Cement Industry

Application of CFD in Cement Industry

 

Cement production involves calcination of raw meal generated by coal or petcoke combustion in Kiln and calciner. In the pyro section, the raw meal converts to clinker. Almost 60% of the calcination of raw meal is completed in calciner and the remaining in long, rotating, horizontal Kiln. The raw meal is preheated in a series of preheated cyclones before calcination. The hot clinker needs to be cooled with the help of air coolers and crushed in crushers to fine particle size. During calcination of raw meal, the heat required for calcination is supplied by combustion of primary fuels like coal, petcoke, tyres or alternative fuels. Thermal NOx is produced due to high temperatures . The side product of calcination is carbon dioxide. It is a highly energy intensive process and produces large quantities of gaseous pollutants like CO2, SO2 and Nitrogen Oxides. Reduction in energy consumption and reducing pollutant formation  is a key challenge for the cement Industry.

 

The main equipments and challenges in a cement Industry are following: 

  • Cyclone: High pressure drop, low collection efficiency, cut size, regular erosion/corrosion;

  • ESP, Bag Filter: Collection  efficiency;

  • Separators: Pressure drop, separation efficiency, PSD not as per design, higher air requirements;

  • Fans: Higher power consumption, fan blade erosion, higher pressure drop;

  • Chimney: Pollutant dispersion, wall erosion, condensation;

  • Calciner: High NOx, lower degree of calcination, higher fuel consumption, incomplete fuel combustion, use of alternate fuels, optimal location of fuel, air, raw material feeding, lower residence time;

  • Kiln: NOx, Hot spots, flame temperature, shape, clinker quality, pressure drop, burner design for alternate fuels, CO reduction;

  • Ducting: Higher pressure drop, air mixing

How can our team contribute using CFD in the Cement Industry?  

 

CFD is very commonly used in the cement Industry to reduce thermal, electrical power consumption and pollutants emissions. As a chemical engineer, having in-depth chemical process knowledge and strong experience of application of CFD and process modeling to improve the performance of cyclone separators, improve combustion, calcination and pollutant reduction in calciners, and Kiln.

To be contributed:

  • Re-design of cyclone to reduce pressure drop and improve collection efficiency;

  • Burner design for the cement Kiln for CO, NOx, SOx reduction using coal, petcoke, alternate fuel;

  • Calciner modeling for identification of optimal location for meal and fuel injection;

  • Re-design of duct layout to reduce pressure drop;

  • Development of a software for automated CFD cyclone design;

  • CFD modeling can help to develop and validate coal combustion models for kiln burner design.

  • Applied the kiln model for reduction of CO in cement Kiln for different units;

  • Development of CFD model for ESP, the flow model and particle collection model under the influence of electric field. CFD modeling can suggest modifications to improve efficiency.

  • Help to develop the process model to improve in the energy efficiency way.