Treatment of Wastewater Containing Runway De-Icing Agents in Biofilters as a Part of Airport Environment Management System

Abstract

Large volumes of pavement de-icing and anti-icing fluids, collectively termed de-icing agents, are used at airports to facilitate wintertime safe air travel. After use, most of the them get typically mixed with storm water runoff and may enter soil and waters near the airports. Wastewater resulting from airports’ winter operations is contaminated mainly with nitrogen and carbon compounds. Previous research results have shown that the use of biofilters filled with lightweight aggregates prepared from fly ash from sewage sludge thermal treatment (FASST LWA) could be an effective method for removing nitrogen and organic compounds at low temperatures, i.e., 0–8 °C. For this to be possible, it is necessary to maintain a proper ratio between the amounts of carbon and nitrogen in the treated wastewater, through the simultaneous application of de-icing agents containing urea and carbon compounds. Biofilter technology is part of the concept of sustainable development. Their filling is made of waste materials and one of the pollutants (organic compounds) present in the wastewater is used to remove other pollutants (nitrogen compounds). In this study, technological systems for the treatment of wastewater containing airport runway de-icing agents with biofilters were proposed, which allow for the treated wastewater to be discharged into natural waters, soil, and sewerage network.

Airport Runoff Management: Engineering Solutions

“…As a result of analysis of international and national experience (Baxter et al, 2019, Majd, 2014, Rodziewicz et al, 2020, Xie et al, 2016 it is advisable to adopt the developed system of treatment facilities by the scheme -accumulation of surface runoff with pre-treatment and filtration.…”

“…Operation details of water treatment equipment are presented using the removal of the most hazardous and difficult to remove specific pollutants of airport surface runoff -ethylene glycol, urea, potassium formate, and sodium (Baxter et al, 2019, Rodziewicz et al, 2020.…”

“…Due to the lack of up-to-date data of surface runoff analyses before the developed treatment facilities of the studied airport, the pollution parameters were taken according to the standards (Rainwater drainage systems. Building design standards, 2012) and data of the peer airports (Majd, 2014, Rodziewicz et al, 2020, and parameters of the treated runoff -according to the manufacturer (Xie et al, 2016) (Table 6, Figure 5). The wastes of surface runoff treatment from the territory of the investigated airport are sludge of dewatering units, with humidity of 80%, and oil products (oil sludge), the parameters of formation of which are defined as follows.…”

The Kinetics of Pollutant Removal through Biofiltration from Stormwater Containing Airport De-Icing Agents

“…It is characterized by a large specific surface, resistance to physicochemical factors, low heat conductivity, good phosphorus-sorption properties, and facilitates the deammonification process. These attributes provide good conditions for biofilm growth even at low temperatures [5,6].…”

“…The previous authors' research has shown that biofilters LECA filling could be an effective method for removing nitrogen and organic compounds from wastewater containing airfield deicing fluids. The nitrogen compounds were removed as a result of the simultaneous process of nitrification and denitrification, where the organic compounds present in the treated wastewater served as a carbon source [5,14]. To that end, the present paper provides the findings of a study aimed to determine the transformation kinetics of pollutants generated from airport maintenance, providing a means to estimate the retention time for de-icing wastewater in filters located near airports or in individual, local systems for removing such pollutants.…”