[Digestion] Digesting MSW....Brunswick, Maine's 'single bag' system.

[Katahdin Energy Works]

Our town already sorts out MSW; and in fact is a leader in New England for
this.

The way it was done was by forcing people to pay a per bag charge...we have
to buy an 'official' plastic bag or it won't be picked up.

We have several streams--the Bags which can have anything in them, other
than a list of hazardous stuff; newsprint and paper; plastics--not all, but
most, and metal.

The result are three containers on the sidewalk every Wed.  Leaves and grass
and tree trimmings are taken to the landfill; as are bulky items and those
for which we pay a disposal fee, like tires and batteries. Organics now go
into a household composter--and I haven't yet seen any discussion of a
neighborhood AD, so whose backyard will we use?

The town has contracted curbside pickup to a large and rapidly growing
conglomerate run by the CASELLA family--http://www.casella.com/.  They have
invested a considerable amount of money in a new facility in Massachusetts
which take the 'official' bags, burst them, and then sort out the innards
using both mechanical and human mechanisms.

I toured the facility back  in April only a few months after it opened and
was fascinated over the workings of various mechanical and optical sorting
'stations'; and the immense problem of plastic bags gumming up the
works---they were wrapped around everything. 

Most of the cost of the bags goes towards the contract with CASSELLA/PINE
TREE WASTE, who claims that the revenue from the sale of recovered
materials---most, if not all, are bailed and shipped to Asia; doesn't cover
the cost of the facility.

This is the wave of the future in municipal waste processing along with
regional toxic waste disposal facilities.

 Taxpayer resistance to paying twice to dispose of their refuse isn't enough
to stop the contracts. Towns now can close their nearly filled landfills;
and don't have to bear the consequences of injury to municipal
employees--Nearly all the people at the Casella facility spoke fluent
Spanish, raising questions about use of illegal's, nor did the Part Time
hires have health insurance, etc

 This move is a win-win for the towns and confirmation of the rule governing
MSW....out of sight; out of mind!; and the rule of American Capitalism that
making a big risky investment may just result in a profitable monopoly. 

It's quite a tour being on the inside of a giant, noisy, machine which sorts
out all the stuff in MSW, leaving piles at the bottom for bailing or hauling
out in bins, i.e. mixed glass. 

Btw...the plastic bag problem is being addressed by the two
conglomerates--SHAWS & HANNEFORDS, with the sale of sturdy shopping bags
that are used over and over again--if you remember to take them with you;
and a resurgence of paper bags!  Styrofoam packaging is now the focus. 

Frank.

Frank J. Heller, MPA
KATAHDIN ENERGY WORKS
12 Belmont St.
Brunswick, ME 04011-3004
207.729.6090
http://mysite.verizon.net/fjheller/


-----Original Message-----
From: digestion-bounces at listserv.repp.org
[mailto:digestion-bounces at listserv.repp.org] On Behalf Of Jim and Amy Rankin
Sent: Thursday, October 11, 2007 12:42 PM
To: Zietsman, Rex; digestion at listserv.repp.org
Subject: Re: [Digestion] Digesting MSW

Rex,
This ambitious technique to process unsorted MSW as you describe it sounds 
as if it would work well in conjunction with a sewerage treatment plant in 
several of the stages

The water bath might use water from some stage of the sewerage treatment 
plant and the same digesters might be used for the sludges and the 
supernatant that are used for the sewerage.  In effect the organic fraction 
of the MSW could be used to enrich the sewerage for increased gas production

and increased reactor efficiency.  The aerobic stages that are commonly used

in sewerage treatment plants could be used in a secondary role to polish the

digester effluent instead of the primary treatment of sewerage supernatant 
directly.

Couple the recycling of glass and  metal, the digestion of organics and 
incineration or recycling of the plastics and it would seem possible to 
almost completely eliminate the MSW stream to be lanfilled.

Maybe this already exists?

Jim

James R Rankin, DVM
Cedarcrest Farms, Inc
Faunsdale, AL USA


>
> There is an Israeli technology that takes unsorted MSW, sorts the
> "heavies" from the "lights" by dropping the MSW into a water bath -> the
> plastics float off while the heavies are sucked out and subjected metal
> and glass recovery. The organics are broken up by shear in the water
> bath using water jets. The organic laden water is then sent to a two
> stage AD process of which the second stage is a UASB treating filtered
> water from the first stage. This system works remarkably well but, as
> you noted, does not generate as much energy (plastics are not burnt and
> the co-production of CO2 leads to energy loss).
>
> For more information, contact Mel Finstein: see contact details below
>
> Kind regards
> Rex
>


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