EAGER: A bio-inspired approach for enhancing lifetime of salts during icing and frost formation

EAGER：一种仿生方法，可在结冰和结霜过程中延长盐的使用寿命

• 批准号: 1644815
• 负责人: Sushant Anand
• 金额: $ 10万
• 依托单位: University of Illinois at Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-15 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1644815&HistoricalAwards=false
• 关键词: EAGER; bio; inspired; approach; enhancing

#1644815Anand, SushantInvestigating chemically enhanced salt particles with extended lifetime for ice and frost preventionIce formation on roads can have profound effects, including car accidents, traffic congestion, and billions of dollar losses in economic productivity. To date, the most viable solution worldwide is to use deicing salts on roads that suppress ice formation through freezing point depression. However, their usage also poses significant threats to our environment and economy. Nearly 43% of salt usage related to deicing highways (costing around $2.2 billion) in USA alone. Deicing salts increase the soil salinity near roads causing higher alkanity, increased moisture retention and loss of soil fertility, thus adversely affecting plant growth. The salt can also percolate through soil, ultimately reaching lakes and underground water systems where the increase in salinity can lead to significantly harmful effects on flora, aquatic/amphibious animals and our own drinking water supplies. Furthermore, deicing salts have serious consequences for our infrastructure by promoting corrosion of steel (e.g. in bridges, vehicles) or disintegration of concrete. This study proposes that the lifetime of salt can be increased by enhancing them with special environmentally friendly chemicals that can decrease the dissolution rate of salts while maintaining their deicing functionality. These studies will also lead to development of new understanding of the fundamentals of phase change of water to ice in the presence of a hygroscopic material (such as salt). The work will lead to development of a new class of deicing salts that will have significantly large lifetime compared to conventional salt and will be beneficial for both transportation safety and environmental sustainability.A salt particle can suppress ice formation due to two mechanisms - by depressing the freezing point of water, and by depressing the vapor supersaturation in its vicinity by acting as a "humidity sink". Chemically enhanced salt particles that may maintain their hygroscopic properties but also slow the leeching of salt molecules in the environment during dissolution will be prepared. Experiments will be performed to: (a) to fabricate chemically enhanced salt particles, and investigate scalable techniques for preparing such materials, (b) investigate the deicing delays through use of chemically enhanced salt particles compared to plain salt particles at different thermodynamic conditions (humidity levels, degree of subcooling), (c) investigate the salt leeching rate as a function of chemical properties and thermodynamic conditions. These tasks will be accomplished using combination of thermographic and optical techniques during in-situ observation of ice formation on the chemically enhanced salt particles. In addition to the development of a new type of deicing salt particles with enhanced lifetime, the proposed studies have the potential to shed new light on ice formation in presence of hygroscopic chemicals such as salts.

#1644815 Anand，Sushant研究具有延长寿命的化学增强盐颗粒以防止结冰和霜冻道路上的冰形成可能产生深远的影响，包括车祸，交通拥堵和数十亿美元的经济生产力损失。迄今为止，世界范围内最可行的解决方案是在道路上使用除冰盐，通过降低冰点来抑制结冰。然而，它们的使用也对我们的环境和经济构成重大威胁。仅在美国，近43%的盐用量与除冰高速公路有关（耗资约22亿美元）。除冰盐增加了道路附近的土壤盐分，造成更高的碱性，增加了水分保持和土壤肥力的损失，从而对植物生长产生不利影响。盐还可以渗透土壤，最终到达湖泊和地下水系统，其中盐度的增加可以导致对植物群、水生/两栖动物和我们自己的饮用水供应的显著有害影响。此外，除冰盐通过促进钢铁（例如桥梁、车辆）的腐蚀或混凝土的分解对我们的基础设施产生严重后果。这项研究提出，可以通过使用特殊的环境友好化学品来提高盐的寿命，这些化学品可以降低盐的溶解速率，同时保持其除冰功能。这些研究还将导致对在吸湿材料（例如作为盐）存在下水到冰的相变的基本原理的新理解的发展。这项工作将导致一类新的除冰盐的开发，与传统的盐相比，它将具有显着更长的寿命，并将有利于运输安全和环境可持续性。由于两种机制，盐颗粒可以抑制冰的形成-通过降低水的凝固点，并通过降低其附近的蒸汽过饱和作为“湿度汇”。将制备化学增强的盐颗粒，其可以保持其吸湿性，但也可以在溶解期间减缓环境中盐分子的浸出。将进行实验以：（a）制造化学增强盐颗粒，并研究用于制备此类材料的可扩展技术，（B）研究在不同热力学条件（湿度水平、过冷度）下通过使用化学增强盐颗粒与普通盐颗粒相比的除冰延迟，（c）研究作为化学性质和热力学条件的函数的盐浸出速率。这些任务将在现场观察化学增强盐颗粒上的冰形成过程中使用热成像和光学技术相结合来完成。除了开发一种寿命更长的新型除冰盐颗粒外，拟议的研究有可能揭示在盐等吸湿化学品存在下冰的形成。