POWER May 2011 - 95

EuropE spEcial advErtising sEction
Urea-based SCR side-steps the need for ammonia
Fuel Tech's NOXOUT ULTRA system controls NOx in the flue gas from a 28 MW gas
turbine. By using urea as a raw material, it eliminates the need for toxic ammonia
S
elective catalytic reduction (SCR) can
meet the most stringent limits for NOx
reduction, but the ammonia traditionally
used as the reducing agent obliges operators
of SCR systems to manage the costs and
risks of transporting and handling this potentially
hazardous material.
The NOXOUT ULTRA system from Fuel
Tech is an alternative SCR technology that
uses a stable, safe material - urea - to produce
ammonia at the point of use.
The application shown in the diagram
is for a GE LM2500 gas turbine with a topsupported
heat recovery steam generator
(HSRG) with horizontal gas flow.
Urea solution at 45% is supplied by
tanker or made on-site by dissolving solid
urea granules in water. A dosing skid injects
the urea solution into a decomposition chamber,
at a flowrate controlled as a function of
boiler load and stack NOx concentration.
The decomposition chamber is a directfired
heater burning natural gas or liquid
fuel, with or without preheated air or hot
flue gas. A two-phase compressed-air nozzle
injects urea into the hot gas stream at a
The NOXOUT ULTRA process relies on thermal decomposition to generate ammonia from urea
temperature of 500-550°C. Here the urea
decomposes to produce ammonia, which
exits the chamber diluted in the hot air at a
temperature of 300-330°C.
Installed within the HRSG, whose crosssection
is 3 x 11 m, are an ammonia injection
grid (AIG) composed of five double modules,
Hydrogen drives the future
Metal diaphragm compressors from sera deliver the high
pressures needed for a mobile hydrogen filling station
filling station that will supply hydrogen to
forklift trucks powered by fuel cells.
All the components of the filling station
Pump it up: compressor delivers 350 bar
F
luid metering and compression specialist
sera is using its expertise in high-pressure
diaphragm compressors to further the use of
hydrogen as an energy carrier. Many experts
believe that hydrogen will play an important
role in the carbon-constrained world of the
future, and for several years sera has been
taking advantage of its close market links to
develop hydrogen technology.
One example is a project by sera and
several other companies to create a mobile
S4
are installed in a single container. The high
pressures required to store useful amounts
of hydrogen necessitate two-stage compression:
hydrogen supplied in cylinder bundles
is compressed by a sera diaphragm compressor
to the pressure required for the hydrogen
filling station reservoir. The operating pressure,
currently 350 bar, depends on the vehicle
specification and the compressor design.
The plant is monitored by a programmable
controller which guarantees the safety
of the automatic filling process. The functionality
and safety of the complete mobile
hydrogen filling station has been tested and
confirmed by the German technical certification
agency TÜV Nord.
sera metal diaphragm compressors
supply hydrogen and other gases at high
pressures and free from oil and particulate
contamination. Combined with their ease of
integration into plant safety systems, this
ensures them a promising future in the new
hydrogen economy.
www.powermag.com
and a vertical honeycomb-type catalyst
bed made up of 18 pre-assembled carbon
steel modules. With a distance of just 2.5 m
between the AIG and the catalyst, good
ammonia distribution depends on careful
design and accurate CFD modeling of the
gas flow, Fuel Tech notes.
Swiss hydro plant boost
F
www.ftek.com
orces Motrices Hongrin-Léman SA
(FMHL) in April launched construction
of a new underground facility to double
power capacity of its 240-MW pumped
storage hydropower plant in Veytaux,
Switzerland. The CHF 330 million project,
expected to be completed by the end of
2014, will feature two new pump-turbine
groups to bring the plant's total capacity
to 480 MW. About 420 MW of this power
will be used for operations and 60 MW
will be held in reserve.
The 1970-completed Veytaux plant
uses water discharged from the Hongrin
dam 870 meters above it to generate
power during periods of high demand.
When demand is low, water is discharged
at a rate of 24 cubic meters per second
and pumped up from Lake Geneva to
the Hongrin reservoir for storage. Plant
officials said the new power plant would
meet surging demand for storage capacity,
mainly due to the growth of renewables
in Europe and Switzerland.
FMHL is a company whose majority
shareholders include Romande Energie
(41.13%), Alpiq (39.31%), Groupe
E (13.13%), and the municipality of
Lausanne (6.43%).
www.sera-web.com
POWER | May 2011
http://www.ftek.com http://www.sera-web.com http://www.powermag.com
POWER May 2011

Table of Contents for the Digital Edition of POWER May 2011
