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The Solid Waste Authority (SWA) of Palm Beach County, located in West Palm Beach, Fla., by all accounts is a model of a successful integrated waste management system. With recycling, composting, pelletizing and waste-to-energy capabilities, the SWA strives to capture as much value out of the waste stream as it possibly can.

The SWA is tasked with managing the waste disposal of Palm Beach County’s 1.3 million residents and 25,000 commercial customers. It also is responsible for waste collection in the county’s unincorporated areas, which make up about 50 percent of the county.

SWA Executive Director Mark Hammond will tell you, “We we may not have necessarily pioneered a lot of the disposal technologies that are out there, but we certainly have incorporated different techniques into our system.” He adds, “We take what we believe are some of the best methods out there and incorporate them into our operation.”

Situated on 1,300 acres of land in West Palm Beach, the SWA’s system for handling the county’s waste includes a landfill, a refuse-derived fuel (RDF) waste-to-energy (WTE) facility, a composting facility, a biosolids pelletizer, yard waste processing operation, a household chemical drop-off facility and a material recovery facility. SWA also owns six transfer stations throughout the county.

“We have many ways to deal with solid waste, from recycling to waste-to-energy, so that at the end of the day as little material goes into the landfill as possible,” explains Hammond. The biosolids pelletizer turns sludge from the wastewater treatment plant waste into a fertilizer additive. The pelletizer uses landfill gas as energy in its drying process.

The SWA generates revenue in four main ways: by a tax assessment on residents in which the cost of collection is added on for residents in unincorporated areas; through the sale of recyclables; through electricity generation at the WTE facility; and tipping fees. As a way to encourage recycling for businesses, the SWA charges a tip fee to its commercial accounts for landfill disposal.

Ahead of the Curve
Hammond began his career in solid waste in Upstate New York back in the 1970s, at a time when he says every community had its own landfill. New York began to require counties take responsibility for solid waste disposal. Within 10 years, Cattaraugus County, New York, closed more than 300 community and private dumps, constructed two landfills and began a recycling operation and WTE facility. Hammond then decided to put his expertise to work in West Palm Beach.

“I came down here in 1983 and did it all over again,” says Hammond. He says, at the time, New York state was ahead of the curve in its management of solid waste. “When I came down here, all we had were landfills, so we did the same thing: We upgraded the landfills, we built the waste-to-energy facility and transfer stations.

The transfer station allows for mass transfer of garbage and cuts down on traffic entering the disposal facility. “If you can keep those trucks out on the route, it is more efficient,” Hammond says. “If they have to drive longer distances to go to the disposal facility, it makes it much less efficient.”

The Palm Beach Renewable Energy Facility No. 1 (PBREF 1) was built in the 1989. It is operated by Palm Beach Resource Recovery Corp., a subsidiary of Babcock & Wilcox Power Generation Group Inc., Barberton, Ohio. Hammond notes that of the two types of waste-to-energy technologies that existed at the time—mass burn and refuse-derived fuel (RDF)—SWA decided on RDF. Producing RDF requires preprocessing of material prior to combustion. At the time, Hammond notes, the county did not have an extensive recycling program.

“The plan and the vision was to pull materials out prior to combustion. That is why we selected RDF,” he says. “We have several processes to pull out noncombustibles such as ferrous, nonferrous and glass. Then it is sized between 2 and 6 inches and fed into the boilers.”

The WTE facility has two boilers with a combined capacity to use about 2,200 tons per day of RDF to make electricity. It produces about 34,000 megawatt hours per month of electricity. Through a power patch purchase agreement with Florida Power and Light (FPL), SWA receives $57 per megawatt hour. In 2013, SWA renewed its agreement with FPL for another 20 years.

“They are required by law to buy our power,” he explains “But the state has to approve the contract. They are required to not pay more than avoided cost. They can’t pay us more than they could make it for or acquire the power for from other sources.”

The Next Phase
When SWA built its first WTE facility, the population of Palm Beach County was 600,000. Today that population has more than doubled to 1.3 million, and the state predicts the population could reach 1.7 million in the next 15 to 20 years.

SWA recognized it needed to address the future disposal needs of Palm Beach County residents and businesses. “Our existing landfill was scheduled, based on our models, to run out of space in the mid ’20s so back in 2005. Recognizing that our existing landfill was going to run out of space within 20 years, we started looking at additional landfill space,” recalls Hammond.

But plans to open a new landfill were not well-received. Even the environmental community was more in favor of expanding WTE than landfilling. “We kind of did a redirection at that point in 2005/2006 and began expanding our waste-to-energy capacity, and that is how we got where we are today,” says Hammond.

Ground broke on the Palm Beach Renewable Energy Facility No. 2 (PBREF 2) in April 2012. The new facility will use mass-burn technology and won’t require the preprocessing of the RDF facility. As Hammond describes it, “Pretty much the way people put it onto the curb is the way it is put in the boilers.”

The new facility will feature separation postcombustion to remove ferrous and nonferrous material from the ash.

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.

“It is voluntary, but we probably achieve 70-plus percent participation,” says Hammond of curbside recycling. He adds that the county has an aggressive commercial recycling program. “So if you have a good program in place, and you are pulling out as much of this material as you can prior to combustion, then going to a mass-burn facility doesn’t hurt your recycling program,” he explains.

PBREF 2 will include three boilers, each capable of combusting 1,000 tons per day. It will generate an additional 45,000 megawatts of electricity per month, enough to power 40,000 homes. Hammond says construction is about 50 percent complete.

The new facility is reportedly the first mass-burn WTE facility to be constructed in the United States in more than 15 years.

Hammond attributes the support of the project to the successful operation of the existing 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.

Even the U.S. Environmental Protection Agency recognizes WTE facilities have fewer problems associated with them than landfills, notes Hammond. “Landfills create methane, which is 21 times more potent a greenhouse gas than carbon dioxide, and you’ve got to deal with leachate.” He adds that pollution control equipment for WTE has greatly improved over the last 20 to 30 years.

Hammond says he expects PBREF 2 to be fully operational in May/June 2015, with test burns as early as fall of 2014. The new facility is expected to extend the life of the existing landfill by another 20 years, or until about 2047. In Hammond’s opinion, the real benefit of WTE is extending the life of the landfill. “Essentially WTE facilities are volume reduction machines that happen to produce power,” he says. “You wouldn’t build these strictly to produce power.”

When the new facility comes online, it will only be running at about 80 percent capacity. “Our board decided it wanted to build it for future growth,” explains Hammond.

SWA relies on flow control to ensure it has ownership of the waste for its WTE facilities. “The Supreme Court affirmed the right of public agencies to direct the flow to public facilities,” Hammond says. “You have to have that if you are going to make this kind of financial commitment to handle the waste. That ensures you have the waste to run the facility.”

Hammond says SWA’s goal is to be at 75 percent diversion when PBREF 2 comes online. SWA also is looking at ways to further reduce the material it landfills by reusing the ash produced from the incineration.

“There is always something at the end of the day that you can’t recover, burn or recycle, but our goal is to keep as much out of the landfill as we possibly can, given that it is cost effective,” Hammond says. “Properly disposing of solid waste is very important in Palm Beach County. Over 2 million tons are generated per year and it is a big responsibility to make sure it is handled properly.”

Hammond says of the SWA, “We take being stewards of the environment seriously. It is a challenge, but it is extremely rewarding.”

The author is managing editor of Renewable Energy from Waste and can be contacted at [email protected].