Instrumentation & Controls

In 1500, Leonardo Da Vinci drew sketches of a device that rotated when hot air going up a chimney passed through a set of fan-like blades. Leonardo called his invention a "chimney jack," and although it only turned a roasting skewer, it gave birth to the idea of mounting blades on a shaft to convert […]

Remember the slogan, "Never trust anyone over thirty?" Chances are you’ve joined the ranks of the over-thirty generation and are dealing with your own personal "maintenance" issues—not unlike the fleet of generators at larger U.S. power plants, whose average age is about 30. Given the continuing growth in U.S. electricity demand and the cost and […]

Age is wreaking havoc on the U.S. generation industry, especially the coal-fired sector. Industry conferences are replete with hand-wringing over the "brain drain," the lack of skilled personnel, the meager number of students pursuing engineering degrees, and the accelerated retirement of the older workers who make up the industry’s experience base. On top of this, […]

U.S. power producers and owners of industrial steam systems each spend about $15.4 billion annually to combat corrosion in their plants. Scale and deposits are thought to be responsible for another $20 billion a year in reduced plant efficiency and lost generation capacity. Corrosion is the primary cause of every other forced outage, and the […]

Rotary regenerative air heaters capture and recycle about 60% of the heat energy exiting the boiler—energy that would otherwise go up the stack. For a 500-MW coal-fired plant, the recycled energy amounts to about 1.5 billion Btu per hour, and reusing it reduces fuel consumption by about 1,500 tons per day. Although most performance engineers […]

Focus on O&M

The EUCG surveyed 72 separate installations of selective catalytic reduction (SCR) systems at coal-fired units totaling 41 GW of capacity to identify the systems’ major cost drivers. The results, summarized in this article, provide excellent first-order estimates and guidance for utilities considering installing the downstream emissions-control technology.

Sliding-pressure, supercritical plants are all the rage. They generally include certain design features developed for markets and operating environments outside the U.S., where new coal-fired plants have been built in recent decades. U.S. market conditions are different, and considerable capital cost savings—with negligible operating cost differences—are possible if technology options are considered for the next wave of supercritical and ultra-supercritical steam plants.

Compared to most pieces of a power plant, refractory costs very little to install. Yet, if improperly manufactured, specified, stored, mixed, installed, cured, or dried, refractory may cause problems that can significantly decrease a plant’s operating efficiency and flexibility. Like Rodney Dangerfield, refractory design and installation deserve more respect.

Now that many U.S. selective catalytic reduction (SCR) systems are in their fifth or sixth year of operation, a number of utilities are shifting their attention from implementing the technology to operating and maintaining it. Catalyst management and performance are key to the successful operation of any SCR system.