Mitigation of propylene glycol emissions to groundwater and soil
Research output: Other conference contribution › Paper, poster or abstract › Scientific
|Publication status||Published - 5 Sep 2016|
|Event||Nordrocs 2016, 6th Joint Nordic Meeting on Remediation of Contaminated Sites - Aalto-University, Espoo, Finland|
Duration: 5 Sep 2016 → 8 Sep 2016
|Conference||Nordrocs 2016, 6th Joint Nordic Meeting on Remediation of Contaminated Sites|
|Abbreviated title||Nordrocs 2016|
|Period||5/09/16 → 8/09/16|
Propylene glycol based deicing agents are used at airports to remove ice and prevent ice accumulation into airplanes. Propylene glycol is readily biodegradable both aerobically and anaerobically but it has been noticed to migrate into groundwater (Greco et al., 2012). Currently propylene glycol emissions are collected and treated at municipal treatment plants. More information is needed about mitigation measures to prevent propylene glycol emissions into ground water and soil.
The objective of current study was to study whether low cost materials can improve propylene glycol degradation in soil and decrease its migration into groundwater and soil at low temperatures. The low cost materials were chosen based on literature survey and small scale laboratory experiments as well as technical parameters and current use at Finnish airport structures. Experiments were carried out in two pilot-scale temperature controlled lysimeters (height 3 m, radius 50 cm) operated at -5 to 20 ̊C, i.e. simulating winter, spring and summer conditions to compare control lysimeter and amended lysimeter. Deicing agent was mixed with flake ice in order to simulate snow and added on top of the soil and/or amendments. The purpose was to find out whether addition of peat and blast furnace sand can mitigate propylene glycol emissions.
Lysimeter leachate formation and migration of propylene glycol into lysimeter leachate were minimal when the soil was frozen. Biodegradation of propylene glycol was detected as formation of its degradation products in both lysimeters after the soil temperature had increased above 0 ⁰C. However, comparison of results from control lysimeter and lysimeter amended with peat and blast furnace sand revealed that the amendments did not improve biodegradation of propylene glycol nor decrease its migration into lysimeter leachate.