Green Liquor Clarifier #1 Performance Evaluation of McFarlen Engineering Ltd.
ClearFlow™ Feedwell and Bustle Pipe Design Donna Hohertz – Process Specialist
Introduction:
Eurocan Pulp & Paper in Kitimat, BC operates two green liquor clarifiers. In late 2004 it was decided #1 green liquor clarifier needed to be replaced. During the construction phase the opportunity arose to use a new ClearFlow™ feed well and bustle pipe system developed by McFarlen Engineering Ltd.
Eurocan Pulp & Paper and McFarlen Engineering signed a process guarantee stating the new design would give 10% better green liquor clarity versus the existing technology.
Executive Summary:
The new feedwell and bustle pipe system was evaluated for a period of one month (Jan. 1st to 31st, 2005).
The new design (#1 clarifier) has demonstrated the following when compared to the old design (#2 clarifier):
- 26% better green liquor clarity
- 43% better green liquor clarity with the use of polymer (Powerfloc 363)
- 16% better clarity without the use of polymer (Powerfloc 363)
- The process guarantee has been fulfilled.
Experimental Methods:
Green liquor samples before the clarifier, after #1 clarifier, after #2 clarifier and the combined flow into the slaker were collected once per shift by recaust personnel. Samples were tested for solids content by the main lab process technician using Eurocan ISO procedure TSM-P-10.