[Lapg] [cityrepairla] methane digesters are the sh...t

[Jeremy Drake]

Often times the digestate (solids left over after anaerobic digestion)  
is land applied as fertilizer as it is very high in potassium as well  
as nitrogen (and usually salts too, slightly less appealing).

Other times it’s composted then used as, well compost. This is common  
practice in California cities such as Oakland that anaerobically  
digests biosolids (poop) at their wastewater treatment plant. As long  
as the digester really cooks (131 fahrenheit for 3 days) pathogen kill  
is achieved and any “threat” is gone.

In which case I would argue that our excrement makes exactly ZERO  
pollution when processed appropriately.

 From California Composting Regulations, Title 14, Division 7, Chapter  
3.1:
At enclosed or within-vessel composting process operations and  
facilities, active compost shall be maintained at a temperature of 55  
degrees Celsius (131 degrees Fahrenheit) or higher for a pathogen  
reduction period of 3 days.

Thanks Curtis.

Jeremy

ps - an exciting tangent on the Oakland thing is that they are now co- 
digesting commercial food scraps collected by the city in the WWTP  
digesters. Now that is some GHG reduction AND methane power!

Note: vegetative food scraps are also very high in nitrogen....



On Aug 20, 2010, at 4:02 PM, CURTIS BLANKINSHIP wrote:

> This is a link to a small scale methane digester. the extra water  
> tank is used to create pressure to use the gas for cooking or  
> powering a generator.
> does everyone get that we can produce power from our own excrement  
> with very little pollution. This would get us back withing earths  
> cycles ( see Nitrogen cycle ) instead of working against them which  
> enables a small group to maintain power.
> Curtis
>
>
> http://www.youtube.com/watch?v=l5e_2W71jMM

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.permaculture-guilds.org/pipermail/los-angeles-permaculture/attachments/20100820/b2a7a94c/attachment.html>