Sludge Watch ==> Better to use sludge for energy - stabilized manure for fertilizer

[Maureen Reilly]

Sludgewatch Admin:

Sigh…
Lets parse this story…it explains in some detail how to do it all wrong…from 
a public health point of view.

It suggests that we take cow manure and digest it for methane.
That methane would be used to dry sewage sludge into so called ‘Class A’ 
sewage sludge.
Class A sludge is supposed to have fewer pathogens, but recent reports show 
that pathogen regrowth and reactivation rates can be very high in sewage 
sludge.

It then suggests that farmers try to sell or use or give away the resulting 
dried sludge as fertilizer for VEGETABLES!

Well lets slow down a mite.  Cow manure has much lower levels of toxic heavy 
metals, drugs, and chemicals than sewage sludge.  So it makes a better 
fertilizer.  Also most grocery chains refuse to buy vegetables grown in 
sewage sludge through secret producer supplier contracts…no matter what 
‘class’ of sludge is used.

This story has it backwards.  Better to use sludge for energy and composted 
manure for fertilizer.


……………………………………………………………..

Local News – Washington State
________________________________________
Published: Monday, June 25, 2007
Putting waste to good use
Monroe may recycle sewage sludge with farms' manure
By Lukas Velush
Herald Writer

MONROE - Cow manure, meet human waste.Local dairy farmers trying to stay 
competitive want to turn cow dung into an asset.

Typically dealing with the waste, which is more plentiful than the milk the 
cows produce, is one of the most expensive parts of running a dairy.
At the old Monroe Honor Farm, manure from three Tualco Valley dairies will 
be cooked in a device called a bio-digester, say supporters of the plan.

As soon as early next year, the methane given off as the manure decomposes 
will be burned to generate electricity that can be sold to Snohomish County 
PUD.
Nearby, Monroe is running out of room to convert the sludge left over from 
its wastewater treatment process into compost.

So, instead of hauling the sludge to a remote site at a huge expense, the 
city has proposed trucking it two miles to the honor farm site.
There, the city wants to use some of the methane to fuel a dryer that would 
cook the sludge, condensing it into a commercial-grade fertilizer.
In turn, the farmers aim to use the fertilizer to grow corn to feed their 
dairy cows, generating more manure, and of course, milk.
"There's a self-sustainability to this plan," said John Lande, the city's 
wastewater treatment plant manager. He also called it "environmentally 
friendly" because it keeps methane, a greenhouse gas, out of the atmosphere.
The city last week agreed in principle to buy methane from the farmers for 
use in the sludge dryer. But that agreement won't be made official until a 
feasibility study is conducted. The city hired a consultant to figure out 
how to make the project work.

Lande said he expects the partnership with the farmers to be at least five 
times cheaper than shipping the sludge out of the city for treatment.
The farmers are calling it a win, too.

"The kicker here is, when they're done drying their product, it'll be a 
Class A material that can be used anywhere on anything, including on 
vegetables," said Dale Reiner, one of the farmers involved in the project. 
"We'll use that as fertilizer on our farmland. We won't need as much 
commercial fertilizers."

The farmers also could make more money selling methane directly to Monroe 
than they would using it as fuel to create electricity for sale to the 
Snohomish County Public Utility District.
The savings come because 62 percent of the energy potential is lost when 
methane is burned to create electricity, Reiner said. Only 10 percent of 
that energy potential is lost when methane is used to dry sludge.

The farmers don't know how much methane to expect from the waste of up to 
2,500 cows, but they expect it will be more than Monroe can use.
Their group, called Qualco Energy, plans to sign a contract with the PUD 
once it knows how much electricity its generator will produce, Reiner said.
Qualco Energy is a partnership between the farmers, the Tulalip Tribes and a 
local environmental group.

The group has contracted with a company to build a bio-digester and 
generator at the honor farm site, Reiner said. It has all the permits it 
needs, has loans and grants to get the project started and expects to start 
construction by the end of the year.
The group is simply waiting for Monroe to finish with its feasibility study, 
Reiner said. If the dryer option doesn't work for the city, then Qualco 
Energy will use the methane for generating electricity.

The utility is supportive of Qualco Energy.
"We value the fact that it is local," said Steve Klein, the PUD's general 
manager.
The PUD, currently considering a large investment in tidal energy, is 
looking for locally produced sources of renewable energy, Klein said. It's 
doing it to support
the county's fast-paced growth and because a new state law requires it do 
so.


Reporter Lukas Velush: 425-339-3449 or lvelush at heraldnet.com
http://www.heraldnet.com/stories/07/06/25/100loc_b1waste001.cfm