CLEAN COAL TECHNOLOGY R, D&D

Significant achievements of European Coal and Steel Community R&D programmes in the development of clean coal power generation technology by A.J. Minchener and J.T. McMullan

Introduction

The European Commission has funded research on the production and use of coal, since the European Coal and Steel Community (ECSC) Treaty came into force in 1952. Financial support covered mining, coal preparation and conversion, and R&D in coal combustion and gasification. Since the end of the ECSC Treaty in 2002, R&D in the coal and steel area has been funded by the Research Fund for Coal and Steel (RFCS). The programme is managed by DG Research according to similar principles to those applied to the ECSC Programme, but with new guidelines. The areas of emphasis in this review are coal combustion and gasification. Here, in the 1970s and 1980s, there were major programmes to develop coalbased alternatives to oil and gas, in response to the oil crises of the period. After the start of the 1990s, the main focus became the development of clean coal technologies for power generation.

ECSC R&D achievements in coal-fired power generation

Most ECSC R&D was undertaken via collaborative projects. This report highlights some of the major achievements, and the topics emphasised are:
Improving the performance of pulverised coal fired power plant 
Here, work was undertaken to improve performance through: prediction and minimisation of the impact of coal blends on combustion, individual burner characterisation, and improving PC airflow distribution, measurement and control. The work was carried out through laboratory and large scale testing, the development of combustion models, plant optimisation studies, development of on-line monitoring techniques, and improved operational control strategies.
Reducing slagging and fouling for pulverised coal fired plant
This had three main themes: fundamental studies to improve overall understanding of the processes of ash deposition, probes and predictive tools to enable the measurement of deposition extent, and supporting studies to reduce ash deposition in large-scale PF boiler plant. The programme has generated a wealth of information and has considerably extended the understanding of the mechanisms and processes of ash deposition.

Improved environmental control for pulverised coal fired plant

This work has been very successful. It was shown that careful selection of combustion modification techniques could result in significant reductions in NOx emissions. A range of measures have been established, including low NOX burners, air staging, flue gas re-circulation, and re-burning. Overall, this has led to a number of techniques that have been applied by EU industry, both within the European Union and in external markets.

Co-combustion and fluidised bed applications

The programme supported key projects to address many important co-utilisation issues. These included practical laboratory and pilot scale tests of coal combustion with natural wood, agricultural waste, paper waste, agroindustrial waste, waste edible oils, refuse derived fuel (RDF), plastic waste, meat and bone meal (MBM), and sewage sludge. Most of the work focused on CFBC applications as this technology is particularly suited to co-firing applications.

Valorisation of coal processing residues

The ECSC Programme supported various initiatives to minimise the impact of such coal residues, together with coal mining wastes, by characterising these materials and evaluating them for their potential applications. This included techniques to utilise the energy content of such residues, both to ensure comprehensive utilisation of resources and to achieve a significant environmental benefit. Advanced power generation In accordance with the ECSC terms of reference, the majority of the projects on advanced power generation focused on activities offering prospects of demonstration and replication of the technology under development. The results from these research activities contributed a significant part of the R&D achievements in the field of coal utilisation. As such, they enabled European industry, through co-operation at Community level, to make significant progress in the development and introduction of advanced power generation systems.

Control of CO2 emissions

Some initial work was undertaken within the ECSC Programme, which considered both PF and IGCC processes. The emphasis was on separation membranes, and on coal reactivity studies. Since the end of the ECSC programme, it has been recognised that IGCC may be the technology of choice when CO2 mitigation becomes a necessity. Consequently there has been an upturn in interest in methods for gas separation and this topic is of key importance in the ongoing RFCS programme and in the EC supported Framework R&D Programmes.

Exploitation of R&D results

The results arising from the ECSC coal utilisation R&D Programme have played a key role in the development of clean and efficient coal-based power generation. Work on PF combustion has contributed greatly to improving the performance of existing units within Europe, and has assisted in the deployment of newer designs of plant, with advanced steam cycles and state of the art environmental control systems.

Similarly, with CFBC, the ECSC work has greatly assisted in the full understanding of the process, leading to improved designs of plant capable of burning a wide range of coals and alternative feedstocks in an efficient and environmentally acceptable manner. For IGCC, the ECSC work led to the construction and operation of various pilot plants, from which two complete large-scale demonstration plants were installed in Europe. Subsequently, considerable support work was provided through ECSC, including component development and process measurement methods.

The way forward via the RFCS programme

The Treaty establishing the ECSC expired on the 23 July 2002. The ECSC funds were transferred to the European Community to create a common fund for research in the coal and steel area. This is being used to support the 'Research Programme of the Research Fund for Coal and Steel', which is managed by EC DG Research according to principles similar to those of ECSC RTD. The RFCS programme began in 2002, and the first projects are still underway, with the level of results yet in the public sector being very limited. Accordingly, a listing of the clean coal power generation R&D activities currently underway is included in Appendices B and C, which include the contact details of the research organisations and a brief description of the work, so that specific follow-up can be undertaken as required by interested organisations.

Full report can be downloaded HERE