METHODS OF GOC ODOR CONTROL
There are three (3) primary methods of odor treatment available from
GOC Technologies.
The first method is by Air Contact. This is the atomization of reactants and deodorizers into the same air currents that are carrying
the odorous gases, enabling a reaction between the molecules of the odorous gas or gases and the deodorizer upon contact in the atmosphere.
The second is by Surface Contact. This is the spraying or misting of a solid or liquid surface with reactants and deodorizers to generate
reactions near or on that surface. This method treats the molecules as or just before they enter the gaseous or "vapor" state. The
third method is by Incorporation. This is the addition of a substance or substances into a substrate in order to change the underlying
reactions causing the odorous compounds to occur. This method reduces or eliminates the quantity of odor to be treated by air or surface
contact.
Products which operate through air contact must be misted, atomized, fogged, or otherwise initiated into
the air containing the offensive gases. This may be in either indoor or outdoor situations, and requires
corresponding equipment and
technology depending on the exact situation. As the term "air contact"
implies, these products work by coming into physical contact
with the molecules of the odor in the
atmosphere. Consequently, the product must be introduced in a form that allows its molecules
to travel
wherever the odor molecules are traveling. The product particles must be small enough and light enough
to stay in the air
so that the odds of their coming into contact with the odorous molecules are increased.
In general, GOC prefers atomization
systems instead of fogging or misting due to the smaller size and
lower weight of the atomized particles. The nozzles we recommend
and sell expend less than 1 gallon
of total fluid per hour at continuous operation. Some atomize only one half gallon per hour. There
are
certain situations which require high volume while retaining small particle size. We utilize special air
powered nozzles with
capacities up to 6 gallons per hour and more for these situations. We recommend
low pressure hydraulic systems for outdoor use or
use in very large indoor areas, and compressed air
systems for indoor use in smaller applications, exhaust stacks, or in any situation
where total
introduced moisture is an issue.
Control devices for these systems allow continuous or intermittent operation
depending on the needs of the particular situation. Examples of situations for hydraulic systems include perimeters of landfills,
the
mixing or turning areas of compost sites, large transfer station floors, and feedlots. Examples of situations
for compressed air
systems include smaller transfer stations, pressing rooms in wastewater treatment
plants and paper mills, garbage rooms or compactor
areas in buildings and hotels, and even restrooms.
In some applications, deodorization equipment may be attached to existing equipment
and/or vehicles.
This is especially true at landfill and compost sites.
Some situations offer very few alternatives other than
air contact treatment. This may be for physical
reasons, process reasons, or economic reasons. Other sites may be treatable in more
than one way,
or they may require a combination of treatments. In some situations, a perimeter air contact
(atomization) system is
installed as an emergency fall-back treatment for use only when other systems
fail to contain odors or cannot keep up with odor generation.
For example, a transfer station that normally
utilizes topical treatment of the receiving floor and incoming wastes might maintain
an atomizing system
over doors or near a perimeter as an emergency measure in conditions of high heat and humidity, or
when an extremely
odorous load arrives.
Surface contact products are designed to work topically on odor producing substrates. They
can be
utilized on liquid or solid surfaces, and primarily work in one of two ways. They may form a crust or
surface seal or barrier
to keep gases in, or they may form an area of increased biological or chemical
activity at the surface which limits or changes the
reactions occurring and thus changes the types and
quantity of gases formed and emitted. Surface contact products may be applied using
hand-held or
pressurized sprayers, or they may be applied with overhead nozzle systems, or attached to existing
equipment. In exact
opposition to air contact systems, the particle size required to deliver these
products is larger and heavier than air. These particles
need to drop quickly and spread over the surface.
They contain powerful surfactants to help the product penetrate rapidly and thoroughly.
The desired
delivery system will lose minimal amounts of product to evaporation or to drifting.
Once a surface application is
completed, further control is unnecessary until new material is introduced
or the surface area is agitated, turned, or otherwise disturbed.
For example, a compost windrow treated
topically would need additional treatment after or during turning because one of the functions
of turning is
to move the surface material into the interior of the row and to move the internal material to the surface.
A new surface
is created by this action and therefore a new treatment is necessary.
Topical treatment is a very effective method of controlling
nuisance odors in landfills. Topical products are cost effective for large surface areas, and many landfills have water trucks on
hand. Adding a water cannon or fire nozzle to these trucks converts them to an excellent system for application of topical products.
Usually one or two applications per day (midday and closing) are sufficient to eliminate or contain most odors.
When treating liquid
substrates such as holding ponds, manure lagoons, or leachate ponds, remember that strong winds creating a choppy surface will be
constantly agitating and changing the surface materials. This makes these surfaces difficult if not impossible to treat topically
without regular re-application. The same is true for ponds and lagoons utilizing aeration or bubbling systems. Such applications are
far more suited to incorporation treatments.
As the name implies, these products are actually mixed, injected,
dripped, or otherwise infused into
a substrate. There are products suitable for liquid substrates, and products suitable for solid
substrates.
These products are utilized in composting, wastewater treatment, wet well and lift station treatment,
facultative lagoons,
and other applications.
In composting, methods such as static pile and aerated static pile are ideal for incorporation treatment.
The products may be incorporated at the same time the various feedstocks are being mixed together.
Incorporation is also ideal in
digesters and lift stations in wastewater treatment, where a drip system or
metering pump may be the only equipment needed.
GOC
does not primarily develop or sell bacterial products. Some GOC incorporation products work by
influencing the micro-biology of the
decomposing wastes in the substrate. By delivering selected nutrients
and oxygen-rich compounds, these products increase the presence
of microbes producing non-odorous
waste by-products while decreasing the presence of microbes which produce odorous by-products. This
is accomplished by modifying the substrate such that it enhances and encourages bacterial proliferation.
At Global Odor Control Technologies
we believe the substrate must be modified to support desired
microbial activity. Without a supportive substrate, the addition of bacteria
directly will be a brief fix that
must require continuous reapplication.
Other GOC products utilize chemical reactions such
as saponification (a reaction in which animal or vegetable fats, oils, and grease are converted to soaps) to eliminate the compounds
which facilitate odor formation.
GOC incorporation products are extremely cost effective and represent excellent alternatives to the
more conventional methods of air and surface contact.
Major examples of each method may be found in the applications section
of this site. The advantages and disadvantages of each method are outlined in the table below.
|
ADVANTAGE
|
DISADVANTAGE
|
|
Air Contact
|
|
May
be used anywhere
|
Larger perimeter areas may become cost prohibitive
|
|
Immediate impact
|
More equipment needed
|
|
Visibility to public
|
Treatment
must be on-going
|
|
Surface Contact
|
|
Ease of application
|
Impermanent; new surface requires new treatment
|
|
Capital equipment needs are minimal
|
Performance
may not be immediate
|
|
Cost effective
|
May not be visible to public
|
|
Incorporation
|
|
Single treatment
|
Requires time to be effective
|
|
Low cost
|
May
require product customization for each situation
|
|
May have value added benefits
|
|