Archive: Coal

Designing and maintaining steam coil air preheaters for reliability and effectiveness

If engineered well and drained properly, a simple finned-tube heat exchanger can help maximize a fossil-fueled power plant’s combustion efficiency, capacity, and air pollution reduction. Use the guidelines in this article either to return a disabled steam coil air preheater to service or to improve the performance of a unit that may have been wasting […]

How accurate primary airflow measurements improve plant performance

Primary airflow has a major impact on the efficiency, capacity, and cleanliness of pulverized coal–fired generation. Inaccurate measurements that underestimate primary airflow levels can lead to negative operational outcomes that include increased boiler gas temperatures, flyash loss-on-ignition, excessive NOx emissions, and higher-than-necessary fan power consumption. We remind you how to avoid those headaches.

Curbing the blue plume: SO3 formation and mitigation

Understanding why stack emissions become opaque leads to better choices of systems for controlling SO3 and other pollutants, based on current and future plant operating configurations.

Preparation keyed Entergy’s responses to Katrina, Rita

With the 2006 hurricane season about to begin, climatologists are predicting that the Atlantic Ocean will spawn 17 “named” storms this summer and fall, with 9 categorized as hurricanes and 5 expected to be “intense.” Whether or not your plant lies in a vulnerable coastal area, you’d do well to learn a few lessons from Entergy’s unique experience last year.

Big bucks for carbon sequestration

The California Energy Commission (CEC) recently awarded about $14 million for carbon sequestration projects to be overseen by the West Coast Regional Carbon Sequestration Partnership. Westcarb, as the partnership is known, is part of the U.S. DOE’s effort to deploy technologies through its Regional Carbon Sequestration Partnership (RCSP) program. New members Alberta and British Columbia […]

Why new U.S. supercritical units should consider T/P92 piping

T/P92 is being heralded as a superior and lower-cost alternative to T/P91 for new power plants with pressures above 3,600 psi and temperatures above 1,100F—such as the supercritical and ultra-supercritical units proposed to be built in the U.S. over the next few years. The switch from T/P91 to T/P92 would represent the next step in […]

Stressed merchant industry hopes for better days

The U.S. power generation industry is changing at warp speed, via regulatory changes, consolidation, mergers, and sales of assets at yard-sale prices. New players have entered the market and become major players overnight, while several mainstays have gone bankrupt. Though many of the latter blamed high gas prices for their woes, well-diversified merchants enjoyed a record year. Whatever changes are in store for the business of combined-cycle generation, you can be sure that innovations in plant design and O&M such as those described in this special section will keep pace with them.

Gas turbine "refueling" via IGCC

The jury is still out on the economic and technical feasibility of burning gasified coal to generate electricity. Gasification technology has yet to be proven on a utility scale, especially with Powder River Basin coal as the feedstock. And on the generation side, there are more questions than answers about the capital cost and availability of integrated gasification combined-cycle (IGCC) plants. But with natural gas prices high and rising, it’s definitely worth examining whether it would be economically and technically feasible to convert the existing U.S. fleet of gas-fired combined-cycle plants to burn gasified coal.

Designing wet duct/stack systems for coal-fired plants

A multitude of variables must be accounted for during the design and development of a wet-stack flue gas desulfurization system. The five-phase process detailed below has proven effective on more than 60 wet-stack system design studies. A basic understanding of these concepts will help inform early design decisions and produce a system amenable to wet operation.