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THE COMPANY
BASF is the acronym for BADISCHE
ANILIN UND SODA FABRIK, a company founded in Germany
in 1865. A pioneer in the manufacture of dyes and coloring
agents, it currently has 350 subsidiaries in 35 countries,
producing a wide range of chemical products. BASF has
customers in 160 countries and approximately 120,000 employees
on five continents.
The company first arrived
in Venezuela in 1948, with imported fertilizer products.
In 1967 it became incorporated as BASF Venezolana S.A.,
beginning operations in 1970. In 1972 it produced the
first polymeric dispersions and solutions; in 1986 it
began production of vitamin and mineral premixes for animal
feeds; and in 1991 it opened one of the most modern styrene-butadiene
dispersion plants in Latin America and expanded its production
capacity for acrylic dispersions.
BASF Venezolana S.A. manufactures
approximately 80 chemical products: acrylic polymeric
and styrene-butadiene dispersions for the adhesive, paper,
construction, paint, and textile markets, among others;
supplementary products for paper, leather, textiles, and
cosmetics; copolymers for the detergent manufacturing
industry; and pigment preparations for leather, textiles,
and special chemicals. The animal feed plant produces
58 premix formulations.
The company has an industrial plant in Turmero, Aragua,
and a business office in Caracas. It currently employs
206 direct and indirect workers, and is number three among
the group’s affiliates in Latin America, after Brazil
and Mexico. The Turmero plant is in the Güere Industrial
Area and occupies an area of 16.1 hectares , 30% of which
is occupied by manufacturing facilities, 5% by environmental
control facilities, and the remaining 65% by landscaped
area.
CURRENT
SITUATION
Business activities at BASF
Venezolana S.A. focus on the production of marketable
goods. In the process, wastes are also generated that
have no apparent use but possess a wide range of compositions
and physical features.
To prevent environmental pollution
and protect personnel from improper waste handling, the
company developed a Comprehensive Waste-Handling Program.
This program is mandatory and was created under corporate
headquarters guidelines and in accordance with the country’s
legislation on waste.
From 1990 to 1996, a Michaelis
Cd-9s incinerator furnace was used to incinerate solid
waste, packing material, and other solid organic wastes.
The Michaelis furnace operates with a main fixed-bed incineration
chamber with a working temperature between 800 and 900°C,
and an afterburner chamber for gases whose temperature
reaches up to 1000°C. Both chambers use fuel oil burners
with an average consumption rate of 25 kilograms per hour
each. This equipment has a cyclone scrubber array for
retaining dust before it goes out the stack. Incineration
gases are mixed with cold air to lower exit temperature
to 220°C. The total amount of gases emitted is approximately
6,000 cubic meters per hour.
Because
of its simple design, this furnace is not fully adequate
for all the different types of wastes that are generated
in the chemical industry. For example, the furnace does
not enable proper intake of spongy wastes, nor does it
have any kind of device for stoking or agitating to improve
the burning of the wastes being incinerated. The latter
problem was what caused this equipment finally to go out
of service, because the bottom layers of waste that were
in direct contact with the refractory furnace floor did
not receive any oxygen for combustion nor any direct flame
from the burner, but they did receive conducted heat.
This resulted in such a violent concentration of gases
that an intense fire erupted inside the equipment and
caused serious damage to the refractory lining.
Due
to the fact that this failure actually occurred inside
the equipment, no personnel were injured, nor were other
facilities damaged. Experts from corporate headquarters
reviewed the incident and recommended that the equipment
not be repaired because its technology was considered
unsafe, its energy consumption was high, and it emissions
generation had high pollution potential.
STRATEGY
Replacement
of Michaelis Incinerator Furnace
In
a search for an alternative for treating waste, BASF Venezolana
S.A. did research on a nationwide scale and discovered
that no technology existed that enabled it to be properly
treated. The company then decided to invest in a new incinerator
furnace whose design was safer from the environmental
and operational points of view, and which would operate
with natural gas.
In
this replacement effort, BASF Venezolana S.A. contracted
with the U.S. company RMT / Four Nines – ETSI to select
the best alternative. After reviewing the features of
plant wastes, they recommended replacing the existing
Michaelis furnace with the following types of furnaces:
-
-
Fluidized
Bed Incinerator
-
Technical
and financial proposals were requested from companies
recognized worldwide in the manufacture of incinerators.
The alternative selected and supported by corporate headquarters
was submitted by the HAFNER GmbH company, which proposed
equipment (the HAFNER Incinerator Furnace) that complied
with all the specifications required for incineration
of all the different types of wastes from BASF Venezolana
S.A. This equipment not only complies with the strictest
environmental requirements for atmospheric emissions but
has the significant advantage of being modular—that is,
further process units may be added on to it.
HAFNER
Incinerator Furnace
The
Michaelis furnace was replaced by a HAFNER, which is a
rotary furnace with the following design criteria:
1)
Normal features of wastes considered by equipment design:
Normal
Waste Features
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Heating Capacity
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11,900 kJ/kg
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Combustible Content
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60%
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Water Content
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30%
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Inert Material Content
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10%
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Carbon Content
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54.7%
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Hydrogen Content
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6.8%
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Oxygen Content
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35.8%
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Nitrogen Content
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0.7%
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Sulfur Content
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1%
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Chlorine Content
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1%
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Source: BASF Venezolana S.A.
