The waste conversion industry covers a spectrum of methods for turning waste into renewable energy and fuel, including anaerobic digestion (AD), mass-burn incineration and gasification. Harvey Gershman, president of Gershman, Brickner and Bratton Inc. (GBB), McLean, Virginia, said waste conversion remains a work in progress in the U.S., but interest in this technology continues to grow with the desire to divert more material from landfills.

Gershman was the initial panelist to present during the opening session on the U.S. waste conversion industry during the 2017 Renewable Energy from Waste (REW) Virtual Conference Oct. 3 and 4, 2017.

Of the nearly 350 million tons of waste that were managed in the U.S. in 2013, he said the majority—64 percent—went to municipal solid waste (MSW) landfills. Twenty-one percent of the remaining material was recycled, 9 percent was converted into energy and 6 percent was composted.

Gershman broke down U.S. waste management infrastructure by facility type. (See the table on page S6.) Transfer stations, which numbered 3,350 as of October, are replacing landfills in U.S. cities, he said. The country has 586 material recovery facilities (MRFs), more than 9,000 curbside recycling programs and roughly 70 mixed waste processing facilities and hybrid MRFs. Residential waste also is going to nearly 2,300 composting facilities, 75 waste-to-energy (WTE) facilities and 25 AD facilities throughout the country.

“[Anaerobic digestion] is the fastest growing segment of new assets in the U.S.,” Gershman said, adding that the U.S. was home to no AD facilities in 2000.

He also acknowledged the decline of traditional mass-burn WTE facilities, saying that number in 2000 would have been “around 120 or so.”

BIG FISH, LITTLE POND

Gershman said landfills are still the big fish in the little pond—almost 2,000 landfills are located throughout the U.S. “Landfills are getting bigger in size and they are consolidating a bit, but we still have one heck of a lot of landfill capacity and landfills around the country,” he said.

Approximately 220 million tons of MSW were landfilled in 2013. If diverted from landfill, that amount of material would have created a nationwide investment opportunity of $120 billion and 50,000 jobs, Gershman said. “This is a pretty good economic opportunity, not to mention the environmental benefits.”

Collection, processing and disposal costs were important factors to consider, he said. “If you have an inefficient collection system for the 60 percent of the cost of solid waste, you’ve got a real opportunity to make that more efficient in whatever the various ways are—technology, policies—to put more money into the processing and disposal.”

The average tipping fee at WTE facilities is $68 per ton, competing with an average tipping fee of around $50 per ton at a landfill. But, Gershman said, those landfill fees depend on location and have been increasing over time. Tipping fees can reach as high as $80 per ton in the Northeast, while they can be as low as $36 per ton in western states. In 2013, tipping fees in the Northeast were $75 per ton on average, while in western states they were around $34 per ton, he said.

“These are posted rates. Contracted rates for significant tonnages may even be less,” Gershman added.

GOING ORGANIC

Waste composition also dictates why companies and municipalities might want to move toward renewable energy generation. For example, the U.S. Environmental Protection Agency (EPA) estimates one-third of the MSW stream that remains after recycling is made up of food scraps (23 percent) and yard trimmings (9 percent).

“These two big organic pieces, plus contaminated paper, represent a very significant opportunity for anaerobic digestion or integrating into a more controlled composting system,” Gershman said.

More than 20 organics facilities are in the planning stages in the U.S. They are mostly being developed by commercial waste generators, he said. This is because of the low number of households that separate and collect organics at the curb. “We have a long way to go before we’re getting food waste out of the kitchen [and] into a separate garbage pail, put in a yard waste container or just collected separately,” Gershman added.

Organic waste can be integrated into what he describes as ever-changing energy generation methods, since renewable natural gas can be a product of anaerobically digested organics. “To make a long story short, new coal capacity is disappearing, and wind and solar have been added,” he said, adding that natural gas has made the most gains by far.

In addition, Gershman said, pricing for natural gas has remained at a steady $3 per dekatherm because of hydraulic fracturing. Power production from natural gas, he noted, surpassed coal in 2016.

