Published on March 17th, 2013 | by Tina Casey3
NYC Sewage Gets A First-of-Its Kind Green Makeover
Glycerol is better known as a common ingredient in pharmaceuticals, foods, soaps and perfumes, but lately it’s been wandering off into strange new territory, popping up here and there as a green chemistry alternative to petrochemicals. In the latest development, glycerol (aka glycerin or glycerine) has been successfully deployed as the main ingredient in an innovative new nitrogen removal system at a New York City wastewater treatment plant. It’s the first such facility of its kind in the U.S…and did we mention that this is great news for the biofuel industry, too?
Green Chemistry Goes To Work On Wastewater
New York’s new glycerol facility is located at its 26th Ward Wastewater Treatment Plant in Queens. It is helping to improve the municipal wastewater treatment process by removing excess nitrogen from effluent before it is released into surrounding waterways (too much nitrogen = dead fish and other problems).
During the second phase of the standard treatment process, air is pumped into tanks, where ammonia in the partly treated wastewater breaks down into nitrates and nitrites. The new facility adds glycerol as a source of carbon to separate out the nitrogen.
The facility has been in operation for a little over a year and it already helped to reduce nitrogen discharges from 5,800 pounds per day as of December 2011 to 1,900 pounds per day as of March 2013. As recently as 2010 the treatment plant was discharging 11,000 pounds per day, so that’s a huge improvement.
The green chemistry kicks in here because glycerol replaces methanol as a carbon-rich nitrogen remover. Methanol is a highly flammable liquid once made through a distillation of wood (it’s still sometimes called wood alcohol), but today’s conventional methanol is made from natural gas and other fossil sources.
The new facility, which is apparently the first of its kind in the U.S. to use glycerol for nitrogen removal, was recently named National Recognition Award Winner for 2013 by the American Council of Engineering Companies, and New York plans to implement the same system at its other wastewater treatment plants
Solving Biofuel’s Glycerol Problem
New York’s new nitrogen removal facility uses glycerol that is produced as a byproduct of biofuel production, and that’s a major sustainability twofer because it will help the biofuel industry solve a major waste disposal headache.
Though pure glycerol is a high-value product, crude glycerol is another thing. The biofuel industry produces massive amounts of crude glycerol, and in order to sustain itself financially as well as environmentally it needs to find new markets for crude glycerol.
Some of the other crude glycerol developments we’ve been following are its use in microalgae farming, cattle feed, “green” antifreeze, sustainable hydrogen gas production and sustainable methanol production.
On the more exotic end of the scale, a team of researchers based at the U.S. EPA’s National Risk Management Laboratory has just published a paper showing that glycerol can be used to fabricate nanoscale structures of gold, platinum and palladium, making it a potential substitute for toxic substances used in conventional nanomaterials synthesis.
Since the U.S. Navy is all over biofuel, it should also be no surprise that the Navy has some interest in supporting the development of sustainable uses for crude glycerol. Keep your eye on the new integrated biorefinery system under construction by a company called Biodico at Naval Base Ventura County in California. Part of the system involves recycling glycerol back into biorefinery operations in order to speed up processing, as well as recovering other high value products.