Waste-to-ethanol projects move forward

By Erin Voegele | October 06, 2009
Several projects that aim to produce ethanol from waste materials have gained traction in recent months. In the southwest region of the U.S., California-based Fulcrum BioEnergy Inc. is developing a project that will use a proprietary gasification process to produce ethanol from synthesis gas (syngas).

Fulcrum's technology transforms post-recycled municipal solid waste (MSW) into syngas, which is composed of carbon monoxide, hydrogen and carbon dioxide. A proprietary catalytic technology is then used to convert the syngas into ethanol.

Fulcrum recently announced that it has successfully proven its catalytic technology at its North Carolina pilot facility, the TurningPoint Ethanol Plant. The company is developing a 10.5 MMgy commercial-scale facility near Reno, Nev. According to Karen Bunton, Fulcrum's administration manager, construction of the Sierra Biofuels Plant is expected to begin in early 2010.

Indianapolis, Ind.-based Agresti Biofuels is also developing an ethanol plant that will utilize MSW. The proposed facility, which will be located in Pike County, Ky., was originally scheduled to break ground in late 2008. However, construction was delayed due to the economic crisis. According to Zbigniew "Zig" Resiak, Agresti's program director, construction is scheduled to begin as soon as financing is complete, which he estimates will in late 2009 or early 2010.

The proposed facility, which will be built adjacent to the existing Pike County landfill, will be constructed in phases, initially producing approximately 1.5 MMgy, later scaling up to 25 MMgy.

According to Resiak, Agresti and Pike County have partnered to complete the project. The county has provided Agresti with the landfill-adjacent site, which it is also preparing for construction through grading and utilities work. The county will also be the facility's sole feedstock provider.

Agresti's process utilizes four well-established technologies which Resiak said will be combined for the first time in one facility. In the first step of the process, MSW is dumped into a pool of water, where it is sorted into three groups: recyclables, cellulosic materials and metals. The cellulosic materials are converted into sugars using a weak acid hydrolysis process that utilizes gravitational pull vessels. The extracted sugars are then fermented into ethanol. In addition to the project in Kentucky, Agresti is pursuing similar cellulosic ethanol projects in Hawaii and Vietnam.

In New Zealand, LanzaTech NZ Ltd. has developed a proprietary fermentation technology that can be used to produce ethanol using waste industrial gases or biomass-based syngas. According to LanzaTech's co-founder Sean Simpson, industrial waste gases, such as those that result from steel processing, contain high concentrations of carbon monoxide. Carbon monoxide and hydrogen are also the main components of syngas, which can be created by gasifying any biomass resource, including MSW, organic industrial waste or waste wood.

LanzaTech has developed a proprietary non-genetically modified fermentation microbe that can be used to convert the carbon monoxide and hydrogen components of these gas sources into ethanol. "The carbon component is used as a food source for the proprietary LanzaTech microbe during the biofermentation process," Simpson said. "The microbe uses this energy to produce ethanol."

LanzaTech has tested its fermentation technology at a pilot facility located adjacent to the BlueScope Steel plant in Glenbrook, New Zealand. According to Simpson, LanzaTech expects to have the technology installed on a commercial scale at an established industrial facility by 2013.

Golden, Co.-based GeoSynFuels LLC is also working to develop a MSW-to-ethanol process. The company formed a joint research agreement with CleanTech Biofuels Inc., under which CleanTech will provide samples of MSW-derived feedstock for GeoSynFuels to use in its proprietary enzymatic hydrolysis process.