Multifunctional phase change film with high recyclability, adjustable thermal responsiveness, and intrinsic self-healing ability for thermal energy storage

Phase change materials(PCMs) present promising potential for guaranteeing safety in thermal management systems.However,most reported PCMs have a single application in energy storage for thermal management systems,which does not meet the growing demand for multi-functional materials.In this paper,the flexible material and hydrogen-bonding function are innovatively combined to design and prepare a novel multi-functional flexible phase change film(PPL).The 0.2PPL-2 film exhibits solid-solid phase change behavior with energy storage density of 131.8 J/g at the transition temperature of42.1℃,thermal cycling stability(500 cycles),wide-temperature range flexibility(0-60℃) and selfhealing property.Notably,the PPL film can be recycled up to 98.5% by intrinsic remodeling.Moreover,the PPL film can be tailored to the desired colors and configurations and can be cleverly assembled on several thermal management systems at ambient temperature through its flexibility combined with shape-memory properties.More interestingly,the transmittance of PPL will be altered when the ambient temperature changes(60℃),conveying a clear thermal signal.Finally,the thermal energy storage performance of the PPL film is successfully tested by human thermotherapy and electronic device temperature control experiments.The proposed functional integration strategy provides innovative ideas to design PCMs for multifunctionality,and makes significant contributions in green chemistry,highefficiency thermal management,and energy sustainability.

Design Details of Low-Energy and Passive Houses Using Composites from Waste Raw Materials

The article deals with potential use of waste materials in construction industry, specifically use of high density polyethylene （HDPE）. The article is focused in particular on recycled polyethylene application in products designed for construction industry, especially for passive houses. Currently certain building details of passive houses are not perfect or their solution results in higher economic demands related to house purchase and its further use. For the purpose of this thesis details of windows installation in external walls and elimination of thermal bridges in wall footing have been chosen. Products were subject to mathematic modelling of thermal technique and statics. The executed mathematic models documented that products are fully functional and that the suggested product successfully eliminate insufficiencies of some currently applied solutions.

RESOURCE RECOVERY AND MATERIALS FLOW IN THE CITY Zero Waste and Sustainable Consumption as Paradigm in Urban Development

Beyond energy efficiency,there are now urgent challenges around the supply of resources,materials,food and water.After debating energy-efficiency for the last decade,the focus has shifted to include resource and material-efficiency.In this context,urban farming has emerged as a valid urban design strategy in Europe,where food is produced and consumed locally within city boundaries,turning disused sites into productive urban landscapes and community gardens.Agricultural activities allow for effective composting of organic waste,returning nutrients to the soil and improving biodiversity in the urban environment.Urban farming will help to feed the 9 billion by 2050(predicted population growth,UN-Habitat forecast 2009).This paper reports on best practice of urban design principles in regard to materials flow,material recovery,adaptive re-use of building elements and components(‘design for disassembly’;prefabrication of modular building components),and other relevant strategies to implement zero waste by avoiding waste creation,reducing harmful consumption and changing behaviour.The paper touches on two important issues in regard to the rapid depletion of the world’s natural resources:the construction sector and the education of architects and designers.The construction sector:Prefabricated multi-story timber buildings for inner-city living can set new benchmarks for minimizing construction wastage and for sustainable on-site assembly.Today,the construction and demolition(C&D)sector is one of the main producers of waste;it does not engage enough with waste minimization,waste avoidance and recycling.Education and research:It’s still unclear how best to introduce a holistic understanding of these challenges and to better teach practical and affordable solutions to architects,urban designers,industrial designers,and so on.One of the findings of this paper is that embedding‘zero-waste’requires strong industry leadership,new policies and effective education curricula,as well as raising awareness(education)and refocusing research agendas to bring about attitudinal change and the reduction of wasteful consumption.

