Where City Meets CountryPosted in: Environment By Tracy Tjaden March 1 2013
Returning Biosolids Back to the Land
An Ontario university start-up has big plans to help Canadian cities deal with waste management woes, ease farmers’ concerns over rising input costs and feed the world along the way. Cambridge, Ontario-based Lystek International Inc. has a technology that converts biosolids or treated sewage into a fertilizer registered with the Canadian Food Inspection Agency. The company installs its technology at a city or municipality’s wastewater treatment plant, and has also started working with food processing plants that are generating high volumes of biosolids, such as hog plants, dairies or feedlots. It has also started constructing stand-alone Organic Materials Re-source Recycling Centres, which process biosolids from nearby communities or plants and make the fertilizer available to farmers. The first centre is expected to be up and running in Ontario in April.
New technologies are being developed to turn waste into energy
“It’s irresponsible to put the nutrition of biosolids into a landfill because basically you are wasting these essential nutrients,” says Dr Owen Ward, who co-invented the technology at the University of Waterloo in 1999 and is one of Lystek’s founders. Returning biosolids to farmland completes a natural cycle, he says: Farms produce food that is consumed by humans, who produce biosolids that can then be returned to farms to produce more food, and the process continues.
Going forward, plant nutrition is going to play a vital role in the global challenge to sustain the world’s food supply, says Ward, a former president of the Canadian Society of Microbiologists and former director of the U.S. Society of Industrial Microbiology.
Chemical fertilizers typically restore soil’s nitrogen, phosphorous and potassium levels, which intensive farming and harvest techniques can deplete over time. But Ward says farmers and the agriculture industry as a whole needs to consider alternatives. “The basic sustainability issue here is that chemical fertilizers are being depleted — some experts are saying phosphorous will run out by the end of the century,” says Ward. “These fertilizers are like petroleum; they are a limited resource and will get used up.”
Nutrients found in biosolids are essential for plant growth. N, P and K are the key ones, but trace elements such as calcium, copper, iron, magnesium, manganese, and zinc are also necessary for crop production.
Properly treated biosolids can supply these, cut farmers’ fertilizer costs and divert urban waste from local landfills. One agriculture industry expert says this is why demand for such alternatives is on the rise.
“We’re seeing more and more pressure around urban areas to apply biosolids to the land, and as a result the technology is improving,” says Al Mussel, senior research associate with the George Morris Centre, an agricultural think tank based in Guelph, Ontario.
Lystek’s process uses a combination of heat and potassium hydroxide to break down cells and kill the pathogens found in biosolid materials. The final product is 17% solid content, but still in liquid form so it can be applied to farmland using a conventional manure spreader.
The system is currently being used in several municipalities in Ontario and Litwiller says it is now in talks with a few cities in Western Canada. In order to be accepted for registration as a fertilizer by the CFIA, the end product must meet all required guidelines for health and safety. The quality assurance process begins with provincial oversight and at the treatment plant, where the raw material is subject to ongoing testing by regulators with the province’s environmental ministry.
Once the material has gone through Lystek’s physical and chemical process, it is tested again by internal staff and then submitted to the CFIA for fertilizer registration. Registration occurs on a plant-by-plant basis.
According to an agriculture biomass researcher with PAMI, there are several processes available to convert farm waste into value-added materials. What’s missing is the economic model needed to make it happen.
“The main hurdle for developing these technologies is the financial aspect — there is no dollar value in our economic system now connected to sustainability,” says Joy Agnew, project manager at the Applied Bioenergy Centre at PAMI.
Agnew’s focus at the centre is to research and evaluate new technologies for use of bioenergy in agriculture. One of its main projects is finding ways to privatize agricultural biomass, which includes straw, manure, etc.
The group is working on several conversion technologies for turning this waste into energy, such as gassification, combustion and other anaerobic methods. It is also conducting biomass plot trials to find ways to lower the cost of producing energy crops.
“It’s value-added agricultural waste management,” she explains. “We look at ways to make agriculture more sustainable — and society more sustainable.”
Projects that are the closest to market involve conversion of agricultural biomass for electricity generation. Both the Ontario and Manitoba provincial governments have mandated the eventual elimination of coal for electricity generation.
“So on a very large scale Ontario Power Generation is now procuring and processing biomass and treating it to replace coal,” says Agnew. “They were initially using forestry residue but can’t meet all their targets with just wood, so they’re looking at ag biomass.”
Canada lags behind other countries in finding sustainable uses for biosolids. In Australia, over 80% of biosolids end up back on agricultural land, says Ward. In the United Kingdom, it’s close to 60%. “This is a country that has a population density 65 times greater than Canada’s, that is part of the reason,” says Lystek’s Ward. “Apart from the ethical reasons for not putting this stuff in landfills, there is a practical aspect of landfill capacities and in the UK this is very serious.” Edmonton and Calgary both have biosolids application programs, and Winnipeg is investigating this option. The City of Calgary’s program, Calgro, recycles more than 20 million kilograms of biosolids annually to local farmland for about $3.50 per capita per year.
Litwiller says that initially, as Lystek demonstrates how its technology works in the marketplace, it will provide its fertilizer to farmers for a nominal fee.
Food processing plants or urban centres that provide the biosolids to a Lystek plant will pay a tipping fee. “For the next three or four years, 90% of our revenues will come from tipping fees from the generators of the materials,” says Litwiller.
“Our long-term economic sustainability depends on having a happy customer in the farmers, they are our end customer.”
In five years, he predicts 60% of the company’s revenues will be generated by tipping fees, with the balance coming from fertilizer sales. Ward and Litwiller point out that companies such as theirs won’t be edging out the big fertilizer producers any time soon. Even if all of the biosolid waste available in North America was being used on farmland, it would still only represent 4% of the total fertilizer market.
Instead, Ward says it’s about changing what society views as waste. “Our vision for the company is that people look at this differently — that we are not dealing with a waste, which dismisses the value, what we are dealing with is a resource,” he says. “I’ve spent my life developing these processes and when I look at biosolids, I see that what we are actually building is a manufacturing plant for fertilizers.”
The George Morris Centre’s Mussel says converting urban biosolids into fertilizer in pellet form would open up even more options, as the product could be marketed and shipped anywhere rather than only to nearby farms. The challenge lies in ensuring the uniformity of nutrient composition of the pellets.
Mussel agrees that concerns around depletion of phosphate will likely drive future growth of this market. “I suspect it will be like oil — as phosphate prices go up people are going to look harder for alternatives,” he predicts.
“If you’ve got a material that is capable of meeting nitrogen specs, and it can be made reliably uniform and dry enough that you can truck it, then yes that could be very significant.”
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