01552139

Component

Agro-based products and complex chlorides/minerals (CCM) based products are increasingly employed in snow and ice control operations, either used alone or more commonly as additives for chloride-based products. Recent studies have shown that agro-based or CCM based products have the potential to improve the overall deicing and/or anti-icing performance and reduce the corrosion and environmental impacts. However, the effectiveness of such products has been limited to qualitative field observations and their specific role in snow and ice control is poorly understood. This work consists of a systematic laboratory investigation, with a focus on the thermal properties, ice melting behavior, and corrosivity of four agro-based deicers and two CCM based deicers. First, CCM based deicers do not exhibit significantly better ability to lower the freezing point of water when compared with sodium chloride (NaCl), but they feature slightly better ice melting capacity at 15° F than NaCl. Second, agro-based additives seem to significantly lowered the freezing point of 23 wt.% NaCl brine but do not significantly improve the ice melting capacity at 15° F or 25° F, implying their role as 'cryoprotectants’. Third, CCM and agro-based deicers do not exhibit significantly lower characteristic temperature than reagent-grade NaCl. A very strong positive linear relationship exists between the eutectic temperature (Te) and the characteristic temperature (Tc) of the tested liquids, indirectly confirming the validity of using differential scanning calorimetry (DSC) thermograms to assess liquid deicers. The gravimetric method reveals that CCM based deicers exhibit slightly lower corrosivity to carbon steel than NaCl and agro-based additives exhibit significant benefits in reducing the corrosivity of 23 wt.% NaCl brine. The electrochemical method reveals that while the beet-based additives do not significantly alter the corrosion potential of carbon steel, the other type of additives moved the corrosion potential to a much more positive level, implying anodic type inhibitor at work.

This paper was sponsored by TRB committee AHD65 Winter Maintenance.

01550057

15-5815

English

21p

2015

Transportation Research Board 94th Annual Meeting

Digital/other

Figures; Photos; References; Tables

Carbon steel; Chlorides; Corrosion; Deicing chemicals; Freezing point; Laboratory tests; Snow and ice control; Thermal properties; Waste products (Materials)

Highways; Maintenance and Preservation; I62: Winter Maintenance

Transportation Research Board Annual Meeting 2015 Paper #15-5815

PRP, TRIS, TRB, ATRI

Dec 30 2014 1:57PM