WHAT TO USE

Gershman described mass-burn incineration as the “mainstay” of WTE plants. Considerable contenders in this field are Covanta, Morristown, New Jersey; Babcock & Wilcox, Charlotte, North Carolina; and Wheelabrator, Portsmouth, New Hampshire. These companies use steam generated from burning feedstock, such as yard waste and MSW, to create energy.

The newest mass-burn facility is in Palm Beach County, Florida. The Solid Waste Authority of Palm Beach County’s facility has been operating commercially since June 2015 and combusts 3,000 tons of MSW per day, Gershman aid. The Babcock & Wilcox facility produces 581.8 kilowatt hours per ton of material processed.

European firms that are licensors or developers of this technology account for the majority of AD facilities being built in the U.S. Typically, there are two types of AD—high solids and low solids.

Two recent AD facilities include CR&R in Perris, California, and Blue Sphere in Charlotte, North Carolina. CR&R is a $100 million facility processing 84,000 tons of organic waste per year. It’s a high solids system that takes in residential food and yard waste and commercial food waste to generate compressed natural gas (CNG) for fleet fuel and pipeline-quality natural gas. The $27 million Blue Sphere facility takes in 156,000 tons of animal and food waste per year to create electricity and soil amendment.

Gasification, Gershman said, has “people in it, out of it and one that used to be in it that’s coming back into it.” It entails a starved-air partial-combustion process that produces synthetic gas (syngas). The syngas can be used for fuels as well as for electricity and typically is created from MSW, biomass or agricultural waste.

Plasco Conversion Technologies, formerly known as Plasco Energy Group, recently reemerged with new owners, he said. In 2011, the company contracted with the city of Ottawa, Ontario, to build and operate a 110,000-ton-per-year plant to convert MSW into electricity. Now it focuses on selling technologies to municipalities with existing MSW facilities, Gershman said.

Another type of waste conversion is plastic-to-oil technology, sometimes referred to as pyrolysis. It can help with the difficult-to-recycle plastics that pop up in waste streams. Pyrolysis uses thermal conversion in the absence of oxygen.

Many waste conversion processes require feedstock preparation. Processing technology from companies including Van Dyk Recycling Solutions, Stamford, Connecticut; Machinex, Plessisville, Quebec; and Bulk Handling Systems (BHS), Eugene, Oregon, often are found at the front end of waste conversion systems.

An example of a mixed waste processing facility that used front-end processing to extract recyclables and fuel feedstock was the Infinitus facility in Montgomery, Alabama. The $35 million, 80,000-sqaure-foot facility closed in October 2015, a little more than a year after opening. Gershman said the facility did not shut down because of problems with the equipment or end-product quality but because of a bad contract that “didn’t allow for service fee adjustments due to market conditions.”

LOOKING INTO THE FUTURE

Gershman concluded by talking about the circular economy, which he said was all the buzz at the Wastecon/ISWA (International Solid Waste Association) World Congress in Baltimore in late September.

“Let’s try to make things here with our waste and use it here in the U.S. or North America rather than shipping it to other countries to convert it to products that we buy back,” he said.

With landfill prices rising and the desire for diversion growing, Gershman said, waste conversion has the potential to thrive in the U.S.”

“As a bottom line, let’s keep in mind that waste is recyclable but it’s also very renewable,” he said. “Every time I look out on my street on Friday in my neighborhood, there are garbage cans at the end of every driveway with more waste, so it just keeps coming back.

“A lot less waste going to landfill is a lot better, in my opinion,” he continued. “And if your waste isn’t recyclable and it’s not organic, then what is it? It’s fuel or feedstock for something.”

The author is assistant editor for Waste Today and can be contacted at hcrisan@gie.net.

The month of September was anything but ordinary for Florida residents. The threat of Hurricane Irma prompted the largest evacuation in that state’s history. When it finally did make landfall on the U.S. mainland Sept. 10, it brought with it winds with a strength that some had never experienced before.

The Renewable Energy from Waste Conference was planned for early October in Fort Myers, Florida. The area was among the worst affected parts of the state. Uncertainty regarding the state of the conference hotel and venue and the facility that was to be toured during the conference led us to cancel the event in its traditional form.

