Scientists like to have lab test scale projects to discover and debate for years on end, farmers and practicing industries move forward when it is clear what works.
Treating liquid manure with biochar,
the Biochar Journal 2014, Arbaz, Switzerland.
Version of 01 th September 2014
Treating liquid manure with biochar
by Hans-Peter Schmidt
One of our oldest preconceptions is that a cowshed inevitably stinks. But the pungent odour of liquid manure is first and foremost the sign of a microbial decomposition process that has gone out of control. That which stinks to high heaven is not only an offence to delicate citizens’ noses but above all a source of disease for the animals living there. Thanks to biochar and to the control of the microbial environment in the shed and in the manure pit, materials cycles can be closed. Liquid manure in this way becomes a highly efficient, sustainable and odourless fertilizer.
In spring and autumn, when farmers spray their fields with liquid manure, an acrid stench spreads across the countryside. This pungent smell comes especially from ammonia, a volatile nitrogen compound formed from the urea contained in the manure. Large portions of the ammonia, which is corrosive to soil organisms and fine roots, escape into the atmosphere, where it binds to dust particles and returns in the form of acid rain onto fields, forests, cities and water systems, causing major environmental damage. …
Liquid Manure Treatment
Biochar adsorbs efficiently Ammonia, Ammonium and other odorous organic substances. While in non-treated liquid manure lagoons more than 30% of Nitrate is lost to the atmosphere, the treatment of liquid manure with biochar, lactobacilli and rock powder nearly all Nitrogen can be stored in a plant available form. As the fertilizing efficiency further increase, the fertilizer capacity of the manure nearly doubles.
Using biochar for the liquid manure treatment reduces leaching of the manure treatment to the subsoil, which protects the groundwater and avoids soil acidification. The biochar treated liquid manure enhances biological soil activity and helps for the build-up of soil organic mater.
0,6% - 1% (vol) Biochar based on the total volume of the liquid manure (if biochar is milled, the application quantities can be reduced)
Add the biochar regularly to the manure lagoon.
Even more important than the application of biochar is the guidance of the microbial milieu in the manure. Bad smelling rotting has to be avoided. Putrid smells are an unmistakable sign of bad manure quality. To guide the microbial milieu, we recommend to use the commercial product EM-A or self produced IMO (indigenous microorganisms). Adding rock powder further helps:
0,1 % (vol) EM-active or up to 0,5% (vol) IMO
2-3 % (m/m) rock powder
Only a few days after the treatment, the lagoon will not smell bad anymore. However, soil application of the treated manure should be done only 20 days or more after the treatment to allow the microorganisms to finish their job.
We suggest to start the liquid manure treatment when the lagoon is still rather empty. You can thus avoid nutrient losses and climate gas emissions. We further recommend to use biochar already in the bedding and to spray regularly EM-A and IMO in the barn.
ithaka institute for carbon strategies
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