Abstracts - VGB PowerTech Journal 4/2008

Role of 700°C Technology for Low-carbon Power Supply

Franz Bauer, Helmut Tschaffon and Dariush Hourfar

In face of climate change and the necessary carbon abatement strategy, the requirements for the future power supply are carbon-free technologies. Any scenario analysis provided by the IEA Energy Outlook or the publications of the European Commission on this field show the absolute need for carbon-based primary resources for the coming decades. Three major paths for carbon-free technologies were identified by the Technology Platform ZEP “Zero Emission Fossil-fuelled Power Plants”, i.e. post-combustion – capture of CO₂ out of the flue gas, pre-combustion – integrated gasification of coal in combination with CO shift and oxy-fuel – combustion of fossil fuel under oxygen atmosphere.

Highest Efficiency, Flexibility and Stability of Steam Power Plant Units by New Control Strategies

Shang Wei, Xiao Guotao, Liu Xiao, Thierry Bruneau and Klaus-Walter Wendelberger

Lower greenhouse emissions, smoother and more stable control performance, more flexible and accurate response to the grid dispatcher were the main goals to be achieved in the coal-fired Dingzhou power plant in China. The new control strategy is based on the well-known Siemens unit control module, which was extended by two new modules.

Improved Plant Operation by Updating the Control System - Experience from Two Grate-fired Boilers

Katarina Boman, Malin Nilzen, Mikael Nordlander and Monika Bubholz

During 2006 the control system in two nearly identical grate-fired boilers at the Boxholm plant in the south of Sweden has been tuned and updated using information from simulations of the system. The paper presents the modifications, the result in terms of improved operation as well as an analysis of the economical benefits.

The Norochcholai Power Plant Project (Sri Lanka) - An Example of Sustainable Economic Development by Utilisation of Seawater for Power Island and Emission Control

Elisabetta Carrea and Hubert Zimmermann

The paper describes how the Norochcholai project will meet Sri Lanka´s energy expansion programme by realising a 3 3 300 MW coal-fired power island using solely seawater for the power plant processes and auxiliary needs. The strategic project development approach towards a coal-fired power plant is outlined, followed by an overview of the core processes utilising seawater: desalination, demineralisation, on-site hypochlorite production and chlorination, seawater flue gas desulphurisation (FGD) and waste water management.

Current Status and Demand of Development of Stationary Fuel Cell Systems

Markus Blesl, Michael Ohl and Thomas Leipnitz

The different types of fuel cells suitable for residential heating and industrial CHP (combined heat and power production) are still in their pre-market phase. They have been tested in different kinds of pilot projects for different applications and with different fuels in different markets for several years. Reports are given on the experiences.

Synergies in Co-combustion of Biomass and Plastic Rich Solid Recovered Fuels

Matti Hiltunen, Petri Vesanto, Frank E. Mark and Martin Frankenhaeuser

The interest in using biomass as fuel has strongly increased. The available resources of wood fuels in Europe are not sufficient to meet the demand, and this pushes the market prices of wood even higher. The availability of biomass is often locally limited. At these conditions, the co-combustion of low priced plastic rich solid recovered fuel (SRF) and biomass is an attractive option to improve the economy of energy conversion in boilers that can technically use SRF and meet the environmental requirements without large investments.

Integrated Combined Heat and Power with Biomass Gasification and SOFC-Micro Gas Turbine

Lydia Emilie Fryda, Kyriakos D. Panopoulos and Emanuel Kakaras

Autothermal biomass gasification does not require an external heat source as it operates with air as gasifying medium and produces a gaseous fuel that after gas cleaning and conditioning can be used in solid oxide fuel cells (SOFC). Three combined heat and power processes able to integrate these technologies will be compared.

Small Steam Turbine without Gearbox - Increase in Efficiency at Part Load through Variable Speed

Jens Hampel

When low-output steam turbines are operated at high speeds, they require large gearboxes if they are to be connected to a generator for the production of electricity. Thanks to the use of modern frequency converters, the turbine can be directly coupled to the generator for high-speed operation. Functioning of such a system was demonstrated at the Dresden-Reick cogeneration plant, where a small, novel 500 kW turbine was installed in place of a steam-reducing valve.

Mobile Regeneration of Catalysts in Practical Probation

Herwig Maier, Gerhard Kirchgraber, Rudolf Wieland, Heinz Michele and Wolfgang Neuhäuser

A mobile system for regeneration of DENOX catalysts was developed. The system is carried by two separate large containers. A first system was delivered to the Altbach-Deizisau combined heat and power plant of EnBW Kraftwerke AG by the end of January 2007. Trial operation was successful followed by additional regeneration steps.

Long-time Experience with Deactivating and Regeneration of DENOX Catalysts and Evaluation with the Internet Database LEONID

Jürgen Brandenstein, Hans-Joachim Dieckmann and Heinz Gutberlet

The paper gives an overview over the long-term catalyst deactivation and the main reasons for catalyst aging. The chemical composition of de-activated catalysts provides information on the optimum catalyst regeneration process. The long-term deactivation behaviour of regenerated catalysts is compared to new catalysts. All characteristic catalyst features are listed in an online "LEONID"-database, developed by E.ON Engineering. The database provides the basis for long-term catalyst management of all connected SCR systems.

Analytical Aspects of Coal Characterisation, Evaluation and Properties

Herbert Prenzel, Anna Dux and Udo Wehmeyer

Coal and its combustion related properties are important in fossil-fueled power plants whenever the causes have to be determinded in connection with damage and load restriction. Fundamental knowledge of coal properties are required to solve such issues in a target-oriented and competent manner. The objective is to explain the wide range of coal properties based on their origin to give a complex overview of the testing methods and illustrate the process based requirements and related issues.

Online Moisture Measurement at Vacuum Band Filters

Lothar Hilbert and Johannes Mergl

The quality parameters of the FGD gypsum in the Lippendorf power plant were analysed during weekdays at the plant's laboratory. Due to operational reasons it became necessary to continuously check the current residual moisture with an online measuring device. The paper presents application and experience made with the moisture sensor applied.

RWE Power and Siemens Implement IEC61850 in Power Plant Auxiliary Power Supply

Jörg Ciuches and Robert Ostertag

RWE Power is currently building the two most modern lignite-fired generating units in the world at its Neurath site. The technical solutions are built upon the good results with the BoA technology (lignite-fired power station with optimised plant engineering) at the RWE Niederaußem power plant. One innovation is the direct integration of the electrical auxiliary power in the main C&I system technology utilising IEC61850 standards. For the first time with IEC61850, there is a standardised Ethernet and TCP/IP based solution in power distribution systems.