Used throughout history, and still used today in many parts of the world, human waste has a bad reputation as a fertilizer. Why? The chance that pathogens can be carried and inadvertently passed on through the food products grown with “night soil”. Not to mention the unpleasant, distinctive odor that the garden/crop lands take on with this practice.
Thanks to Pyrolysis, and with the ingenuity of its Swiss developers, human saste is being collected in mobile ‘dry’ toilets, then taken and processed by pyrolysis to become terra preta, a very fertile substance for growing plants of all kinds.
Source: The Straits Times
Martin Sturzenegger, Tages-Anzeiger
SWITZERLAND • If the banana trees at Zoo Zurich are particularly lush, it is thanks to a fertiliser with an unusual ingredient: human waste. During spring last year, zoo employees cleared a bamboo grove in Zurich’s Masoala Rainforest to plant the trees.
Within a few months, the saplings had reached an impressive height and produced a cornucopia of yellow fruit. “We were really surprised how fast the plants put down roots,” said Mr Martin Bauert, curator of the tropical area of Zoo Zurich.
The reason for this fast growth has a name – terra preta – which is Portuguese for “black soil”. It is a particularly fertile substrate created from compost, charcoal (biochar) and human faeces.
The company that provides Zoo Zurich with the fertile substrate is Greenport, started in 2015 by four friends. “We wanted to break some taboos with our products,” said Mr Tobias Mueller, a former carpenter and inventor.
To obtain the raw material, the start-up team developed a mobile dry toilet, the Greenport. The human waste drops into a container, which Team Mueller carts to a pyrolysis facility. Pyrolysis is the chemical decomposition of organic materials through the application of heat.
Read the entire article at The Straits Times