High-Efficiency Separators/Classifiers for Finish Grinding

In high-efficiency classifiers, the material is more cleanly separated, thus reducing over-grinding. High efficiency classifiers or separators have had the greatest impact on improved product quality and reducing electricity consumption. Grinding capacity can increase by up to 25%. 

Indian flag Capacity inreases in the range of 10% to 15% are reported from India. 

Chinese flagAs of 2009, high efficiency separators/classifiers had a penetration rate of around 35%. This figure is expected to rise to 75% by 2015, potentially saving 1.6 million tce of energy annually (NDRC, 2009. p.46).

Development Status Products
Commercial
Cement

High-Efficiency Separators/Classifiers for Finish GrindingCosts & Benefits

Parent Process: Finish Grinding
Energy Savings Potential

Electricity savings between 0 to 7 kWh/t cement are reported dependent on the plant and cement type and fineness required.

Chinese flagAs compared to a conventional separator or a ball mill with open circuit, third generation separator/classifier can reduce power consumption by 5 kWh/t-cement (NDRC, 2009. p.46).

Chinese flag Zhejiang Hushan Group Co.Limited installed a high efficiency separator/classifier in its 5000 tpd plant and reduced specific energy consumption in finish grinding from 36 kWh/t-cement to less than 31 kWh/t-cement. Annual electricity savings of 10 GWh (3500 tce) are realized - corresponding to annual production of 2 million t-cement (NDRC, 2009. p.47).

Chinese flag By installing a high efficiency separator/classifier in their 3700 tpd production line, Huaihai China United Cement Company Limited reduced specific energy consumption in finish grinding by 2 – 3 kWh/t-cement, resulting in annual electricity savings of around 4.2 GWh (1470 tce) (NDRC, 2009. p.47).

CO2 Emission Reduction Potential
Costs

Investment costs were estimated to be US $2/annual ton of finished material.

Indian flag For India, the investment costs are reported to vary between US $0.2-0.4 million, or around US $2 000 per ton or hourly capacity. 

Chinese flagInstallation of a high efficiency separator/classifier for a 5000 tpd production line in Zhejiang Hushan Group Co.Limited required an investment of 2 million RMB and took three months to complete. For annual output of 2 million tons of cement, the investment resulted in a payback time of less than one year (NDRC, 2009. p.47).

Chinese flagInstallation of a high efficiency separator/classifier for a 3700 tpd production line in Huaihai China United Cement Company Limited required an investment of 2.4 million RMB and took one month to complete. The system helped improve the product quality, increased output by 10%, allowed for increased use of cement additives by 5 to 10%, and reduced dust emissions. The payback time for the investment was less than one year (NDRC, 2009. p.47).

Parent Process:
Energy Savings Potential
CO2 Emission Reduction Potential

N/A

Costs

High-Efficiency Separators/Classifiers for Finish GrindingSchematic

High-Efficiency Separators/Classifiers for Finish Grinding Publications

Energy Efficiency Improvement Opportunities for the Cement Industry

The U.S. Environmental Protection Agency’s (EPA) energy guide, Energy Efficiency Improvement and Cost Saving Opportunities for Cement Making, discusses energy efficiency practices and technologies that can be implemented in cement manufacturing plants. This ENERGY STAR guide provides current real world examples of cement plants saving energy and reducing cost and carbon dioxide emissions.

Page Number: 

20-21

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: 

55-56

Page Number: 

46-47