MSW and Biosolids Become Feedstocks for Ethanol

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Courtesy of BioCycle Magazine

The first commercial facility designed to recover recyclables from municipal solid waste, and utilize the residuals with biosolids as feedstock for ethanol production, is moving forward in Middletown, New York. The Orange Recycling and Ethanol Production Facility, to be built on a 22-acre site adjacent to the Middletown Wastewater Treatment Plant, has capacity to process approximately 230,000 tons/year of MSW and 49,000 dry tons/year of biosolids. City owned land will be used for the project.


The facility, expected to start operating in 2001, will cost over $150 million and employ up to 200 workers. The front-end of the plant will house a tipping floor and MRF with two sorting lines — one for separated recyclables and the other for mixed waste. RRT Design & Construction of Melville, New York is supplying the MRF equipment. Masada Resource Group, based in Birmingham, Alabama, is providing the ethanol technology and will manage the construction and operation of the facility. Its CES OxyNol™ process, developed by Masada, the Tennessee Valley Authority (TVA) and Mississippi State University (a research partner), converts the cellulose present in MSW to fuel alcohol (specifically ethanol). Stone & Webster Canada Limited is involved in construction of the ethanol production plant. The project will be financed through equity secured by Masada and municipal bonds.


To get the waste flow necessary to make the plant viable, Middletown invited all the other municipalities in Orange County to participate in the project. Disposal contracts will have a minimum of 20-year terms through the City of Middletown. “Middletown holds the long-term contracts,” says Al Fusco, Commissioner of Public Works. “They will provide investors with a level of comfort.” The communities will be responsible for collecting and hauling their refuse and recyclables. Those contracting with the city will pay $65/ton, the current rate of local tipping fees. The contracts allow for annual price adjustments at a rate lower than inflation, which is currently about three percent. Over the last several years, landfill rates in the area rose at an annual rate of about seven percent. However, market pressures on regional landfill capacity and prices are likely to increase because of the impending closure of New York City’s Fresh Kills landfill.


Quantity requirements will be built into the contracts. “There are minimum amounts that the municipalities have to guarantee coming in, while the maximum amounts are fluid,” Fusco explains. “We’re taking a basket approach to the contracts. If one municipality is under and one is over, we believe it will even out so Middletown can meet its put-or-pay obligation to Masada. On the other end, the communities will save money in two ways. First, because residents will have all of their waste collected at once, it will cut down on collection fees. And then, because of the terms of the contracts, the prices will be stabilized.” So far, 21 of the 40 municipalities in Orange County that Masada has approached have committed to disposal contracts.


The MRF/ethanol plant grew out of the city of Middletown’s search — initiated eight years ago — for a more efficient waste disposal plan. “We evaluated just about everything, including MSW composting, blue bag recycling programs, sludge composting and more,” says Fusco. “We were looking for an option that involved a tremendous amount of recycling. When we issued an RFP, Masada came forward with this approach.”


Environmental Scrutiny


One of Fusco’s initial steps was to contact Orange Environment — “an aggressive local watchdog group,” he notes — to evaluate Masada’s proposal. “When Middletown began to look at solutions, they came to us because they wanted to settle on a plan that was agreeable to environmentalists in the county,” recalls Harry Ross, who has been with Orange Environment for ten years. Middletown had good reason to seek the approval of Orange Environment. The environmental group had waged a long and costly court battle with Orange County, challenging the county’s plan to open a new $52 million landfill built on a wetland. Middletown officials realized early on that they would have to consider alternatives to relying on the county-owned landfill for disposal. (Orange Environment’s suit with the county was recently settled, with the county agreeing not to open the landfill.)


“On the new project, Middletown asked us to look at the proposal as it developed,” Ross notes. “One of the first things we did was request an independent, third-party consultant.” With Middletown agreeing to cover the costs, Orange Environment picked the Institute for Local Self-Reliance (ILSR) in Washington, D.C., which has long been involved both in recycling and biobased fuels.
 
