The crowning jewel

After 10 years of planning, permitting and building, the Solid Waste Authority (SWA) of Palm Beach County held the grand opening of its new waste-to-energy (WTE) facility, the Palm Beach Renewable Energy Facility 2 (PBREF 2) in late June.

The facility, owned by the SWA and located in West Palm Beach, Florida, was designed, manufactured and constructed by a consortium of Babcock & Wilcox (B&W), headquartered in Charlotte, North Carolina, and KBR Inc., Houston. It is considered by the companies to be the cleanest and most advanced power plant of its kind in North America. The SWA and the consortium celebrated the facility’s grand opening with a ribbon cutting ceremony on June 27.

B&W designed and manufactured the plant’s three mass-burn, WTE boilers, capable of generating up to 95 megawatts of electricity, and its environmental control system. The plant features DynaGrate air-cooled and water-cooled combustion grates designed by B&W Vølund and will be operated under a 20-year agreement by B&W’s subsidiary, Palm Beach Resource Recovery Corp., which has operated the adjacent PBREF 1 since 1989.
 

An occasion to celebrate

During the grand opening, Paul Scavuzzo, B&W Global Power Division vice president said, “We would like to thank and congratulate our customer, the SWA, as well as our consortium partner KBR, for a job well done. The PBREF 2 is truly B&W’s flagship project in North America and a shining example of the game-changing potential of waste-to-energy technology.”

Scavuzzo continued, “Plants like PBREF 2 not only provide valuable energy while drastically reducing the amount of waste we bury, but are also a valuable asset in reducing greenhouse potent gas emissions caused by methane generated in landfills. With advanced emissions control systems of the kind we installed, these plants can also generate that power cleanly.”

Ray Schauer, SWA director of engineering and public works, remarked, “The completion of this state-of-the-art facility represents the culmination of a 10-year effort that virtually ensures to the taxpayers of Palm Beach County that their solid waste will be disposed of in the most efficient and environmentally sensitive method available in the world today long into the future.” Schauer called PBREF 2 “a jewel in the crown of SWA’s award-winning integrated solid waste management system that will set the standard for performance and environmental sustainability in North America.”

What is also remarkable, according to Schauer, was the commitment by several entities to complete the project. “During the struggles of an economic downturn, our partners delivered on their promise to spend locally, with more than $136 million spent with businesses in Palm Beach County and more than $35 million spent with small businesses; and to hire locally, by using more than 1.1 million hours of construction labor by Palm Beach County residents,” he said.
 

Part of a bigger plan

SWA was featured in the cover story “Long-term Solution” in the September/October 2013 issue of Renewable Energy from Waste.

The article notes that SWA’s first waste-to-energy facility Palm Beach Renewable Energy Facility No. 1 (PBREF 1), built in 1989, requires preprocessing of waste to produce a refuse-derived fuel (RDF) before it is fed into boilers. The new facility uses mass-burn technology and doesn’t require preprocessing. The shift from RDF to mass-burn is a result of the extensive curbside recycling program that has been put in place since PBREF 1 was built, according to Mark Hammond, SWA director. “Pretty much the way people put it onto the curb is the way it is put in the boilers,” he explained of the new facility in the article.

According to Larry Hiner, B&W boiler product line manager, the PBREF 2 facility features several advancements in waste-to-energy technology that make it “the cleanest and most state-of-the-art facility in North America, and perhaps the world.” The first is this mass-burn plant’s advanced combustion controls.

“The system utilizes the B&W Vølund DynaGrate grate system that controls the drying and combustion of waste. Combined with the advanced Precision Jet overfire air system, it effectively eliminates carbon monoxide, dioxin and furan emissions within the combustion zone of the furnace,” he says.

B&W also uses a spray dryer absorber system combined with activated carbon injection to reduce acid gas emissions like hydrogen fluoride (HF), sulfur dioxide (SO2), and hydrochloric acid (HCl) as well as effectively capture any heavy metals that are present in the flue gas stream. The unit is also equipped with an advanced clean side selective catalytic reduction (SCR) reactor that eliminates nitrogen oxides (NOx) emissions by reacting the NOx with ammonia, resulting in the lowest controlled NOx emissions on a WTE facility. Hiner says the SCR technology is the first installed on WTE in both the United States and the world. “The unit just completed all performance and emissions testing and met all of the very stringent project requirements,” he notes.

According to Hiner, the primary differences between the PBREF 1 and PBREF 2 are the DynaGrate grate system and the associated advanced combustion controls related to this system being used PBREF 2.

The fuel for the PBREF 2 facility is managed in the storage area through the use of automated crane operation. “This automation provides very thorough mixing and uniformity of the waste that further promotes good combustion practices. This is the first installed installation of this technology on a new facility in the U.S.,” says Hiner.

The other major pollution control difference in the design is the addition of the SCR in lieu of a selective noncatalytic reactor (SNCR). SNCR is limited in reducing NOx emissions compared to a SCR design. The other major feature of the PBREF 2 design is the ferrous/nonferrous metals recovery. B&W was able to guarantee and demonstrate ferrous metals recovery of greater than 90 percent and nonferrous recovery of greater than 85 percent on postprocessed material, says Hiner.

Ground broke on the PBREF 2 in April 2012. PBREF 2 includes three boilers, each capable of combusting 1,000 tons per day. It generates an additional 45,000 megawatts of electricity per month, enough to power 44,000 homes. The new facility features separation postcombustion to remove ferrous and nonferrous material from the ash. The new facility is reportedly the first mass-burn WTE facility to be constructed in the United States in more than 15 years.

In the 2013 article, Hammond attributes the support of the project to the successful operation of the first facility. “Having had an existing facility in operation for 20-plus years operating extremely well, I think most people were just comfortable with it and could see it is really not a problem,” he says.

PBREF 2 is located on 24 acres adjacent to the county’s original WTE facility, also designed and built by B&W. PBREF 2 will provide power for an estimated 44,000 homes and businesses while processing more than 1 million tons of postrecycled municipal solid waste each year. This will reduce reliance on the landfill by up to 90 percent, while also recycling an estimated 27,000 tons of steel, aluminum, copper and other metals annually, according to SWA.

Hiner says, “With the refurbishment of the PBREF facility after operating for 20 years to allow for an additional 20 years of operation, B&W believes that PBREF 2 will continue to provide the Palm Beach County community with operation for the next 20 years and beyond.” He says B&W is committed to providing the operation and maintenance contract for the facility and takes this responsibility to the county as its first priority to maintain the successful operation of both facilities.

“The commercial operation of Palm Beach Renewable Energy Facility 2 is the crown jewel of the Solid Waste Authority of Palm Beach County’s long-term integrated solid waste master plan that will ensure the safe and sustainable management of all the waste generated in Palm Beach County for decades to come,” SWA says in a statement. “For starters, it will help the SWA achieve the state’s 75 percent recycling goal well ahead of the 2020 deadline. It will also mean that only inert inorganic material will be landfilled, virtually eliminating the production of additional greenhouse gases. Palm Beach County is well on its way to become a national model for responsible, cost effective solid waste management.”

Information in this article was provided by the Solid Waste Authority of Palm Beach County, West Palm Beach, Florida, and of Babcock & Wilcox, headquartered in Charlotte, North Carolina.