Scott Dick and Cliff Loewen of Agra-Gold Consulting travelled to Europe in 2013 to investigate manure treatment technologies for the Manitoba Livestock Manure Management Initiative.
In Holland, they visited a dairy farm with a 75 cow herd that is one of the few livestock operations in that country with enough land to accommodate all the manure the animals produce.
Dick and Loewen found that although the dairy farm had enough acres of clay soil to legally apply all the manure, there wasn’t enough winter storage capacity to handle all the raw material. Managers of the farm had determined that they could extract 120 tonnes of solids by running 500 tonnes of raw dairy manure through a high capacity screw press plant.
Read Also
Land crash warning rejected
A technical analyst believes that Saskatchewan land values could be due for a correction, but land owners and FCC say supply/demand fundamentals drive land prices – not mathematical models
Regulations dictated that these solids could be applied to the land straight out of the separator, as long as they were plowed in immediately. This isn’t a problem because the ground seldom freezes solid.
A local fruit grower will take the excess solids as long as the dairy farmer delivers for free.
Liquid from the screw presses has a low percentage of organic nitrogen and is applied to forage crops the next summer.
The farm’s owners decided to contract out the manure management rather than investing heavily in their own on-farm system.
They made a deal with Verkooyen, a long-established custom manure brokerage firm, to build and own a mobile separator that the farm would pay $211 per hour to use.
Verkooyen started with six Doda screw presses mounted on the flat deck of a semi truck and eventually added four more screw presses. The unit cost $462,000 without the truck.
Manure is pumped to the mobile unit and fed through the 10 screw presses, which have a total capacity of 33,000 gallons per hour. Solids come off the tail end of the rig and dump into a field spreader. The spreader is also a rental unit, which helped lower the dairy’s capital investment.
Verkooyen said the unit doesn’t work as well with pig manure because it has a lower solid percentage and less fibre.
Performance is also reduced if corn is not part of the diet. Fibre is required for the screw press to operate efficiently.
