The City of Lockport is considering adding new technology to its wastewater treatment plant that would dry sludge into compost and replace the city's current composting facility.
The technology, simply named sludge driers, can reduce the water content of the sludge so that it contains 90 percent or more biosolids, far beyond more conventional methods. A belt press can squeeze the sludge until it's about 20 to 25 percent solids, while a solid bowl centrifuge can produce 25 to 30 percent solids.
The end result of sludge drying is solid enough that wood-chips do not need to be added to produce compost.
Sludge is a byproduct of wastewater treatment that is, essentially, treated human excrement.
The Lockport Common Council voted Wednesday to hire Nussbaumer & Clarke, Inc. to conduct a cost-to-benefit analysis on installing the technology for a fee of $26,500.
The resolution notes the city's compost facility is near the end of its designed service life.
"Given the age of the compost facility, we figure now is a good time. There is going to be a capital investment one way or another," said Michael Marino, chief executive office of Nussbaumer & Clarke.
Marino said it's much too early to estimate the total cost of purchasing and installing, manning and powering the technology. However, some sludge driers are able to recycle the heat they generate and reuse it as power.
And, the city may be able to apply for grant funding through the state's Water Quality Improvement Program to help fund the project.
While compost is provided to residents for free — though there is a loading fee of $10 to $20 per cubic yard — Alderman-At-Large Joseph O'Shaughnessy suggested the city could sell it to nearby golf courses for a profit.
Marino said the technology might even be more environmentally-friendly than the city's current composting process, as it eliminates the need to truck sludge from the plant to the compost facility.
"This might have a smaller carbon footprint," said Marino, though adding he would not know for certain until they complete the analysis.
The analysis will take several months, Marino added.