More ‘ gold ’
With up to 13 litres of water — or as much as 25 – 35 % of all domestic use — being used for flushing toilets , it is time for cities to move on to non-water toilet systems , says Jayant Bhagwan of South Africa ’ s Water Research Commission ( WRC ).
Municipalities and entrepreneurs must start to view human faeces and urine as “ brown gold ”, rather than seeing its disposal as a problem , he adds .
The percentages of water cited , he says , is to “ move around 150g to 200g of human waste … and then we use another 150 to 200l to convey it down the system ”, he adds . However , by turning human waste into products , thousands of jobs could be created , Bhagwan points out .
He was one of the speakers during a session at the biennial conference of the Water Institute of Southern Africa , in Cape Town .
Bhagwan ’ s message is simple : human waste is a valuable commodity that can be monetised for profit , rather than soaking up valuable water resources .
Many of the sewers in use in cities around the word pre-date “ bathrooms as we know them ” and water sanitation accounts for 60 % of the cost of disposing of human waste . “ Yet people are conditioned into viewing flush toilets and centralised sewage treatment works as the preferred options … the ‘ gold standard ’ … while the poor are excluded .”
And as the world runs out of its traditional sources of energy , potable water , and plant nutrients , water resources are declining , energy costs are rising , and climate change is an issue .
Despite this , the basic design of toilets has barely changed over the past 200 years , he says , adding that current types of toilets , including flush arumloo
The Arumloo , which uses just two litres for a full flush .
and chemical toilets , pit latrines and septic tanks , were “ full of problems ”.
An example of an innovative solution and design is the Arumloo , which has the same lines as an arum lily . It uses just two litres for a full flush and the designer is trying to reduce this to just half a litre a flush . Other innovative systems that are showing promise include experimenting with drying , dehydrating , biological , carbonisation , combustion , solar , and thermal treatment for the disposal and repurposing of human waste , says Bhagwan . Some prototypes of different new-age toilets are already being tested in South Africa .
Jayant Bhagwan speaking at the WISA 2018 conference .
WISA innovations industry debate environment infrastructure municipalities