Sewage sludge is the mud-like material that remains after treatment of the wastes that flow into local sewage treatment plants. Sewage treatment plants inevitably receive industrial and household toxic wastes. The US Environmental Protection Agency said this about sewage sludge: “Typically, these constituents may include volatiles, organic solids, nutrients, disease-causing pathogenic organisms (bacteria, viruses, etc.), heavy metals and inorganic ions, and toxic organic chemicals from industrial wastes, household chemicals and pesticides.”

Because of the environmental concerns, many jurisdictions are limiting or banning the use of sewage sludge on agricultural land. Landfilling or incineration is the most common practical disposal methods for sewage sludge.

The ROC processes untreated sewage sludge, without odour, pollution, while generating thermal and electrical energy. This makes the solution ideal for water treatment works and industrial manufacturers with sewage waste output as well as providing a self-sustaining energy source.