Reduce, Reuse, Peecycle?

Big thanks YET again go out to Linton from Hugg for the recent Pee-cycling posting (go give it a ‘Hugg’ already, will ya?), which mentions a recent article in New Scientist Magazine.

It’s really interesting how closely I (accidentally) timed my posting about Carol Steinfeld’s “Liquid Gold” book to the publication of the New Scientist article (I’m still waiting for that issue myself).

What’s cool is the fact that the magazine has published an online copy of the Pee-cycling article on their website.

According to the article, while urine only contributes 1% to the volume of waste water, it is responsible for a whopping 80% of the nitrogen and 45% of the phosporous in this waste stream. That’s pretty significant.

Not only do conventional waste water plants consume an incredible amount of water, but they also require a great deal of energy for the various nutrient-removal stages.

So what can we do about it?

Well, until such time as there is a massive overhaul of the conventional wastewater management model, you can do as Carol Steinfeld suggests in her book and simply separate it yourself using either low-tech (bottle) or high-tech (urine separating toilet) and then simply use it around your property as a fertilizer (remember, unlike feces, urine is essentially sterile in healthy individuals).

Here is an interesting blurb from the New Scientist article:

The whole process [wastewater treatment] is very good at converting yellow, black and grey water into more or less clear water, but all that pumping, stirring, aeration and heating uses a lot of power - about 11.5 watts per head of population. That’s only a tiny portion of your personal daily energy consumption, but it mounts up. In the UK, population 65 million, it means waste water treatment consumes 65,000 gigajoules a day - about a quarter of the output of the country’s largest coal-fired power station. In a world where energy efficiency is ever more important, that’s not to be dismissed.

According to civil engineer and urine-separation expert Jac Wilsenach, it’s highly inefficient. Wilsenach spent six years at Delft University of Technology in the Netherlands working on the intricacies of sewage systems, and according to his calculations, today’s methods mean we are literally flushing energy down the pan.

In a paper published last March, Wilsenach calculated that if we were to separate out just half of our urine, the microbes in the aeration tanks could eat up almost all the nitrogen and phosphate (Journal of Environmental Engineering, vol 132, p 331). The energy-intensive polishing stage would become completely unnecessary.

There’s another, even bigger gain to be had from separating out the urine. Lower starting levels of nitrogen and phosphate mean that the microbes in the aeration tanks can do their job much more efficiently, taking just one day compared with about 30, thus reducing the energy demand of the aeration tanks. What’s more, the resulting sludge is richer in organic matter and generates more than three times as much methane. In fact, says Wilsenach, separating out 50 to 60 per cent of the urine could turn sewage works from net consumers to net producers of energy to the tune of about 2.5 watts per person.

I highly recommend you read this excellent article. Again here is the link: Pee-Cycling

Technorati Tags: wastewater, sewage, waste, urine, toilet, pee, waste treatment, fertilizer, new scientist, water, resources

Written by Bentley on December 21st, 2006 with 3 comments.
Read more articles on Waste Management.

• [+] Digg: Feature this article
• [+] Del.icio.us: Bookmark this article
• [+] Furl: Bookmark this article

Related articles

• Gomi Style - DIY Dumpster Design (January 24th, 2008)
• Winter Composting Update (January 3rd, 2008)
• Winter Composting Extravaganza II (December 11th, 2007)
• My New Website (December 11th, 2007)
• Winter Composting, Take Two and…Action! (November 7th, 2007)