Emission Control
American Environmental
Fabrication & Supply, LLC
Natural Gas Conditioning
Gas Separation Systems
VOC Biofiltration Systems
Granulated Carbon Systems
VOC Concentrators
Automated PLC Controls
Equipment Inspections - Installation - Rebuilds
Low NOx Burners
PSA Systems
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Benefits of Renting vs. Owning Air Pollution Control Equipment
We have a ready to use air pollution control fleet or can design a specialized system for your plant operations. Some of the available systems include:
Granulated Activated Carbon (GAC) Systems, Biological Oxidation Systems, Wet Scrubbers, Regenerative, Catalytic and Direct Fired
Thermal Oxidizers
. Rentals range from 6 months to 5 years with flexible options.
Purchasing the Correct Air Pollution Control Technology
There are many various types of VOC control technologies in today’s market, but most of them may
not be the correct equipment for your application. Knowing the various principals behind each of the
technologies will help you choose the technology that’s right for your waste-gas application. As Global
concerns are increasing at a rapid pace, and with
more pressure being placed on governmental
authorities to create and enforce regulations
that often require higher destruction rates
and improved capture procedures of air pollutants many industries around the world and
air
pollution control equipment manufacturers are developing new more advanced
technologies
to meet these growing domestic and international regulations while providing
improvements in air pollution control investment and the associated operating costs.

A diversity of pollution control equipment is currently available, but many manufactures fail at many
technologies and have themselves trapped into splitting technologies into separate equipment.
Pioneering technologies and system controls are now available to modify the basic emission
equipment arrangement and create many distinct types of air pollution control technologies.

Biological Oxidation

AEFS has pioneered Biological Oxidation as a method of destroying unwanted hydrocarbons with
the use of bacteria which are specifically designed to digest the unwanted hydrocarbon structures
emitted in the off-gas process. The bacteria may be designed to work in conjunction with a granulated
carbon system to produce very high destruction efficiencies. These efficiencies are >99%. The major
benefit of a Biological Oxidation system is the reduction in operating costs such as fuel and
electricity. The maintenance on this type of equipment is reduced due to fewer operating parts and
insurance is also reduced over normal thermal oxidation equipment due to the inability of the
equipment to generate a explosion. Although, this technology is not a panacea to all off-gas emission
control it has a very high value to HAP and VOC compound remediation on most industrial
applications.

Thermal Oxidation

These applications are most often used to convert organic hydrocarbons into carbon dioxide
(CO2) and water (H2O). By increasing the temperature of the waste-gas process stream, breaking of
the hydrogen-carbon bonds occurs. This process allows new bonds to be created such as CO2 and
H2O.

Closed thermal oxidizers characteristically are designed with a 1 second or greater total residence
time. Residence chamber time is the time the waste process stream is contained within the heated
area and is critical for proper mixing. Often oxidizer designs fail to complete the proper mixing
in the retention time frame and additional fuel must be burned to meet the permitted values.

Regenerative Thermal Oxidizer

Regenerative systems are thermal oxidizers that operate at temperatures between 1400°F to 2,300°F.
These systems use structured ceramic stoneware or other heat exchange media to retain the
generated thermal energy. In most designs, the media is mounted in vertical or horizontal columns.
The process air stream is passed through a column of ceramic media as it enters the regenerative
thermal oxidizer.
The waste-stream is heated to the oxidation temperature within the combustion chamber and if the process stream doesn't have ample VOC's a burner assists in bringing sufficient temperature to the
combustion chamber.

Typical temperatures of VOC waste streams of hydrocarbons range from 1400°F to 1600°F, however higher temperatures and retention times are required for halogenated hydrocarbons 1800°F
to 2200°F. The waste air stream then exits the oxidizer through a second media column. The second column maintains or stores energy from the hot air stream.
By continued valve cycling the waste-
gas air stream switches between the heat sink columns or heat recovery beds
, by this process the incoming air stream is heated by the heat sink media, which in the previous cycle accepted the
heat from the waste-gas air stream exiting the combustion chamber.

When the heat recovery bed starts to lose radiant heat to the incoming air stream, the valves cycle and becomes the switched heat recovery bed becomes the acceptor of energy or
heat
, continued repeating of the valve cycle assures minimum heat loss. For greater heat retention within the heat recovery chambers the valve cycle rate is increased. The principle is simple and
proven.

