POWER [February, 1 2011]

Cover Stories

The Great Solar Storm of 2012?

The 2009 blockbuster movie 2012 about a global cataclysm combined Hollywood special effects with supposed predictions by Nostradamus; a Mayan calendar that ends on December 21, 2012; and a very rare planetary alignment that supposedly occurs on the same day. Hollywood producers seldom let technical accuracy get in the way of a good story, but suppose, this one time, the story has an element of truth.


Features

Automated Exhaust Temperature Control for Simple-Cycle Power Plants

A common concern for gas turbine power plants is treating exhaust gases to comply with laws restricting pollutants present in the gases that are emitted into the ambient atmosphere. The challenge for designers is to control the exhaust gas operating temperature within a range that maximizes performance of the oxidation and reduction catalysts.


Concerns About Temperature-Equalizing Columns Used for Steam Drum Level Measurement

In the 1950s, temperature-equalizing columns were commonly used in steam drum differential pressure–based devices for measuring water level. However, these columns are problematic because a portion of the reference leg can flash to steam on a pressure decrease (load increase), and this will result in a temporary, false, high-level measurement, which adds to the swell effect. The columns can also result in measurement inaccuracies. It’s time to replace these antiquated instruments with a more modern reference leg.


Designing Fuel Systems for Large Biomass Plants

Compared with other solid fuel–fired plants, the systems and components required for handling and processing biomass appear quite familiar, but important fuel differences must be considered. A successful biomass plant design must provide flexibility for handling the expected wide range of biomass fuel properties and characteristics.


I&C Update on Plant Vogtle Units 3 and 4

Development of Vogtle Electric Generating Station Units 3 and 4—the first new nuclear power plant units in the U.S. in decades—has generated considerable excitement. The next generation of nuclear plants, represented by these units, includes at least two major improvements: the use of passive safety systems and a reliance on digital control systems. The latter represents a gigantic leap in modernization and a fundamental change in control of the plant.


Increasing Generation Ramp Rate at Morgantown Generating Station’s Coal-Fired Units

At Morgantown Generating Station, plant personnel used innovative methods to combine model predictive control with distributed control system–based process control algorithms to improve waterwall temperature control and main steam temperature control and to enhance unit ramp rate capability. The previous heat rate and NOx optimization performance gains were retained. Focusing beyond basic loops of feedwater, air, and O2, the project considered issues such as PID controller override configuration and limitations. The techniques used to overcome these challenges improved unit ramp rate capability beyond any previous unit performance.


New Tools for Diagnosing and Troubleshooting Power Plant Equipment Faults

The Electric Power Research Institute has developed a pair of diagnostic tools that combine and integrate features from multiple sources of plant information. The Diagnostic Advisor and the Asset Fault Signature Database will improve diagnostics for and troubleshooting of equipment faults by providing a holistic view of the condition of plant equipment.


Thermocouple Response Time Study for Steam Temperature Control

One important factor in power plant control system performance is the response time of the process measurement used in the control system. The response time of boiler steam temperature sensors and thermowells is examined, as is those sensors’ and thermowells’ effect on desuperheater temperature response time and, therefore, steam temperature control performance.


Departments

Commentary

Pre-Combustion Technologies: A Key Environmental Compliance Tool

Arizona Public Service’s (APS) plan to close three older coal-fueled units at the Four Corners Power Plant in New Mexico and buy out Southern California Edison’s 48% share of the two remaining units is a creative means of surviving the U.S. Environmental Protection Agency’s (EPA) committed action against coal-fueled generation.

