GE has been awarded a contract by Enel to complete phase six of an eight-phase project at Enel’s coal fired Maritza East 3 (EME3) in Bulgaria.

During this phase, GE will convert two electrostatic precipitators (ESP) from tumbling hammer to GE’s advanced top rap technology, helping to increase reliability of the unit, lower maintenance costs and achieve lower emissions. GE commenced work on the four units at this power station in 2003, in a phased approach, during the now completed rehabilitation project of the power plant.

GE was awarded the top rap conversion of fields 3 and 4 of all ESPs for the four boilers in 2005. Execution of the project was staged to one boiler per year with final completion in 2008. The performance of the partially rebuilt precipitators was demonstrated to be successful, and in order to achieve an additional margin on the emission limits, EME3 decided to also rebuild fields 1 and 2 of the ESP.

ESPs collect airborne particulates using electrical current to deposit the particles on large steel surfaces inside the ESP. To maintain the collection efficiency of the system, the collector plates and high voltage discharge electrodes need to be regularly cleaned of dust by a rapping system. Cleaning on the original units at Maritza used rotating hammers mounted inside the ESP. The hammer train components are exposed to the flue gas and suffer wear in the hostile environment. Having the rotating hammer train inside the precipitator precludes maintenance while the precipitator is on line, resulting in unplanned outages to repair the hammer trains.

GE’s top-rap design mounts the rapping devices externally on the roof of the precipitator, allowing maintenance to the rappers while the precipitator is online.

Since GE’s top-rap technology does not make use of a mechanical hammer train, but rather uses a reliable electrically actuated rapper, maintenance is virtually eliminated.





Thermocouples offer longer life in harsh process environments


A new thermocouple offers high performance and longer life in harsh process environments, providing superior resistance to temperature, vibration, impact, corrosion and abrasion.

The Aeropak Great from Japan’s Okazaki Manufacturing Company (OMC) is a thick wall mineral insulated (MI) thermocouple cable, which is ideally suited to harsh, high temperature process environments such as incinerators, heat treatment furnaces and industrial ovens, as well as for measuring the temperature of molten metal.

Aeropak Great can also be supplied with a hard coating such as cement or Stellite, which offer superior resistance in other harsh high temperature applications, including heavy oil, pulverized coal-firing furnaces, cement kilns and dispersion kneaders used in the mixing of plastics or rubber.

With Aeropak Great, the gap between the element and the thick wall sheath is densely filled with high purity magnesium oxide (MgO), which prevents any residual air from penetrating the sheath. This enables faster response times compared to conventional standard thermocouples.

Aeropak Great offers long life even under harsh operating conditions, and is available in long cable lengths of up to ten metres. It is supplied in large diameters with a very thick wall sheath (up to 22mm outside diameter), providing a high resistance to vibration and impact shocks. Aeropak Great performs very well in bright annealing furnaces and carburization ovens, where Ta (tantalum) wires are added to Hoskins 2300 material, the selective oxidation rate of Type K thermocouple wire when exposed to H2 gas can be reduced significantly.





Alstom wins €90m power plant control system order in South Africa


Alstom has won a contract worth €90m ($121m) for the automation of Eskom’s latest coal power plant project, Kusile.

Alstom Power will engineer, supply and install its latest ALSPA Series 6 distributed control system (DCS). The contract follows a similar order for Kusile’s sister plant, Medupi and forms part of Eskom’s multi-billion rand expansion programme to double South Africa’s electricity capacity in the coming decades.

This programme covers the building of new capacity and optimizing existing fleets, such as retrofitting nuclear and coal plants such as Koeberg and Arnot. Alstom’s flexible control system will help Eskom maximize its fleet’s efficiency and stabilize the system by enabling real-time information exchange between baseload and renewable power plants.

“Eskom is rising to the challenge of meeting South Africa’s growing power needs as the country continues to industrialise while simultaneously meeting the energy security challenges of the 21st century. Our integrated power control solutions will allow them to manage their assets more efficiently and with added flexibility,” said Laurent Demortier, Senior Vice President of Alstom Power’s Energy Management Business.

The ALSPA Series 6 DCS is designed to ensure consistent and safe control for all parts of a power plant. The system includes the critical controls for turbines, generators and balance of plant (BoP) components. It also provides an advanced control and optimization application module. Alstom has had a presence in South Africa for 100 years and its turbines comprise 80 per cent of installed capacity.





