Design and preliminary testing of an experimental system for ash deposition studies

A long term effort by the University of Tennessee Space Institute for ash deposition studies in the United States Department of Energy Coal Fired Flow Facility (CFFF) Boiler includes an experimental program with the aim to develop information on how coal ash constituents and operating conditions influence ash deposition and soot-blowing effectiveness in a coal-fired magnetohydrodynamic power generation system.

Towards this effort, an experimental deposition probe has been designed to measure ash deposition rates and also to measure sootblowing effectiveness. The deposition probe has been designed, fabricated and installed in the CFFF super heater inlet. This probe has been tested for a limited time, and following some development problems, it has been found to operate well. Also a system has been developed to monitor and record the ash deposition behavior over an extended time based on a one and two television camera and VCR recording system.

Also a sootblower has been speciflcally designed for blowing the deposition off the deposition probe which enables the study of the effectiveness of sootblowing in controlling ash deposition by varying different parameters of sootblowing. The sootblower remains to be tested.

Both the ash deposition probe and the sootblower for the deposition probe were made from existing CFFF water-cooled gas sampling probes, after making certain modifications. The designs are simple, proven, capable of serving in very high temperature gas stream and are very cost effective.