However, much of the planning and preparation for the conference did not go to waste. We were able to offer the event virtually. This solution was a way to provide the foremost knowledge available on waste conversion to those who were interested in learning about the subject. And, as it turned out, many of you were.

To all of our presenters, attendees and sponsors, thank you for your willingness to adapt to the new format and for logging into your computers Oct. 3 and 4 to join us for the conference. And thanks to our conference partner, Gershman, Brickner and Bratton Inc., who supported the decision.

Moving the waste conversion industry forward is only possible when outlets are available to share information. That is why we decided to offer this Renewable Energy from Waste Supplement to the November/December issue of Waste Today in addition to the virtual event.

We hope you gain the valuable insights that a face-to-face event would have provided through the package we have developed in its place.

One of the biggest challenges the waste conversion industry faces is securing financing. While government programs can help provide the cash infusion necessary to accomplish a waste conversion project, understanding which ones a project qualifies for can be complicated.

During the Renewable Energy from Waste (REW) Virtual Conference held in early October, Mark Reidy, a partner at Washington-based Kilpatrick Townsend & Stockton LLP, shared his firm’s experience with a large waste conversion project his firm is working on that uses a variety of government programs for financing.

The dairy cattle waste-to-bioproducts project in New Mexico is primarily producing fuel. “We stayed with transportation fuel because the RINs (Renewable Identification Numbers) and the LCFS (Low Carbon Fuel Standard) made it very compelling and [offered] a strong rate of return,” Reidy explained.

The $210 million project has 60,000 head of dairy cattle and heifers and includes eight total anaerobic digesters. The digesters are divided into four modules of two digesters each. A fifth module is a wastewater treatment facility.

“We have up to five additional projects of this size that we are going to do,” he said.

The project creates biogas, biofertilizer, aqueous ammonium, biopellets and industrial-grade water. It reduces greenhouse gases and increases available energy by 30 percent, Reidy said. “The microgrid opportunity here is not the electricity, but multiple valuable products.”

He said the management team behind the overall project, Advanced European Technology Partners, has more than 25 years of experience and more than 30 facilities throughout the world.

WEIGHING THE OPTIONS

Each of the modular AD projects could qualify for funding as a first commercial plant under the U.S. Department of Agriculture (USDA) Section 9003, according to Reidy. They also could qualify for a Department of Energy (DOE) Section 1703 Loan Guarantee, among other federal programs.

The USDA and DOE programs take about 12 months to close, however, and the team was looking for a quicker way to get funding. However, he said, the advantage of USDA option is that no fee is due until closing. Both programs, Reidy added, have a two-part application process.

When it was still considering electricity as an output, the team also looked at the USDA Rural Utility Services (RUS) program. Reidy said the program provides a U.S. Treasury loan at 12.5 basis points over the Treasury rate with no cap on senior debt. The term of the loan can be as long as 35 years or the length of the power purchase agreement (PPA), whichever is shorter.

“When we pivoted out of the electricity side, we decided to look at a couple of other programs, which were commercial programs that can go much quicker,” Reidy said. The commercial programs can be closed in six months from the application date.

The team is using a combination of the USDA Section 9007 and Business & Industry (“B&I”) loans. “It makes it a bit more complicated,” Reidy said because the project is taking $25 million for each of four modules from the 9007 program and $10 million for each of four modules from the B&I program. The wastewater treatment plant is using $10 million from the B&I program.

“As long as you keep it below $10 million on the ask, you don’t get into a very difficult scoring process,” he said of the qualification process.

After interviewing lenders, it was determined that big banks were not going to be interested, Reidy said, so the team went with a regional bank that “had an appetite for multiple loans.”

The project was up to $150 million in senior debt with four of modules receiving $25 million and $10 million loans from the USDA Section 9007 and B&I programs, respectively, and the wastewater treatment plant receiving $10 million from the B&I program. The team had to cover the remaining $60 million.

