Researchers convert water to ethanol

By: Kimberly Cox

Posted: 10/30/07

Kevin Stevens with the environmental sciences department will help process the wastewater of Denton's ethanol plant, when it comes online in May.
However, his research starts much earlier. Stevens said as soon as TetraPoint Fuels, a company out of Flower Mound, has samples of the wastewater the plant will produce, he and other faculty members will work to create a marsh environment to process the wastewater.
"We're going to be looking at different ways to process it," Stevens said. "We do have some ideas of vegetation."
The plant will produce ethanol, yeast and wastewater. Tim Geiger, president of TetraPoint Fuels, said the plant will process liquid waste products from the beverage industry. In other words, it processes bottles of coke, sports drinks and other beverages.
"Instead of dumping it down a drain or a landfill, we will collect the waste and turn it into ethanol," Geiger said.
The process begins by fermenting the liquids into a "nasty-tasting beer." The taste doesn't matter, Geiger said, just the highest level of alcohol. The water and the yeast are separated from the alcohol. The company will sell the yeast for fertilizers and the wastewater is where Stevens comes in.
When considering places to build their plant, Geiger said they chose Denton not only because it was business friendly, but it also has two universities.
The biological sciences department has a 400-acre aquatic sciences lab. Stevens said the company plans on having a prototype of the plant running in a couple of weeks. The company will then give the department samples of the kind of wastewater the plant will produce, he said.
"First we have to find out what grows in the water," he said. It will take a while, he said. "We're dealing with biological systems, and they don't always do what you want them to."
Stevens will look at types of lilies, floating plants and other aquatic plants that will use the water to produce pure, balanced water, he said.
"We're trying to pick two, three, four species from each of those types," he said.
It will take a while to get things right, he said, but once they get the samples, they can work in the Environmental Sciences Building. From there, they will move the process to the aquatic lab located west of Denton, where they have several small containers for study and several larger ponds to expand study.
Stevens said part of the research will find possible crops to grow in the wastewater. These crops could be cash crops, he said, for agricultural purposes, or even possibly to produce biodiesel or more ethanol.
"There are a number of potential crops we could use for biodiesel or harvest for ethanol, if they have enough sugar content," he said. "A number of crops have an oil content that could be utilized for biodiesel which may be compatible with a wetland setting."
Geiger said he hopes the plant, once fully operational, will produce four to five gallons of ethanol per year. Chris Bell, vice-president of TetraPoint, said the plant will be almost entirely eco-friendly. All the containers that go into the plant will be recycled as well. Bell said the only problem might be if the liquid waste comes in milk or juice cartons, which are difficult to recycle because they are lined with plastic to prevent leakage. The plant even saves on carbon emissions, he said.
"One gallon of ethanol saves 7.5 pounds of carbon dioxide from going into the atmosphere, and saves .66 gallons of gas," Bell said.