 A representative from ILSR accompanied Fusco, Ross and other local environmental advocates to a cellulose-to-ethanol demonstration facility in Muscle Shoals, Alabama that has been operated by Masada (the only operating plant) since 1993 and owned by the Tennessee Valley Authority (TVA). It has the capacity to process about 200 tons/day of MSW and sludge.

Masada and the TVA have a research agreement to conduct testing programs at the plant and set engineering design parameters on critical unit operations. Commercial-scale equipment supplied by vendors has been installed and evaluated during the testing programs, and 32 cellulosic feedstocks and sludges from various generators have been tested.
In addition to the visit by Middletown representatives, biosolids samples from the city’s wastewater treatment plant were sent to Muscle Shoals and run through the facility. “Our consultants felt the proposal was viable,” Fusco explains. Masada was selected by Middletown as the preferred vendor in 1996.


The next step was to build overall public acceptance. “We’ve been involved with the project for four years,” says Daryl Harms, chairman and CEO of Masada. “One of the real keys is to educate the local opinion leaders and the general public about what we do.” The company and the Middletown Department of Public Works held a series of public meetings to explain what would be happening at the proposed facility. “We broke it down to the very common elements because the idea of a clean-burning fuel coming from garbage is difficult to conceptualize,” Harms recalls.


Having earned Orange Environment as an ally has made the public acceptance task easier. “When an issue comes up, we move to ensure public participation,” Ross says. “We have had a closer working relationship with Masada than we usually enjoy. For instance, they made sure we had our own copy of the documentation so we didn’t have to rely on the public library’s hours. They didn’t try to hide anything and have been more forthcoming than anyone we’ve ever dealt with.”

 

Building on Current Program


Middletown’s curbside recycling program collects mixed recyclable containers on the first and third Fridays of every month and newspaper on the second and fourth Fridays. The city also has a drop-off site. Yard trimmings are picked up between April and November and transported to private composters as Middletown does not have its own composting operation. Biosolids currently are hauled to disposal sites in West Virginia.


The recycling rate, Fusco notes, is close to 20 percent. “With Masada, we can reach 90 percent-plus,” he adds. When the switch is made to the new process, plans are to use blue bags to collect recyclables. “That way, we can pick up the trash, yard trimmings and blue bags all at one time.”


At the new plant, nonhazardous MSW will be unloaded onto an enclosed tipping floor. The tipping area includes a transfer station component. In the MRF area, curbside recyclables will be placed on one separating line and the remaining materials placed on another. “The processing area will have conveyors, trommels, bag openers and a shredder,” says Nathiel Egosi, president of RRT. “We’re trying to maximize the automation. Metal, glass and plastics will be separated manually and mechanically.” Adds Fusco: “We expect there still will be a lot of recyclables in the trash bags, plus if a bag breaks during cocollection, we will be able to recover the recyclables there.”


The third area in that building will house a rotary steam dryer. Food and paper products will be dried, shredded and fed — along with the biosolids — into the ethanol production process. During that process, cellulose is broken down into simple sugars (primarily glucose) and then fermented to produce alcohol, which is distilled to market-grade purity before blending to ethanol. The four steps in the process are: Acid hydrolysis — sulfuric acid breaks down cellulose into a slurry of sugar water and acid, while lignin solids are recovered for their energy value; Acid recovery — separates the sugar and acid, which is recovered, reconcentrated and reused; Fermentation — converts the sugar into alcohol through the action of yeast; and Distillation — separates the alcohol from the liquid stillage and blends it into pure market-grade ethanol. The liquid stillage is sent to an on-site pretreatment facility where methane and carbon dioxide are captured and used in the process. The plant will have the capacity to produce 7.1 million gallons/year of ethanol. The primary use of ethanol is as a component in reformulated gasoline. Most of the ethanol produced at the plant will be used in the Northeast.


Middletown is in the permitting phase for the facility. An application is being processed by the New York State Department of Environmental Conservation. If all goes according to plan, construction should begin in the fall of 1999. By Kevin Gray

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