December 2024 - MABA Biosolids Spotlight
Provided to MABA members by Bill Toffey, Effluential Synergies, LLC
SPOTLIGHT on Updates for 2024
2024 has felt like a year of looming transitions. In the political realm in the United States, this certainly is true. In the world of biosolids, this is particularly true with PFAS. EPA’s assessment of biosolids-borne PFAS is awaited, with no small amount of trepidation, with state-sponsored surveys of biosolids generators in Maryland and New York, and with research into biosolids-borne PFAS pathways, notably Dr. Ian Pepper. But we also have transitions in the forms of retirements and job changes. Greg Kester is retiring from CASA, the California counterpart to MABA, and his position is being filled by Maile Lono-Batura, signaling the need at WEF to fill the position of national biosolids lead. Big projects are nearing completion, enabling agencies to transition to Class A levels of pathogen reduction, none bigger than the WSSC Water’s Piscataway Bioenergy Plant. Several thermal destruction projects were underway in 2024 and awaiting completion in 2025 which may also fundamentally expand technology options in the region. If 2024 is a year of transition, then 2025 may naturally become the year of conclusions.
All MABA SPOTLIGHTS in 2024 have acknowledged strong efforts by teams of biosolids practitioners to “make things work well” with biosolids. No SPOTLIGHT is more compelling than that of Bloom, the DC Water soil product marketed by Blue Drop. It demonstrates the perseverance of a strong vision, one that combines a great product that “sells itself” and meets the test of consumer preferences, with that of a sound story of resource recovery and a circular economy, genuinely and uniquely serving the farm and garden community. The September 2024 SPOTLIGHT describes the important public works, golf courses and recreational facilities for which Bloom supplies nutrients and organic matter. In 2024, yet more new golf courses, landscape companies and farms were added to their growing roster of customers. For agricultural outlets of Bloom, the summer drought underscored the economic and environmental benefits of Bloom over commercial fertilizers. In 2025, DC Water and Blue Drop look forward to the completion of a paved, covered curing pad that will provide increased storage and production capacity for Bloom’s value-added customers.
DC Water’s strong vision inspired the region’s largest new biosolids project of 2024, the WSSC Water Piscataway Bioenergy Plant. This new plant was explored in detail in the November 2024 SPOTLIGHT, as the ribbon cutting on October 30th marked the near full operation of this transformational solids system. This transformation included an interlinked transportation system for the agency’s six plants, the centralized thermal hydrolysis of solids, digestion of treated solids through new mesophilic digesters, treatment of biogas for energy capture, and production of a Class A dewatered biosolids product. The project was managed through a special contract system that brought it to completion on schedule and on budget even during the disruption of the global pandemic.

The Cambi Thermal Hydrolysis Process, with its reactors at WSSC Water shown here, is a key component of solids treatment for both DC Water Blue Plains Advanced WWTP and for WSSC Water’s Piscataway Bioenergy Project for achieving through mesophilic digestion a high degree of volatile solids destruction, superior biogas production and low odor biosolids cake.
While WSSC Water is at one end of the scale of transformations, the Borough of Quakertown’s project, reported in the February 2024 SPOTLIGHT, is at the other end, but for this Pennsylvania community, no less transformational. Using the proprietary high-solids digester technology of the Anaergia company, Quakertown has new digesters under construction and has prepared for the biogas fueled generators and its high strength organic waste receiving station, as it moves toward energy self-sufficiency. Much of this work is expected to be completed in 2025.
Though not a focus of a SPOTLIGHT in 2024, a project similar to Quakertown’s is underway at State College, Pennsylvania. Having reached the life expectancy of an enclosed biosolids composting facility, which for its time was a groundbreaking Class A treatment facility, the University Area Joint Authority embarked on a project to optimize energy and resource recovery, with a focus on digestion and biogas. As reported in the local newspaper (An $81M project underway at UAJA will turn waste into renewable energy. Here’s how), this is a $81 million replacement to the compost plant. The project for UAJA has been led by Jason Wert, of Rettew Engineers, a MABA member who has participated in MABA programs in which his client Tom Darby of the Hermitage Food Waste to Energy Facility was featured. A key partner in supplying equipment to UAJA has been Veolia Water Technologies & Solutions, also a MABA member, which offers its proprietary Monsal 55 digester system, featuring thermophilic batch tanks. The Monsal tanks will separately digest to Class A standards the wastewater solids and trucked-in food waste, but the two digestates will be blended together. The biogas off of the digesters will be cleaned up for pipeline injection as a renewable natural gas. The blended digestate will be sent to Veolia belt dryers for a second point of Class A pathogen compliance, and the resulting product is expected to be low odor and suitable for commercial uses.
Few public utilities in the United States can claim the integration of energy and resource recovery better than that achieved by Rahway Valley Sewerage Authority (RVSA). As explained in the October 2024 SPOTLIGHT, RVSA’s digesters produce biogas, the gas drives electric generators, waste heat from generators dries biosolids into recyclable products, and food waste supplements the digesters to produce more gas for plant electricity. To this equation will be added in 2025 an agreement hammered out in 2024 to have Waste Management, the current supplier of the food waste, install, own and operate a gas clean up system that will produce a Renewable Natural Gas (RNG) meeting pipeline injection standards. The value of RNG is substantially higher than the natural gas needed to power the generators, so RVSA has a financial gain with this relationship.

