Sustainable Energy Systems
Clean Diesel from Coal and Urban Waste
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San Bernardino Sun reporter Andrew Silva listens as Viresco Energy President Jim Guthrie explains some of the technology in transforming such materials as coal, wood or muncipal waste into diesel fuel. |
Current Projects
Now, a Riverside private-sector firm has stepped forward to take it from the bench scale of CE-CERT's laboratories to a 15 to 20 tons-a-day pilot plant.
Viresco Energy, LLC is a venture of its president, Jim Guthrie, and a number of investors. At a press conference in late 2006, Guthrie unveiled plans for a $15 million plant to test CE-CERT's technology at the higher level. If things go well, Guthrie envisions a commercial plant, perhaps in a Utah coal field, in five to ten years.
The process, which is in the process of being patented, uses high pressure and heat to break down carbonaceous materials, such as coal or wood waste, into methane. The methane can then be converted to diesel fuel through the established Fischer-Tropsch process.
The new CE-CERT process configures three thermo-chemical process reactors that can produce nearly pure paraffin hydrocarbon liquids (similar to petroleum-derived diesel fuels) and wax-like compounds (similar to petroleum-derived paraffin jellies). These waxes can be processed to produce even more liquid paraffins. The process is self-sustaining, without the need for additional fuels or energy sources.
A Laboratory Scale Integrated System Prototype (LISP) for a unique carbonaceous matter-to-energy process was designed, constructed and proved promising. The LISP consists of three main components: hydrogasification of the carbonaceous material, steam reforming of the producer-gas and Fischer-Tropsch synthesis of reformed gas into diesel fuel. Associated with the integrated process is a slurry pump system for feedstock and a hot producer-gas clean-up system for protecting the downstream catalysts from potential impurities in the feed.
"One of the advantages of this is we will reduce the need for imported oil," Norbeck told the San Bernardino Sun. Diesel fuel could be produced for about $1 a gallon, although the retail price would be higher, he said.
The techniques for turning carbon-based solids into fuel have been around for centuries. Faced with boycott for its former apartheid policies, South Africa produced virtually all of its liquid fuels from coal.
However, those processes were not as inexpensive as petroleum-based fuels and were often quite dirty.
CE-CERT's new process holds the promise of being cost-effective, especially if oil prices remain high, and having few environmental side effects.
The fuel lacks sulfur, oxides of nitrogen and other pollutants, said Neal Richter, Viresco's technical adviser.
The new process can be completed in six minutes, whereas earlier methods took an hour for the transformation. Norbeck said the research team isn't sure of the reasons for the difference, but the new processes uses hydrogen and steam at close to 1,500 degrees to break down the carbonaceous material into gases. Earlier methods used oxygen, he said.
Viresco Energy also is talking with the city of Riverside about using sludge from its sewage treatment plant as the raw material for a a 400 ton-per-day plant, said Guthrie..
Such plants, if successful, would open a whole new market for Viresco and give cities an alternative to waste disposal.