June 30, 2009

Water treatment plant mud is ‘green’ fuel

Spanish scientists say mud from waste water treatment plants can be an alternative fuel, enabling cement factories to reduce their carbon dioxide emissions.

Researchers from Virgili University said the use of such mud can also help factories comply with the Kyoto Protocol, as well as posing no risk to human health and being profitable.

The environmental impact assessment analyzed the environmental and human health impacts of using solid waste from large city water treatment plants as an alternative fuel.

As this mud is already waste, burning it does not enter into the atmospheric CO2 emissions assigned to each country under the Kyoto Protocol, said Jose Luis Domingo, lead author of the study and director of the university's Toxicology and Environmental Health Laboratory.

That would enable plants producing cement, one of the most contaminating industries in terms of CO2, as well as emissions of dioxins, furans and heavy metals, to consume energy in a more environmentally-friendly way, Domingo said. Up to 20 percent of the fossil fuel energy used at a Catalan cement plant studied by the scientists has been replaced by waste water treatment plant mud.

The study appears in the journal Environmental Science and Pollution Research.