Ventless grate coolers-now practical?

The development of a ventless grate cooler system for cement clinker began in the early 1970s with the goal of eliminating process dust emissions from the cooler and improving recuperation efficiency. To date, there are, worldwide, only a few ventless cooler systems in operation. This paper outlines the application background of these systems and the technological changes made for their adaptation. The principle systems: conventional grate coolers, recuperator grate coolers with duotherm systems and recuperators with g-Coolers are illustrated by flow charts, and the cooling systems that can be designed for ventless operation, grate coolers with duotherm systems and g-Coolers, are compared. Operating results of these systems are discussed including system designs and operational parameters which allow the ventless cooler to operate satisfactorily during upset and unstable kiln conditions. The system comparison includes investment costs, power consumption, temperature during kiln upset conditions and process control philosophy