Impact of recycling improvement on the life cycle of phosphorus

Access to natural resources is increasingly more difficult and more costly, partly due to their economic significance and to continuous increase of their global consumption in the recent years. In the case of phosphorus (P), which is a critical raw material, geological distribution of its primary nonrenewable source (phosphate rock) is concentrated in particular regions leading to high supply risk of this raw material. In Europe (EU-28), where phosphate rock reserves are scarce, import of phosphorus has been the main source of supply. It means that Europe relies highly on the foreign exporters. From decision makers' perspective, recycling of phosphorus was taken into account as one of the possible solutions to decrease the dependence on imports and extraction of reserves. The question, however, is to what extent does the recycling of phosphorus help in reducing the reliance on typical supply resources? Hence, the main objective of this paper is to quantify the dynamic flow of phosphorus and show potential benefits of its recycling in Europe. This article presents a system dynamics model for representation of the element P flow and helps to quantify to what extent the recycled phosphorus could mitigate its criticality. Analysis of the results supports previous studies indicating the high reliance ofEU on P imports, estimating around 96% as the reliance percentage on imports. The results imply that improving P recycling has the potential to decrease the level of P imports to a certain extent, which may reach 79%.

Efficiency of Structural Materials in Sustainable Design

The main aim of this paper is to investigate energy consumptions, CO2 emissions and costs during the production and life cycle of structural materials. The virgin and recycled metals as well as waste minerals such as fly ash, slag in concrete save energy consumption, CO2 emissions and costs. The importance and effectiveness of recycled materials will be statistically evaluated via energy consumption, carbon footprint, ultimate strength and their ratios. Embodied energy to ultimate strength or embodied carbon to ultimate strength ratios may emphasize the effectiveness of a sustainable material. The analyses in this study indicate the utilization of the recycled steel and C50 concrete with 50% fly ash or slag is the most efficient way of using sustainable materials.

A review of cathode and electrolyte recovery from spent lithium-ion batteries: Recent technologies, processes and policies

Recently,lithium-ion batteries(LIBs),due to their superior performance,have been vastly applied in electronic,auto,and other industries,resulting in the generation of an increasing amount of spent LIBs.What’s worse,LIBs contained potentially toxic substances,including heavy metals,toxic and flammable electrolyte containing LiBF_(4),LiClO_(4),and LiPF_(6).Conventional disposal of spent LIBs via landfill or incineration exerts tremendous pressure on the environment.It was necessary to adopt efficient,low-cost,and environmentally friendly approaches to valorizing spent LIBs,which could not only alleviate the shortage of rare resources by recycling valuable ele-ments such as Cu,Li,Mn,Ni,Co,and Al,but also eliminate the pollution of harmful components in batteries and realize the recycling and sustainable industry related to consumer electronics and electric vehicles(EVs).Given this,this paper summarized the recycling technologies of spent LIBs,including pyrometallurgy(melting reduction and roasting methods)and hydrometallurgy(leaching,precipitation,extraction,ion-exchange,elec-trochemical,sol-gel methods),and electrolyte recycling(organic solvent extraction and supercritical extraction methods).Pyrometallurgy technologies had relatively decent metal recovery rates but were associated with high energy consumption and atmospheric emission issues.Hydrometallurgical technologies were more environ-mentally friendly and efficient in recovering spent LIBs,although disposing of the wastewater generated from the process remained a challenge.In addition,the different industrial processes and various countries’related policies of recycling spent LIBs were investigated.In the end,the outlooks and future directions of recycling spent LIBs were proposed.

Experimental study and assessment of thermal energy storage mortar with paraffin/recycled brick powder composite phase change materials

Thermal energy storage recycled powder mortar(TESRM)was developed in this study by incorporating paraffin/recycled brick powder(paraffin/BP)composite phase change materials(PCM).Fourier transform infrared and thermogravimetric analysis results showed that paraffin/BP composite PCM had good chemical and thermal stability.The onset melting temperature and latent heat of the composite PCM were 46.49°C and 30.1 J·g−1.The fresh mortar properties and hardened properties were also investigated in this study.Paraffin/BP composite PCM with replacement ratio of 0%,10%,20%,and 30%by weight of cement were studied.The results showed that the static and dynamic yield stresses of TESRM were 699.4%and 172.9%higher than those of normal mortar,respectively.The addition of paraffin/BP composite PCM had a positive impact on the mechanical properties of mortar at later ages,and could also reduce the dry shrinkage of mortar.The dry shrinkage of TESRM had a maximum reduction about 26.15%at 120 d.The thermal properties of TESRM were better than those of normal mortar.The thermal conductivity of TESRM was 36.3%less than that of normal mortar and the heating test results showed that TESRM had good thermal energy storage performance.

