Waste to Energy

[clarencebunsen]

Can New Waste Treatment Make Energy and Profits from Sewage Plants?

Most Americans flush the toilet without thinking twice about where the contents end up, but a handful of companies are paying close attention to what goes down the drain. They argue it should be seen as a resource rather than waste.

Dealing with human waste is a tricky business. The wet material typically has to be treated at a sewage plant, dried and turned into a biosolid, then either hauled away to a landfill or turned into mulch and reused as fertilizer.

According to the U.S. Geological Survey, wastewater treatment plants generate about 7 million dry tons of biosolids per year. The conventional methods of dealing with this waste are expensive and energy-intensive. Landfills are also filling up, and sludge that's turned into fertilizer may still contain chemicals that are potentially harmful to humans and the environment.

Now, some companies are saying this method of dealing with waste is just plain wasteful.

www.scientificamerican.com/article.cfm?id=can-new-waste-treatment-make-energy-profits-sewage-plants