The absorber rings weigh between 120 and 361 tons (109 and 327 t) each, are 14 to 35 ft. (4.3 to 10.7 m) in height, and 72 ft. (22 m) in diameter. They are transported to the site via the Tennessee-To
FirstEnergy will complete “one of the largest retro-fit projects in history” at its coal-burning electric generation W. H. Sammis plant in Stratton, Ohio, in 2011. The $1.5 billion project is expected to reduce emissions of sulfur dioxide by 95 percent and nitrogen oxide (NOx) by at least 64 percent. To reach these goals it is installing emission reducing technology known as Selective Non-Catalytic Reduction (SNCR).
Stratton is between East Liverpool and Steubenville in southeastern Ohio.
Current renovations and construction have been designed and are being managed by Bechtel Power, one of the world’s largest engineering firms. The site includes Block 7 — home to one of the tallest chimneys in the world, which was built in 1970. The power plant includes a tunnel for State Route 7, a four-lane freeway. The tunnel goes under the Baghouse structure, which filters particulate and toxic gases from the exhaust before entering the smoke stack.
The Sammis facility is the largest of FirstEnergy’s coal-fired power plants in Ohio. The plant sits on 187 acres along the Ohio River and consists of five oil-fired peaking units and seven coal-fired units, and produces 2,233 megawatts of electricity —enough to serve about 1.3 million homes.
Construction of the first four coal-fired units were built between 1959 and 1962 with the remaining three units being completed in 1967, 1969 and 1971.
Part of the SNCR involves installing “scrubbers” on all seven coal-fired units before 2011. Scrubbers, the size of skyscrapers, have been built by the Bruce Mansfield plant of Shippingport, Pa., and take up to three weeks to move via the Ohio River to Stratton.
“The scrubber rings were designed and engineered by Babcock & Wilcox, of Barberton, Ohio,” FirstEnergy spokesman Mark Durbin said. They were fabricated by PSP Industries of Fulton, Miss.
Constructed of stainless steel alloy, the scrubber absorber rings have been stacked, six on top of each other, to form three 159-ft. (48 m) tall absorber towers. The absorber rings weigh between 120 and 361 tons (109 and 327 t) each, are 14 to 35 ft. (4.3 to 10.7 m) in height, and 72 ft. (22 m) in diameter. They are transported to the site via the Tennessee-Tombigbee Waterway. The staging area is at Paducah, Ky.
The Army Corps of Engineers coordinated scrubber ring deliveries as the locks on the Ohio River must be closed while the deliveries are taking place. A specially built ramp near the locks facilitates off-loading. A 120-wheel Goldhoffer transporter backs onto the barge. Traffic on SR 7 is stopped in both directions for the transporter crossing.
Equipment to control NOx is to be installed no later than 2012. The majority of the new equipment will be located south of the plant, according to FirstEnergy’s fact sheet for the project. Pilings are being sunk and ductwork is being constructed along the deck and around the south yard. A “hollow rock” waste disposal facility for the scrubber byproduct will be built on former strip mine near the plant.
Compared to other NOx removal technologies, SNCR power plant installation is simple and easy, according to FirstEnergy press releases.
“SNCR injects a chemical substance, such as ammonia or urea, into the flue gas. The system then reduces NOx by breaking it down into three ingredients: nitrogen, carbon dioxide and water vapor. In certain temperatures, 30 percent of NOx can be reduced from flue gas using this process.”
A new 850-ft. (259 m) stack has been completed. The ammonia facility has been completed and is being used as a catalyst for NOx control. Pre-fabricated pieces of the ductwork, weighing up to 100 tons (91 t) each have been delivered by barge —100 barge deliveries. Fiberglass flues for each of the vessels are in place, as is the steelwork for the Selective Catalytic Reduction (SCR) equipment.
Constructed on-site is a hollow rock waste gypsum disposal facility, built on a reclaimed strip mine. Limestone is used as a reagent to remove SO2 from the emissions, converting it to synthetic gypsum. The synthetic gypsum is dried and then transported to the facility via a 2.4 mi. enclosed conveyor belt. Approximately 578,000 tons (524,353 t) of limestone will be used annually.
Project Scope and Scale
• Approximately 1,400 workers, 5 million hours needed to complete project overall
• Flue Duct Work — 9,000 ft. (2,743 m)
• Support Pilings — 6,000 – equals 480,000 lineal ft. (146,304 m) — more than 90 mi.
