Stork Thermeq has a 24/7 servicestaff specialised in commissioning, maintenance and repair of burner systems, pressure parts or deaerators. These services are available for all kinds (brands) of power equipment. In Dutch language: ketel onderhoud, ketel storing, brander storing.

Stork has a customer oriented approach based on turn-key solutions. Most projects start with a basic study for investigating specifications for the RFQ. After ordering the following activities are planned: front-end engineering, project engineering, manufacturing, erection on-site + commissioning, monitoring (of emission levels) + service. Individual projects for engineering studies and manufacturing are often the start of a long term relationship.

Ultra Low NOx burners, Low NOx burners, Low NOx-techniques (OFA, FGR, reburning), multi-fuel applications, LNG retrofits, deaerators and pressure parts for boiler systems.

Revamp is synonym for retrofit, especially for boiler systems, burners and BMS (Burner Management Systems).

Recently Stork participated in a project for firing palm tree oil and wood chips. Stork has manufactured a tailor made boiler system for this sustainable energy system.

The process control and instrumentation group consists of skilled and experienced personnel who are specialized in measurement, instrumentation, control, safe guarding and automation for a variety of burner and energy systems.

Most projects are based on the Stork competence in mechanical design and processing. From project management, front-end engineering, project engineering, manufacturing, delivery, erection, start up and training Stork Thermeq can do the job.

In a combined cycle power plant (= CCPP) or combined cycle gas turbine (= CCGT) plant, a gas turbine generator generates electricity and the waste heat is used to make steam to generate additional electricity via a steam turbine; this last step enhances the efficiency of electricity generation. In German language GuD - Gas- und Dampfanlage.

A HRSG ( = heat recovery steam generator) is a heat exchanger that recovers heat from a hot exhaust gasses of a gas turbine. It produces steam that can be used in process or to drive a steam turbine. A common application for a HRSG is in a combined cycle power station RSG. This combination produces electricity more efficiently than either the gas turbine or steam turbine alone. The HRSG is also an important component in cogeneration plants. In other languages: Abhitzekessel, afgassenketel.

This boiler – equivalent to a HRSG - is used in waste incineration plants.

A power plant for electricity production as well as co-generation of steam for processing

European Refinery Association for Environment, Health and Safety.

The European IPPC bureau.

Flue Gas Desulphurisation.

Flue Gas Recirculation.

Over Fire Air.

Low Nox Burner.

Reburning.

Selective Catalytic Reduction.

Different techniques - mechanical as well as chemical - to decrease the NOx-emission level. It is often practiced in processing (industry and utilities) and transport. NOx = NO and NO2 collectively.

Most common is mg/Nm3 volume based on dry flue gas corrected to 3% O2 for gas and oil firing and corrected to 6% O2 for coal firing. For HRSG-units mostly g/GJ (mg/MJ) are used.

Stork Thermeq has different mechanical solutions for lowering NOx-values. These techniques are tailor made and depends on boiler characteristics, parameters and NOx ELV’s (Emission Limit Values). In other languages: NOx reductie, NOx Reduzierung, Reduccion de NOx.

The revised Large Combustion Plant Directive (LCPD 2001/80/EC) aims to reduce acidification, ground level ozone and particles throughout Europe by controlling emissions of sulphur dioxide (SO2), oxides of nitrogen (NOx) and dust (particulate matter (PM) from large combustion plants. The revised LCPD supersedes Council Directive 88/609/EEC, and contributes to achieving the targets of the Convention on Long-Range Transport of Air Pollution (CLRTAP), the Multi-pollutant & Multi-effects protocol and the National Emission Ceilings Directive (NECD). The revised LCPD, applies to combustion plants above 50MW thermal (MWth) running on solid, liquid and gaseous fuels and takes into account advances in combustion and abatement technologies. The LCPD introduces stringent emission limit values (ELV) for all Large Combustion Plants (LCP).
For existing plants (pre-1987), the LCPD gives EU-Member States the option of either applying the new Emission Limit Values (ELVs) or developing a National Plan to reduce emissions. A National Plan must reduce the total annual emissions of NOx, SO2 and particulates from existing plants to the levels that would be achieved by applying the ELVs to the existing plants in operation during 2000, by the year 2008. By 1 January 2008 EU-Member States shall comply with the Revised LCPD either by ensuring that existing plants comply with the ELVs or that existing plants are subject to a National Plan, except for existing plants that are exempt under the limited operating life derogation.