New Products

500-kV Proximity Voltage Detector

HD Electric Co.’s new PRX-500 Proximity Voltage Detector is an addition to its voltage detector product line. With nine selectable voltage ranges from 120 V to 500 kV, the PRX…

Continuous Ultrasonic Level Transmitter

KROHNE Inc. has added the OPTISOUND VU3X Series continuous ultrasonic level transmitter to its extensive measurement product line to meet the specific level or open channel flow measurement needs of…

Extended Generator Drive Ratings for Diesel Engine

John Deere Power Systems (JDPS) introduced extended generator drive emergency stationary power ratings for its PowerTech E 6.8L diesel engine—the first John Deere engine to carry both U.S. Environmental Protection…

Self-Propelled Trailers for In-Plant Use

Wheelift Systems introduced its self-propelled trailers (SPT) in capacities up to 100 tons. They were developed for in-plant operation in congested, confined areas and in narrow intersecting aisles. Highly maneuverable,…

Synthesizing Radial and Axial Ventilation

Rittal’s newly developed TopTherm fan-and-filter units use diagonal technology—an intelligent synthesis of radial and axial ventilation. When installed, it ensures far better air throughput for improved ventilation in enclosures and…

Thermodynamic Steam Trap

Spirax Sarco launched the TD120M Thermo-dynamic Steam Trap, a product engineered for pressure ratings of up to 3,190 psig that is ideal for draining saturated and superheated steam mains. The…

Legal & Regulatory

What Legal & Regulatory Issues Are at the Top of Your Mind?

All of our legal column writers have this issue off (they’ll be back in the March issue), so we are using this opportunity to invite readers to share their legal and regulatory (L&R) concerns.

Focus on O&M

Deferred Maintenance Increases Pump Failures

If your facility has recently seen an upsurge in bearing failures on boiler feedwater (BFW) pumps, you are not the only plant experiencing these unnecessary and costly failures. The failure causes are often elusive, which is why plants have so many unresolved repeat failures.

Designing Large Package Boilers

Designing large package boilers rated at over 400,000 lb/h steam production is a challenge because of shipping limitations within the U.S. and Canada.

Global Monitor

DOI Approves Nine Solar Projects on Federal Land—So Far

U.S. Interior Secretary Ken Salazar in late December approved—for the ninth time since October 2010—a solar power project to be built on federal lands.

Laos Inaugurates Major Revenue-Generating Hydropower Plant

Lao People’s Democratic Republic (PDR), the tiny landlocked country in Southeast Asia of just 6.3 million people, in December inaugurated the 1,070-MW Nam Theun 2 Power Station, a hydropower project in Khammouane Province.

Major Milestones for the AP1000 Reactor

Westinghouse’s AP1000 reactor design hit several milestones in recent months, prompting speculation that it could take the coveted lead in the charge to deploy the world’s third-generation nuclear power plants.

Marine Power Developments Move Forward in North America

In early January, Verdant Power—a decade-old company based in New York—made headlines for filing an application with the Federal Energy Regulatory Commission (FERC) for a project that could allow it to install up to 30 new tidal power turbines in the East Channel of the East River in New York City.

POWER Digest (Feb. 2011)

MHI to Continue Pre-Construction Work for North Anna Unit. Mitsubishi Heavy Industries Ltd. (MHI), through Mitsubishi Nuclear Energy Systems Inc., and Dominion subsidiary Virginia Electric and Power Co. on Dec.…

Readers Write

In the September and October 2010 issues, POWER Contributing Editor David Daniels explored the causes and damage mechanisms of condenser tube leaks (“Taming Condenser Tube Leaks,” Part I and Part II). Dennis J. Schumerth, Valtimet’s director of business development, took issue with several of Daniels’ statements regarding the proper use of titanium condenser tubes. We have given Schumerth the opportunity to express his concerns and for Daniels to reply.

Ukraine Opens Chernobyl to Visitors

The Ukraine will on April 26 mark 25 years after explosions at the Chernobyl Nuclear Power Plant (then in the Ukrainian Soviet Socialist Republic) resulted in a fire that sent a plume of radioactive fallout into the atmosphere and over an extensive area.

Speaking of Power

Reaching Retirement

A recent Washington Post article attacks coal as a fuel with a dim future. The author points to the large number of plant retirements as evidence of its impending demise. Checking the actual data reveals a much different story.

GBR Reports