Iowa to get first biomass-to-ammonia plant

By Susanne Retka Schill
SynGest Inc. has secured a site in Menlo, Iowa, to build what it says is the world's first biomass-to-ammonia plant, to help supply the U.S.'s 18 million ton per year ammonia market. The San Francisco-based company has developed gasification and syngas technology to deploy in its first plant. The technology will be used to annually turn 150,000 tons of corncobs into 50,000 tons of anhydrous ammonia, which is enough to fertilize 500,000 acres of land.

The process involves a pressurized oxygen-blown biomass gasifier operating in an expanding bed fluidized mode. The company's patent-pending HarvestGas system gasifies biomass into a mixture of hydrogen and carbon monoxide, and is optimized to minimize the formation of methane. After the gas stream is cleaned, the carbon monoxide portion is shifted to maximize hydrogen. The hydrogen is purified and catalytically reacted with nitrogen to make ammonia. The plant includes an air separation system to provide oxygen for the gasifier and pure nitrogen for ammonia synthesis.

The gasifier is a variant of existing designs used for coal gasification, explained Jack Oswald, SynGest chief executive officer. "We run at lower temperatures and pressures than comparable gasification units, thus we have our own design that is cheaper to build," he said. "Everything else is off-the-shelf technology to minimize technology risk."

The plant will fit on five acres of the 75-acre site at Menlo, with the remainder available for biomass storage. "The size of the facility is driven by the logistics of biomass collection," he said. The plant will require 10 percent of the available corncobs from a 30- to 40-mile radius.

Because 90 percent of the cost of anhydrous ammonia is determined by the cost of natural gas, the company's product may be more costly than conventional anhydrous ammonia when the price of natural gas is low, Oswald said. The higher cost will be offset, however, by the lower cost of transporting the product, which is predominantly produced in the Gulf, to the Corn Belt.

Financing for the $80 million facility is close to being finalized, according to Oswald, and negotiations are underway with a large agribusiness firm to handle both feedstock procurement and ammonia off-take. Depending on how the permitting process proceeds, groundbreaking will happen this fall or next spring. Construction is expected to take 18 months.

As project development proceeds, SynGest is examining the provisions in USDA's new Biomass Crop Assistance Program. BCAP pays farmers 75 percent of the cost to establish bioenergy crops and helps with collection, harvest, storage and transportation of biomass to a production facility. Oswald said the initial discussions they've had with USDA were well received.