Because the modules were not producing electricity, they did not qualify for investment tax credits (ITCs) or bonus depreciation, Reidy said. He noted that Congress is considering an ITC along with the Tax Reform Act that would give 30 percent for biogas projects and 30 percent for nutrient recovery systems.

New Market Tax Credits (NMTCs) are nondilutive over time and offer a seven-year period for the provider of the money to realize its incentives.

Employment-based- (EB-)5 funding is another mechanism that can be used. “EB-5 is something we are strongly using; in fact, we are raising about $92 million in EB-5 money across not just this project but the next ones,” Reidy said.

He added that this program is nondilutive because it is structured as a loan. “It is more difficult to structure it as equity.”

Funding is invested into a project to procure visas and green cards from the U.S. Office of Immigration and Department of Treasury based upon the injection of $500,000 for 10 direct, indirect and/or induced jobs per each visa, according to Reidy’s presentation.

State and federal grants and subordinated debt also were used on the New Mexico project, he added.

“The interesting thing with subordinated debt is USDA and their new Business and Industry rule can cover that with a loan guarantee, where they couldn’t in the past,” Reidy said.

He described some of the challenges of going through this process, including dealing with a rule that was being put into place. “The new rule actually opened it up to more lenders of record. Some of the nonregulated lenders, like private equity companies, could get in on being lenders.”

The B&I program initially had a 51 percent U.S. ownership requirement that challenged the use of foreign equity from the project’s European technology partners, Reidy said, adding that the new B&I rule removed this restriction.

The B&I has a 3 percent closing fee and the 9007 program’s is 1 percent. B&I also has an annual fee of 5.5 percent, while the annual fee for the 9007 program is 0.25 percent. The projects were required to be in an area of 50,000 persons or less, which they met. They also needed to have a National Environmental Policy Act (NEPA) permit, which Reidy said could take up to eight months to obtain.

The USDA programs were attractive to the dairy industry, according to Reidy, because they eliminated the U.S. Environmental Protection Agency (EPA) groundwater penalties for manure.

FINANCE STRUCTURE

A total of 13 loans were obtained. Four were for project construction and nine were permanent loans. With the 9007 program, money is taken out along with the permanent finance. With the B&I program, the construction funding is built into the permanent finance. Both programs have 15-year loan guarantees.

The package includes full construction wrap, insurance and offtake price floors and feedstock price collars.

The projects have what Reidy described as “10 strong revenue streams”: biogas for renewable compressed natural gas and renewable liquefied natural gas; RINs; California LCFS credits; New Mexico carbon credits; New Mexico RECs; pellets; aqueous ammonium; fertilizers; compost; and New Mexico Water Recycling Credits.

“For the next projects we are looking at, there is a possibility of using a 100 percent debt credit facility that we are developing,” he said. “We have several clients in front of this right now.”

This structure requires no equity, avoiding company ownership dilution, Reidy said, and is at the project level.

“It requires an investment-grade, credit-rated product offtaker or a performance guarantee provider,” Reidy said. “The product offtaker has to do a ‘hell or high water’ provision for a minimal percentage that would cover the debt service on an annual basis.”

Another financing option is a performance bond that goes beyond the construction and after the commercial operations date (COD), through the length of the term of the loan.

“Either of these mechanisms could make this work if we could get to the first closing,” Reidy said.

He said a lot of people get “challenged with the working capita.” He talked about a new loan fund that will lend up to $10 million in nondelutive funding for up to 10 years at a flat 10 percent. “It is going to be secured by cash flowing contracts at the bottom,” Reidy explained. “It comes in at the parent level, not the project level, so it can be used as working capital, and you can also push some of it down to the project level.”

The author is editor of Waste Today and can be reached at ksmith@gie.net.

The need for and use of refuse-derived fuel (RDF) has changed over the last 30 to 40 years. Boilers once needed fuel from waste to be resized, but that became less important as mass-burn waste-to-energy (WTE) facilities proved effective without pretreatment of waste.

Today, a resurgence of refuse-derived fuel demand is being necessitated by newer waste conversion technologies, such as gasification. Also, material recovery facilities (MRFs) and mixed waste processing facilities are producing fuel for a variety of industrial processes with their residual material. These newer processes often require more sophisticated techniques than older systems to optimize the calorific value that can be captured from the fuel.

