Wastewater Sludge Becomes Biodegradable Plastic in New Process From Micromidas
Wastewater sludge is a big disposal problem, since up to 40% of a wastewater treatment facility's operating budget is devoted to handling wastewater sludge
Bio-refinery company Micromidas saw that wastewater sludge was a big problem for wastewater treatment facilities everywhere. Wastewater treatment facilities generate a lot of sludge that is expensive to handle for disposal. Up to 40 percent of a wastewater treatment facility's operating budget is devoted to handling the noisome stuff. But now bio-refinery firm Micromidas has a good idea what to do with the sludge. They propose to turn it into biodegradable plastic.
(See this cnet article for more information on bioplastic technology.)
The Sacramento, California firm has now done tests of a shipping container-sized bio-refinery that converts carbon-rich wastewater sludge to polyhydroxyalkanoates (PHA) plastic. The process involves using microbes that feed on and digest the nutrients in wastewater sludge, and then later harvesting the microbes to make plastic.
(See these articles for other news updates about bioplastic technology: Bioplastic from algae coming soon , Bioplastics almost ready for mass market , Dying to throw all your plastic in compost? Biodegradable plastic is on its way)
Different microbes in varying quantities are used depending on the microbial nutrient composition of the sludge. Chemical engineers at Micromidas use Autodesk’s Algor simulation software to run virtual experiments to determine which mix of microbes and processes work best.
Micromidas does not yet know what the price tag will be on their wastewater bio-refinery product compared to established methods of making PHA with sugars such as glucose or fructose. Hopefully, the cost will be reasonable enough to encourage wastewater sludge recycling at wastewater treatment facilities nation-wide.