FROM THE 'LOW CAUSTIC LEACHING AND LIMING' PROCESS DEVELOPMENT TO THErnJONQUIÈRE SPENT POTLINING TREATMENT PILOT PLANT START-UP, 5 YEARS OF PROCESSrnUP-SCALING, ENGINEERING AND COMMISSIONING

摘要

The LCL&L process is a hydrometallurgical route developed byrnresearchers of Rio Tinto Alcan (RTA) to treat, bothrnenvironmentally and economically, spent potlining (SPL)rngenerated by aluminium cells. Considering local characteristics,rnincluding the low capacity of cement producers to recycle SPL,rnthere is a high SPL inventory that has accumulated over the lastrn25 years. LCL&L was selected as the preferred solution for therntreatment of RTA’s SPL in Quebec, and as a sustainable solutionrnfor other Quebec aluminium producers. This paper describesrnLCL&L process characteristics, including valorization alternativesrnfor the by-products and special chemical analysis methodsrndeveloped for process control. Some technological challengesrnfaced and managed during scale-up from laboratory and mini-pilotrnprocess development, design and construction of the industrialrnscale pilot plant will be discussed. Finally, preparations for thernplant commissioning, start-up in April 2008 as well as some earlyrnoperational highlights will be discussed.