Efforts to remove phosphorus and nitrogen from manure are particularly relevant in the Fraser Valley, which is home to 500 dairy farms
VANCOUVER, B.C. — A Vancouver college is looking for new ways to manage manure in British Columbia’s Fraser Valley.
Working with Muddy River Technologies of Delta, B.C., researchers at Langara College are seeking a cost effective way to prevent soil degradation and water contamination by removing phosphorus, nitrogen and other byproducts from animal manure.
The Fraser Valley is home to about 500 dairies, and the high amounts of slurry cause environmental and economic problems. Farmers do not have enough land to dispose of it, and they cannot expand because of the limitations placed on them by excess manure, said Langara researcher Kelly Sveinson.
This spring the college received $90,000 from the B.C. Innovation Council Ignite Award to support the project involving Sveinson, chemist Todd Stuckless and Rob Stephenson, chief technical officer of Muddy River Technologies, which works on water and waste treatments.
The project involves removing phosphates from manure using an electrochemical process similar to that used in environmental cleanups. The second step is to use a biochar carbon filter to capture ammonia that can be released as nitrogen. Ultimately those products could go back on the land as fertilizer.
“Ammonia is a valuable commodity and really it belongs back in the soil,” said Stuckless.
“We are trying to capture it on charcoal, and the charcoal is a good soil amendment and now it is enriched with the ammonia and it has been shown to act (as) a good fertilizer.”
Biochar can be derived from organic materials such as wood chips, manure or spent mushroom substrate that was cooked in a kiln in a process called pyrolysis. Depending on the temperature, it can come out resembling charcoal briquettes or a fine, granular material.
It is a good soil amendment that sequesters carbon in the soil and provides agronomic benefits.
The key is making the whole procedure economically feasible.
“In the valley, there is lots of biomass and lots of ammonia so if you could convert the biomass to biochar and use the biochar to absorb the ammonia and put it back on the soil, then the soil would grow biomass,” said Sveinson.
“That beautiful cycle is what we are imagining would be the ideal, but the economics of it is what we will work through.”
Making biochar is easy enough, but the researchers need a cheap organic source of material.
“We are trying to find the cheapest source of material, especially if it is available in a place where someone wants to get rid of it,” Sveinson said.
“The economics would allow for the cost of trucking but not much more than that. If it is a waste product someone wants to get rid of, it would work, but if we have to pay for it, it wouldn’t work.”
Soil in some parts of the Fraser Valley region needs more nitrogen and phosphorus. Phosphorus supplies from overseas are depleting so this could be one way to create a homegrown product.
The dairy sector in the Fraser Valley could fill a football stadium full of manure every year. Using Vancouver’s Pacific Place Stadium as an example, the manure could pile up on 10 acres of land, 17 stories high every year, said Stephenson, a former research scientist with the National Research Council.
The next phase in this project involves Seabreeze Farms at Delta, about 40 minutes away from the urban-based college. The farm has about 350 cows and has been using an anerobic digester to process manure since 2015. The byproducts include methane for energy generation, bedding for the cattle and nutrient removal.
A few farmers are using digesters, but many say they are too expensive.
“There are far cheaper ways to build a digester which are almost always simpler ways to do it without compromising it,” said Stephenson.
“There are so many bad examples that the industry basically said it either doesn’t work or it is too expensive.”