Low Consistency Refining (LCR)

Application of low consistency refining right after first or second TMP stage and/or high consistence reject refining is a further development and holds important energy saving potential for softwood mechanical pulping. Key process parameters of the technology are:

  • very low specific edge load (0.4 – 0.6 Ws/m);
  • high stock temperature (around 85 C or higher);
  • very uniform feeding and controlled flow conditions (pressure, consistency, flow) (IPW, 2010, 24).

Moreover the production rate increases by 4% to 12%. The energy saving is due to the difference between refining response for LCR versus high consistency refining for a particular freeness range (Martin et al., 2000. p.24).

Development Status Products
Commercial

Low Consistency Refining (LCR)Costs & Benefits

Parent Process: Mechanical Pulping
Energy Savings Potential

The application of 100 to 200 kWh/t in LC refining can replace 200 to 400 kWh/t of high consistency refining at comparable freeness and tensile strenth (IPW, 2010. p. 24)
Energy savings by 142 kWh/t thermomechanical pulp can be achieved.
CO2 Emission Reduction Potential

CO2 savings by 16.3 Kg/t is estimated.
Costs

Low Consistency Refining (LCR) Publications

Immense potential for energy-efficient mechanical pulping

Date: 

2010

Format: 

PDF

Type: 

Publications

Published in the International Pulp and Paper Industry Magazine (IPW), this article by Andritz provides an overview of the technical offerings of the company that enable energy reduction in mechanical pulping applications.

http://spectrum.andritz.com/spectrum/article_ipw_042010.pdf

Page Number: 

24

Opportunities to Improve Energy Efficiency and Reduce Greenhouse Gas Emissions in the U.S. Pulp and Paper Industry

Format: 

PDF

Type: 

Publications

Published July 2000

http://www.energystar.gov/ia/business/industry/LBNL-46141.pdf

Page Number: 

21 & 24