               
|
Emerson's Advanced Gas Analyser Technology Provides On-line Analysis of Hydrogen Cooled Generators
New Rosemount® Analytical on-line gas analyser reduces operational costs, increases efficiencies and enhances plant safety
 |
SOLON, OH (May 22, 2006) – Emerson Process Management has introduced a special
configuration of the Rosemount® Analytical CAT 100 continuous gas analyser
transmitter to meet all of the measurement requirements for hydrogen cooled turbine
generators in electrical power plants.
The on-line thermal conductivity TCD analyser is typically set up with three
measuring ranges. The first and primary range (80-100% H2) is to monitor the
hydrogen purity during normal operation, the second (0-100% H2) and third
(0-100% CO2) measuring ranges allow safe opening of the turbines for maintenance.
On-line gas analysis is used to maintain a high concentration of hydrogen coolant to
ensure cooling efficiency and maintain safe conditions. During normal operation, the
hydrogen purity is monitored in an 80 to 100% H2 range (with air as background gas)
to expose air leaks or hydrogen supply problems.
Keeping the hydrogen as pure as possible is critical for the efficient operation of
a turbine. Every 2% reduction in the purity of the hydrogen coolant increases windage
losses in the turbine and the cost of running an 800-megawatt generator is increased by
up to $1,000 a day. Contaminants in the hydrogen can also be very dangerous and air is
the most common impurity due to leaks.
When the oxygen in the air is mixed with hydrogen, this can create an explosive condition.
However, hydrogen does not support combustion in a nearly pure state (>90%) with the
balance of air. By using the Rosemount Analytical CAT 100 continuous gas analyser transmitter
to constantly monitor the hydrogen purity; any potentially hazardous condition can be avoided,
enhancing safety and maximising efficiency and profitability.
When the turbine needs to be opened for maintenance, the hydrogen is first replaced with inert
CO2 and this process is tracked with the second measuring range in the analyser, 0-100% H2
(with CO2 as background gas). Once all of the hydrogen is removed, air is injected to displace
the CO2 and this is tracked with the third measuring range 0-100% CO2 (with air as background gas).
When all of the CO2 has been replaced with breathing air, it is safe to open the turbine. To restart
the turbine, this process is reversed.
By accurately determining when each purge cycle is complete, the Rosemount Analytical CAT 100
continuous gas analyser transmitter minimises down time. Plant safety is enhanced by ensuring that
the right conditions exist before personnel can open the turbine for maintenance.
|
About Rosemount Analytical
Rosemount Analytical (www.RAIhome.com) is a division of Emerson Process Management. The Gas Division in Solon,
Ohio, designs and manufactures analyzers and systems for Combustion Analysis and Control, Continuous Emissions Monitoring Systems (CEMS),
In-situ Oxygen and Combustibles Analyzers, Carbon Monoxide Analyzers, Opacity Monitors, and a full array of Single and
Multi-component Process Gas Analyzers.
About Emerson Process Management
Emerson Process Management (www.emersonprocess.com), an Emerson business, is the
leader in helping businesses automate their production, processing and distribution components in the chemical,
oil and gas, pulp and paper, food and beverage, and pharmaceutical industries, as well as others. The company
combines superior products and technology with industry-specific engineering, consulting, project management and
maintenance services. Its brands include: Rosemount Analytical, Fisher-Rosemount, Performance Solutions, AMS,
Bettis, DeltaV™, El-O-Matic, Intellution, Micro Motion, PlantWeb™, and Westinghouse Process Control.
About Emerson
St. Louis-based Emerson (www.emerson.com) is a global leader in bringing
technology and engineering together to provide innovative solutions to customers in process control; electronics and telecommunications;
industrial automation, heating, ventilating and air conditioning, and appliance and tools. Sales in fiscal 2006 were $24 billion.
|
|
