Biography
Biography: Patrick James Dale
Abstract
Ash fusion characteristics for a wide range of potential biomass fuels can be fully automated using image analysis techniques. Traditionally, ash fusion analysis involves heating pyramidal ash pellets in a furnace under oxidizing or reducing conditions to over 1500°C. Four characteristic behaviours over the temperature range are then identified, namely; ‘initial deformation’, ‘sphere’ or ‘softening’, ‘hemisphere’ and ‘flow’ temperatures. Whilst these temperatures are intended to help the operator predict boiler performance, they rely on visual observation rather than an objective physical measurement. Diff erences of up to 400°C have been reported for the initial deformation temperature of a single sample obtained from diff erent laboratories. A fully automated technique using image analysis has been developed that does not require manual interpretation and can provide a complete fi ngerprint of the behaviour of each sample. The relevance of these four temperatures will be discussed in detail as will the impact of improvements in furnace hardware and image analysis soft ware. A large test matrix of coals and biomass samples (including Russian, US and UK coals, hard and soft woods, and agrifuels) was tested to show how behavioural diff erences can be related to initial mineral composition whilst accurately predicting slagging and fouling potential.