废旧锂离子电池正极材料回收研究进展

随着锂离子电池(lithium-ion batteries,LIBs)在电动汽车、3C电子产品和储能领域的大规模应用和产销量的日益剧增,其退役后带来的金属浪费和环境污染问题也日益突出。有必要大力开发绿色环保、高效低成本的废旧锂离子电池正极材料回收工艺,实现金属资源的周期性利用。回顾了废旧锂离子电池正极材料回收工艺的最新进展。概述了现有的回收工艺,详细介绍了预处理、火法冶金、湿法冶金、生物浸出和直接回收等回收工艺的研究现状。并通过对比分析现有技术存在的问题,综合讨论了各工艺的回收效率、安全性和经济价值。最后,展望了废旧锂离子电池正极材料回收再利用的前景和发展趋势,旨在为直接化、高值化、规模化的废旧锂电池回收再利用研究提供借鉴与参考。

柠檬酸浸出废旧锂离子电池中的镍钴锰

采用柠檬酸+过氧化氢浸出体系从废旧三元锂离子电池正极材料中回收镍、钴、锰,分析了浸出过程中可能发生的反应,分别考察了柠檬酸浓度、过氧化氢质量分数、浸出温度、浸出时间、液固比等因素对正极材料中镍、钴、锰浸出率的影响。在柠檬酸浓度1.5 mol/L、过氧化氢质量分数8%、浸出温度80℃、浸出时间60 min及液固比25 mL/g条件下,金属镍、钴、锰浸出率分别为97.58%、97.35%、96.12%。以乙醇为溶析剂,采用溶析结晶法从浸出液中回收金属,镍、钴、锰结晶率分别为92.34%、93.07%、99.69%。

回料利用对食品工业污泥生物干化的影响

利用热风系统进行食品工业脱水污泥生物干化的污泥作为回料,在相同条件下探究不同比例回料利用对污泥生物干化效果的影响.结果表明,回料:稻草:污泥=1:1:4(质量比)时生物干化效果最好,高温期可维持72h且每日累积温度TD为30.96℃/d,单位水分去除量为287.45g/kg WM,但延长了生物干化周期,使得处理污泥负荷降低.三维荧光光谱分析表明回料利用实验组在生物干化高温期腐殖酸和富里酸类物质增多,TC由生物干化前的243.8~264.2g/kg WM下降至生物干化后的191.7~224.9g/kg WM,回料可增加TC保留量.单位水分去除所产生的CO_(2)排放量为168.7~226.9L CO_(2)/kg H_(2)O,利用回料可以提高混合物料的自由空域、增加了通风生物干化过程中的含氧量从而降低单位水分去除所产生的CO_(2)排放量.未添加回料的实验组TN在生物干化前后未出现明显变化,而回料利用条件下TN由最初的29.4~31.1g/kg WM持续升高至31.6~31.8g/kg WM,这主要是由于干化过程中水分的蒸发和有机物矿化导致的TN的浓缩效应.能量平衡分析结果表明,利用回料可有效降低翻堆和实验过程带来的热量散失,回料:稻草:污泥=1:1:4时水分蒸发所用热量数值最大但占比有所下降,占总消耗热量的78.25%.添加回料可有效提高水分去除以及碳氮保留,同时会增加生物干化后物料的腐熟程度,降低稻草调理剂用量,说明回料利用在食品工业脱水污泥热风系统生物干化中具有优化作用.

