You can make asphalt and roof shingles from hog manure.
You can make biocrude oil that could be blended, just as ethanol now is, into gasoline.
You can use hog manure to generate electricity or heat or both.
But you can’t get rid of the offensive odours. Not yet, but researchers are working on it.
In fact, tens of millions of dollars have been invested in research looking for ways to curb hog manure odours and avert groundwater pollution, and that’s in only one state – North Carolina.
The issue was on the list for the Ontario Agricultural Research Institute about 20 years ago when the hog industry was in the midst of a barn-building boom and local residents were fighting to keep them as far from their homes as possible.
At the time, I was a director on ARIO and I suggested they let the U.S. take the lead and instead invest about $25,000 supporting a master's-degree at Wilfrid Laurier University in Waterloo to do a community-development project to determine what hog farmers could do to get along with their neighbours.
It wasn't a typical approach to agricultural research and it wasn't partnering with the University of Guelph, so good-old-boys network dismissed that idea and invested in copy-cat approaches being tried in the U.S.
Despite the millions spent so far, little has changed for odour-fighting neighbours of hog farms in North Carolina. Or Ontario. The farms still raise a stink - literal and political.
At the University of Illinois, Yuanghui Shang and Lance Schideman are producing synthetic oil from hog manure.
“We first convert swine manure into crude oil in a hydrothermal liquefaction reactor,” Schideman says.
“There is a very strong wastewater that comes off that process. It contains nutrients that can be used to grow algae that simultaneously clean the water.
“Lately, we’ve added low-cost, bioregenerable adsorbents into the system that allow us to grow additional bacterial biomass and further improve effluent water quality.
“Our recent research, a combination of experimental work and some computer modeling, has shown that we can reuse the nutrients multiple times and thus amplify biofuel production from waste feedstocks,” he said.
“If we start with a particular waste stream that has one ton of volatile solids in it, we might be able to produce three, five or even 10 tons of algal and bacterial biomass. This new biomass is then recycled back into the biofuel production process.
“It can also clean the water with the goal of making it suitable for environmental discharge or reuse in some other application. So we get more bioenergy and more clean water resources – both good things in the long run,” Schideman said.
“Right now, your gasoline has a certain amount of ethanol mixed in it. We are looking at other blending arrangements where light fractions of this oil could go directly into an existing fuel matrix.”
Hog manure has been used to produce a bio-binder that can be used to make everything from asphalt to roofing shingles.
Elham (Ellie) Fini, a civil engineer at North Carolina A&T State University, holds a patent on her invention and has started a company, Bio-Adhesive Alliance Inc.
There’s no indication yet that her invention is a money maker for either her company or hog farmers.
Her research was funded by the National Science Foundation.
None of this addresses the odour issue.
“For the people out there in the communities, nothing is really happening,” said Joe Rudek, a senior scientist with the Environmental Defense Fund in the U.S. “They haven’t really seen any changes in air or water quality.”
Nearly every one of about 2,100 hog farms in North Carolina still dumps hog manure into outdoor lagoons, then sprays the manure on fields.
The problems with odor, runoff from the spray fields and spills from lagoons still plague Eastern North Carolina, where most of the farms are located.
The number of lagoons, more than 4,000, is little changed since 1997.
Don Webb, a former hog farmer from Wilson County who became one of the earliest, and feistiest, community activists on the topic, said the years had simply worn down many of those who had been battling hog-waste issues.
“I’ve been fighting this myself for 25 years, and after all these years, we’re nowhere,” said Webb, 72.
“These companies, they’ve made millions of dollars while stalling for time, and they’re still able to pump feces and urine into those open holes just like they always have.”
Meanwhile, the conservative takeover of the legislature, he said, has resulted in cuts and reorganization among state regulators and reduced scrutiny of hog operations. In 2011, for example, the state stopped performing one of what had been two annual inspections at swine farms.
Deborah Johnson, executive director of the N.C. Pork Council, said pork producers would embrace a cleaner, cost-effective technology.
“If there is something out there, a (technology) that is affordable to growers and qualifies for permitting by the state, we would see growers that will adopt it,” she said.
The issue got so hot in 1997 that the state imposed a temporary moratorium on new or expanded hog farms that used the lagoon-and-spray method.
In 2000, Attorney General Mike Easley negotiated the Smithfield Agreement with the state’s main pork producers in which they agreed to several concessions, including paying $50 million over 25 years for environmental projects.
They also funded a $17.1 million research quest for a new method of treating hog waste.
This new method was to “substantially eliminate” pollutants and odor and completely stop waste from leaking into streams or groundwater.
The companies agreed that if one could be found that was affordable, they would install it on farms they own and also would help install it on farms they hired to raise hogs.
Researchers have found ways to answer the environmental issues, but they’re too expensive. There are specific cost targets set for the researchers to hit.
Julian Barham is using a methane digester to handle his hog manure, supplementing the mixture with food-company waste. He generates electricity and heat for the digester.
Another system removes ammonia. Some is used to grow greenhouse vegetables.
“When I got started in hogs, I had 200 sows and could make a pretty decent living,” he said. “Now I’ve got 4,000 and I struggle.”
The greenhouse cucumbers aren’t worth much, so the farm has to produce them in large quantity, too.
“There’s just no big, easy money in any one part of it, and you really need to wring every dime out of everything,” Barham said.
Several counties away, near Mount Olive, the other of the most promising technologies is set up on a sprawling farm owned by the Jernigan family that produces not just hogs, but also cattle, turkeys and row crops such as cotton.
It’s basically a series of lagoons similar to a municipal sewage treatment system.
It easily meets the environmental standards, and it also produces a sanitary dry solid that is composted by Terra Blue Inc. into high-quality soil additives for gardening and landscaping, but so far it’s costing more than four times the goal set for the researchers.
Terra Blue is working on ways to reduce the costs.
“After doing this for 20 years, I can tell you the issue is not so much the technology,” a Terra Blue researcher says. “The technologies are out there that can meet the environmental criteria. It always comes back to the cost.”
Getting paid for carbon offsets might work.
That’s why Google is investing in the project with Duke University and Duke Energy.
Tatjana Vujic, director of Duke University’s Carbon Offsets Initiative, said the university started the project not to make money, but to help reach its goal of offsetting all its carbon emissions by 2024.
Duke Energy got involved because the state is forcing utilities to generate some of their electricity from hog and poultry waste.
“I think the turning point will be when the economics look good, when the system pays for itself and brings something back to the farm, like carbon credits, electricity sales, lower mortality rates among the hogs,” Vujic said.
“It’s sort of like you need this perfect storm of things, all coming together.”
Meanwhile, there’s no word of any advances coming from the investments recommended by the Agricultural Research Institute of Ontario.