Abstracts - VGB PowerTech Journal 3/2009

CO₂ Capture and Storage in the Framework of Economic, Technical and Political Challenges

Bernhard Fischer, Jörg Kruhl and Peter Radgen

The future energy supply is confronted with huge challenges to reduce its impact on the anthropogenic greenhouse gas emissions. Efficient sustainable coal-fired power stations are important for the future energy mix. The demonstration of the 700 °C technology, the pilot plant fleet to test different CO₂ separation processes as well as the demonstration of power plants with low CO₂ emissions due to CO₂ capture are the most important steps towards sustainable coal-fired power plants.

50 Plus – At Full Speed to the Coal Plant  of the Future

Andreas Willrodt and Helmut Tschaffon

As the first company worldwide, E.ON Kraftwerke is planning a hard coal-fired power plant with over 50 percent efficiency at the Wilhelmshaven site, within the scope of the “innovate.on” technology initiative. The demonstration power plant should have 550 MW power output and start operation in 2014. To achieve the high efficiency, the live steam temperature particularly must be raised to 700 °C and the corresponding pressure to 350 bar, respectively. The increased strength requirements owing to the 700 °C technology should be solved with nickel-based materials.

Status of Planning for Steam Generators  in the 800 MW Class

Michael Schütz, Rolf Hauk and Georg-Nikolaus Stamatelopoulos

Within the scope of its power plant modernisation programme RWE Power plans the construction and operation of a 2 x 800 MWel power plant in Westphalia, Germany, and in Eemshaven, The Netherlands. The applied technology and the size were optimised according to technical and economic criteria.
CO2 Capture and Storage in the Framework of Economic, Technical and Political Challenges

Bernhard Fischer, Jörg Kruhl and Peter Radgen

The future energy supply is confronted with huge challenges to reduce its impact on the anthropogenic greenhouse gas emissions. Efficient sustainable coal-fired power stations are important for the future energy mix. The demonstration of the 700 °C technology, the pilot plant fleet to test different CO2 separation processes as well as the demonstration of power plants with low CO2 emissions due to CO2 capture are the most important steps towards sustainable coal-fired power plants.

50 Plus - At Full Speed to the Coal Plant of the Future

Andreas Willrodt and Helmut Tschaffon

As the first company worldwide, E.ON Kraftwerke is planning a hard coal-fired power plant with over 50 percent efficiency at the Wilhelmshaven site, within the scope of the "innovate.on" technology initiative. The demonstration power plant should have 550 MW power output and start operation in 2014. To achieve the high efficiency, the live steam temperature particularly must be raised to 700 °C and the corresponding pressure to 350 bar, respectively. The increased strength requirements owing to the 700 °C technology should be solved with nickel-based materials.

Status of Planning for Steam Generators in the 800 MW Class

Michael Schütz, Rolf Hauk and Georg-Nikolaus Stamatelopoulos

Within the scope of its power plant modernisation programme RWE Power plans the construction and operation of a 2 x 800 MWel power plant in Westphalia, Germany, and in Eemshaven, The Netherlands. The applied technology and the size were optimised according to technical and economic criteria.
For the new convoy plants a broad fuel range is specified on the basis of imported hard coal. Steam pressure and temperature are increased to the values corresponding to the latest state of the art, so that the advantages of the developed advanced materials can be used. Given these high steam parameters the use of austenitic materials with high chromium content in the convection heating surfaces is absolutely required.

Use of an Innovative Measuring Method for Heavy Metals in Wet Flue Gases Downstream of FGD

Johannes Mayer and Hans-Jürgen Dieckmann

During co-incineration of waste and sewage sludge in coal-fired power plants emissions of heavy metals have to be determined according to the German 17th Ambient Air Control Ordinance. The existing sampling method according to EN 14385 was modified on the basis of a VGB R&D project to improve manual PM measurement techniques in wet flue gases by use of a heatable particle filter in an in-stack position (inside the wet flue gas duct) that was heated up to a temperature significantly above the water and acid dew point. This modified sampling train with heated in-stack filter was compared with the original standard reference method EN 14385 with filter in out-stack position.

Recovery of Process Water from Cooling Tower Blowdowns

Andreas Wied and Axel Haake

Thanks to innovative process technologie, today's treatment and recycling concepts have become exceedingly attractive not only from a technological but definitely also from an economic point of view. The paper describes an advanced method for reusing reclaimed water in power plants on the basis of a project implemented by WAT-membratec® GmbH & Co. KG. It concerns the re-use of waste water from cooling tower blowdowns. Purpose of the preparation in this specific project is to purify and desalinate the waste water coming from the cooling tower blowdowns and re-use it then as additional water for the boiler feed water plant placed in the power plant. The recycling plant mainly consists of a membrane-based equipment concept including an ultra-filtration system with downstream reverse osmosis.