不同形态回收碳纤维水泥基材料的力学与导电性能

将碳纤维生命周期内产生的预浸料、织物及复合材料废弃物通过切割与粉碎制备短切回收碳纤维(CRCF)、回收碳纤维球(RCFS)及回收碳纤维粉(RCFP),研究不同形态回收碳纤维对水泥基材料力学与导电性能的影响机理和规律。结果表明,CRCF阻裂作用与RCFP填充孔隙作用使水泥基材料抗压强度和抗折强度显著提升,但RCFS的团聚导致其提升效果不显著。CRCF在水泥基材料内部搭接形成导电通路,电阻率随CRCF掺量的增加而降低,下降幅度超过90%,且渗滤阈值的掺量随CRCF长度的增大而显著降低。RCFS掺入基体后以孤立的球状形态分散在基体中,RCFP表面残留的树脂会阻碍导电通路的形成,这两种形态的回收碳纤维水泥基材料的电阻率降低幅度均小于10.7%。将CRCF水泥基材料中的电阻分为纤维通路电阻、纤维接触电阻和隧道传输电阻,建立了导电模型,模型误差为9.24%~40.1%。

A perspective on sustainable energy materials for lithium batteries

Lithium ion battery has achieved great success in portable electronics and even recently electronic vehicles since its commercialization in 1990s.However,lithium-ion batteries are confronted with several issues in terms of the sustainable development such as the high price of raw materials and electronic products,the emerging safety accidents,etc.The recent progresses are herein emphasized on lithium batteries for energy storage to clearly understand the sustainable energy chemistry and emerging energymaterials.The Perspective presents novel lithium-ion batteries developed with the aims of enhancing the electrochemical performance and sustainability of energy storage systems.First,revolutionary material chemistries,including novel low-cobalt cathode,organic electrode,and aqueous electrolyte,are discussed.Then,the characteristics of safety performance are analyzed and strategies to enhance safety are subsequently evaluated.Battery recycling is considered as the key factor for a sustainable society and related technologies are present as well.Finally,conclusion and outlook are drawn to shed lights on the further development of sustainable lithium-ion batteries.

锂离子电池负极材料的回收与循环利用

随着锂离子电池市场的持续增长,退役锂离子电池量呈指数增加。对废旧负极材料进行回收再利用,能够有效解决废旧锂离子电池造成的环境问题,降低资源消耗成本。综述了近年来废锂离子电池中常用负极材料的回收循环利用研究进展,分析了各种回收技术的特点,总结了锂离子电池负极材料回收再利用的发展方向,并展望了未来锂离子电池负极材料回收再利用技术,以促进电池产业的可持续发展。

GB/T 38471《再生铜原料》新旧标准差异分析

本文结合再生铜行业发展现状,对比了GB/T 38471《再生铜原料》修订前后的差异,研究了标准技术指标变化背后的市场导向及深层原因。修订后的GB/T 38471通过增减技术要求,进一步规范了铜资源的回收利用流程,保障和支撑高品质再生铜原料的进口和规范化回收,对促进资源节约和高效利用起到了积极的作用。

含钌废料回收提纯及循环利用的工艺研究进展

从含钌废料中回收、分离提纯和循环利用钌产品,对于实现贵金属钌的可持续发展、节约资源和资源再生意义非凡。介绍了含钌废料的不同来源,综述了从不同废料开展的回收-分离提纯-制备钌产品的主要工艺方法及其优缺点。固体中钌的回收工艺方法主要有熔融法、氯化法、合金活化法、电解氧化法等;废液中钌的回收工艺方法主要有置换法、沉淀法、电化学法、离子交换法及离子印迹法等;分离提纯工艺方法主要采用酸性氧化蒸馏法和碱性氧化蒸馏法;钌产品的制备工艺方面主要简述了三氯化钌和钌粉的制备工艺和方法。

生活垃圾填埋场开采再利用碳排放模型及其应用

采用碳排放因子法建立了生活垃圾填埋场开采再利用的全生命周期碳排放模型,核算了单位质量填埋垃圾在保持原状、开采-材料再回收和开采-能源回收三种场景的碳排放量,分析了开采再利用场景下碳减排主要驱动因素与碳减排量的影响规律,探究了填埋场开采再利用相对于保持原状的碳减排潜力。结果表明:开采-材料再回收场景的碳排放量少于开采-能源回收场景;开采-材料再回收场景的碳减排量随塑料回收率的提高而增大,开采-能源回收场景的碳减排量随垃圾衍生燃料热处理量的增加而增大;简易填埋场在开采-材料再回收场景的碳减排潜力最大,达-495 kgCO_(2)eq/t。该研究可为我国垃圾填埋场开采再利用的碳减排潜力评估提供一定的参考依据。