The NEC 2001/81/EC is a complementary piece of legislation, which introduces legally binding limits on national emissions of NOx, SO2, ammonia and volatile organic compounds from 2010. The methods by which the emissions reductions are to be achieved are not prescribed but Member States must submit their national plans for emissions reductions to the European Commission.

BAT (= Best Available Technology) is a term applied with regulations on limiting pollutant discharges with regard to the abatement strategy. Similar terms are best available techniques, best practicable means or best practicable environmental option. The term constitutes a moving targets on practices, since developing societal values and advancing techniques may change what is currently regarded as "reasonably achievable", "best practicable" and "best available".
A BREF (= BAT Reference) is a document based on the BAT (= Best Available Technology – in Dutch language BBT – Best Beschikbare Techniek) for prevention and reduction of pollution. There are vertical BREF’s per sector, for instance the “Best Available Techniques for Mineral Oil and Gas Refineries”. Horizontal BREF’s are based on activities as water- or waste treatment. The BREF’s are developed by the EIPPCB on these different IPPC sectors.

BAT reference documents prepared to deal with topics common to more than one IPPC industrial sector (f.i. storage, cooling, waste water and waste gas and monitoring).

All facilities under the NOx-emission trading system should correspond with the limited values in their license. For investments in new equipment and retrofits the emission targets in these licenses should be based on these BAT (Best Available Techniques) as mentioned in the BREF’s. Installations who don’t participate in the NOx-emission trading system should apply to the general BAT’s.

The EPER (= European Pollution Emission Register) is an on-line database with emissiondata about different pollutants and sources. These data about companies, sectors, regions, etc. are per download available.

IMPEL - The European Union Network for the Implementation and Enforcement of Environmental Law (IMPEL) - is an informal network of the environmental authorities of the Member States, acceding and candidate countries of the European Union and Norway. The network is commonly known as the IMPEL Network. The European Commission is also a member of IMPEL and shares the chairmanship of meetings.

IPPC - Integrated Pollution Prevention & Control - is the EU-Directive 96/61/EG dated 24.09.1996 for integrated prevention and reduction of pollution. In Holland the IPPC is integrated in “Wet Milieubeheer” and “Wet verontreiniging oppervlaktewater”.

Low NOx burners and Ultra Low NOx burners are primary NOx control techniques, Additonal reduction techniques such as, OFA (Over Fire Air), FGR (Flue Gas Recirculation) and reburning are also practiced.

Burning systems in utilities and industrial power plants (LCP’s – Large Combustion Plants) especially developed for reduction of the NOx emissions.

The Impulse burner for gas and oil has been developed to meet the most stringent NOx requirements. The basic principle is the staged injection of the fuel gas. Using these techniques the Impulse achieves maximum NOx reduction without effecting the boiler efficiency. The NOX emission using the Impulse burner complies with the most stringent emission requirements. The Impulse burner is suitable for new installations as well as retrofits.

The IMPULS has been closely monitored in new and retrofit installations, with NOx-values below 50 mg/Nm3 being reported in large combustion plants.

The typical feature of the DRB burner is the staged supply of combustion air. Part of the air is fed to the centre of the burner throat, while the rest of the air is skirting the flame like a peel. The effect of falling flame temperature and oxygen concentration decreases the formation of thermal and fuel NOx. The DRB burner has been practiced for new boiler systems as well as retrofit projects.

The DRB has been practised in many new and retrofit installations with NOx-values below 100 mg/Nm³.

The guaranteed turn down ratio for oil and gas firing is 1:5. This means, the Impulse and DRB can be applied between 20% (= base load) and 100% (= full load).

Industrial burners are used for combustion of fuel and / or waste streams. In general the following burner types are available for industrial purposes: Ultra Low NOx burner, Low NOx burner, throat burner, duct burner and incineration burner.
In other languages: industrie brander, Industriebrenner, Bruleur industriel, Bruleur industrial.

