Abstracts - VGB PowerTech Journal 12/2013

VGB Congress “Power Plants 2013” – Report and opening speeches

The VGB Congress “Power Plants 2013” took place in Masstricht/NL from September 25 to 27, 2013 under the motto “Security of Supply – From Challenges to Solutions”. Experts from 31 countries attended the largest European congress for power and heat generation to discuss and inform about current issues. The congress comprised the sections “Security of Supply: A Common European Challenge“, “Technical Solutions for our Future Electricity Generation”, “Operational Experience as Key Competence” and “Thinking Ahead: Projects and Visions 2020+” where participants and lecturers dealt with the future challenges of European power supply.

CO₂ capture with MEA (monoethanolamine) for lignite-fired power plants

Sandra Schmidt and Peter Moser

In RWE Power’s Coal Innovation Centre at Niederaussem innovative technologies for lignite fired power plants are developed and tested that represent a significant step for ward in comparison with state-of-the-art technologies. In July 2009 the first post-combustion capture pilot plant (PCC) at a coal-fired power plant in Germany was commissioned. Before testing new solvents in the capture plant, MEA (monoethanolamine) was used as a benchmark CO₂ solvent to investigate characteristics of the plant, operation behaviour and its process performance. Also the prediction accuracy of the process simulation tools can be validated.

Turbulence in energy market – Energy management system helps to avoid rocks

Heidi Heikkinen, Jukka Saarinen, Henri Särkilathi and Martin Wortel

The production of industrial and municipal power plants must be optimised in order to maintain the plants profitable. The result of the optimisation is an optimal usage of the production components which advices the operators how to satisfy power consumption. The profitability of the power plant can be improved by reducing costs and increasing profits, and therefore a modern energy management system (EMS) can be a crucial part of the power plant. TOPi® EMS of Fortum is designed for production planning and optimisation.

Coal combustion products – A global perspective

Craig Heidrich, Hans-Joachim Feuerbornand Anne Weir

Large-scale use of coal in power generation gives rise to significant quantities of coal combustion products (CCP) from which important “hard won” end use markets have been established. Current global CCP production and utilisation including volume and value of international trade will be discussed. An overview of country-specific classification systems for CCPs will be discussed, moreover the important role of legislation in creating legal certainty for the ongoing investment in CCPs management and market development.

The value proposition of circulating fluidised bed technology for utility power sector

Robert Giglio

Circulating fluidised bed combustion (CFBC) has been demonstrated commercially at the 500 MW plant at the Lagisza site in Bedzin, Poland. Besides being the largest operating CFB steam generator in the world, the CFB at the Lagisza plant has unique first-of-a-kind design features. The plant also meets all air emission permit levels without any post-combustion DENOX or FGD. Declining world market coal qualities are also easily combusted. The paper also provides an overview on future coal supply, its qualities and prices.

Large-scale 100 % wood conversion with low-NOx values

Xavier Henry, Frédéric Mercier and Paolo Cavezzale

The Max Green project in Rodenhuize, Belgium comprises conversion of the Rodenhuize unit 4 from coal combustion (262 MWe) into 100 % wood pellets combustion. With this conversion, the emission limit could only be achieved by secondary measured for reducing NOx requiring installation of a DENOX system. The SCR as part of the Max Green Project was realised successfully as a result of a specific design based on a dedicated research programme, the excellent cooperation between customer and contractor and the good management of the interfaces between boiler and SCR.

Investigating the influence of low load operation on the requirements of the catalyst typology, ducts arrangement and boiler efficiency

Marianna Zeppieri and Marco Vittorini

Coal-fired power plants are among the major emitters of air pollutants, and it is a main and challenging task to adjust existing coal-fired power stations to the EU directive mainly regarding NOx emissions which can be controlled by boiler combustion (primary NOx control) or post-combustion flue gas treatment (secondary NOx control). The paper presents the retrofit of an SCR system at an existing Enel power plant. Critical aspects are highlighted and the most important design parameters to be considered when retrofitting an SCR are being analysed.

SCNR technology for large combustion plants – Operational experiences with a commercial installation in a 225 MWel coal-fired boiler

Wolfgang Schüttenhelm, Karlheinz Huberand Zoltan Teuber

Compliance with new and more stringent NOx emission control limits for hard coal- and lignite-fired units, co-firing of new fuels such as biomass and increased operational flexibility are requiring highly efficient but nonetheless cost-effective emission control technologies. The paper presents ERC’s most recent SNCR installation for large combustion plants in East Europe including the operational experiences gathered yet. It will be demonstrated that SNCR is an attractive option for retrofits and new plants of this size.

Replacement of an SCR DENOX system by a highly efficient SNCR in a waste-to-energy plant in the Netherlands

Frans Moorman, Bernd von der Heide and Claus Stubenhöfer

In recent years the SNCR technology in Europe has made great progress, particularly in the field of smaller combustion plants fired with municipal waste, RDF, bio mass etc. A Dutch waste-toenergy (WtE) plant consisting of three incineration lines has been operating since 1996. Within the scope of retrofit measures, the operator decided to replace the existing SCR systems with the SNCR technology because of the favourable cost-benefit-ratio. All three systems are running with very low NOx emission values fully meeting the customer´s expectations.

Visualisation of dust collection and re-entrainment in a pilot-scale electrostatic precipitator

Muhammad Majid, Adrian Dobrowolski, Helmut Wiggers and Peter Walzel

According to the Technical Instructions on Air Quality Control (TA Luft) dated to 30 June 2002, more stringent emission limit values have to be met for particulate matter thus increasing the requirements of electrostatic precipitators (ESP). The ESP efficiency can be improved by recirculating the gas. Here, a part of the precipitator outlet with high dust concentrations is re-mixed to the precipitator inlet. The aim of this work is the visual examination of the particle concentration distribution across the duct width of a pilot-scale ESP. Thus, the areas with high particle concentration should be identified to optimise the recirculation design.

Effect of chloride transients on the corrosion behaviour of low alloyed steel in cladding flaws of reactor pressure vessels under oxygenated high-temperature water conditions

Martin Bojinov, Erika Nowak, Michael Stanislowski and Timo Saario

Strain-induced corrosion cracking in low alloy steels (LAS) has been extensively investigated during the last decades. One finding from recent investigations is the detrimental role of even small amounts of chlorides, which has been shown to increase the cracking susceptibility of LAS. In order to evaluate this finding, a demanding research programme has been established.

Technical principal of a pressure balanced expansion joint

Reto Löhrer, Peter Bieri and Udo Dudziak

In 2012 the Bremen waste incineration plant was considerably modernised. The operator swb purchased a new steam turbine which resulted in an increase of power from 15 MW to 50 MW. A DN 3300 axial universal expansion joint from kompaflex ag was placed directly after the axial exhaust steam pipe to compensate thermal movements in axial and lateral direction. The installed pressure balanced expansion joint performs its job flawlessly.