Plants using nuclear, municipal waste and coal are this year`s `Project of the Year Award` winners
All of this year`s `Project of the Year Award` winners have one thing in common–excellence in design, construction and operation
By Douglas J. Smith
Lee County Solid Waste Resource Recovery Facility, Fort Myers, Fla., USA; Yonggwang Nuclear Power Plant Units 3 and 4, Republic of Korea; and the Logan Generating Plant, N.J., USA, have been chosen by Power Engineering and Power Engineering International`s panel of judges to receive 1995 “Project of the Year Awards” for their excellence in design, construction and operation. The awards recognize excellence in the design, construction and operation of power generation and transmission systems throughout the world.
Each year the magazines request the designers, owners, operators and suppliers of power plant equipment to submit their entries for consideration by the magazines` independent panel of judges for “Project of the Year Awards.” The awards symbolize what is best in power plant technology and engineering.
Evolutionary PWRs installed in Korea
Korea Electric Power Corp.`s (KEPCO) Yonggwang nuclear power Unit 3 is reported to be the most advanced nuclear unit on-line in the world. Unit 4 is scheduled for completion in December 1995. The Yonggwang project is the only international project chosen by our panel of judges. Sargent & Lundy, Chicago, Ill., USA, and Korea Power Engineering Co. (KOPEC) were jointly responsible for the architect-engineering for Yonggwang project`s Units 3 and 4.
According to Sargent & Lundy and KOPEC, the project incorporates state-of-the-art technology in an evolutionary pressurized water reactor (PWR) plant. Sargent & Lundy provided lead engineering preliminary design for Phase I and detailed design support in Phase II. In addition, Sargent & Lundy provided a comprehensive transfer-of-technology program. Essentially, this program involved the training of Korean personnel in the United States and Korea and the transferring of nuclear power plant design technology.
The Yonggwang units will serve as the basic model for the development of a Korean standard nuclear power plant. Four additional units based on the Yonggwang Units 3 and 4 are already under design or in construction. These are the Ulchin Units 3 and 4 and two additional units, 5 and 6, at the Yonggwang site. Design of the two additional units, Units 5 and 6 at Ulchin, will start soon.
A new generation of nuclear technology
Sargent & Lundy said that the Yonggwang Units 3 and 4 represent a new generation in nuclear technology and are significant achievements for the nuclear power industry worldwide. The Yonggwang project is the first to have the nuclear units constructed using the Electric Power Research Institute`s advanced light water reactor (ALWR) program requirements as part of the design input.
What is even more significant, said Sargent & Lundy, is that the project was completed in eight years. In addition, it only took four years and months from first concrete to fuel loading. This clearly demonstrates that first-of-a-kind units can be built with accelerated schedules and controllable competitive costs, said Sargent & Lundy. The plant`s designers also said that decades of worldwide nuclear design, construction and operating experience based on the previous generation of US and Korean nuclear power plants have been incorporated into the Yonggwang units.
Equipment was manufactured in more than eight countries using specifications developed from US codes and standards. However, allowances were made for the use of other international standards that were shown to meet specific technical requirements. Major equipment suppliers for the Yonggwang project included:
– Asea Brown Boveri-Combustion Engineering (ABB-CE) and
– General Electric (GE).
The nuclear steam supply system was designed by Korea Atomic Energy Research Institute and ABB-CE and was supplied by Hanjung and ABB-CE. Hanjung and GE supplied the steam turbines and generators.
Because the redundant safety features are generally separated, equipment location, cabling and safety analyses were simplified. Subsequently, the time required for installation and analysis in safety-related areas was reduced.
The design largely eliminated fire wrapping and fire proofing, fire and flood seals, pipe whip restraints and jet impingement shields. These are not only costly to purchase, but also have high maintenance costs. Another design feature is that the equipment has been arranged so that areas normally accessible for maintenance have been separated from high-radiation and potentially contaminated areas of the plant. Thus, radiation exposure is minimized during maintenance and operations.
During the plant`s design, emphasis was placed on optimizing the placement of equipment to minimize piping and cabling distances. However, the designers made sure there was sufficient room for construction and maintenance. To verify equipment layout prior to construction, a three-fourths-inch to one-foot scale model of the plant was used. The number of piping supports at Yonggwang is half that used on earlier nuclear power plants. Except for the pressurizer surge line, all large bore piping snubbers have been eliminated.