Regenerative Thermal Oxidizers can be designed with more than two heat recovery beds or columns. Some of the regenerative equipment characteristics are moderate capital equipment costs
with high thermal efficiency
. Destruction is high typically 98%-99% with lower energy costs. Loss through radiation is slightly higher due to the large surface area, however radiant heat loss can be
controlled by the use of high density 12lb. or higher ceramic fiber insulation. Most applications include lower VOC levels with higher waste-gas flows.
Systems can be skid mounted for quick and
effective installation, start-up and training times
.

RTO systems have materialized as the leading air pollution control technology because of their very high heat recovery, which produces an outstanding operating cost advantage in
comparison to other technologies while
maintaining high flexibility for many types of waste gas processes. Typically these systems are larger, requiring greater installation work, unless the system is
skid mounted.

Regenerative Catalytic Oxidizers

Regenerative catalytic oxidizers are similar in design to the regenerative thermal oxidizer. The addition of catalyst media to either the center of the media or the top of the media beds allows
lower operating temperatures 400F to 800F
. Depending on component design, Regenerative Catalytic Systems may also can be operated as a Regenerative Thermal Oxidizer after catalyst
degradation.

Systems have
small or no NOx formation, very low operating costs with high thermal efficiency. Caution must be used not to foul or plug the catalyst heat bed and more stringent PLC control
must be used. These systems have
higher capital costs due to the metallic catalytic media but reduce the energy consumption up to 50%.

Catalytic Oxidizers

Catalytic oxidizers are alternatives to other high temperature thermal oxidizers. These systems oxidize waste gas streams into carbon dioxide and water. Their successful operation is limited to a more
controlled range of applications
. But, catalytic oxidizing systems offer considerably lower fuel consumption, operating costs and lower CO and NOx emissions. The two essential parts of the
equipment are; pre-heat section which is designed to achieve a temperature uniformity of the preheated waste stream, and the catalyst bed, where the greater part of the oxidation reaction takes place.
The
oxidation of most hydrocarbons with the catalysts occurs very quickly in the range of 400-900F.

Catalytic oxidizers are
restricted to applications in which the waste stream has lower particulate loading or “media poisons” which can cause reductions in the effectiveness of the catalyst.
Typical poisons are principally
silicon and phosphorus, which cover the catalyst; halogens and sulfur harm the active metal coating may reduce the activity of some catalysts. Attrition, deposition,
coking can cause the media surface to become damaged and replacement is necessary.
Regenerative Thermal Oxidizer 80,000 cfm
Filtercrobe Granulated Activated Carbon System
ReGen Series Regenerative Thermal Oxidizer 25,000 cfm
Granulated Activated Carbon Canisters 100-2000 cfm
Thermal Swing Adsoprtion System
Toll Free: +1 (866) 467 - 9374
Main: +1 (918) 708-1253
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VOC Concentrators - Thermal Swing Regeneration Adsorption
Concentrators are used as an emission control device to allow higher volumes of waste gas to be collected on an adsorbent for future destruction. Concentrators allow the lower concentrated VOC's to
be collected and then exhausted at smaller volumes at higher concentration levels. Generally, concentration levels are operated around ten times the waste gas concentration, but this value may be
increased depending on the application. Therefore by using a concentrator many thermal oxidizer systems are allowed to operate without or with minimal amounts of auxiliary fuel. Concentrators
reduce the operating cost by loading the VOC's at a higher concentration. The concentrated volume from the VOC Concentrator reduces the size of the oxidation equipment.

VOC's in the waste gas stream are first processed into one of the adsorption units (two are usually used, but any number above two may be used), while one of the adsorption beds is being thermally
regenerated. Hot air flows into the adsorption unit; this process heats the captured VOC's and thus desorption or boiling off the VOC's occurs. The condensed VOC vapor may now be processed to the
thermal oxidizer for thermal destruction at a higher concentration rate, lower flow rate and higher inlet temperatures. This process reduces the amount of auxiliary fuel required to sustain the set point
destruction temperature of the system.

After the VOC are released, cooling air from a blower is admitted in place of the heated air. When the adsorbent has cooled to ambient conditions, the “conditioned” adsorption capacity has been
restored, and the adsorption bed is now considered regenerated. Regeneration equipment may be designed to occur between one and eight hours depending on the size of adsorption equipment.

Granulated Activated Carbon Systems

Granulated Activated Carbon Systems or  vapor phase VOC canisters are designed for a economical cost effective approach to air or vapor treatment for short or long term emission applications.
Systems generally contain all of the necessary requirements for use as an effective VOC emissions control system for air or
vapor phase process treatment applications.