Most retrofits are based on compliance to regulations for NOx-reduction of LCP’s (Large Combustion Plants). With Ultra Low NOx burners ELV (Emission Limit Values) are achieved. Changing fuel systems and the combustion of waste streams (multi fuel) are also a motivation for retrofits and upgrades.
In other languages: retrofit, conversion de chaufage, modificaciones en instalacion existente, optimalisation des rendements, reconstruccion.

Stork has a product-range for direct firing (DRB + Impuls) as well as supplementary firing: throat burner and in-line duct burner. In Dutch language: keelbrander + tulpbrander.

The in-line duct burner and the throat burner are used for supplementary firing.

In several projects burner systems for multifuel have been applied. For example, recently a retrofit of five boilers was established for combustion of eight different fuel types in the same burner.

Stork Thermeq specializes on oil, gas and coal, for instance natural / refinery fuel gas, heavy fuel oil / crude oil, heavy residues pitch , light oil, and different kind of waste streams in the (petro)chemical industry. Coal burners for hard coal. Special burners for waste liquids like animal fat.

Stork Thermeq started in the seventies with retrofits for burner systems. Following the latest development Stork Thermeq has a major market-share in Europe and Asia.

Front-End Engineering (mechanical, chemical, etc.), Project Engineering, Manufacturing, Site erection, Commissioning and After sales Services.

Stork has assembled different brands of flamescanners and flame monitoring equipment.

For R&D purposes Stork has a 10 MWth test facility on the production site. This test rig is also available for customized research.

Stork is combining the deaerating and storage function in one vessel. So no deaerator/ top tank is needed. This means that you have a minimum overall height and, a Stork Spray-type deaerator has a flexible design.

There is no limitation in design. That means that we can design a deaerator in every size that you wishes. We have references for 7.000-8.000 tons/hour.

Only when there is a high chance of erosion the steam charging device shall be made of stainless steel.
The Stork Sprayer is always made of Stainless Steel. All other parts are normally made of Carbon Steel.

Yes, Stork Thermeq can supply a vacuum deaerator.
In case of oil and gas firing on a HRSG for instance, Stork will design one deaerator which can be operated both under vacuum conditions and also under over pressure conditions

Stork does supply deaerators for more than 75 years already.
The first Stork deaerator was supplied to a Dutch Power Plant Arnhem in the Netherlands (Gelderland on 25 October 1933).
In total we have supplied appr. 3.500 deaerators worldwide.

Under normal working conditions there will be no corrosion allowance necessary.
Stork’s design has shown, no corrosion damages to the vessel.

No, the design codes in general prescribes PWHT above a certain wall thickness.
Post Weld Heat Treatment Services ( PWHT ) is defined as one of heat treatments done after welding/machining to improve the mechanical properties of welds and the machined surfaces. In concept, PWHT covers many different potential treatments. However, in steel fabrication, most common procedure used is Stress Relieving.
A well known phenomenon for deaerators is a surface cracking in the deaerators. An adequate method to lower this risk in PWHT.
According to the customer requirements Stork can supply deaerators with PWHT.

The power of the Stork Spray type Deaerator is that it can be simply adjusted to your wishes.
So all deaerators are specifically designed according to customer specifications.
This means that we can make the deaerator tailor-made.

The Stork Spray-type deaerator can handle every capacity, because we deliver a deaerator that is tailor-made. So we adjust the size to your capacity.
For example nuclear applications: we can deliver a capacity up to 7.000 t/h or more.

Superheated steam; Saturated steam; Wet steam; Hot water.

One of the advantages of the Stork Spray-type deaerator is that it has a minimum vent-loss because of the fact that the sprayer acts as an internal vent condenser already. There for an external vent condenser is not necessary
In a Stork Spray type deaerator there is always an optimal match between incoming condensate flow and the steam flow.

Yes, we can reach values of 5 ppb dissolved oxygen in the boiler feed water with the Stork Spray-type deaerator from a 10% - 110% boiler load. And we can reach this level without using an oxygen scavenger.
The input details and heat balances must be known to us to judge the possibility of reaching 5 ppb or lower.

10%-110% boiler load, from vacuum to overpressure.
Sliding pressure operation is also possible.
The deaerator can be controlled by pressure and/or water level.

The average life time of the Stork Spray-type deaerator is more than 30 years.
But there are Stork deaerators in operation that have been operating for over 70 years now.

