Alabama plant to begin producing ethanol from waste wood

Published: Jun 23, 2008 1:00:00 AM
Media Contact: Thomas Spencer, tspencer@bhamnews.com,

Source: Birmingham News

LIVINGSTON - In a cavernous, abandoned lumber mill in the Black Belt, a small team of engineers and technicians is assembling a demonstration plant that, as early as this month, will start turning wood scraps into ethanol.

The plant would be one of the first in the country to use a technology called gasification on wood waste. Most ethanol and biodiesel plants use fermentation to turn soybeans or corn into fuel.

If the plant runs as advertised, the company - Gulf Coast Energy - plans to expand on the site with a $90 million commercial-scale plant, which it says will be capable of producing 45 million gallons of ethanol a year.

To put that in perspective, in Alabama we use about 2.5 billion gallons of gasoline per year, according to Steve Taylor, the director for the Center for Bioenergy and Bioproducts at Auburn University.

The plant will use a process called gasification to produce fuels from local sources of waste sawdust and scrap timber, materials that otherwise would be burned, landfilled or left to rot.

Gulf Coast Energy, a startup company whose board chairman is Livingston lawyer Drayton Pruitt, is one of a handful of companies around the country exploring the use of gasification on nonfood plants.

With petroleum prices soaring, the demand for alternatives is growing. Corn-based ethanol is the most established biofuel, but some have begun to question whether it's the best option. Corn grown for ethanol competes for land that could be used to grow food.

Raising corn also involves the use of petroleum-based fertilizers and gasoline-powered machinery. And the process for converting corn to fuel, a form of fermentation, isn't as efficient as it is for other crops and using other technologies.

Gulf Coast Energy is not alone in exploring the use of gasification on wood waste. Another company, Range Fuels, which is backed by Silicon Valley entrepreneurs, has begun construction on a commercial-scale plant in Soperton, Ga. The gasification process is not new, either, but has primarily been used on coal.

Germans gasified coal:

The Germans gasified coal to fuel their armies after the Allies cut off petroleum supplies during World War II. Facing an oil embargo during the apartheid era, the South Africans used coal gasification to produce gasoline.

The plant material - which can be wood waste, switchgrass or any carbon-based material - is ground very fine, then fed into a dryer. The dried material is subjected to high heat, which breaks apart the hydrogen, carbon and oxygen molecules and forms a synthetic gas. That gas is then subjected to a chemical reaction called the Fischer-Tropsch process, which reassembles the molecules into fuels such as ethanol, butanol, methanol and propanol.

Pruitt said Gulf Energy's process was designed by a Mississippi inventor and the demonstration plant was disassembled and moved from Aberdeen, Miss. He said the company won't disclose the identity of the technology's developer, saying only that he worked in the chemical industry and developed the technology using his own money and grants. But he is confident it will work on the larger scale.

"It has the highest yield of any of the technologies we looked at," Pruitt said.

The process uses a closed-loop system that doesn't emit carbon dioxide. After the initial reactions are started, the plant can power itself, recycling heat and using the fuel produced.

"It is an extremely efficient process and an extremely clean process," Pruitt said.

Figuring out what to do with waste products has long been an interest of Pruitt's. He was one of the originators of the hazardous waste landfill at Emelle, also in Sumter County and now operated by Chem Waste.

On this venture he is working with engineers Mark Warner and Scott Hazen, who previously worked at the Mercedes plant in Vance. Pruitt says he has put together enough venture capital to start construction of the commercial-scale plant almost as soon as the demonstration plant is up and running. If construction begins in July, the company expects to complete the project in 14 months.

David Bransby, an Auburn University professor whose research focuses on plants like switchgrass that can be used as fuel, said he didn't know anything about the particular technology Gulf Energy is using, but said "the general technology is one of the better-looking technologies."

Ton of biomass:

A ton of biomass should have the equivalent energy content of 2.5 barrels of oil, Bransby said. With oil trading in excess of $120 a barrel, a ton of biomass, if you were able to efficiently extract the energy from it, should be worth $250. But according to Bransby, right now you can get wood at less than $50 a ton. That creates a financial incentive to achieve an efficient method of converting biomass energy into fuel.

"I believe you are going to see some remarkable progress in the next few years," he said.

Auburn's Steve Taylor said that even if the conversion of wood to fuel was perfected, it shouldn't lead to an environmentally destructive race to cut down Alabama forests.

According to Taylor, there are 4 million tons of logging debris, limbs and tops left on the ground under current timber practices that either rots or is burned. In addition, there are trees that are too small to be marketable, even as pulpwood. Auburn estimates that Alabama could provide almost 15 million tons of wood waste annually without increasing logging.

The problem is finding new ways to efficiently get that material to a processing site. "It is not cost-effective to package it and bundle it up," Taylor said.

Researchers are looking at ways to create portable gasification plants that would be able to convert the wood waste to fuel on the site.

Regardless, it would be a long time before demand for wood waste caught up to supply.

Mark Warner, Gulf Coast's CEO, said he imagines a future in which small-scale biofuel plants make use of locally available sources to make fuel and supply a community in a 50-mile radius.

In his opinion, such a model is not as far away as some think. "We are farther along than the general public realizes," Warner said.

Scott Z. Hazen, Gulf Coast's executive vice president for construction and engineering, said a realistic goal is that biofuels could provide 25 percent of the country's energy by 2025.