RFPs due in June for biogas plant
Grand Rapids and Wyoming want proposals for a facility to turn sewage sludge into energy.
Representatives of the cities of Grand Rapids and Wyoming, through their Grand Valley Regional Biosolids Authority, will spend this summer studying proposals due in June from companies interested in building a biodigester plant that can turn municipal sewage sludge into methane gas.
Last year the GVRBA reviewed companies that indicated an interest in the project and pre-qualified five primary firms: Anaegia, Chevron Energy Solutions, Fleis & Vandenbrink Engineering, Swedish Biogas International, and United Water Environmental Services/Kohlberg Kravis Roberts. Four of the primary companies indicated they would partner with local firms if they won the contract. Fleis & Vandenbrink is a West Michigan company.
In its introduction to the RFP issued in January, the GVRBA said it “prefers that proposals be based on a design/build/own/operate/finance approach; however, other financing, ownership and operating approaches that are consistent with the GVRBA’s goals and Vision 2020 may be considered.”
The successful proposal would entail a service agreement covering a minimum of 20 years, with two five-year renewal options after 20 years.
The RFP also states the long-term program should, at a minimum, reduce GVRBA’s total costs, provide diversity and reliability in the use of the solids, and beneficially use the solids. The proposers are encouraged to meet the goals of the GVRBA’s Vision 2020, which will serve as the basis for the evaluation of proposals.
Vision 2020 is a “sustainability framework” for the GVRBA, which can be viewed online at gvrba.org.
The Grand Valley Regional Biosolids Authority is an independent governmental entity that represents a partnership between Grand Rapids and Wyoming. It was launched in 2003 to share the cost of processing sewage sludge and recycling it, when possible.
Sewage sludge is now commonly called biosolids.
The partnership was formed when both communities realized it would be more cost effective to share one large facility.
In 2009, the GVRBA dedicated a new 3.5 mile pipeline from the Wyoming to the Grand Rapids treatment plant, where GVRBA had spent $35 million on a new "dewatering" facility that uses centrifuges to remove the water from the biosolids, much like the spin cycle in a washing machine.
Aaron Vis, project manager at GVRBA, said the authority processes about 50,000 wet tons a year in its dewatering plant. That leaves it with 18,000 dry tons; of that, about 4,200 is applied to farm land and the remainder goes to two West Michigan landfills, where it is, in effect, “recycled” because it enhances production of methane. The landfill companies capture and sell the methane or use it to generate electricity.
There is a cost for disposing of the biosolids in landfills, however, although Vis did not know what it was.
Myron Erickson, superintendent of the Wyoming Clean Water Plant — its wastewater treatment plant — said the RFP does not require the biosolids plant to be an anaerobic digestion process, but he expects it will probably be anaerobic.
The process breaks down biosolids to methane gas, which is then captured and used either as heating fuel or to run generators that produce electricity.
When asked the estimated cost of a biogas plant large enough to dispose of all the GVRBA biosolids, Vis said he did not know because it would depend on what is proposed, noting that the RFP is “pretty wide open” without a lot of design specifications.
“If I had to guess, I would say probably in the $30 (million) to $40 million range, but it’s really up to them — how and what they propose and where they want it.”
The RFP does suggest a couple of possible sites for the biogas plant: One is adjacent to the dewatering plant near the Grand Rapids wastewater treatment plant on Market Avenue; and another is the Wyoming Clean Water Plant.
“We haven’t really told the proposers where they have to build,” said Vis. “The neat thing about the RFP is that if they want to propose something else that’s better for both our interests, then they have the ability to do that.”
“We letting the creative forces of the biosolids market design it,” he added.