Hundreds of years ago, it was common practice for all the sh*t in a town or city to be gathered up each night and dumped on the nearby fields as fertilizer. This provided excellent nutrients for the crops, but it also created a lot of disease.
Scroll forwards hundreds of years later, and we still have to wash our fruit and veg because of all the chemical sh*t dumped on it. More to the point, real sh*t is being looked at again as a sustainable substitute for chemical and phosphate fertilizers used in intensive agriculture.
Back in December 2010, the UK Government announced it was looking seriously at ways to include anaerobic digestion (AD) in the country’s waste processing and energy production networks.
AD breaks down waste (including sh*t) in an airless environment, producing biogas for energy consumption and a nitrogen rich solid by-product known as digestate.
Now, the UK has announced a four year programme to investigate using digestate as an alternative farming fertilizer, which could end up seeing the use of chemical and phosphate fertilizers completely replaced on many farms in the country.
The principle is well known and digestate is frequently used as fertilizer in small scale AD installations in China and other countries. However the UK’s planned AD network goes way beyond anything most countries have in place and could well see the end of intensive agro-chemical fertilizers in the country.
Picture Credit: Slurry spreading tractor and trailer by desomurchu under Creative Commons Attribute License.
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