The trends and processes that are giving refuse-derived fuel more attention these days were the focus of a session at the Renewable Energy from Waste Virtual Conference in early October.

During the session, Nathiel Egosi, president of RRT Design & Construction, Melville, New York, explained that the function of a RDF plant is to take nonhomogenous municipal solid waste (MSW) and produce a high-quality fuel while removing noncombustible inorganic material, high moisture content material, and certain hazardous and recyclable items.

“RDF plants were principally developed to prepare solid waste for cocombustion with coal in a utility boiler,” Egosi said during his presentation. “Later, RDF plants with dedicated boilers were developed to achieve better economics and emissions.”

One of the first such plants was built in the city of Ames, Iowa. It came online in 1972 and still operates. The next generation of plants were built to either cocombust RDF with coal or combust RDF alone in spreader-stoker-type boilers.

Some of the first plants, like Southeastern Public Service Authority (SPSA) in Chesapeake, Virginia, and Miami-Dade County Resources Recovery Facility (RRF) in Florida, used trommels before shredding. “Trommeling was used to remove inerts before shredding to produce a low ash, high British thermal units (Btu) RDF,” Egosi said. “Trommels also were used to concentrate recyclables for recovery before production of RDF.”

Other plants used primary flail mills prior to trommeling. The last traditional plant in the U.S. was a 2,000-ton-per-day system built in Robbins, Illinois in 1995.

“RDF is really a U.S.-developed technology that is proven and [has been] in use for over 40 years,” Egosi said.

He said the difference between RDF plants of today and older plants is the consequence of three things. First, the waste stream has changed dramatically. Second, a lot of lessons have been learned and, third, “mass-burn boilers really do work, so the need to alter MSW and manipulate it in a certain way became obsolete and people moved away from RDF.”

Around 2005, however, renewed interest in RDF arose due to the rise of gasification developers. Oil prices also went up, making the economics of such plants intriguing.

The RDF needed to be produced from MSW to make it suitable for a downstream thermal process, to fire in gasifiers or nonMSW furnace/combustors/kilns and to prepare it for downstream chemical processes, Egosi said.

A number of demonstration and pilot plants were built. One in San Antonio closed due to economics. The future of a plant in Philadelphia is uncertain, and a plant in Edmonton, Alberta, is presently providing RDF to Enerkem’s waste-to-methanol plant.

Since 1985, tipping fees have held flat and the density of the waste stream has changed quite a bit, he said. Since that time, textiles have gone up, glass has gone down, food scraps had a dip in 1990-2000 and metals have remained relatively flat. Paper has gone from 31 percent of the waste stream down to 26 percent. Plastics have experienced the most dramatic change from about 3.4 percent of the waste stream in 1985 to 12 percent of the waste stream in 2017.

Engineered fuel is a term that is used when an RDF is further treated or blended with other waste types to achieve a higher and more consistent Btu value, lower moisture content and more predictable emissions, Egosi said.

MEASURING QUALITY

Brian Schellati, director of business development at Van Dyk Recycling Solutions, Stamford, Connecticut, said during his presentation that the company has completed more than 1,700 recycling projects, 250 of which are turnkey MRFs. Of those, only five have been making fuel from mixed waste. But, unlike Europe, Schellati noted, “it has mainly just been a growing market over the last couple of years. More and more processing is being done to create a fuel from mixed waste.”

The incineration or gasification of this material comes with the risk of unacceptable levels of inerts, chlorine and water content. These issues can lead to poor efficiency in gasifiers and overburn situations in kilns because of the reduced energy content from noncombustible inerts. They also can cause increased downtime in light of precipitation and buildup of salts in kilns and increased exhaust emissions. These contaminants also can cause damage from corrosion in thermal systems.

“This results in a poor thermal substitution rate, higher maintenance costs and more downtime,” Schellati said. “Therefore, it is necessary to measure and check these critical values.”

Schellati said contaminant levels currently are measured by doing spot tests. The samples are taken to a laboratory, but often, the results are not satisfactory because the spot tests are not representative of the entire material makeup and there is a high lag time before the results are available.

