Treatment and reuse of spent pot lining, an industrial application in a cement kiln

The treatment of Spent Pot Lining (SPL) has been occasion of numerous studies in the world. Several processes have reached the commercial stage in USA, Australia and Europe. Most of these processes generate waste that needs to be disposed of. An other approach is to make total use of the SPL constituents, with no waste disposal and with no air emission. Among several processes allowing reuse of SPL, one is highlighted here : the addition of second cut (refractory) SPL to quarry materials in the raw feed of a Cement Kiln. Under close supervision of the French Environment Protection Authority, ALUMINIUM PECHINEY has developed a partnership with CIMENTS D'ORIGNY including an R&D programme to demonstrate the capability of a Cement Kiln to accept SPL as a raw material despite the presence of sodium and fluoride. Since 1997, SPL are now recycled industrially in a Cement Plant in northern France.