wood products, and consumer goods, but is also responsible for the emission of significant quantities of hazardous air pollutants. Although many air pollution control options are available, little is known about the overall environmental impacts of implementing each option. Therefore, a life cycle assessment (LCA) was conducted to compare energy and raw material inputs, air emissions, and environmental impacts associated with construction and operation of two air pollution control systems: regenerative thermal oxidation (RTO) with wet scrubbing and photocatalytic oxidation (PCO) with biofiltration. RESULTS: LCA results indicated that environmental impacts to resource depletion, photochemical oxidant formation, and acidification were 20% higher for the use of a RTO‐scrubber than for the PCO‐biofilter. In addition, at least 25% of the RTO impacts were due to infrastructure requirements. However, the PCO‐biofilter system was responsible for more environmental impact in categories of global warming and human toxicity, because of the packing materials required and the electricity use for the PCO reactor. CONCLUSIONS: The PCO‐biofilter system could be a promising, environmentally‐friendly alternative to traditional RTO devices, provided that this system is modified to decrease resource and energy demands. Copyright © 2008 Society of Chemical Industry     

Long-term fate of PVC products and their additives in landfills

The development of sustainable products requires not only the consideration of production processes. Rather, strategies and concepts for the end-of-life management of post-consumer products play an important role for their legal compliance, public acceptance and commercial competitiveness as well. With respect to the waste management options for polyvinyl chloride (PVC) products, the currently prevalent disposal in landfills was among the subjects of debate about environmental issues. A material and substance flow analysis was conducted to estimate the quantitative relevance of PVC products and their constituents in municipal solid waste. Landfill simulation assays demonstrated the long-term behaviour of PVC products and the fate of additives under landfill conditions. The methods of an integrated assessment and possible approaches towards life cycle management are discussed.