During his presentation, he showed an analysis of three small fuel samples taken from the same stream of material, which showed major differences in the results.

In another example, Schellati showed a comparison of results from two laboratories that varied by more than 50 percent. The solution, he said, is real-time online analysis of least 10 percent of the production stream of the fuel.

“We use near infrared sensors to identify the different materials in the fuel in real time and on a moving average,” he said.

Some of the key values of interest are chlorine content, water content and heating value of the fuel.

PVC plastic is the main material that can be recognized to measure chlorine content. The moving average over 5 minutes that is calculated is far more precise and useful than the spot results from the laboratory, Schellati said.

“In conclusion, online analysis in real time provides continuous monitoring and measurement of the entire material stream, supplies the producer and the buyer with instant data and, most importantly, ensures that the end user gets consistent product quality for optimal efficiency. It also minimizes costly maintenance and downtime,” he said.

LEARNING FROM EXPERIENCE

Jonathan Menard, executive vice president of sales and strategic positioning for Machinex Technologies, Plessisville, Quebec, said during his presentation that he is observing a change in the market in the U.S., U.K., France, Spain and Australia. Over the last eight years, the company has built more systems for the MSW and commercial and industrial (C&I) materials markets with the aim of generating RDF or SRF (solid recovered fuel) and recyclables recovery, despite usually building single-stream systems.

Menard said the difference between SRF and RDF is quality. RDF is a lower quality fuel than SRF. Its calorific value is between 10 to 20 megajoules per kilogram, and it has no particle size requirements. The moisture restriction also is vague, between 35 to 40 percent maximum. “And the main difference is, in Europe, there is no regulation regarding RDF,” he said.

The SRF calorific value is 20 megajoules per kilogram or higher. The size ranges from around an inch to an inch and a quarter. Another difference, he said, is that it is a regulated fuel.

He said Machinex has built four plants in the U.K. over the last five years that are producing RDF and SRF. The first one the company built was Veolia Warren Farm in Fareham, England. It is a 15-ton-per-hour plant processing C&I and civic and amenity (C&A) waste with the goal of recovering fines, ferrous, heavies, PVC (polyvinyl chloride) and producing a SRF product. It was Machinex’ first project dealing with SRF. Menard said the chlorine content was low at 0.4 percent because of customer requirements, and therefore, Machinex put an optical unit in the system to remove PVC.

Machinex’s second plant, completed in 2013, was Public Power Solution, Swindon, England. It is a 15-ton-per-hour SRF and RDF plant that processes municipal solid waste and C&I. The system processes a variety of materials with a high moisture content and uses a rotating drum dryer to convert RDF into dry SRF that meets European standards.

The third plant Machinex built in the U.K. was Shanks Waste Management in South Kirkby, England. It helps the surrounding area of Wakefield district achieve a 95 percent landfill diversion rate, Menard said. The 30-ton-per-hour system recovers mixed paper, plastic film, mixed plastic, ferrous and nonferrous metals and 60 millimeter fines.

The fourth plant Machinex is building in the U.K. is at Levenseat Renewable Energy Ltd, in Lenark, Scotland. It is a 42-ton-per-hour C&I and MSW plant. At the time of the REW Conference, the project was two weeks into construction but had been planned for about two years.

Levenseat uses thermal drying of fines to improve RDF generation and landfill diversion. The business model is based on a low calorific value to allow for more RDF to be burned in the gasifier. This allows for more material coming in.

Menard advocates these types of systems at the front end of a waste conversion project. He said the added value of mechanical pretreatment is first to convert more waste material into valuable commodities as an RDF and SRF, significantly increase landfill diversion and give a chance to increase recycling capture.

“What we learned through all these projects is that it is one thing to generate an SRF and RDF, and it is much more difficult to generate a homogeneous one,” Menard said. “And this is what all these advanced thermal plants require because they don’t have to keep compensating on their side, so you try to deliver something homogenous. That is the key to success.”

The author is editor of Waste Today and can be reached at ksmith@gie.net.