Numerical Simulation Of NSP Cement Firing System

Entering the 21st century, a new era for the economic development has a new requirement, not only requires production efficiency, and low carbonation. As is known to all, cement production is high pollution and the high-energy operation, and many experts are trying to develop a plan,which can let the production as energy conservation, greening. Along with the computer technology, combined with the high-speed development of fluid mechanics, numerical analysis, and other disciplines, computational fluid dynamics is emerged, and is widely used in cement industry in recent years, providing a theoretical support for the design and optimization of production.At present, the NSP cement is developing rapidly, to cater to a low carbon economy, all traditional long kiln production mode should be eliminated, NSP cement has already become the mainstream. The predecomposition firing system including suspension preheater, decomposition furnace and rotary kiln, the internal flow field is very complex. Grasping the internal flow field in law will provide a reference for the design and production. In this case doing experiments is unrealistic, and introducing computational fluid dynamics make it reality. Computational fluid dynamics (CFD) is under control in flow equation of the numerical simulation of the flow. The numerical simulation can get the complex flow field each position of distribution, and the basic physical changes.In short, it is an experiment on the computer.Aiming at the predecomposition firing system three main parts of the flow field characteristics, adapting different solution model, simulate the internal hot state flow field of cyclone preheater, decomposition furnace and rotary kiln, analyzes its internal flow pattern. To numerical calculate cyclone preheater, the UDF and the multiphase flow model is taken,and consider the category of dust affect. The obtained results compared with design data, and category five and six do contrast analysis, provides the reference for the series design;In numerical calculation of rotary kiln, the rotary kiln is designed as a long kiln body with burner。No considering material decomposition, numerical calculation its internal heat flow field, obtain the reasonable flow field distribution and calculate the exit NOx cargoes of nitrogen oxides;In the calculation of internal flow field of decomposing furnace, consider the meal calcining by transmission model, do numerical simulation of components,and calculate decomposing efficiency, get each field quantity internal distribution field, considering the pulverized coal and natural gas for fuel, and finally get mass concentration of nitrogen oxides, and compared with actual situation, and puts forward some solutions to reduce nitrogen oxides, provide theoretical support for designing of decomposing furnace.