On-Line Video Sensing of Surface Dirt on Pulp, 1994 Process & Product Quality Conference Proceedings

R. E. Popil, K. C. D. Houston, K. R. Wilson <>

Dirt level in bleached market pulp is a major quality factor which demands significant mill resources for characterization. In the past decade, image analysis technology has become easily accessible for a wide variety of applications using inexpensive PC microcomputer hardware and software. MacMillan Bloedel Research has developed a video imaging system for the purpose of continuous on-line monitoring of pulp dirt for quality control and assurance at the Harmac pulp mill. The system uses diffuse stroboscopic illumination, high magnification, and custom written software to produce microscopic resolution binary images of surface contaminants, statistics and continuous scrolling trend plots of the dirt contaminant level. The paper discusses the principle of operation, the software algorithm, and the correlation of the on-line data acquired since 1989 with standard off-line manual testing data.