Fluidized Bed Advanced Cement Kiln System

 
 

While the rotary klins remains as by far the dominating technology, since the late 1990's a Japanese firm has been developing a completely new kiln type based on fluidized bed technology (FBT).  In this technology, clinker is produced in a fluidized bed system, under addition of grinded coal, and raw material injection. The raw material is granulated in the kiln system to a specific size. Subsequently the clinker is cooled in two steps (fluidized bed quenching and a packed bed cooler). The result is a finely granulated clinker.

The technology offers the following advantages: 

  • The emission of CO2 can be decreased due to reduction of fuel consumption;

  • Due to improvement of the burning and heat transfer characteristics, it is able to use low grade coal such as low volatile coal and low calorific coal.

  • The heat recovery efficiency of the system can be improved by 20 % as compared with the conventional cooler due to increase of waste heat recovery.

  • Both of construction and maintenance costs can be decreased because there are no movable apparatuses.

  • The system is able to control temperature more tightly and keep a longer reaction time, and it enables the quality improvement and the production of special cement with higher grade.

  • The emission of thermal NOx emission can be greatly decreased because combustion takes place in the fluidized bed without generating flame.

It should be stressed that this technology is not yet available in wide scale for the cement industry and probably it will hardly be possible to scale it up to a 5,000 or 6,000 tpd clinker capacity (the demonstration projects in Japan are 200 and 1000 tpd respectively).

 
Development Status Products
Demonstration
clinker

Fluidized Bed Advanced Cement Kiln SystemCosts & Benefits

Parent Process: Clinker Making
Energy Savings Potential

Thermal energy use can be decreased by around 0.4 GJ/t-clinker (NEDO, 2006), while the electricity consumption increases by around 9 kWh/t-clinker (ECRA, 2009)

20% more heat can be recovered in the cooling system, as compared to conventional methods (APP, 2009)

CO2 Emission Reduction Potential

CO2 reductions in the range of 10% can be realized (NEDO, 2006). 

Costs

Fluidized Bed Advanced Cement Kiln SystemSchematic

Fluidized Bed Advanced Cement Kiln System Publications

Development of State of the Art Techniques in Cement Manufacturing: Trying to Look Ahead

The report represents the independent research efforts of the European Cement Research Academy (ECRA) to identify, describe and evaluate technologies which may contribute to increase energy efficiency and to reduce greenhouse gas emissions from global cement production today as well as in the medium and long-term future. 

Page Number: 

52-53

Energy Efficiency and Resource Saving Technologies in Cement Industry

 

This Cement technologies booklet was compiled by the APP Cement Task Force (CTF) through one of its activities to help its member countries share information on all available energy efficient technologies generally used in the world’s cement industry. The document offers a comprehensive compilation of commercially-available energy efficient technologies used in the cement industry.

Page Number: 

77

Page Number: 

53-54