Abstracts - VGB PowerTech Journal 1-2/2006

European Research and Development Strategy for Clean Power

Rolf Linkohr

Strategy does not mean that you know in advance at what position you have to be at a certain point in time. It rather means to be properly positioned right on time. Industry, public bodies including the EU have to co-operate closely. In this context it also has to be understood that energy also means foreign policy. Besides, it is vital for a secure energy supply that a consensus is achieved among all social groups involved.

Power Plant Technology Based on Fossil Fuels

Reinhardt Hassa, Heinrich Breuer and Udo Gadget

The production plants in East Germany went through a radical change process. Approximately 8 billion € have been invested in these processes up to 2001. The specific CO2 emissions could be reduced in this period by almost 25 %. Although uncertainties exist in connection with investment decisions due to varying electricity tariffs, Vattenfall decided to design new coal-based power stations in Germany. Vattenfall’s long-term commitment regarding the generation of electricity from coal is documented amongst other things by a pilot plant project based on the Oxyfuel principle.

EPR Project for Flamanville 3

Robert Pays

In accordance with the French energy act and in order to keep the nuclear option open, enabling it to decide whether to replace existing nuclear reactors when the time comes, EDF now wants to start building the first-off EPR reactor at Flamanville. The design principles retained for EPR are based on an evolutionary concept relying on mastered technologies supported by more than 1300 reactor years of experience feedback in France and Germany. The EDF engineering division manages the construction project acting as architect engineer and working in close co-operation with manufacturers.

Fuel Mix and Management

Klaus Nadolny and Manfred Boers

With the German mining industry on the decline, imported coal now accounts for more than 50 % of the steam coal market and this has meant a significant increase in fuel quality requirements. Ideally, power station engineers, purchasing agents and waste management services should be working with the fuel suppliers right from the word go – beginning at the power station design phase. Only by adopting an overall plan for the provision of a homogenous fuel blend, which takes account of changes in sourcing structures, it will be possible to ensure a quality-compatible supply of coal in the long term.

First Experience with the Emissions Trading Scheme

Bernhard Fischer and Jörg Kruhl

The new emissions trading system has been in place since 1st January 2005. Our practical experience to date of the application and allocation processes for emission rights indicates that, unless the system is made much simpler, it will self-strangulate in red tape. The allocation rules must be made clearer, simpler, and more transparent. All market participants were surprised by the price trends in the market for the trading of CO2 emission rights. International initiatives – to increase the efficiency of electric generation in other parts of the world – need to be part of a global cost-minimisation strategy.

The Off-shore-concept Multibrid M5000

Niels Erdmann

The wind energy converter Multibrid M5000 with an installed capacity of 5 MW was designed for off-shore application. Therefore, special attention has been put on high reliability and the specific ambient conditions were consequently considered. The prototype was installed in November 2004 and commissioned during the following months. With now one year of operation the determined operating data confirm the high expectations concerning the concept. Follow up projects are being prepared.

Significant Cost Reduction and Clear Increase in Revenues at a 30-year-old Site through the Concept of Optimised Phased Modernisation

Michael Lux and Joachim Rutschmann

At the Völklingen-Fenne site, STEAG Saar Energie AG operates two combined heat and power plants and one heat supply plant, as well as the world's largest mine gas-fuelled engine plant and a gas turbine for the production of electric power and district heating. Following the liberalisation of the power market, timely modernisation measures were initiated in order to ensure that the 20, 25 and 30-year-old power plants remain competitive. The aims of the extensive modernisation work were principally to significantly improve the cost situation of the whole site and to increase revenues through greater flexibility – both decisive factors in achieving sustained success in liberalised markets.