All
GAC Systems include a secure carbon bed support across the entire canister lower sectional area which creates a plenum region below the support area for proper inlet distribution across the
carbon bed. These carbon canisters are generally constructed of
unlined carbon steel or T304 stainless steel, angle iron supports are used to support the perforated screens used with the
granulated activated carbon during air treatment. Most GAC vapor phase carbon adsorption canisters are designed for
treatment up from 10 to 2000 cfm, but may be designed for larger applications
The vapor phase GAC adsorption units provided a wide variety of vapor phase activated carbon products that can be specific for your air or vapor treatment application. These systems provide a very
low cost, effective method of  treating small quantities of vapor phase VOC's.

VOC Air Stripping - Tray Aeration Treatment

Contaminated VOC water is generally pumped into an inlet chamber where it flows over distribution weirs and along the aeration trays located inside the air stripper unit. The filtered ambient air from
outside the stripper unit is blown into the fluid process with sufficient pressure to push the filtered air up through the aeration holes located on the aeration trays. As the air flows upward through the
water, bubbles are created which forms froth. This
froth increases the surface area of the treatment water which allows mass transfer of the VOC contaminates from the water to the
exhaust stream
. The stripped off gas and air continues upward and is blown out the top of the air stripper unit for discharge to an additional post treatment device, the finished water flows down to the
bottom of the air stripper unit where it is
collected and pumped to the waste water distribution system.

Operation of the aeration tray system also may cause oxidation of metals and formation of scaling from the water hardness. The concentration of this depends on the water supplied to the air
treatment system. Once formed, the metals formation and scaling eventually cause fouling of the trays and require periodic cleaning.
Periodic cleaning of the trays is accomplished by accessing
ports on the system with a washing wand or high-pressure washer
. More thorough cleaning requires that the trays be removed completely. Spare trays can be provided to allow continued
operation during cleaning.

Solvent Recovery Systems

Adsorption technology is the physical attachment of VOC ions and molecules onto the surface of another. The essential principle of adsorption when pertaining to plant waste gas emission
control is when the volatile organic compound within the process air stream passes through a bed of very
high surface area solid which usually consist of the following materials; activated carbon,
silica gel, or molecular sieve material
.

Once the empty spaces within the adsorption material are filled with VOC's to capacity, the waste gas process stream is then diverted to a second adsorption container while the original container
removes the VOC bonding by passing high pressure stream or by raising the temperature within the adsorption container by thermal induction releasing highly concentrated VOC's. The highly
concentrated volatile organic compounds within the air stream passes through a condenser and a distillation column whereby it is separated and recovered.
Alternative solutions to applying use of a
condenser and distillation column is to exhaust the saturated VOC's to a thermal oxidizer during non-peak times.

Higher investment capital is required with moderate energy cost. Destruction efficiencies range from 95-98% with higher maintenance costs from replacement or regeneration of
adsorption material. Additional distillation is necessary to separate several solvents with the potential to reuse or sell the solvent.

Right Technology For The Operation

Which one of the listed technologies may best be applied for your application?  Your answer can be difficult depending on the method you take in the evaluation process. The best approach is to find
Most vendors will offer a free evaluation to assist you. Some of the information that is required to make the right decision are listed below:

A.        Total number of emitting sources
B.        Annual hours for each of the emitting sources
C.        Flow rate from each source, SCFM or M3
D.        Total (lb/hr or kg/hr) of VOC material from each listed source
E.        Composition of the process stream (VOC's, particulate matter, silicon)
F.        Energy costs (Electric, Natural Gas)
G.        Regulatory requirements for your facility

After collection of the data, a request for quotation (RFQ) can be sent to selected vendors. A vendor should have the appropriate technologies in its product mix and is willing to stand behind their
equipment.

Guidelines For A Correct Equipment Purchase

When evaluating the options, include operating, installation, training, plant control, and equipment capital costs. Capital and operating costs should be based on the actual utility costs,
operational times and annual operating schedules of the plant.

Request a production schedule for the system to ensure that the facility can meet any of your regulatory requirements.

Working with proper data, applying utility costs, facility limitations, regulatory requirements and plant operating schedules all comprise important roles in determining the correct abatement equipment.
Working with a vendor can greatly assist in making the right product choice.


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Implement proven equipment designs with
chemical, thermal and biological reactions
that achieves the required process result.
Results shall be based on reaction rates
and proper control logic.
Our Corporate goal is to implement the
correct design criteria with the use of
proper metals, instruments and controls to
achieve the required result with the least
amount of maintenance and associated
energy costs.
before it leaves the plant. It is our way of
knowing that you are receiving correctly
designed equipment to meet your specific
needs.