Rahway Valley Sewerage Authority is a leader in the Mid-Atlantic region in implementing a vision of deploying capacity in its anaerobic digesters to accept supplemental high strength organic waste, as shown in this picture of the receiving station for Waste Management’s “engineered bioslurry,” for the enhanced production of renewable natural gas planned by RVSA for pipeline injection.
The MABA SPOTLIGHT for 2024 has shown its light on some important expansions within the region in biosolids “productification” capacities. This is the evolution of solids treatment systems to produce materials that meet the Class A pathogen standard and that are suited for professional and consumer use in landscapes and gardens. This evolution includes two large regional composting plants, featured in the April 2024 SPOTLIGHT. Both were completed in mid-2024 and both are located adjoining municipal solid waste landfills. One was built by McGill Compost in Fairless Hills, Pennsylvania (McGill Fairless Hills), and the other by Synagro, in Cumberland County, New Jersey (Cumberland County Organics Recycling Facility). Both facilities enter 2025 very nearly at full operating capacity, and both are deploying composting systems that, while drawing on well-known principles and practices, inevitably require tweaking for best performance. Both facilities accept biosolids from multiple public agencies. Both facilities have begun shipments of compost and are preparing for their first Spring market, and together they will more than double the volume of biosolids compost currently in production in the mid-Atlantic region. Tom Herlihy of Synagro is particularly proud that the compost produced in Cumberland, using the turned aerated pile composting system, has been achieving very high scores on the US Composting Council’s Seal of Testing Assurance measures for germination and seedling vigor, which Tom believes is the single most important “bioassay” for compost. And while many biosolids practitioners have been sitting back, waiting for words from EPA on the future of regulations of PFAS contaminants, neither compost plant has seen PFAS become an issue for its biosolids suppliers or for its compost customers.

Biofiltration of indoor air is a key aspect of commercial scale biosolids composting process, this picture illustrates the scale of the biofilter at Synagro’s Cumberland County Organics Recycling Facility.
The July 2024 SPOTLIGHT featured emerging thermal conversion technologies – EarthCare Solutions, Bioforcetech, Ecoremedy and CHAR Technologies.
The merchant gasifier facility installed by EarthCare Solutions in Bethel, Pennsylvania, is the furthest along of the thermal projects in the mid-Atlantic region. It has two process gasifier trains, one devoted to poultry manure and the other to biosolids. Both lines have been in full operation, though both also are occasionally held offline so that improvements can be made. Sean Sweeney, director of operations, explains that the biosolids gasification system is being upgraded to better handle fine particles, reducing the proportion that are captured in air pollution control equipment and enabling their reintroduction to the gasifier itself. EarthCare is also modifying the receiving area for quicker unloading of trucks, including a higher speed belt and a longer conveyor reach for higher stacking.

