Modeling and simulation of cement clinkering process with compact internal burning of carbon

This article describes a mathematical model of the thermodynamic process for Cement Clinkering Process with Compact Internal Burning of Carbon. Using simplifying assumptions, results of calculations are presented based on relevant computerized numerical simulation for a set of typical process parameters obtained from the existing cement shaft kiln operation and the electrical furnace test on the mechanical and chemical performance of the compact coal containing cement raw meal pellets. It is revealed that, the carbon internal burning mode, combining fuel combustion and gas solid heat transfer together as well as preheating, calcining, clinkering and cooling of the raw pellets together, is the origin of the process superiority in respect of equipment simplicity, process enhancement, high energy efficiency and low pollution. Important process details are determined, e.g. the features and lengths of the process zones, the material residence time and the burning mode of carbon in each zone, the clinkering reaction course and the maximum burning temperature. It is concluded that numerical simulations could be useful tool for understanding the new process ideas, as well as conducting the technical development and optimizing the process design.