O&M

Employees of Alabama Power, a Southern Company subsidiary, routinely work near energized wires, intense heat, nuclear fuel, heavy equipment, moving vehicles, and pressurized equipment, as well as under other conditions that require exceptional safety attitudes and measures. Though it is vitally important to provide electricity to customers, neither company believes that doing so is worth […]

Visiting power plants is one of the perks of being a COAL POWER editor. Some plants are located in metropolitan areas; others are closer to east nowhere, especially those mine-mouth plants. Each is unique and worth the travel time to visit and meet plant staff.

The web: Ideal for skills development / Upgrading a New Orleans pumping station / Turn plant failures into successes

The NERC auditors are coming / Winning encore for on-line pH monitoring / Using baloons as temporary barriers / How data logging can cut power bills

To make the most of their digital devices and enable the sharing of data by different departments, new and old plants alike need a reliable digital data infrastructure.

The U.S. is home to more than 30 boiling water reactors of BWR-3 through -6 vintage. At one time or another, all have experienced obsolescence, reliability, or control problems with their reactor recirculation flow control systems and components. Temporary down-powers are often required for corrective maintenance. Exelon Nuclear plans to begin upgrading the recirculation pump motor drives at its BWRs in the spring of 2009. The upgrade project’s technical design and business case were developed in great detail before the project was approved. This article presents the results of all key internal analyses.

While noting marginal improvements since last year, America’s power reliability watchdog recently warned that the nation’s growing thirst for electricity will still far exceed planned increases in generation capacity over the next 10 years, and that reserve margins could dip below optimal levels within two or three years in California, the Rocky Mountain states, New […]

The National Coal Council estimates that 40,000 MW of additional generating capacity is available to existing U.S. coal-fired plants simply by making efficiency improvements. Because decreases in production costs go straight to a plant’s bottom line, efficiency projects usually have short payback periods, especially if implemented in concert with mandatory environmental upgrades. One often-overlooked consequence […]

Why bypass desuperheaters fail; DSSP, CAD, and fast casting salvage nearly totaled pump; Seals of approval; Making gas turbine plants quieter

Replace pumps, cut repair bills / New bolts show their stress level / Up a certain creek, without a filter / Hang up those cables and hoses

Every step forward in underground U.S. mine safety in the 20th and 21st centuries has been on the backs of mangled and dead coal miners. That grisly observation is unassailable. Following the August tragedy at the Crandall Canyon mine in Utah that killed six miners and three would-be rescuers, the federal Mine Safety and Health […]

Since ratification of the Clean Air Act (CAA) in 1970, U.S. utilities have made steady efforts to install pollution control equipment to curb power plant stack emissions. The CAA Amendments of 1990 raised concerns at the time about the industry’s ability to install a large number of flue gas desulfurization (FGD) systems, or scrubbers, in […]

In Part I of this two-part report ( COAL POWER, July/August 2007, p. 22), we introduced the integrated R&D effort by the U.S. Department of Energy’s National Energy Technology Laboratory (DOE/NETL) to improve understanding of the mechanisms of mercury (Hg) capture and retention in flue gas desulfurization (FGD) systems and the fate of Hg in […]

Stop valves from leaking money / Integrating plant and equipment models / Pricing priceless knowledge

MidAmerican Energy Co. and its project partners are convinced that supercritical coal-firing technology’s inherently higher efficiency and lower CO₂ emissions no longer come with a price: reduced reliability. Their Walter Scott, Jr. Energy Center Unit 4, the first major new supercritical plant in the U.S. in more than 15 years, is POWER’s 2007 Plant of the Year.

By design, combined HP-IP turbines have a small amount of internal leakage from the high-pressure turbine to the intermediate-pressure turbine. As turbines age, the leakage increases considerably and becomes excessive, creating a heat rate penalty and possibly a reliability problem. Last month we explored the symptoms and causes of steam leakage within GE steam turbines and how to correct the problem. In Part II, we examine the same issues for Westinghouse and Allis-Chalmers turbines from both theoretical and practical angles.