Greenbank Group to supply Chinese power plant with G-CAM carbon-in-ash monitor


The UK’s Greenbank Group has won a contract with Datang Guiguan Heshan Power Generation, one of the largest power generation companies in China.

The contract marks a significant milestone for Greenbank in the coal fired power market, demonstrating Greenbank’s global strength and commitment to delivering market-leading clean coal technology products. Under the contract, Greenbank will supply China Datang with its G-CAM carbon-in-ash monitor for the Heshan power station, the largest coal fired power station in the Guangxi Province of China.

Greenbank’s G-CAM carbon-in-ash monitor is an online analyzer which uses cutting edge microwave techniques to measure the amount of unburnt coal remaining during the power generation process. The ability to do this will provide Heshan Power station with real time information about the combustion efficiency and performance of their coal fired boilers and enable them to measure, improve and optimize their combustion and emission levels

“This is a significant contract for us as it further reinforces our position as a one of the leading global suppliers of coal-fired boiler optimization products”, said Charles Conroy, Managing Director of the Greenbank Group. “Technology that improves boiler efficiency plays a crucial part in making coal a significantly cleaner source of fuel. We strongly believe that by continuing to invest in research and development in products such as the G-CAM we can help coal-fired power stations like Heshan become greener, cleaner, and more efficient”, he added.

Greenbank’s G-CAM analyzers will be installed and commissioned on two of the Heshan power station’s coal fired boilers early next year.





Foster Wheeler awarded CFB boiler contract for CO2 capture development plant in Spain


Foster Wheeler has been awarded a contract by Fundación Ciudad de la Energía (CIUDEN), an institution created by the Spanish Government, for the design and supply of a circulating fluidized-bed (CFB) unit for testing Foster Wheeler’s Flexi-Burn carbon capturing CFB technology.

This unit will be part of CIUDEN’s Integrated Carbon Capture and Sequestration (CCS) Technology Development Plant (TDP) located near Endesa’s Compostilla power plant in Ponferrada, Spain.

Foster Wheeler has received a full notice to proceed on this contract. The terms of the agreement were not disclosed, and the contract value will be included in the company’s first quarter 2010 bookings. The unit is expected to be operational by the second half of 2011 with testing programs expected to follow shortly thereafter.

Foster Wheeler will design and supply the 30 MW Flexi-Burn CFB test unit and someauxiliary equipment and provide site advisory services for the project.

Flexi-Burn is Foster Wheeler’s version of carbon capture technology based on oxygen combustion (oxyfuel) for coal plants. Unlike, pre-combustion (IGCC plant) or post-combustion technologies (amine CO2 scrubber placed behind conventional coal boilers), oxygen combustion technologies allow the boiler to produce a CO2 rich flue gas, thus reducing the need for expensive and energy-intensive CO2 gas separation equipment.

The CIUDEN unit will be designed to test burn a wide range of domestic (anthracite) and imported coals, as well as biomass. One of the objectives of the incorporation of this unit into the TDP is to validate Foster Wheeler’s Flexi-Burn CFB technology at the required scale before proceeding to a possible full-scale demonstration plant.

“Foster Wheeler has been developing Flexi-Burn CFB technology for over four years and, in collaboration with CIUDEN’s Technological Development Plant, we are one step closer to bringing this promising technology to market,” said Eric Svendsen, chief executive officer of Foster Wheeler Energia, S.L. in Madrid.

The CIUDEN board said it “has full confidence with Foster Wheeler’s ability to deliver the best quality CFB boiler. Foster Wheeler has demonstrated its state-of-the-art CFB boiler technology as a world leader, proven in large-scale applications, providing fuel flexibility and environmental compliance and we are pleased to have selected them for the CIUDEN TDP project.”

Fundación de la Energía (CIUDEN) is an institution created by the Spanish Government in 2006 to put into practice strategic objectives on CCS. Its main objectives are R&D of efficient, cost effective and reliable technologies through the design, operation and construction of a large-scale integrated plant for CCS.