舰船柴油主机动力装置的余热循环和利用系统设计

舰船柴油主机动力装置的余热循环和利用对提升舰船能源利用效率以及作战能力都具有重要意义。本文在确定余热循环和利用系统需求的基础上,对舰船柴油主机动力装置的余热循环和利用系统的整体结构进行了设计,系统包括余热回收锅炉系统、动力涡轮系统、有机工质发电系统、汽轮机发电系统、热交换系统以及能量管理系统,最后对柴油主机动力装置的余热循环和利用系统进行了模拟测试。测试结果表明:该系统可以有效利用柴油主机余热,基于ORC循环的系统热回收效率最大可达6.5%,柴油主机余热利用效率最大可达19%。

再生铜和再生黄铜原料的金属回收率研究

金属回收率是评价再生金属资源品质的重要参数。然而再生铜原料及再生黄铜原料的国家标准GB/T 38471—2019和GB/T 38470—2019中并未对金属回收率实验的技术内容作出明确规定,致使各实验室对金属回收率实验的结果不一。通过考察不同种类的再生铜原料及再生黄铜原料的回收率影响因素,重点探索样品成分、检验设备的差异及对应的不同熔炼功率、不同种类除渣剂的影响等因素所导致样品的回收率偏移,并以镀白紫铜为案例使用扫描电子显微镜观察与分析了金属回收率副产物的形貌及组成。结果表明:再生铜原料及再生黄铜原料中的合金成分是影响金属回收率数据的主要因素,再生纯铜原料中铜含量较高且结构简单,因此在实验中干扰因素较少,纯铜回收率比合金、镀金类铜更稳定更高,且波动较少;含低熔点合金元素的铜合金中低熔点金属易发生烧损,金属回收率易偏低、含高熔点合金元素的铜合金由于高熔点合金元素不能完全熔化,金属回收率易偏高;多种除渣剂中,除渣效果较好的有硼酸、生石灰及炼钢用打渣剂火山灰,其中后两者效果表现优良。熔炼所得的粉尘和氧化物结块成分以金属氧化物为主,不宜作为可利用的金属加入到金属回收率的计算。

玻璃纤维增强热固性复合材料的回收利用

玻璃纤维增强热固性聚合物复合材料(GFRP)在各种工业领域中被广泛应用,其优异的力学性能和耐腐蚀性使其成为替代传统材料的理想选择。目前,全球聚合物复合材料年产量超过1600万t,并以约8%的年增长率不断增加。然而,GFRP的废弃物处理一直是一个挑战,因为热固性基体难以降解且复合材料很难进行有效的回收利用。据统计,仅有不到10%的废料得到回收利用,特别是在风电行业,废弃叶片的回收面临巨大挑战。随着风电设备的装机容量不断增加,风电叶片的回收需求迫在眉睫。目前,机械粉碎虽然是主要的回收工艺,但化学回收和热解回收处理后的纤维质量较高而显示出更大的潜在优势。然而,各种工艺的需求尚未得到充分的解释,影响了经济价值及工艺可行性评估。总结了玻璃纤维增强热固性聚合物复合材料的化学回收和热解回收利用方法,并讨论了相关挑战和未来发展趋势,旨在推动GFRP废弃物的有效处理和资源化利用。

锂电回收行业Tulsimer树脂在萃镍余液中的镍回收和净化萃取剂的技术研究

简要介绍了锂电三元材料回收的必要性和主流工艺,结合某电池新材料回收企业在湿法萃取结晶工艺中萃镍余液含萃取剂的问题进行实验和具体分析。处理前,该企业萃镍余液中的镍离子含量为0.285g/l,锂离子含量为2.65g/l,萃取剂含量为134mg/l,采用树脂工艺处理后的含量为镍离子未检出,锂离子2.453g/l,萃取剂含量为0.3mg/l。