Abstracts - VGB PowerTech Journal 6/2008
State of CO2 Separation from Fossil-fired Power Plants
Reinhardt Hassa
CO2 separation comprises increase of efficiency of individual power plant systems, improvement of the efficiency of power plant units as well as removal of CO2 emissions from the combustion process. All these activities are standing in a new light through the decision of the European Commission of March 2007. According to that decision the CO2 emissions are to be reduced by 20 % until 2020 und by 60 to 80 % until 2050. These objectives have to be achieved under the aspect of supply security that has to be guaranteed also with fossil fuels.
Considering the Needs of Maintenance when Constructing New Power Plant Units
Gereon Thomas
“Considering the Needs of Maintenance when Constructing New Power Plant Units“ is the title of an instruction sheet published by the VGB Committee “Maintenance Management”. It should be used as a check-list by the planning engineer and the owner of a power plant to be constructed in order to consider all aspects important for effective maintenance and repair during plant operation.
Experience with Corrosion Processes at Steam Generators of the Lippendorf Power Plant – Strategy to Eliminate Existing Damage and Measures to Expel Damage Mechanism
Joachim Kahlert, Frank Wutzler and Peter Lange
In the Lippendorf power plant corrosion damage at the evaporators as well as tube damage was detected in 2004. Sulphide-induced high-temperature corrosion was identified as root cause. After comprehensive investigations it was possible to find an operation mode that widely expels corrosion mechanisms.
Experience with Protection and Restoration Measures on Reinforced Concrete Structures
Dieter Lehnen, Titus Klöker, Joachim Meyer and Peter Holdt
Often measures of protection and restoration of reinforced concrete structures are not taken until damage occurs which affects power plant operation. These failures can be avoided by predictive civil engineering maintenance and repair. The consequent application and implementation of a life-time management system for power plant buildings is being suggested.
Maintenance of Power Plants by External Personnel Theory and Practice
Ulrich Wolff und Frank Rodemerk
In the liberalised market the potential in cost reduction by outsourcing of maintenance work is increasingly used in power stations. As a support to obtain the most effective and cheapest method to employ external companies in power station maintenance a team from the VGB Committee “Maintenance Management” has compiled the instruction sheet “Recommendations for the Outsourcing of Maintenance Services”. These recommendations, written from maintenance people for maintenance people, contain suggestions from a practical and a legal point of view and enlighten the management of external companies in the maintenance of power stations in theory and practice.
MetalSCAN – An Opportunity for the Condition Monitoring of Gears of Wind Power Plants
Stefan Leske
MetalSCAN is a precise and cost-efficient online-monitoring system for all oil-lubricated gears. Information on the current state of the gear box, e.g. of a wind power plant is provided at any time. The system scans inductively and without false alarm even the smallest metallic residues that can be found in lubricating oil. A total plant loss can be safely detected months before it occurs.
Maintenance Concepts for Gears of Wind Power Plants
Carsten Sikora
The main gear box is a major component of a wind power plant and is thus highly responsible for the plant’s availability. Gear boxes are to be checked regularly - not only due to past experience. The paper will make recommendations for maintenance and inspection activities. Besides, particularities at serration and anti-friction bearing are presented and discussed. Finally an overview is given on the functioning and possibilities of Condition Monitoring System (CMS).
Tube Sheet Optimisation of Tube Bundle Heat Exchangers – Structural Analysis under Typical Thermal Loads
Marc Nadler and Willi Nieratschker
The durability of tube bundle heat exchangers, being used for the cooling of exhaust gases, is significantly determined by the design of the tube sheets. A numerical analysis using models, which were verified with field experiments, supplies local part temperatures depending on main design parameters under different operating conditions.
Replacement of Hot Reheat Pipes with Creep Damage Installed in the 600 MW Unit H of the Weisweiler Power Plant
Andreas Alfred Müller, Gereon Lüdenbach and Rüdiger Kuhles
Pre-planning and comparison of variants as well and implementation of the project in the Weisweiler power plant, unit H, showed that longitudinally-welded tubes made of X10CrMoVNb9-1 can be a sensible, technical-economical alternative, however, under certain precondition, to seamless tubes. Success of the project confirmed that the decision was correct. This approach can also be an alternative in other projects replacing HR systems in the hot reheater area.
20 Years FGD Operating in Lignite-fired Power Plants
Gunther Schwarz and Stephan Müller
In the years 1987/88 a total of 37 FGD plants were commissioned at four lignite-fired plant sites in the Rhenish region. At the initial stage of operation partly severe damage occurred at rubber linings and coatings. Thanks to operating experience and accompanying laboratory investigations, materials based on bromobutyl rubber and vinyl ester coatings are now used for corrosion protection systems. The operating experiences in terms of design and material selection have been considered by the concepts for the FGD plants at the BOA 2 and 3 sites.
Aggressiveness of the Condensate at Cooling Towers with Flue Gas Discharge - First Application of Novel Condensate Measurement Station
Lasse Petersen, Ludger Lohaus, Robert Griese and Heinrich Eggers
In Germany cleaned exhaust gases are generally emitted together with the cooling tower plume. On the inner side of the cooling tower condensing water chemically attacks the cooling tower shell. Specially for the quantification of the chemical aggressiveness of the condensate on the building material, a novel measurement station was developed that has been in use at the natural draft cooling tower of the Staudinger power plant.
Investigations on Aluminum-induced Limestone Blinding at Wet FGD Plants Producing Gypsum
Heinz Gutberlet, Gabriele M. Böhm, Siegfried Neuhaus, Markus Dickamp, Manfred Kraus and Christian Moser
In the wet limestone forced-oxidised flue gas desulphurisation (FGD) process, the dissolution of the limestone after injection into the absorber slurry is one of the key process steps. However, soluble aluminum and fluorides present in the absorber slurry can combine to form aluminum-fluoride complexes that can hinder the process of limestone dissolution. This phenomenon, called “limestone blinding”, can lead to severe problems with the operation and control of the FGD plant, and can lead to a reduction of the overall sulphur dioxide removal efficiency. Investigations at various operating FGD plants, as well as additional laboratory analytical testing, were carried out to study the root causes and the mechanism of limestone blinding in order to better define and implement necessary remedial measures.)
The Use of Waste Water as Boiler Feedwater and Zero Discharge in Power Stations
Rolf Nagel, Klaus Ogiermann and Manuel Graulich
In order to conserve the groundwater deposits, power stations in Northern Europe are increasingly using surface water for the production of process and boiler feedwater instead of drinking or well water. Pre-tests aiming at the realisation of using such waters have been carried out in Southern Europe at two sites where combined cycle plants are under construction. It could be shown that such waste water can be treated in a suitable process chain to obtain makeup water whose values are below those of the VGB Guidelines. While the process engineering is highly complex, the plants can be operated at a reasonable operating and maintenance effort.