Automatic Quality Assurance of On-line Water-steam-cycle Analysis as Part of the Ensdorf Power Plant Renovation Process

Thomas Brück and Pedro Isliker

The requirements placed on analytical systems have increased significantly in recent years. As a result the quality assurance functions, particularly in the areas of evaluation, monitoring, hardware testing and signal transfer have significantly developed further. A locally installed computer with a quality assurance program was installed in the Ensdorf power plant. Access to the database in the computer is also possible from an external system, so that the information is also available to the power station control system for process control and visualisation.

New Challenges for the Deposition of the Flue Gas Desulphurisation Product of the Dürnrohr Power Plant

Gerald Kinger, Manuela Dissauer, Christine Faustmann and Werner Schöngrundner

At the Austrian Dürnrohr power station a flue gas desulphurisation plant according to the spray absorption process is being operated. The FGD product is deposited on the site of the power station. In 2008 the legal conditions changed, i.e. the EU Directive (1999/31 and 2006/12) had to be transposed into national law, and the currently used landfill site could no longer be used. Hence a new landfill had to be planned. The new planned site was the first project which was approved according to the new regulation in Austria.

Removal of NS Compounds from FGD Waste Water by Nitrilysis

Erik Flemming Smitshuysen, Niels Ole Knudsen and Folmer Fogh

The formation of NS compounds is an integrated part of the oxidation chemistry in wet flue gas desulphurisation (FGD) plants and they contribute to the nitrogen content of the associated effluent. However, these compounds also contribute to the undesired nitrogen freight in the waste water. Elsam, no belonging to Vattenfall A/S and DONG Energy Power, developed a technique to reduce the SN compounds which are oxidised into nitrates and sulphates.

Lithium Hydroxide - A Promising Alternative for the Solid Matter Alkalisation of Boiler Water

Eva-Maria Graß and Ullrich Teutenberg

Chemical operation of the Dresden "Nossener Brücke" gas turbine CHP station is being presented. The paper summarises the experiences and results of various alkalisations of the steam boiler plant. With the commissioning of the plant in 1995, solid matter alkalisation with sodium hydroxide and volatile alkalisation with ammonia were performed. At the end of 1995 operational troubles were detected on the economiser and the evaporator finned tubes caused by strong local selective leaching. As a consequence, the chemical mode of operation was shifted to AVT treatment that was stopped for good due to further problems. Since then the heat recovery steam generators have been treated with ammonia and lithium hydroxide. This mode of operation yielded positive results.

Organic Boiler Feedwater Additives Based Upon Film Forming Amines

Wolfgang Hater and David Olivet

Film forming amines have been successfully used as feedwater treatment additives for several decades, especially in the field of industrial power plants. The data of new investigations on their properties and the results of a field trail are intended to fill the gaps in the knowledge about film forming amines, in order to finally introduce this technology into the corresponding guidelines for the treatment of steam generators. Finally the results of a field trial at a combined heat and power plant will be presented.

Influence of Corrosive Atmospheres on the Properties of Refractories in Operation of Waste Incineration Plants

Thomas Tonnesen and Rainer Telle

The corrosion mechanisms of different refractories in operation of waste incineration plants are presented. A testing method in steam atmosphere according to ASTM was used to determine the oxidation resistance. The experiments at 1000 °C proved an excellent stability in shape dimensions of the refractories and low volume change below 1 %. Furthermore vapour phase corrosion experiments with SiC mortars and evaluation of slag corrosion tests of high alumina bricks after use in a waste incineration plant have been performed.

Condition Monitoring for Turbines and Generators for Sure! But what's about the Auxiliary Units?

Roland Schuhmann

The techniques and strategies for monitoring the condition of large turbo machinery in power plants and also chemical process industries are well known and different hard- and software products are available. The paper gives an overview - from the point of the BASF Ludwigshafen site - about the possibilities to monitor condition also for the smaller machinery in an efficient way. The outlook shows the trends for the future to monitor our plants and what visions we - as a company which operates many plants - have to do this in an efficient way.

VGB Instruction Sheet M 216: Recommendations for the Design, Properties and Condition of Waste-fired Boilers

Gerold Wittek and Ulrich Schirmer

The VGB Working Panel "Thermal Waste Utilisation" is in charge with the VGB Instruction Sheet M 216, entitled "Recommendations for the Design, Properties and Condition of Waste-fired Boilers" that is currently being revised completely. The structure of the Instruction Sheet and the current state are being outlined. The new Instruction Sheet addresses orderers and suppliers of waste-fired boilers and describes the typical designs, properties and conditions of waste-fired steam generators.

Analytical Investigation on Thermo Mechanics of Precast Refractory

Sascha Krüger and Michael Beckmann

Precasted refractories (e.g. SiC tiles) are used in waste-to-energy plants and refuse-derived fuel plants due to their good chemical stability and physical properties (high hardness, heat conductivity and gas tightness). The materials suffer from stresses and reversible deformations when the wall is exposed to thermal load. These stresses occur due to temperature gradients in the material and due to different thermal expansion coefficients of the materials (metallic membrane wall and ceramic refractory). The unavoidable thermal expansion of the materials leads to mechanical stresses if free elongation is opposed by the type of construction. The paper describes a simplified mathematical model, which allows estimation of stresses and calculation of deformation of the ceramic refractory operated at steady state.