Department of Civil Engineering, Kansas State University, Manhattan, KS, 66506, USA.
J Environ Manage. 2021 Sep 1;293:112888. doi: 10.1016/j.jenvman.2021.112888. Epub 2021 May 28.
Water softening residuals disposal is a worldwide issue due to the lack of effective reuse alternatives. The current principal disposal methods of landfilling and land application are quite costly due to the dewatering and transportation costs involved, and these operations can also cause potential environmental harm from leaching of the additives used in the treatment process. This research is aimed at the use of water softening residuals in the production of biodegradable road deicers that would be beneficial in replacing the highly corrosive and environmentally harmful chloride salts that are currently used for road deicing. Experimental data developed show that calcium magnesium acetate (CMA) and calcium magnesium propionate (CMP) deicers produced using water plant sludges are effective in deicing applications. A mathematical model is developed for predicting freezing point depression of CMA and CMP deicers as a function of molal concentration. The model predictions are found to match well with the experimental data, providing confidence in the use of this model for the effective design water softening sludge based deicers. The information developed herein provides options for the sustainable management of softening residuals and the concommitant mitigation of environmental harm associated with road deicing operations.
由于缺乏有效的再利用替代方案，水软化残渣的处理是一个全球性的问题。目前，填埋和土地应用是主要的处理方法，但由于涉及到脱水和运输成本，这些方法相当昂贵，而且这些操作还可能导致处理过程中使用的添加剂浸出带来潜在的环境危害。本研究旨在利用水软化残渣生产可生物降解的道路融雪剂，以替代目前用于道路除冰的腐蚀性和对环境有害的氯化盐，这将是有益的。开发的实验数据表明，使用水厂污泥生产的钙镁乙酸盐（CMA）和钙镁丙酸盐（CMP）融雪剂在除冰应用中是有效的。开发了一个预测 CMA 和 CMP 融雪剂冰点降低的数学模型，作为摩尔浓度的函数。模型预测与实验数据吻合良好，为使用该模型进行有效的基于水软化污泥的融雪剂设计提供了信心。本文提供的信息为软化残渣的可持续管理提供了选择，并减轻了与道路除冰作业相关的环境危害。
