Water and Energy Conservation in Stock Preparation for Paper Machines, 2006 Papermaker’s Conference

The paper industry and those supplying it are generally considered as being rather conservative when it comes to introducing new processes. When developing and designing new machines and production processes nowadays, consumption of water and energy play a major role. In the past, the common technique was so-called final treatment of the effluent water. Applying a suitable separation technique in the various sub-process stages becomes important in terms of

• total investment cost,
  
• operating costs,
  
• energy demand,
  
• overall losses, and
  
• recovery rate of fibers and fillers.

Awareness of customers’ "true" needs and a clear knowledge of the production process enable us to define new processes complete with integrated water cleaning equipment. The newly designed processes with internal separation equipment should attain

• further closure of the water circuits at
  
• reduced water consumption,
  
• maintain the process temperature, and
  
• increase the yield.

It is essential to involve all new technologies including membrane filtering techniques in setting up the process. The paper describes two different system set ups: one DIP and one OCC line, comparing energy demand, and specific water consumption.