Optimisation of the Fuel to Air Ratio at Single Burners by an Exact Measurement of Coal Dust and Air

Björn Reese and Hans Georg Conrads

Due to the increased demands for efficiency and emissions, a far-reaching optimisation of the combustion processes becomes essential for existing power plants as well as for future projects. A very high potential lies in the control of the specific fuel/air ratio at each individual burner. By precisely controlling the fuel/air ratio at each individual burner, the combustion process in the furnace is also being controlled which has positive effects on the operation quality as well as the reliability of the whole boiler of a power plant unit. The Mecontrol measuring system is supporting the process.

Life Time Extension of DENOX Catalysts by Ultrasound Regeneration

Maximilian Ebinger and Alexander Schluttig

The prolongation of the life time of DENOX catalysts with the same technical safety and availability enables considerable economic saving potentials in coal-fired power stations and waste incineration plants. The activity of spent DENOX catalysts will be increased to the standard of brand-new ones by ultrasound regeneration adapted to the needs. SO2/SO3 conversion rates will be decreased to the standard of brand-new catalysts. Ultrasound regenerated catalysts have the same qualities as brand-new ones. The economic and technical conditions for an adapted to the needs ultrasound regeneration will be described as a basis of profitable change strategies with a high cost reduction potential.

Technical and Economic Advantages by Using Secondary Desulphurisation Combined with a CFB Boiler when Burning High-Sulphur Content Coals

Winfried Notter, Stefan Ahman and Joachim Seeber

When firing high-sulphur coals in power plants a very high SO2 separation efficiency has to be reached to meet the most recent EU emission standards. By the combination of primary desulphurisation in the fluidised bed with an NID system developed and patented by ALSTOM the direct SO2 separation in the fluidised bed can be reduced to approximately 90 % depending on the limestone quality. As a consequence, an overdosing of limestone is minimised and the required emission limits can be safely kept as well for limestones with a low or medium reactivity.

Evaluation of the Application of Thermosleeves

Axel Schulz, Jürgen Sydow, Robert Wernicke, Thomas Hahm and Steffen Wussow

The operating experiences of the last years have demonstrated that the thermosleeves that had been inserted for the protection of sensible pipe and vessel nozzles suffered from damage. The paper will analyses the situation by taking a feed nozzle of an emergency and cooling line. The possible root cause for the damage will also be revealed under the aspects of tension levels.

The Risk-based Maintenance Concept – European Development and Experience in Implementation on High-temperature Steam Piping

Jörg Bareiß, Eberhard Roos, Aleksandar Jovanovic, Miodrag Perunicic and Daniel Balos

Maintenance with its significant impact to the operating costs of a plant becomes the key point in the liberalised energy market. A current solution offered by risk-based procedure links the probabilities of failure (damage, disturbance) with consequences resulting from it (damage extend, relevance of the outage) and ensures that economical aspects are also considered. An industry-independent risk evaluation method for the inspection and maintenance planning is presented. The new method was applied to high-temperature boiler and piping components under internal pressure as well as to the damage mechanisms creep and fatigue.

Potentials of Two-phase Flow Simulation in the Case of FGD Spraying Towers

Markus Feldkamp, Hans Fahlenkamp, Christian Moser and Theo Risse

Modern lignite- and hard coal-fired power stations comprise a flue gas desulphurisation plant (FGD), where the air pollutant sulphur dioxide (SO2) is absorbed in a spraying tower. Potentials for optimisation of existing and new FGD scrubbers are offered by fluid dynamics, particularly within the wall area of the spraying scrubbers. The simulation of the two-phase flow, concerning flue gas and washing suspension, offers a matured durable possibility to illustrate flow conditions. It is an objective to show and to evaluate possible changes in the flue gas flow as consequence of retrofitting measures, with the help of a founded and above all validated simulation model.

Modern Fire-fighting Techniques in Power Plants

Walter Grossoehmig

The current age structure of the German coal-fired power plant portfolio leads to the conclusion that operators ought to invest into state-of-the art risk management with automatic protection mechanisms. Solutions have to be identified how to combat possible fires through the introduction of modern fire-fighting techniques that should be reconsidered and its introduction should be accelerated.