Assessment of Ash Re-firing and Mineral Addition - Impact on Plant Performance and Ash Disposal

Abstract:

<p>This document is the final report for the project titled 'Assessment of Ash Re-firing and Mineral Addition - Impact on Plant Performance and Ash Disposal'.</p> <p>Pulverised coal fired generation plant will continue to play a major role in the world-wide electrical power market for the foreseeable future. Emission standards have become tighter in recent years and coal fired plant has been required to become more flexible in terms of operating regimes. The changes have led to increases in the levels of unburnt carbon in ash, deposition patterns in boilers as well as increased pressure on the performance in electrostatic precipitators.</p> <p>This project, to investigate if ash refiring and mineral addition were viable methods of improving boiler efficiency and reducing emissions, was supported by the DTI as part of its Cleaner Coal Programme. The project involved the collaboration of two generators (RWE npower and TXU Europe), a major coal supplier (UK Coal) plus two university groups (Imperial College London and the University of Sheffield)</p> This report has a summary and is divided into the following sections: <ol> <li>Introduction</li> <li>Project Overview - Aims, objectives and work programme</li> <li>Coals and minerals selected for the project</li> <li>Mineral addition trials on the Entrained Flow Reactor</li> <li>University of Sheffield MSc projects</li> <li>Pilot scale trials of ash re-firing</li> <li>Pilot scale trials of mineral additions</li> <li>Characterisation of coals, ashes, minerals and deposits</li> <li>The nature of fly ash and its ability to be collected in electrostatic precipitators</li> <li>Power station evaluation of ash re-firing</li> <li>Techno-economic assessment</li> <li>Conclusions</li> <li>List of Participants</li> </ol>

Author(s):

Riley, GS, Beeley, T, Williamson, J, Wigley, F, Russell, NV, Zandi, M, Ricketts, B & Cooper, PR