Technology for
plastic-to-diesel is new, untested
by Eiji Yamashita
HANFORD
- Seven pounds of waste plastics for a gallon of ultra low-sulfur
diesel. That's the concept Plastic Energy LLC touts with a
plastic-to-diesel conversion plant it wants to build near Hanford.
A conversion technology
called "catalytic cracking" is the key piece of the project, which
makes diesel out of plastics theoretically through a no-burn thermal
method.
Various literature indicates the technology is in use in Europe and
Asia, but the company says what it plans in Hanford will be a step
ahead of what already exists in the rest of the world.
But the fact that the
technology is new and untested has opened up a controversy,
eventually bringing the project to a halt.
With all the air
district permits, including the right to construct, taken away in
August, the company is trying to come up with a wholly new design
and plans. George Larson, a partner for the company, says the data
isn't there yet to prove the project's air emission safety but says
he's hopeful to have it by spring.
Opposition groups, led
by San Francisco-based Greenaction for Health and Environmental
Justice, say they won't trust a company which tried to build the
project without definitive air emission data for the first time
around.
Safety of the project,
as well as an approval procedure, was a main focus of discussion at
a public forum on the Plastic Energy project that was held locally
on Monday.
What's "catalytic
cracking"?
In its April 2004 draft
report "Life Cycle and Market Impact Assessment of Waste Conversion
Technologies," the California Integrated Waste Management Board
explains the technology in reference to Plastic Energy's plan and
discusses a market background.
Catalytic cracking is a
process that thermally converts discarded plastics into liquid and
gas fuels. Shredded plastic feed stock is melted and mixed with
catalyst, and gas is condensed and distilled into diesel and
gasoline. Gas and gasoline are combusted in a gas turbine to
generate heat and electricity, which makes the plant
self-sustainable.
It's a commercial
technology developed by H.SMARTech Inc., which formed Plastic
Energy. This method takes polyolefin, such as grocery bags and film
plastics, and rejects PVC, chlorinated plastic that releases dioxin
when incinerated.
H.SMARTech first
commercialized the process in 1998 in Zabrze, Poland, which by far
is the world's largest catalytic cracking plant. Australia-based
Ozmotech also has similar plants in Europe and Asia.
Can toxins fall through
the cracks?
Residents and green
activists point out a potential for harmful emissions from the
plant, and an absence of data adds to their frustration.
" We know that there's a
potential from any facility that deals with thermal process dealing
with plastics which are loaded with a variety of toxic materials to
have pollution," said Bradley Angel, executive director for
Greenaction.
There are many
pollutants that could possibly be incurred by a project involving
combustion like the Plastic Energy plant, most troubling of which,
an expert says, is dioxin.
" There's a bunch of
things you have to worry about, but the big thing you have to worry
about is dioxin. Why? Because dioxin is more carcinogenic than
plutonium," said Jane Williams, an executive director of California
Communities Against Toxics, of Kern County. Environmentalists often make a connection between dioxin and
incinerated PVC.
When he spoke in August,
Henry Dwyer, a manager of the company, repeatedly ruled out a
possibility of dioxin emission from the plant and said all PVCs will
be turned away.
PVC is No. 3 plastic,
which is non-recyclable. It is highly combustible and contains
chlorine, which poses pollution concerns when burned and released
into the air.
George Larson, a company
partner, acknowledged the plant may not be able to completely keep
out PVC but said it will have a safeguard against it.
" The front end
segregation will keep PVC out of our process, most of which are
recognizable white pipes ...," Larson said. "Certainly as has been
noted, some may get through. But on the distillation side of our
process, we have a dechlorinizer that will remove all chlorine from
any fuels that are produced."
It is in the company's
interest to keep PVC out of the feed stock because diesel fuel
contaminated with chlorine cannot be sold.
Responding to a concern,
the company also decided to burn gas from the Gas Company rather
than using gasoline byproduct from the process, Larson said.
" Some concerned
citizens said we don't have testing to confirm that gasoline which
we'll use does not have any chlorine in it," Larson said. "We will
submit a revised plan ... I do know for that section we'll use
utility grade natural gas to power the electrical system until such
time the necessary testing is done."
Is there emission at
all?
Other potential
pollutants incurred by the plastic treatment process are acid gases,
metal additives and VOCs, or volatile organic compounds, Williams
said. In August, Dwyer said the project is a closed-loop system with "zero
emission" during a conversion process.
But the draft assessment
report by the California Integrated Waste Management Board says the
technology creates emissions at various stages of the process.
" In addition to the
diesel and electricity products, the process will have combustion
emissions (criteria pollutants and toxics), VOC emissions from
organic storage and drying operations ..." the report says, while
noting that these emissions will be well below limits.
What the study concluded
The study evaluated the
operation of three conversion technologies, including catalytic
cracking, in terms of energy saving and air pollution.
Among the findings:
- Catalytic cracking
would end up in significant offset of sulfur oxide because of its
production of ultra low-sulfur fuel. But the report also noted that
"there is a higher level of uncertainty regarding air pollution
control requirements for [conversion technologies]."
- Data is insufficient
to assess the technologies' potentials for emissions of dioxins and
furans and other hazardous pollutants. When it comes to catalytic
cracking, the report found no test data on emission factors for
dioxins and furans, lead, cadmium, mercury and hydrochloric acid.
- Conversion
technologies seem to do better in controlling greenhouse gas than
landfills.
- They will reduce the
amount of needed landfill space and increase diversion rates.
- These technologies
will "likely result in greater local environmental burdens and a
potential reduction in regional or global burdens."
Question of being
"incidental"
Kings County Planning
Agency Director Bill Zumwalt approved a one-year extension of a site
plan review for the Plastic Energy project last month.
Concerned residents do
not like the fact that this project gets excused from a much closer
scrutiny involving an environmental impact report and a public
hearing.
Zumwalt says site plan
approved projects are exempt from such a review because they satisfy
the general plan and zoning ordinances that already meet the state
environmental requirement.
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