• Concrete — 52,400 cu. yds. (40,063 cu m) — nearly enough to build a sidewalk from the plant to Washington D.C.
• Structural steel — 15,000 tons (13,608 t) — enough to build 97 Statues of Liberty
• Electrical Cable – 10,400 circuits, 568 mi. — distance from Stratton, Ohio, to Savannah, Ga.
The plant uses an average of 18,000 tons (16,329 t) of low and medium sulfur eastern coal daily for an annual average of 6.6 million tons (6 million t). A 45-day supply of coal is maintained at the plant, in a stockpile covering more than ten acres. The plant employs 410 people and is the largest taxpayer in Jefferson County, paying $5.5 million in property taxes annually.
Pickering Associates of Athens, Ohio, has provided architectural and engineering design services for several projects at this facility, including the new waste water treatment building. According to the Web site, “this project was unique in the incorporation of sixteen monorails to be used in the operation of the facility. Special attention was required for the structural support and connections of the monorails to the building frame. This facility was also designed with future construction in mind, therefore a 40-ft. tall by 150-ft. long fire wall was necessary to separate the occupancies.”
According to FirstEnergy’s Web site, “FirstEnergy companies have spent more than $5 billion on environmental protection efforts since the Environmental Protection Agency’s Clean Air Act became law in 1970, and these investments are making a difference. Since 1990, FirstEnergy has reduced emissions of nitrogen oxides [NOx] by more than 65 percent, sulfur dioxide [SO2] by more than 55 percent and mercury by about 45 percent. Also, our carbon dioxide [CO2] emission rate, in pounds of CO2 per kWh [kilowatt hour], has dropped by 10 percent through this period.”
In 2005, the U.S. Environmental Protection Agency (EPA), announced a major Clean Air Act (CAA) New Source Review Program (NSR), and a settlement with Ohio Edison Company, a subsidiary of FirstEnergy Corp., in a suit brought against FirstEnergy Corp. by the EPA and the states of New York, New Jersey, and Connecticut. The suit alleged that the W.H. Sammis Power Plant violated EPA standards for air quality. Ohio Edison agreed to spend $1.1 billion prior to 2012 to “substantially decrease emissions at the Sammis plant and other nearby Ohio Edison plants.”
Under the settlement, an annual tonnage cap for SO2 and NOx emissions was set, which would decline over time.
“In the 1990s, EPA discovered that electric utility and oil companies had been carrying out massive, pollution-increasing construction projects to extend the operational lifetimes of the oldest, dirtiest power plants and oil refineries in the country. The power and oil companies had carried out these projects without adopting modern pollution controls or examining the impact of the increased pollution on downwind communities and parks, emitting hundreds of thousands of tons of illegal pollution,” according to a statement from the Natural Resources Defense Council (NRDC).
The W.H. Sammis plant was one of 16 coal-burning plants sued by the state of New Jersey. The state argued that these plants, all in the Midwest, “emitted 350,000 tons of NOx and 136 million tons of carbon dioxide …more than a million tons of sulfur dioxide, which causes asthma in people who breathe the air.”
Sprol, an online group that reported the “worst places in the world” said “Decades ago people believed that taller smokestacks would somehow dilute the pollution and make it less harmful, like blowing your cigar smoke up towards the ceiling in a crowded room. It works about as well, too. All it does is spread the smoke farther out.”
Sprol continued, “More than 145,000 tons of sulfur dioxide per year actually comes from this one facility, the W.H. Sammis plant, operated by Ohio Edison, which is owned by FirstEnergy Corporation. More pollution comes out of these chimneys than all of the power generating stations in New Jersey and Connecticut, combined.”
“Pollution from coal-burning power plants causes an estimated 30,000 deaths a year in the United States – more than drunken driving, AIDS, or homicides, according to one analysis,” reported in an analysis by Abt Associates of Cambridge, Massachusetts. The EPA has hired Abt “to quantify the health effects of federal policies.”
“By retiring older, less efficient coal-based generation units, swapping assets with other utilities and increasing the output of our nuclear facilities, we have avoided an average of nearly nine million tons of CO2 emissions annually since 1990. In fact, our generating output has increased nearly 15 percent in that time, while our overall CO2 emissions remain at 1990 levels. And, with nearly 40 percent of our electricity coming from non-emitting sources, we are well-positioned to compete in a carbon-constrained future,” reported FirstEnergy in a prepared statement.
FirstEnergy also is committed to a waste minimization. Scrubber sludge is used to make gypsum, which is then made into wallboard. CEG
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