Comparison of Several Methods for Coal Fly-Ash Resistivity Determination.

The evaluation of fly-ash resistivity can be used for the optimization of E. P. 's parameters and to introduce some improvements for new plants. The aim of this work is to compare three different procedures which can be used to evaluate fly-ash resistivity: the in situ technique directly in the duct; measurement in laboratory of fly-ashes sampled at precipitator hopper and in the duct; estimating with a computer program based on experimental correlations. During the tests, the efficiency of E. P. has been related to the fly-ash resistivity evaluated with the three methods, which were found to be substantially equivalent. In the future, the efficiency can be known before the purchase of fuel and the price determined on this basis.