Minimization of Life Cycle Environmental Impact and Cost in the Operation of Steam and Power Plants

MARTINEZ P. E.; ELICECHE A. M.

Pucón, Chile

Conferencia; III INternational conference of life cycle analysis; 2009

United Nations Life Cycle Initiative

The selection of the operating conditions of the steam and power generation sector of an ethylene plant is carried out minimizing the environmental life cycle impact and operating cost solving a Mixed Integer Nonlinear Programming problem. The battery limits of the utility plant are extended to include the main environmental impacts corresponding to the electricity imported generated by nuclear, hydroelectric and thermoelectric plants. The life cycle environmental impacts due to natural gas feedstock are also considered. When the environmental life cycle impact and operating cost are minimized the optimal solutions are similar. Significant reductions in life cycle environmental impact and cost are achieved, selecting the operating conditions such as temperature and pressure of high, medium and low pressure steam headers. The operating conditions include discrete decision for the selection of alternative drivers, between electrical motors and steam turbines, and equipment that are on or off, which are represented using binary variables in the mixed integer nonlinear programming problem.