Clearing the air

eNeRGy SWITCHING
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Clearing the air
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Innovative pol ution control technology
al ows CMPC’s Talagante tissue mil to
replace natural gas with cheaper fuel
Paul a. TeTley
Rapid industrial and urban growth in higher levels of pollution
Santiago, Chile, has not been without
compared with natural gas,
its price: pollution from fine suspended
and Thermal Engineering
particulates represents a major health
realized that any alterna-
concern. For that reason, heavy indus-
tive fuel solution would also call for installation
This unique
trial facilities operating in the capital
of the proper environmental controls at its client’s
combination dust
city must comply with demanding requirements in
facility.
collector/SO2
terms of emissions and particulate exhaust.
Because of the low cost and ready availability
scrubber environ-
Meeting the air-quality regulations became
of #6 fuel oil, Thermal Engineering felt it was a
mental control
especially challenging for one local pollution
choice that made good business sense, although
system allows
control systems integrator, Thermal Engi-
its use would require strict environmental reme-
CMPC, a major
neering, when faced with the loss of a primary
dial measures. Byproducts of burning the fuel in-
paper manufac-
source of clean energy for the Talagante mill of
clude a high level of particulates as well as SO2 gas.
turer in Santiago,
CMPC—considered the second-largest tissue
Chilean environmental regulations call for tight
Chile, to use low-
manufacturer in Latin America—that was using
controls of these pollutants, with removal of all
cost #6 fuel oil in
natural gas from Argentina. The solution turned
atmospheric emission particulates and reduction
full compliance
out to be not only environmentally friendly, but
of SO2 to undetectable levels.
with government
also economically sound.
According to Arnulfo Oelker, president of
pollution abate-
Thermal Engineering, “Here in Santiago, we
ment standards.
SEARCHING FOR A SOLUTION
have emission restrictions that wouldn’t allow
CMPC already has an enviable record with regard
using heavy fuel oil if you don’t use a filter to
to environmental protection and compliance
reduce particulate emissions and a scrubber to
policies and had begun working toward removing
reduce SO2 emissions, because of the high sulfur
sulfur dioxide (SO2) gas and particulate matter
content of these kinds of fuels.”
(PM ) even before many Chilean environmental
To solve this problem, Oelker sought a total
10
regulations were enacted.
system solution, working closely with Met-Pro
The company had used clean-burning natural
Corp., a U.S. company that owns divisions and
gas to fuel its plant and manufacturing processes.
subsidiaries throughout the world involved in
But natural gas supply is declining, particularly in
pollution control, product recovery, and fluid
Chile and near the paper mill. And when a com-
handling products and systems. This synergis-
modity is in short supply, its price rises in propor-
tic relationship among the company’s divisions
tion. As a result, the paper mill had relied upon
enabled two of them—Flex-Kleen and Duall—to
gas sources within neighboring Argentina. As that
work together to design a unique system for the
supply became less predictable, to the point of
paper manufacturer.
putting production at risk, CMPC looked for help
with regard to use of an alternative fuel that would
MAKING THE SWITCH
also comply with appropriate pollution abatement
Thermal Engineering’s answer to the natural gas
standards. Other forms of fuel tend to burn with
shortage consisted of a switch to #6 fuel oil and
Paper360º? ? October 2008
21

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eNeRGy SWITCHING
In the case of the paper mill, the
filter bags must also accommodate
the moisture that is produced with
SO2 as part of burning #6 fuel oil,
while still providing full filtering
capability for the particulate emis-
sions. To meet the paper mill’s and
the government’s requirements,
special filter media were designed
to withstand the harsh process-
ing environment it is subjected to;
it also had to provide a long, use-
ful lifetime to minimize process
Figure 1
downtime. The SO2 present in the
the installation of an environmental control sys-
exhaust gases along with moisture, is removed by
tem consisting of a combination dust collector and
the filter media prior to atmospheric exhaust, and
SO2 scrubber (Figure 1). The system, the only one
the filter media must withstand the high acidic
of its kind in Chile, allows the company to burn #6
content of the exhaust emission while still provid-
fuel oil in its manufacturing processes while still
ing the highest possible efficiency and useful life
maintaining particulate and SO2 emission levels
characteristics.
well within government regulations. It also per-
The price of natural gas has risen steadily
mits operation with #6 fuel oil without any perfor-
and significantly since the installation. As Oel-
mance loss and significantly lower costs than nat-
ker points out, “Even if our client had natural
ural gas while SO2 remains almost undetectable.
gas available to them, they would use heavy
Innovative technologies have helped make
fuel oil, which is more convenient for them and,
the job of environmental compliance, especially
right now, about 25% cheaper than natural gas.
for challenging requirements such as particulate
In practical terms, natural gas ceased to be an
filtering from #6 fuel oil emissions, significantly
option.”
more efficient. For example, one system compo-
Of course, while the cost of #6 fuel oil may
nent includes an option for the system’s pulse jet
be less than that of natural gas for similar energy
collectors that permits top bag removal (compared
usage, the cost of the environmental-control equip-
with standard bottom bag removal approaches).
ment must be included when considering an alter-
The top bag design makes leaky or full filter bags
native fuel source. On the other hand, “the Met-
more apparent and easier to maintain, with bag
Pro/Duall/Flex-Kleen system provided a return on
changes possible in a matter of seconds. Tools
investment within only three or four months—an
and/or clamps are not required to swap bags.
unprecedented situation,” Oelker says.
The lower-cost fuel approach and its sup-
porting environmental-control systems have
Environmental control in Chile
been in place for a year-and-a-half at the paper
mill with no operational problems and with gas
One of the fastest-growing economies in Latin America since
and particulate emissions maintained well
the early 1990s, Chile has seen a corresponding growth in
within government compliance limits. As an
its factories and in vehicular traffic, especially in and around
added bonus, the ash rejects from the process
Santiago. About 40% of the country’s people live there, and,
are reused as an energy source by an indepen-
because its air quality ranks among the worst of the world’s
dent, non-related company, and the wastewater
major cities, Santiago’s urban population suffers a high rate of
from the system’s wet scrubber is treated on-site
respiratory problems, especially among children and the elderly.
Environmental control in Chile is driven largely by the Special
in full compliance with Chilean environmental
Decontamination Commission for the Metropolitan Region
regulations.
of Santiago. The commission is responsible for controlling
and eliminating air contamination by increased monitoring of
Paul A. Tetley is executive vice president of
air quality, setting specific air pollution reduction goals, and
Met-Pro Corp., Harleysville, PA. Contact him at
through regulatory enforcement.
ptetley@strobicair.com or +1 215 723-4700.
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Paper360º? ? October 2008

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