Several states have mandated faster and/or deeper reductions in plant mercury emissions than those called for by the Clean Air Mercury Rule. Unfortunately, differences between plants make accurate evaluation of control options difficult. In most cases, even statistically based Hg emission models don’t pass muster because they don’t account for the dynamic chemical behavior of Hg species in gas cleaning systems. This article describes one system evaluation tool that has been validated using Hg field test data from 50 full-scale flue gas cleaning systems. It is already being used by TVA and other utilities.

Have you bought electrostatic or agglomeration equipment to rid your turbine oil of varnish deposits, but its varnish potential rating failed to improve? Or, after an initial drop, has the varnish potential returned to its previous level? Even worse, have you had recurring valve sticking problems after making a sizeable investment to "solve" this problem? Welcome to the world of soluble varnish caused by autodegradation. Read the unvarnished truth about varnish and how to get rid of it for good.

When injuries or accidents occur, the employer ultimately loses on two counts: increased medical costs and employee absences. A policy of "safety, compliance, and then production" is more than just good business; it’s also good stewardship of the health and safety of employees who deserve no less.

Hydro-demolition speeds reactor dome entry;
Tips for keeping your unit stable;
Air makes heavy move a breeze

The U.S. Department of Energy (DOE) and Great River Energy are testing a new coal-drying technology that could dramatically reduce the emissions of lignite-burning power plants. The project was selected for funding during Round I of the DOE’s Clean Coal Power Initiative (CCPI), a series of competitions to demonstrate a range of promising clean-coal technologies. […]

Lawrence Energy Center (LEC) proudly hosted about 60 representatives of the Powder River Basin Coal Users’ Group (PRBCUG) at its July 24th open house, luncheon, and plant tour. LEC was named the PRBCUG’s 2007 Plant of the Year at this year’s ELECTRIC POWER Conference and Exhibition in Chicago, May 1 – 3. Traditionally, the winning […]

The 1990 amendments to the Clean Air Act require coal-fired power plants to reduce their emissions of the pollutant SO2. To do so, many have switched to, or are considering switching to, Powder River Basin (PRB) coal. Unfortunately, PRB coal has a tendency to leave excessive and tenacious deposits on boiler heat-exchange surfaces. Complicating the problem, the distribution of the deposits is far from uniform.

Ready for your NERC close-up? / Synthetic oils for industrial applications

At the heart of most boiler combustion control systems (and most coordinated boiler/turbine control systems as well) is throttle pressure correction, usually applied by the "master controller." Throttle pressure is considered a key variable to control because it represents the energy balance between the boiler and the turbine. When throttle pressure is constant, the boiler […]

Cyber security and the grid; Harnessing the Yangtze;

Hydraulic system overhaul;

O&M problems not caused by cycling;

During 2005, about 150 million tons of coal were transported to power plants by hopper barges plying U.S. inland waterways. With coal-fired plants expected to continue producing 50% of America’s electricity, coal barge traffic is not likely to fall off. In fact, it may increase, for two reasons. One is cost. Shipping coal by barge […]

The Fayette Power Project (FPP, aka the Sam K. Seymour Power Station) is a three-unit, coal-fired generating plant sited near La Grange, Texas (Figure 1). Units 1 and 2, each with a nominal rating of 600 MW, are co-owned by the Lower Colorado River Authority (LCRA) and Austin Energy (AE). LCRA is a conservation and […]

Reducing NOx emissions from large utility coal-fired boilers has been a primary focus of the U.S. power generation industry since passage of the 1970 Clean Air Act and subsequent legislation. By the early 1990s, nearly all such boilers had installed some form of low-NOx burner (LNB) technology and/or overfire air (OFA) — the least expensive […]

Part I of this three-part series (POWER, October 2006) explored the negative impacts of sulfur trioxide (SO₃) on the operations and maintenance of back-end plant equipment. Part II (February 2007) listed and quantified the likely and potential benefits of limiting the concentration of SO₃ in flue gas to 3 ppm at the entrance to the air heater. This final part describes the characteristics of an optimal SO₃ removal technology and details the operating experience of a patented process that has worked successfully at a half-dozen plants for up to three years.