RUSAL is completing the development of detailed steady-state mathematical models of technology of its alumina refineries. Models have been developed for refineries with different technologies: Bayer process, parallel Bayer-sintering and sintering method. Each model includes: equipment specifications for production sites, mud disposal, CHPP. The control logic of the model reproduces a refinery control system. A large number of laboratory studies have been performed for development of thermodynamic and kinetic models for digestion processes and impurities equilibrium in liquors. Several types of problems are solved using these models: sensitivity investigations, "What-if" analysis, production optimization, business planning and estimation of capital investments efficiency. RUSAL has organized departments of mathematical modeling at refineries and central development team in its St.-Petersburg office. These specialists monitor technological process, perform routine calculations every day. They prepare solutions for managing of technological process to achieve ultimate efficiency of refinery based on their experience and results of modelling.