In Utah, manure from 23 farms owned by Smithfield Foods will be used to produce metanol. Then, when combined with animal fat, soybean oil or used cooking oil, will make biodiesel fuel for tractors, trucks and other uses.
The packer is investing $20 million and is the majority partner in the operation with the technology provider, BEST BioFuel LLC.
Pending final permitting, construction of the digesters and methanol facility on one of the company’s Circle Four Farms near Milford, UT, will start in April. Production could begin as early as October. After market research, an out-of-state site for a biodiesel plant will be selected.
Liquid manure from weekly under-slat flushing of about 75 finishing barns will go through a "thickener" to remove most of the liquid. Each of the barns has 4,000-head capacity.
Garth Boyd, the company’s director of environmental technology, explains to Pork, "Unlike a conventional solids separator, the thickener concentrates the solids by gravitational settling. This reduces the liquid volume going to the digester by approximately 75%.”
Semi-solids go to into a continuously-mixing digester and heated to 95 degrees F. to make biogas. About 20% of the gas will be used to run the digester. The remainder will be converted into biomethanol by a thermo-catalytic process.
Overflow from the thickener and liquid from the digester will contain negligible organic matter, says Boyd, and will be piped back to existing, lined lagoons and to lined evaporative basins.
"In Utah’s high-desert country," he continued, "a liquid evaporates so quickly that no land application has ever been required.”
He said the small amount of solid residue produced by the digester will be removed and returned to existing lagoons.
Boyd also told Pork that there are no immediate plans to extend the manure-utilization technology to other Smithfield-owned farms. "Here in North Carolina, our farms are so scattered that a pipeline-collection system would not be feasible. An option may be to separate solids on farms and truck them to a central location.”