A large international airport maintained
a large storm water collection system designed to
capture the de-icing fluid during the winter. A
large majority of the deicing fluid is captured
and recycled. The excess fluid that runs off the
plane during take off is collected in the storm
water collection system for subsequent treatment
at the WWTP. Unfortunately the large rains filled
up the storm water collection system faster than
the wastewater plant can take the water. The problem
came to a head when the "dike sprung a leak."
The hole was plugged but the water remained too
high. The MDEQ verified that there is no remaining
glycol in the water and therefore if the dissolved
oxygen can be maintained above 5 ppm, the airport
can discharge it.
DynamOx was used to supplement the DO as the
discharge passes. The airport staff measured the
downstream dissolved oxygen as they slowly increased
the pond discharge rate to in excess of 20 MDG.
The airport staff included a safety factor, while
independent downstream dissolved oxygen reading
exceed 5 ppm even though the nearby influent drain
has a DO below 1 ppm.
Anyone that has worked around deicing liquids knows the pungent "onion like" odor that is associated with degrading glycol. As these deicing fluids degrade, other offending odors are generated (notable hydrogen sulfide).
Without discussing the "maximizing the yield of free energy" it suffices to say that odors, such as hydrogen sulfide, methane, and ammonia are formed. The addition of large amounts of oxygen can rapidly shift the ORP (oxygen reduction potential) and change the form of the sulfur, nitrogen, and other elements resulting in the elimination of the odors. The process of increasing the ORP to eliminate odors has been well known for years but typical aeration equipment used bubbles to introduce the oxygen. The aeration process encourages the odor to "off-gas" and increases the H2S concentrations in the air. DynamOx does NOT strip the odors.
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