Of the five thermal facilities under construction in the Mid-Atlantic region, the Earthcare Solutions facility in Bethel, Pennsylvania, is the closest to full operation, with the two gasifier trains shown in this photograph, one for poultry litter and the other dedicated to biosolids cake.
Bioforcetech has been working at the Ephrata Borough treatment plant to bring its Pyreg pyrolysis unit into full performance. Ephrata expects that in first quarter 2025 commissioning can begin, so heat coming off the pyrolyzer can replace the temporary use of propane for the drying of the solids ahead of gasification.
Two other thermal units continue to be pursued, the CHAR Technologies mobile unit by Synagro and the Ecoremedy gasifier by the Derry Township Municipal Authority. This latter facility met a milestone with the signing of contracts in November for construction of the gasifier and related equipment. Maryland regulators have the CHAR unit in front of its permit writers, and Synagro expects approval in 2025.
To these four thermal processes in the region can be added a fifth project, the Aries Kearny Biosolids Processing Facility. For a few years now, Aries Clean Technologies has worked to iron out problems with this facility, which is designed to daily gasify over 400 tons of biosolids cake for disposal, with the ash used as a concrete additive. According to an October 3 press release, the facility has now achieved “integrated processing.” An operator at the Linden-Roselle Sewerage Authority says that Aries is still in “shake down,” and has not yet sought any biosolids for processing.
The January 2024 SPOTLIGHT on BaltimoreDepartment of Public Works’s biosolids operations featured plans to turn around conditions that had threatened regulatory and permit compliance by the city at both the Patapsco and Back River plants. As 2025 approaches, elements are in place for the turn around: Jacobs Solutions was contracted to handle the solids side of treatment, and major repairs are underway on the Egg-Shaped Digesters. While dryers located at each of the two plants are not operating, their owner, Synagro, is taking the contractually required solids for disposal. Biosolids that are dewatered by Jacob at Back River are delivered to Veolia for composting, an element of the original biosolids plan that has performed throughout the troubles. To provide a long-range solution, Dr. Mahmudul Hasan, Chief Technology Officer, has led the issuance in November 2024 of a Request for Proposals, due in 2025, to provide Baltimore with a comprehensive DBFOM biosolids project (design-build-finance-operate-maintain) for a “best-in-class solution.”

Baltimore City Composting Facility has been operating through the changes underway to solids processing at the Back River plant, and is now receiving its dewatered cake from Jacobs, the contractor for the city managing the solids treatment systems.
The May 2024 SPOTLIGHT featured sludge incinerators.DELCORA in Chester, Pennsylvania, has the largest incinerator operation, with twin Multiple Hearth Incinerators (MHIs) handling 20,000 dry metric tons of solids annually (DMT/a). The Atlantic County Utilities Authority (ACUA)incinerates 10,000 DMT/a and operates the region’s fourth largest set. Both facilities serve as regional sludge disposal centers, and both have been modified in recent years to meet national standards for Sewage Sludge Incinerators (SSI). Nevertheless, the search for improvements is constant. For DELCORA’s Mike Disantis, the challenge has been dealing with cyanide formation in the incinerators, which can give rise to compliance issues on the liquid side. To fix this problem, the agency is installing an afterburner to destroy the compounds that can form cyanide. At ACUA, Joe Pantalone has been sorting through options for improved reliability and fuel efficiencies, setting up some straightforward replacements of induction fans on the scrubbers and looking to make consistent the moisture content of the sludge feedstock, by improving dewatering and blending of outside cakes. Disantis and Pantalone are both watching the unfolding issue with PFAS, as incineration is regarded as a potential technology for destroying biosolids-borne PFAS, yet neither manager expects to be on a leading edge of studying stack emissions for PFAS, at least until a federally approved test method is available.

DELCORA operates the largest set of sewage sludge incinerators in the Mid-Atlantic region, with its multiple hearth incinerators processing 20,000 dry metric tons of sludges annually; installation of afterburners is planned in 2025 to reduce cyanide formation.
If the September SPOTLIGHT on Bloom discusses one of the finest examples of a program for Class A biosolids, then the June 2024 SPOTLIGHT feature of Henrico County, Virginia, is one of the finest examples of a program for a Class B biosolids. The Henrico process and program were the subject of a tour for attendees of the MABA Summer Symposium. Division Director James Grandstaff, Henrico Department of Public Utilities Water Reclamation Facility (WRF), stands by his biosolids program for meeting today’s goals, which include a focus on serving his nearby agricultural community, while looking well into the future.

Henrico County’s Water Reclamation Plant produces a Class B biosolids cake supplied by Synagro to a loyal roster of farmers in eastern Virginia who benefit from the close attention by Henrico’s plant operators to high biosolids quality.
The many agencies and companies that MABA SPOTLIGHTs presented in 2024 have in common the story of how diligence and perseverance are hallmarks of success in accomplishing cost effective, sustainable and environmentally beneficial biosolids management. 2025 will be a great year for biosolids in the Mid-Atlantic region.
For more information, contact Mary Baker at [email protected] or 845-901-7905. |