The Stork Spray-type deaerator is maintenance free; this is one of the main advantages.
For regular inspection according the code only a gasket for the manhole and the sprayer are needed (commissioning spares).
The only spares for two years operation are gaskets for manholes / sprayer and bolts and nuts.

During normal operation, the deaerator pressure (and therefore the outlet temperature) is controlled by a steam supply control valve. The level in the deaerator is controlled by the incoming water control valves.

In our own workshop in Hengelo, the Netherlands. Stork also cooperates with local manufactures in many regions.

Yes, it’s possible to manufacture the Stork deaerator under license by a ISO9001 qualified vessel manufacturer.
The Stork sprayer and the basic engineering will be supplied by Stork.

The capital investment of a turn key SwirlFlash® system depends on the location, the available equipment and above all of the size of the installation. Stork Thermeq is willing to make you a detailed quotation or give you precise information, based on your local situation. Compared to a new gas turbine the capital investment is cheap, but it might appear expensive compared to other inlet air humidification systems. However, it should be considered that the typical annual MWh generation of the SwirlFlash® system is about 3 times more than a conventional fogging system. As a result the return on capital investment is about 1,5-3 years! In countries where NOx has a market price, the ROI is even shorter.

The return on investment depends, of course, on the investment costs and the local revenues per generated MWh. Depending on both conditions the ROI is typically between 1,5 and 3 years. For larger GT’s the ROI is in general shorter then for smaller GT’s. In those countries were based on legislation NOx has a market price due to the introduction of a trading system, the ROI is even shorter.

For the single shaft heavy duty gas turbines an injection water rate of 2% of the mass flow of air will result in approximately 8-12% extra power output, 2% (relative) efficiency increase and 25-40% less NOx emission under ISO conditions. The exact data depend on the ambient conditions and the specific gas turbine. Higher ambient temperatures and lower humidity will give more pronounced effects as low temperatures and high humidity. But under all ambient conditions the effects is highly interesting for a power producer.

Stork Thermeq offers a turn key delivery, comprising of:

• A basic and detailed engineering package
• QA/QC plan
• High pressure pump unit including control equipment
• A heat exchanger including temperature control and control valve
• Injection tube assemblies including a filter unit and required nozzles
• A duplex water filter
• Installation supervision
• Commissioning
• Training
• Performance measurements
• Calculation on boiler and complete system for optimal plant integration

The number of spray nozzles will be determined by after CFD modelling of the GT inlet.
However we use 10 g/s as an average flow per nozzle. This means that for large GT we use up to 1000 nozzles in the GT inlet, while for average size (40 MW) we use approx. 300 nozzles.

The spray nozzles have a screwed connections in the thick walled injection tubes. This connection is tested at >500 Bar.
Next to this a seal weld is applied to secure the nozzle and at the same time provide 100% leak tightness.
Until now not any failure has occurred and Stork Thermeq is convinced that this rigid construction is suitable for this application.

The SwirlFlash® spray system has a much larger operational range than any conventional spray system or inlet air chiller. It can be used at temperatures and relative humidity where other spray systems fail to have effect. This means that the SwirlFlash® technology adds more power to your system during a longer period of time. The result: more MWh's than in any other system!

The lowest combination of humidity and temperature is 5 degrees C and 0% RH. Under these conditions a conventional spray system of 2% water of 15 C would result in sub zero air temperatures and ice formation. Under these conditions the SwirlFlash® system using hot water can still create an 8% power boost.

For the other extreme: high ambient temperature (30 degrees C) and 100% RH the inlet air chillers cannot be used at all since the water cannot evaporate. But the SwirlFlash® system can! Even under these conditions the power is boosted by 10-15% (when 2% water is injected).

SwirlFlash® creates water droplets sizing below 5 μ . Droplets of this size do not cause erosion.
The droplets are so tiny that they are in fact aerosols. The droplets behave like smoke and go around an object. The mass of the droplets is too small to penetrate the layer of stagnant air around an object (even a moving object like a rotating blade). This means that when the droplets approach the rotating blades, they simply move with the air around the blade. Inspection of a specific 30 MWe gas turbine after 300, 1300 and 2700 hrs of operation showed no erosion. A picture of the leading edge of a compressor blade (first row of Amer 8 power station after 2700 hrs of SwirlFlash® operation) is shown below. The compressor was completely clean without dirt, stain, deposits or corrosion products.

