Development of a video-based slurry sensor for on-line ash analysis. Technical progress report, third quarter, April 1, 1995--June 30, 1995

Automatic control of fine coal cleaning circuits has traditionally been limited by the lack of sensors for on-line ash analysis. Although several nuclear-based analyzers are available, none have seen widespread acceptance. This is largely due to the fact that nuclear sensors are expensive and tend to be influenced by changes in seam type and pyrite content Recently, researchers at VPI&SU have developed an optical sensor for phosphate analysis. The sensor uses image processing technology to analyze video images of phosphate ore. It is currently being used by Texas gulf for off-line analysis of dry flotation concentrates. The primary advantages of optical sensors over nuclear sensors are that they are significantly cheaper, are not subject to measurement variations due to changes in high atomic number minerals, are inherently safer and require no special radiation permitting. The purpose of this work is to apply the knowledge gained in the development of an optical phosphate analyzer to the development of an on-line ash analyzer for fine coal slurries. During the past quarter, a new prototype sample presentation system for the optical analyzer has been developed. This new approach appears to solve the problems encountered with previous prototypes. A qualitative comparison of the images obtained with the new system and those obtained with the previous prototypes indicates that the new system provides much smoother, clearer images. The new sample presentation system is currently being integrated with the image analysis computer and a patent disclosure has been filed with the university