The codes and standards used in the design of Yonggwang nuclear power plant`s Units 3 and 4 are consistent with current US practices and US Nuclear Regulatory Commission requirements. For this reason, the plant is a valuable reference point for any future new nuclear power plant design, said Sargent & Lundy.
Under budget and two months ahead of schedule
The Lee County Solid Waste Resource Recovery Facility was completed two months ahead of schedule and under budget. For the first nine months of 1995 the plant processed 249,459 tons (t) of refuse and recovered 7,251 t of ferrous material with a boiler viability of more than 97 percent (Table 1).
Because of increasingly stringent environmental regulations and dwindling landfill capacity, Lee County, Fla., USA, decided in the late 1980s to pursue resource recovery as its primary means of solid-waste disposal. By 1990 the County had chosen a 47-acre site in eastern Fort Myers for the construction of a 1,200 tons per day (t/d) waste-to-energy facility. Ogden Martin Systems Inc. was selected to design, construct, operate and maintain the facility. Malcolm Pirnie Inc. was selected to assist Lee County with final permitting, construction monitoring, overseeing of the facility`s acceptance tests and operating monitoring services. The facility serves not only Lee County, but also neighboring Hendry County. Construction of the Lee County Solid Waste Resource Recovery Facility began in October 1992.
During plant construction, more than 1,000 load-bearing piles were driven into the ground to support the facility`s structures. In addition, approximately 207,000 yards of fill were added to raise the site three-and-a-half-feet. Likewise, because the site is surrounded by wetlands, a two-foot earth berm had to be constructed around the site, and five retention ponds were constructed to contain any stormwater runoff.
The Lee County waste-to-energy facility is equipped with two 600-t/d mass municipal-waste combustors that utilize Martin reverse-reciprocating stoker grate and combustion-control technology. Steam is generated by two 169-klb/hr (million pounds per hour) Distral waterwall boilers. Control of the plant is through a Bailey Infi 90 distributive control system. Air-pollution control equipment, supplied by ABB, includes dry gas scrubbers, fabric filter baghouses, and mercury and nitrogen oxide abatement systems.
An Ogden continuous emissions monitoring (CEM) system monitors the plant`s emissions of CO, O2, NOx and SO2, as well as opacity. The CEM system also monitors total steam production, electric power generation, ammonia injection rate, slaked lime and activated carbon usage, combustion efficiency, and stack and combustion-zone temperatures.
A condensing extraction steam turbine, in addition to supplying auxiliary steam to the plant`s air heaters, air ejectors, deaerator and LP heaters, drives a 39.7-MW air-cooled, synchronous electric generator. Secondary treated waste-water is used in the condenser. Net electric power produced by the plant is stepped up to 138 kV and sold to Florida Power and Light Co. Fly ash produced by the plant is transported by an enclosed conveyor system to a Martin ash discharger, where it is combined with the bottom ash. A “grizzly scalper” and magnetic separator recover ferrous material from the ash.
First fires occurred on Aug. 24, 1994, and Units 1 and 2 steam-turbine generators were started on Sept. 2 and 3, 1994, respectively. Acceptance tests were carried out from Oct. 17-26, 1994. According to Ogden Martin, all the contract`s guaranteed performance criteria was exceeded by relatively wide margins, and the plant`s start-up proceeded with only minor problems. Commercial operation of the Lee County Resource Recovery Facility commenced on Dec. 1, 1994.
Since going into commercial operation, the plant has recorded 100-percent compliance with all environmental permits and regulations and has operated at zero-water discharge. Thomas Eriksen, the plant`s facility manager, said the major reason this plant was submitted for consideration for Power Engineering and Power Engineering International`s “Project of the Year Awards” is the facility`s long-term, environmental, social and economic solution to waste disposal. Instead of burying garbage in the ground, this plant uses garbage to cleanly generate electricity to serve the needs of approximately 25,000 homes, Eriksen said. The end result is that the incoming garbage is reduced to an inert ash residue that is just 10 percent of its original volume. Approximately 25 t/d of ferrous is recovered.
The Lee County plant has several innovative aspects with the most notable ones being its air-pollution control system, its ecologically sound reuse of treated waste-water and its extensive wetlands protection and mitigation elements. According to Ogden Martin, the Lee County facility is the first permitted and commercial operational plant in the United States with a permanent activated carbon-injection system for controlling emissions of mercury. The environmental control systems have been designed in anticipation of new, more stringent Clean Air Act requirements and have met the proposed standards without any modifications.
