Common Algae for Biofuel Butanol Production
There have been various methods tried for reducing fossil fuel dependency and containing carbon footprints for a healthier and more eco-friendly future. Corn-produced ethanol has been used for mixing with gasoline but there have been side effects like corrosion from ethanol. Also huge tracts of precious farmlands need to be diverted for corn production. But now new research has thrown up results that show common algae can be used for biofuel production.
There has been research going on in University of Arkansas by a group of chemical engineers and research students of Honours College led by Asst. Professor & Project Leader, Jamie Hestekin. The focus is on converting the common algae into renewable fuel which can be used in automobiles with combustible type engines. The research is done on algae which survive on nitrogen, phosphorous, sunlight and carbon dioxide; and from which, organic acids and subsequently biofuel is produced.
Growing algae on ‘raceways’
Long trench-like troughs – about two-foot wide and variable lengths are used for cultivating the algae. On a base of screens or carpet – actually any base works – they let normal river water to run in the troughs. The nitrogen and phosphorous in the water helps a lush growth of algae in sunlight which further receives carbon dioxide delivered in high doses via hollow long fibers. The algae can be harvested every 5-8 days and they keep growing afresh after harvest.
Butanol production made easy
Scraping the algae, drying it, carbohydrates are extracted which are converted to natural sugars. Then via fermentation process, sugars are converted into butyric, lactic and acetic acids. Again butyric acid is converted by fermentation into butanol. This process was made speedier by a special technique called electrodeionization – a process developed by a team member. This makes the entire fuel conversion process faster and less costly.
Utilizing existent ‘dead-zone’ cleaning
Water authorities in municipalities and state departments have been trying to clean up what is commonly called as ‘dead zones’ – water laden with overload of nitrogen and phosphorous which kill the aquatic flora and fauna, and fish etc. They purify and oxygenate the existent water-ways by removing the excess fertilizer run-off nitrogen and phosphorus. And common algae cultivation can be done side by side with the above cleaning process as is done in Rockaway Wastewater Treatment Plant in Queens where the research team and New York City Department of Environmental Protection are working in tandem.
Advantages of the new process
The new conversion process is less expensive and definitely more efficient. Apart from the fact that butanol is far superior to ethanol in efficiency, this process helps the water become less polluted and healthier. The algae use the extra nitrogen and phosphorous in the existent water and make it safer for marine flora and fauna. As Hestekin puts it succinctly, “the coolest thing about this process is that we’re actually making rivers and lakes healthier by growing and harvesting the raw material.”