Commercial methane digester being built in Fremont

July 7, 2011
| By Pete Daly |
Text Size:

About six years ago, according to Rob Zeldenrust, Gerber Products Co. in Fremont first proposed the construction of an anaerobic digester to turn food processing waste into methane gas that could then be fuel for generating electricity.

"They were trying to be proactive" in a way that embraces environmental stewardship, said Rob Zeldenrust, a senior manager at North Central Cooperative, which is based in Indiana but now has a branch in Fremont that was previously the Fremont Cooperative.

Last week, the ceremonial shovels finally turned the first dirt for the Fremont Industrial Park at the site of the $22 million Fremont Community Digester, which is expected to go on-line next summer, converting about 100,000 tons of waste per year to gas, fertilizer and compost. The gas will fuel a power plant generating up to three megawatts at peak production, with the electricity being purchased by Consumers Energy and added to the electrical grid.

About 15 food processing companies in West Michigan will pay to have their waste disposed of at the FCD, and Gerber is the first customer, said Zeldenrust.

North Central is a minority owner of the FCD and will market the fertilizer and compost that is a byproduct of anaerobic digestion of organic matter.

NOVI Energy, of Novi, is developing and managing the biodigester.

The FCD's majority owner is INDUS Energy LLC, an investment group based in Bingham Farms in southeast Michigan. Comerica Bank is providing debt financing for the project with the backing of a $12.8 million loan guarantee awarded by the U.S. Department of Agriculture Rural Development, under its 9003 Biorefinery Assistance Program.

Since this is one of the first large-scale anaerobic digesters using co-digestion to be built in the United States, there were 150 or more people at the ground-breaking last week. The crowd included federal, state and local government officials plus representatives of the various companies involved, including DeMaria Building Co. of Detroit, the general contractor.

"You're going to hear some people say this isn't the first," said Zeldenrust, "but all the rest of them take (waste material) primarily from livestock operations."

The FCD will process "a very small percentage of animal waste … at the beginning," said Zeldenrust. If and when the supply of waste from food processing stabilizes, that will be the main "fuel" for making methane, he added.

U.S. Sen. Debbie Stabenow, D-Michigan, chair of the Senate agriculture committee, wielded a shovel along with State Rep. Jon Bumstead, R-Newaygo, USDA State Director James Turner, INDUS Energy representative Arvin Shah, Zeldenrust of North Central, and NOVI Energy President Anand Gangadharan.

"Fremont Community Digester is demonstrating firsthand the important role West Michigan agriculture plays in developing new clean energy alternatives, which will create new jobs and protect our environment," said Stabenow.

"This project is a prime example of how agriculture, business and the community can come together to create jobs, improve the environment, and manufacture green electricity for decades to come," said Gangadharan.

According to the USDA Rural Development, the Fremont project will be one of the first commercial-scale anaerobic digesters in the United States and will reduce landfill use and improve the quality of agricultural runoff. The Fremont plant process is called "co-digestion" because it can use more than one type of organic material simultaneously — in this case, food processing waste along with a small amount of farm animal waste.

In addition to fertilizer, the solid byproducts can be used as compost to improve agricultural and garden soil and also as dried bedding for dairy cows.

Zeldenrust said the proprietary equipment for the anaerobic digester will be provided by a Danish company, which has been building this type of equipment for years. The captured methane will be piped to a pair of 24-cylinder internal combustion reciprocating engines, similar to diesel engines, which will be directly connected to the generators.

Environmental laws and the amount of waste generated at the larger food processing companies in West Michigan make their disposal of the waste a "huge problem," according to Zeldenrust.

"Fifteen different companies are under contract" to bring their waste to the FCD, he said. Food processing waste affords "maximum gas yield," more so than animal manure alone, he added.

Methane digesters have been used for thousands of years, according to Zeldenrust. He said the famous Roman baths were heated by burning captured methane from waste.

"On a volume basis, probably the biggest customer we are going to have (disposing of waste) is Peterson Farms," Zeldenrust said of the facility in Shelby.

Peterson Farms Inc. was organized in 1984 to process tart cherries from the Petersons' own farm, but quickly began processing other farmers' cherries, too. In 2004, Peterson Farms Fresh Inc. was established as a state-of-the-art, fresh-cut fruit processor, and today it is one of the largest processors of apples, grapes and oranges in the United States. The corporation markets 125 million pounds of frozen fruits and asparagus annually, along with 5 million gallons of apple juice/cider and juice concentrates. One of Peterson Farms' corporate customers is the McDonald's fast food chain, which Peterson supplies with apples.

The FCD is designed to process an average of 400 tons of waste material per day, but Zeldenrust said the region bordered by Grand Rapids and Muskegon on the south and Ludington and Reed City on the north typically generates about 4,000 tons of food processing waste each day.

The North Central Cooperative — and the Fremont Co-op, even before it became part of the larger organization — has always been in the business of selling fertilizer to farmers. Zeldenrust said some of the fertilizer sold in the U.S. comes from Canada but most of it today actually comes from the countries that were once part of the Soviet Union, as well as Middle Eastern countries.

The FCD will be producing fertilizer in competition with those foreign sources, although "in the big picture, it's not even a fly speck. But it's a start," said Zeldenrust.

When it first became evident that a methane plant could be built in Fremont that would also produce fertilizer, "we were motivated to be involved with this, because if we didn't participate, we were going to be competing with it," said Zeldenrust.

He said North Central (then Fremont Cooperative) began its involvement with the proposed project almost six years ago; NOVI Energy got involved about five years ago.

Zeldenrust said there were years of setbacks as the project evolved. "But the good thing was, we were forced to continue our internal evaluation all the time."

"We are very satisfied with this project," he said. "We are going to be able to deliver on all the promises when it comes to noise and smell and safety, because we have been forced to go back and revisit this many times."

"With our business model, we think we are going to be extremely successful," said Zeldenrust, adding that the FCD "is going to be the first one of many" plants producing methane and fertilizer from food processing waste.

Recent Articles by Pete Daly

Editor's Picks

Comments powered by Disqus