Yes, as in every cloud of droplets coalescence occurs.
It is a natural phenomenon that occurs when two or more droplets collide. The driving force is the lower surface energy of a larger droplet compared to the total surface energy of two or more droplets. Droplet coalescence, however, depends on the local conditions. Under evaporative conditions occurring using SwirlFlash® , a layer of water vapour surrounds the droplets and this reduces collision and growth. Under these conditions the individual droplet size reduces rapidly till the droplet has disappeared. When the conditions prevent evaporation and the droplet density favours collision, a limited increase in size has been observed. At the nozzle the average droplet size is 2-3 micron (max. droplet size is 5micron); at a distance of half a meter from the nozzle an incidental droplet size of 7 micron diameter has been observed. The droplet size distribution remains steep, however!

In general gas turbine manufacturers, the OEM's, are highly interested in the SwirlFlash® Technology. Almost all of them are investigating the possibilities to offer inlet air cooling and overspray systems to their customers themselves. This means that SwirlFlash® is a competing system for power augmentation and NOx reduction. The SwirlFlash® Technology however, offers them unexpected features and benefits. Stork Thermeq is discussing application possibilities with a number of OEM's in order to reach agreement with them.

Definitely! Not only the droplet size is a quantum leap forward, but the fact that overspray conditions can be generated under almost all circumstances is essential for the amount of power that can be produced and the utilization time.
Normal evap coolers and foggers evaporate cold water in the inlet air. When the relative humidity is low, this results in lower temperatures. This is interesting for high ambient temperatures but a problem for lower temperatures (<10 C) since ice formation due to cooling can be expected. When the humidity is already high, evap coolers and foggers have no effect since the water cannot be evaporated.

If water droplets smaller than 5 micron can be produced in huge volumes (10-30 m3/h), cold water spray would be a good alternative as far as erosion is concerned. Until now this has never been achieved!

Stork Thermeq SwirlFlash® technology allows injection in cold and hot ambient air under all conditions of relative humidity. In cold and dry ambient air a very limited part of the hot water evaporates (cooling down the air), but the rest of the water heats-up the air and prevents ice formation. The result is humidified air well above the freezing point and a sufficient amount of overspray water to generate extra power in the gas turbine. Under conditions of hot and humid ambient air almost all injected water enters the compressor of the gas turbine. Though the inlet air is not cooled by evaporation. The evaporation of the water in the compressor results in the significant extra power from the gas turbine.

Yes! As boiler specialist Stork Thermeq knows very well what risks are involved when the water quality of an installation is poor. Compressor fouling and blade corrosion can be the results when using poor water quality for inlet cooling hence the reason why we use demin water.
Most power stations have demin installations and consider it quite normal to use this water quality.

Definitely not! The SwirlFlash® system is in no way a replacement for an on-line compressor washing installation. The SwirlFlash® spray system produces water droplets of < 5 micron. These droplets are so small that they tend to move around the blades rather than hitting the blades. A typical washing installation will produce large volume droplets. These droplets behave like canon balls and they are supposed to hit the blades surfaces to ensure that the dirt and stain is removed. The optimum operation of the gas turbine is a mix of SwirlFlash® injection, combined with periodic compressor cleaning.

Stork Thermeq offers SwirlFlash® systems in different configurations. The standard scope of supply is a turn key system and Stork Thermeq offers a process warranty and an operational warranty.

All basic components are pre-fabricated at the manufacturers work shop and transported to the site. An average plant may expect less then 5 days outage to install the basic components, i.e. the injection tubes and plant connections. If the preparatory work has been done, it will take only a couple of hours to install the tubes themselves in the inlet ducts of the gas turbine. If necessary, the injection tubes can be removed and inspected during operation of the turbine.

Yes, the nozzles wearing components. Due to the combination of higher pressure and high temperatures, the nozzle materials are under heavy attack of the demin water. Stork Thermeq has developed two types of nozzles:

1. Short lifetime nozzles for application where SwirlFlash® is used in peak periods only.
2. Longer lifetime, 6000-8000 hrs or 1 year operation for more intensive or continuous operation.

Long lifetime nozzles for 20.000 hrs are under development as part of our R&D program.