2)
Air requirement for incineration: 2,097 nm3/h
3)
Dry gas exiting furnace:
Composition
of Dry Gas Exiting Furnace (kg/h)
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Nitrogen
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2,083
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Oxygen
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328
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Carbon Dioxide
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361
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Total Dry
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2,773
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Source: BASF Venezolana S.A.
4)
Total gas exiting furnace: 2,407 nm3/h
The
HAFNER furnace’s main advantage is its great flexibility
in handling the types and amounts of wastes that need
to be eliminated. It enables higher incineration temperatures
and longer contact times for incinerated wastes and gases.
Because it is a rotary furnace, it can ensure complete
burning of high organic content wastes, which are rendered
inert. It can also be simultaneously fed with liquid,
solid, and spongy wastes.
In
achieving complete, safe destruction of wastes through
burning, a large amount of oxygen is supplied and the
natural gas burner is kept on at all times. Slag and gases
are removed through an outlet from the rotary furnace.
Following is a description of the way this HAFNER rotary
furnace operates:
1)
Intake System. This system breaks up solid waste into
smaller pieces, which then fall into a concrete pit. A
hydraulic claw then picks up the waste in portions and
transfers them to the waste intake hopper tray, which
is directly connected to the furnace.
2)
Liquid Injection System. Liquid injection is performed
at both the first and second chambers. Wastes with low
flammability are injected into the first chamber, and
highly flammable wastes into the second chamber. This
system was built by the Maintenance Department of BASF
Venezolana S.A.
3)
Ash Removal System. Solid inert material remaining
from the incineration process is conveyed to the bottom
of the furnace and from there to a conveyer belt system.
Slag or dry ash is picked up and packed in labeled drums
for moving to storage.
4)
Afterburner Chamber. Organic gas components generated
during the incineration of waste in the rotary furnace
have high stability when heated and therefore require
special conditions so that they can be converted into
simpler molecular forms such as CO2, H2O,
SO2, NOx, and CO. The afterburner chamber enables
an oxidation efficiency of up to 99.99% for organic gas
components, due to the fact that it has an efficient system
for supplying air, and provides turbulence, higher temperatures,
and longer contact times.
5)
Particulate Filter. Hot gases with inert solid particles
exiting the afterburner chamber are mixed with ambient
air to bring their temperature down to approximately 200ºC,
then are sent to the scrubber, where solid particulates
are removed.
6)
Gas Emissions Stack. The gas outlet stack is cylindrical
and galvanized, and has protection against abrasion and
heat. Clean gases are released into the atmosphere at
a temperature of about 200°C, at a rate of 24 meters per
second.
7)
Emergency Relief. This is a pneumatic gate that opens
if there are any breakdowns, power outages, or excess
pressure, in order to avoid excessive accumulations of
gases and the danger of equipment explosion.
In
addition to technical advantages and operational safety,
the HAFNER incinerator furnace also provides outstanding
environmental benefits. It generates emissions that are
less polluting because its two burners operate on natural
gas. Wastes are also subjected to longer burning times
and higher burning temperatures, all of which result in
efficient destruction of wastes by incineration.
Due
to the composition of natural gas, combustion is cleaner
than with the use of fuel oil. For this reason, pollution
by emissions generated by the HAFNER furnace is substantially
less than for the Michaelis furnace. The following table
illustrates some of the advantages of the HAFNER furnace.
Comparison
of Michaelis and HAFNER Furnaces
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Furnace
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Fuel
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Usage
(m3/mo)
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Fuel Cost (U.S.$/mo)
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Maximum Emissions of SO2*
(mg/m3)
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Michaelis
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Fuel Oil
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36
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3,941
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84.5
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HAFNER
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Natural Gas
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50,000
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1,634
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0
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*Maximum
concentration of SO2 at outlet, when wastes
containing sulfur are being burned
OUTLOOK
BASF
Venezolana S.A. is now developing the second phase of
its HAFNER incinerator furnace project. In this stage,
equipment for continuous measurement of gases exiting
the furnace will be added, which will enable greater control
of emissions to the atmosphere, thus contributing to the
reduction of greenhouse effect gases. In a third stage
of the project, improvements will be made to the system
for the intake and treatment of gases in order to produce
even cleaner emissions.
CONCLUSIONS
The
practice of incineration does provide one solution to
the industrial waste-handling problem, but it also generates
potentially contaminating gases that, when not efficiently
handled, can contribute to air pollution. The technical
features of the HAFNER incinerator furnaces are providing
direct benefits through efficient waste destruction, greater
operating safety for workers, and improved quality of
the emissions that are generated.
BASF
Venezolana S.A. has made a significant investment in this
engineering effort, with very satisfying environmental
and safety results for its personnel. This, in turn, is
encouraging the company to continue improving its environmental
performance and to invest in new projects to comply with
the strictest environmental requirements in the market.
CONTACT
Zoraida
Torrealba de Rodríguez
Chief,
Department of Comprehensive Safety and Laboratories
BASF
Venezolana S.A.
Avenida
Principal de la Urbanización Industrial Güere
Sector La Julia
Turmero,
Aragua, Venezuela
Tel.
(58-2) 205 9560 / 205 9696
Fax
(58-2) 205 9491
E-mail:
zoraida.torrealba@basf-ven.com.ve
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