Plasma Arc Gasification for Solid Waste Disposal: Update on St. Lucie County, Florida Project

Plasma arc gasification is an emerging technology for generation of renewable energy and other by-products from a variety of waste. This bold technology is under development in a number of locations around the world, although it is too early to fully know if the technology is technically feasible and economically viable on a truly heterogeneous municipal waste stream like that found in the U.S. Plasma arc technology in the United States in other applications dates back approximately 40 years when it was utilized by NASA to test heat shield materials for spacecraft. In 1989, plasma arc technology was used in an iron melting furnace in Defiance, Ohio (USA). Plasma arc gasification has been used in municipal solid waste destruction since 1999 in Japan for destruction of solid waste and automobile shredder residue. Plasma arc gasification heats waste materials to temperatures in excess of 10,000 degrees Fahrenheit (°F) to break the molecular bonds and gasify the materials. This liberates the energy potential of the waste materials and melts the residue to an inert, glass-like slag, which may be used as an aggregate in construction and manufacturing operations. If this market can be developed, it will significantly reduce the need for landfill disposal in the future. St. Lucie County, Florida (USA), is in the process of negotiating with a developer for the construction of a plasma arc gasification facility that will process 1,000 tons per day of municipal solid waste. The facility may be the first large scale solid waste plasma arc processing facility in the United States. Camp Dresser & McKee is assisting St. Lucie County to negotiate the agreements for this project. The project is expected to be privately financed, so the County will not be putting any money at risk. In this paper, we will describe the plasma arc technology, present its historical applications, and discuss the St. Lucie project from initial conception to its current status.