A New Jersey utility uses a National Biosolids Partnership management program as a path to greater efficiency and performance in its incineration plant.
At the Atlantic County (New Jersey) Utilities Authority, where efficient biosolids incinerators have a major impact on operations, leaders decided in 2010 to hold their own feet to the fire by enrolling in the National Biosolids Partnership management system certification program.
Joe Pantalone, who joined ACUA in 2013 as vice president of the wastewater division, says employees rose to the challenge as the clean-water plant serving the Atlantic City region rose through the four levels of certification: Bronze in April 2012, Silver in January 2013, Gold in August 2013 and Platinum in November 2014.
The team is proud of the certification plaques that hang on the walls, but more important are reports showing that the only biosolids incineration plant to seek NBP certification has recorded significant improvements in operations.
Key documents produced by the team include annual reports and a Biosolids Management Program Manual, a detailed booklet that outlines goals, objectives, best management practices and the parties responsible for them. Chris Harris, operations director, oversees the updates to the manual as the team identifies new goals or makes other adjustments. To complete each step of certification, the team’s reports had to demonstrate that ACUA met the NBP program criteria. Their conclusions needed the affirmation of an outside auditor.
Eyes on the future
When the division entered the NBP program, the implementation team included Harris; Tom Lauletta, division vice president; Bob Carlson, assistant operations director; Katie Vesey, deputy chief finance officer/director of research and development; Greg Seher, project manager; and others. Pantalone has since replaced Lauletta.
Originally, Lauletta and the team wanted to use the program to prepare for a wave of retirements among senior operators who were most experienced with the incineration system. The authority’s regional complete mix activated sludge plant lies on 60 acres on an island at the edge of Atlantic City.
“We had a lot of retirements in our system, and we were looking for a model for planning for the future,” says Harris. As it turned out, the retirements were more ripple than wave, as one or two experienced operators left per year. But Pantalone says that has not diminished the value of the NBP program: “We’re a 24/7 operation. On each shift we had operators with specific areas of expertise, but we didn’t necessarily have the depth of expertise on each team.”
Class 3 operators were well equipped to operate the incinerators, but less experienced operators were not fully prepared for that job, the most challenging in the ACUA treatment process. Thanks to the focus on NBP certification, “we’ve been able to get some of the newer staff up to the Class 2 and Class 3 operator levels,” Harris says.
Mentorship by senior operators was important, Harris says, because operators have to make judgment calls on how to handle biosolids entering the incinerators. Experienced operators were able to communicate the subjective process while training newer operators.
Even that training was improved as ACUA moved up the certification ladder. Thanks to audits, Carlson determined that different shifts and different operators produced varying results in incineration efficiency, partly due to differences in operating styles. “Bob was very much in tune to measuring the proficiencies of the people moving through the training program,” says Pantalone. Carlson used data collected from the system process controls to track 10 metrics of biosolids handling proficiency. He used charts to show employees and the managers the individual results areas, including:
- Auxiliary fuel usage per wet and dry ton
- Average exhaust stack percent oxygen
- Average solids feed rates per wet and dry ton
- Average percent total solids from the centrifuges
- Downtime as a percentage of runtime
- Afterburner temperatures
Because of the variances Carlson found from shift to shift and operator to operator, ACUA brought in an outside expert to supplement the internal training program and recommend ways to achieve consistently excellent performance. Mike Hilton, technical director for incinerator maintenance contractor Industrial Furnace Company, taught classes and offered hands-on training to help operators bring the incinerators to peak efficiency.
Jonathan Clayton, a Class 2 operator being groomed for more responsibility, says having Hilton advanced his learning curve because he did more than just lecture. He worked with the operators inside the plant, offering advice and explaining why new steps would improve their proficiency: “He goes over every change we’re making and we’re going to make so we understand why they are important.”
The NBP certification program helped team members achieve a variety of operational goals by requiring them to assess operations, review outside audits and commit to best management practice plans at each step of certification. Harris says the NBP program focused leadership on defining the elements of best management practices and then tracking key results, “to make sure we were working toward goals and objectives.”
The fact that ACUA reached Platinum certification ahead of schedule last fall does not mean the work is over. “It’s a perpetual program,” says Harris, who has a lead role in tracking progress on best management practices. “Platinum certification means that we meet the criteria and that we practice what we preach.” But reviews and audits of the best management practices will continue, and it is up to the utility to maintain its path to greater proficiency.
Pantalone says the certification program helps people keep their eyes on the bigger picture: “You can get buried in the emergencies of the day, but because of the regimen of the program, there are milestones you must meet. It’s a self-reliant and self-demanding process.”
According to Carlson, better-trained furnace operators benefit ACUA in two ways: by making the day-to-day process more efficient and thus requiring less energy to turn biosolids to inert ash, and by reducing the need for maintenance shutdowns.
Federal standards require biosolids incinerators operate at a minimum of 1,500 degrees F. Harris and Carlson say that keeping temperatures at or above that mark helps save on the cost of running the dual-fuel incinerators, which burn natural gas with diesel fuel as a backup. The incinerators have been operating nearly 1,600 degrees on average, and the first goal is to get that down to 1,575 degrees — then 1,550, and then 1,525.
“Temperature control also has a lot to do with the maintenance at the incinerators,” Carlson says. “We used to shut down four times a year for maintenance. Now, because of better controls in the process, we are down to two times a year.”
The plant’s newer Incinerator B (Combustion Systems) has an hourly maximum feed rate of 5,798 dry pounds per hour and a daily capacity of 56.4 dry tons per day. It is usually out of service from 10 to 14 days during a maintenance shutdown. When that happens, ACUA’s first option is to activate its older Incinerator A (Envirotech, hourly maximum feed rate 2,446 dry pounds per hour, daily capacity of 25.5 dry tons per day).
A second option if the smaller incinerator can’t keep up with the load is to store excess biosolids until the main incinerator is back online. The final option is to haul biosolids to another facility for incineration.
At present, the incineration plant has excess capacity: The volume of biosolids trucked in by smaller municipalities under contract has declined. That’s an added incentive to make operations more efficient.
Squeezing out savings
Beyond the incinerator, ACUA’s best management practices plans have focused on maximizing the solids content of material coming from the facility’s G2-120 dewatering centrifuges (Alfa Laval), each with a capacity of 300 gpm at 5 percent total solids, installed in 2006. Cake was running at 22 to 24 percent solids before ACUA entered the NBP program but now averages 26 to 28 percent.
The plant neared its original goal of 30 percent several years ago. “We may have taken a little bit of a slide while getting our newer operators up to speed,” Harris says, although he believes 30 percent on average is still achievable. Carlson says ACUA will seek ways to exceed 30 percent: “Until you reach about 40 percent, our incinerator could operate more efficiently.”
ACUA is also holding customers to higher standards. “That is a very strong paragraph in our contracts,” Pantalone says. New contract language requires outside sources of material to meet a standard of 16 percent solids. Material that falls below that standard could be turned away or subjected to a surcharge.
A key goal set forth in the 2014 implementation committee report was to design a project to bring the site into compliance with new federal regulations on fugitive ash. A performance review has shown that the facility can meet other new state and federal standards that will take effect in 2016. The team also plans to revisit potential for using heat from the incineration process to generate more electric power on site.
An original goal of the NBP program was to reduce the energy used to incinerate biosolids by nearly a third, but that meant increasing the feedstock total solids to 30 percent or better. The energy savings goal is still in place, but the target date has been delayed. It’s a safe bet the ACUA team, guided by the management plan, will pursue that goal with tenacity.