Energetix’s new CHP boiler


Energetix Group plc, a group of companies with three cost-effective products – Genlec, Pnu Power, and VPhase – to meet the growing demand for alternative and efficient energy, is pleased to announce that its subsidiary Energetix Genlec Limited has developed an integrated micro-CHP boiler appliance for the UK domestic market, under the trade name ‘Kingston’.

Kingston is designed to generate 1 kW of power which can be utilized in the home, and any excess not used can be exported to the national electricity grid. It is anticipated that the Kingston Organic Rankine Cycle (ORC) based appliance will have a significantly shorter payback period compared to other micro-CHP technologies.

The unit is compact, wall-hung, light-weight, and tailored for installation in UK homes. It integrates the Genlec ORC micro-CHP technology, which generates electricity using heat produced by a gas boiler. The target performance for the Kingston appliance is to have an overall efficiency equivalent to a high-efficiency condensing boiler and an electrical efficiency of ten per cent.

Genlec has taken advantage of the improving conditions for micro-CHP in the UK market, particularly with the introduction of feed-in tariffs. The Kingston is undergoing laboratory tests to determine its heating and electrical performance, and is expected to have full UK certification, including CE compliance during 2010.

Potential manufacturing and marketing partners have shown significant interest in the appliance.

Adrian Hutchings, CEO of Energetix Group, said: “We are currently in discussions with a major white goods appliance manufacturer and with power utilities for both its production and sale in the UK. We view feed-in tariffs as useful in helping to drive the uptake of our micro-CHP products; however, unlike other micro-CHP technologies, the Kingston is inherently low-cost and, as such, the economic case for it is not reliant on subsidies.”





Drax Power and Siemens Energy preserve vital piece of power engineering history ahead of modernization project


A colossal steam turbine has made its penultimate journey from Drax power station near the English town of Selby, North Yorkshire, where it has been generating electricity for Britain’s households for the past 36 years, to where it awaits its final resting place.

The engineering marvel has finished its working life at the power station and will be replaced with more efficient Siemens turbines as part of a £100m ($152m) steam turbine modernization project. The unique collaboration between Siemens Energy, Drax and Tyne & Wear Archives and Museums to showcase the first steam turbine of this size to the public anywhere in the world has been years in the making.

Weighing in at 25 tonnes, the steam turbine is part of the UK’s historic first 660 MW steam turbine generating sets – the largest in the UK. Its return to Tyneside, where it was designed and made in 1967, marks the first stage of a collaboration which will celebrate the achievements of Tyneside’s continuing engineering prowess at Newcastle’s Discovery Museum.

Until space in the museum is ready the turbine will be kept at the Regional Museums Store at Beamish, where it will be on view to visitors from the middle of this year.

Dating back to 1967, the 660 MW Parsons turbines are the most powerful high speed (3000 rpm) turbine-generators which Parsons designed and built in the UK before Siemens acquired the business in 1997. Drax was the first power station to commission 660 MW sets in the UK.

In the mid-1960s, the Central Electricity Generating Board decided to build a new power station at Drax in Yorkshire with a unit size of 660 MW, the largest turbine size specified in the UK. The station was intended to contain six machines to give an overall rating of 4000 MW, which would make it the largest coal fired power station in Europe and capable of providing around 10 per cent of the UK’s power requirements from a single site.

Three units were ordered initially then a further three machines were ordered in the mid-1970s. This was the culmination of a programme of rapid growth in the size of turbine generators to meet the UK’s power needs. Between 1950 and 1965 approximately, turbine sizes had grown from 60 MW to the size proposed for Drax of 660 MW. The plan was successful and Drax has met its targets achieving various efficiency and output records over the many years the station has been in service.

The turbine generators for Drax were designed and manufactured by CA Parsons which is now part of Siemens Energy. Just prior to the Drax contract, in 1965, Parsons took over the turbine generator business of GEC. This meant that the engineering knowledge of two major manufacturers was combined.

Drax was the first contract to be awarded after the takeover and so could benefit from the experience of both companies and use the best available features of the day. The decisions seem to have been justified as the station has been able to meet the original design life and more.

Drax was the first station to have a design life of 200 000 running hours plus 5000 starts with fast starting and load cycling capability (previous machines were simply required to complete around 15 years service which was interpreted as 100 000 running hours). The first units have met this target having completed over 220 000 hours on the lead machines.


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