The Lee County facility also provides a long-range benefit to area-wide water resource management. Treated waste-water effluent, supplied by the City of Fort Myers, is used for the plant`s cooling tower make-up. As a result, water consumption is reduced in the eastern part of the county, and in the long term will aid in future conservation efforts in the area. Utilizing reclaimed waste-water for cooling also conserves critical groundwater resources.
Pulverized-coal-fired cogeneration plant is a winner
Logan`s 225-MW cogeneration plant (Figure 1) is located along the Delaware River in Logan Township, N.J., USA. The plant is fueled with high-quality, low-sulfur, pulverized coal. All of the plant`s electric output is sold to Atlantic Electric, and the neighboring Monsanto plant purchases up to 50,000 lb/hr of process steam.
Although originally conceived as a “Qualifying Facility” under the Public Utility Regulatory Policies Act of 1978, the plant`s status was changed to an “Exempt Wholesale Generator” with passage of the Energy Policy Act in 1992. Commercial operation of the plant started on Sept. 22, 1994. The Logan cogeneration plant was developed, and is now managed, by US Generating Co., a partnership of PG&E Enterprises (PG&EE) and Bechtel Enterprises Inc. (BEn). PG&EE is the non-utility subsidiary of Pacific Gas and Electric Co., and BEn is a unit of Bechtel Group Inc. The Logan plant is owned by Logan Generating Company L.P.
According to US Generating Co., the plant`s design reflects a dedicated concern for environmental and aesthetic considerations, as well as the needs of the community. Because of concerns in regard to train traffic and noise by the community, US Generating Co. agreed to have the coal delivered to the plant by barge along the Delaware River rather than by train.
Because of environmental concerns, the clamshell unloading and conveyor system was constructed one-half mile offshore. Wind curtains and dust collectors were also installed in the clamshell unloader and receiving hopper. Likewise, to prevent fugitive emissions during the coal`s trip from the barge to the plant`s enclosed active coal storage building, a sophisticated enclosed coal-transport system was installed.
Environmental protection very important
US Generating Co.`s major emphasis was protection of the environment, and to accomplish this, advanced air emissions and water-quality controls were installed at the Logan plant. The Logan plant is reported to be only the second pulverized-coal-fired plant in the United States to use selective catalytic reduction (SCR) NOx control. According to the plant`s operators, Logan`s SCR system effectively reduces the emissions of NOx to the lowest levels ever permitted on a US pulverized-coal plant–0.17 lb/MBtu (Figure 2).
SO2 emissions are reduced through the use of a spray dryer absorber system. The plant`s permit allows for SO2 emissions of 0.16 lb/MBtu. As previously mentioned, fugitive emissions from the coal are contained by providing enclosed structures for all major areas of the coal-handling systems. Particulates in the flue gas are removed in the plant`s baghouse. The baghouse has advanced fabric filters that limit the particulate dust emissions to a rate of 0.018 lb/MBtu.
Like most modern plants, Logan cogeneration plant incorporates an advanced zero-discharge water-treatment system. This system not only prevents any process water from being discharged into the Delaware River, but also reduces the plant`s water intake from the river by approximately 40 percent. Similar to the Lee County project, the Logan plant`s design incorporates wetlands mitigation, containment and processing. To accomplish this, lined ponds and miscellaneous curbs, swales and grading have been installed. Thus, any leakage, spill or runoff is directed to the appropriate process area for treatment and reuse.
All of the waste-water is processed in a reverse osmosis (RO) unit. After treatment, some of the water is pumped to demineralizers for further purification prior to being used for boiler water make-up. The remaining RO-treated water is used for cooling-tower make-up, while the non-recyclable RO brine is evaporated via the spray dryer absorber.
POWER-GEN Americas `95
POWER-GEN Americas `95, in Anaheim, Calif., USA, will be the venue for the awards ceremony. Owners of the plants–Lee County, Korea Electric Power Corp. and Logan Generating Company L.P.–will receive their awards at the keynote session to be held at the Anaheim Marriott hotel, 9:00 a.m. to 11:30 a.m. on Tuesday, Dec. 5, 1995. Major vendors to the awarding-winning projects will receive awards at a special luncheon to be held during POWER-GEN Americas `95. Date and location for the luncheon is not available at this time.
Yonggwang Unit 3 reactor vessel ready for installation.
Lee County Solid Waste Resource Recovery Facility, Fort Myers, FL, USA.
225-MW Logan Generating plant, New Jersey, USA.
Yonggwang Unit 3 reactor vessel being lowed into position.