Method for encapsulating and containing asbestos on power plant equipment

The present invention discloses a method for encapsulating and containment of asbestos covered workpieces such as power equipment material. A resin and catalyst mix is applied to the asbestos covered surface. Glass is applied with the resin or after the resin. The surface is then compacted by brushing or rolling, to provide consistent application and to remove air bubbles. In certain instances, this material is applied to a chopped roving which is then applied to the surface prior to compaction. In the preferred embodiment, a chopper gun is used to apply the resin, catalyst, and glass mixture.

BACKGROUND OF THE INVENTION 
The present invention relates generally to a method for encapsulating and 
containing asbestos on power plant equipment, and more particularly to a 
method for encapsulating and containing the asbestos on power plant 
equipment, instead of removal, through use of a resin and glass fiber 
material. 
It will be appreciated by those skilled in the art that in the past, power 
plant equipment such as steam and hot water pipes, turbines, feed water 
heaters, condensers, hot air ducts, wind boxes, and the like were coated 
with asbestos to prevent fires. Unfortunately, this practice has led to 
asbestos being a danger to workers in the area, because as asbestos ages, 
fibers from the asbestos enter the air and enter the respiratory systems 
of individuals. To this end, there have been several attempts to remove 
this asbestos danger from power plant equipment. 
One such attempt is the removal of the asbestos by some type of scraping or 
cutting from the power plant equipment. Unfortunately, studies have shown 
that this method actually increases the amount of airborne asbestos fibers 
in the area, thereby increasing the danger. Studies have shown that the 
asbestos needs be covered. 
Another attempt is to encapsulate and contain the equipment in some type of 
metal, such as an aluminum sheet jacket. However, this method has problems 
such as cost and the ability to seal joints. 
What is needed, then, is a method to encapsulate and contain asbestos on 
power plant equipment that is quick and efficient to use. This needed 
method must be cost effective. This needed method must be able to 
withstand the differences in temperature experienced by power plant 
equipment and the wear and tear suffered by the coating. This needed 
method must encapsulate and contain the asbestos instead of removal, to 
prevent an increase in airborne asbestos fibers. This method must have 
consistent encapsulation and containment properties, even at joints. These 
properties are presently lacking in the prior art. 
SUMMARY OF THE INVENTION 
In the present method, a mixture of resin, glass, and a catalyst is applied 
to the surface of power plant equipment to encapsulate and contain the 
asbestos. In the preferred embodiment, an unsaturated polyester resin is 
used as the resin. Methyl ethyl ketone peroxide is used as a catalyst. 
Glass fibers are used for the glass. This can be applied by either by 
spray with a chopper gun, placed on a mat, cloth, or stitch mat by hand; 
or applied with a brush. Certain pigments may be added according to OSHA 
requirements or according to the user's desire. This method can be used to 
encapsulate and contain asbestos on any type of power plant equipment such 
as pipes, turbines, and the like. 
Accordingly, an object of the present invention is to provide a method for 
encapsulating and containing asbestos on power plant equipment that is 
quick and efficient. 
Still another object of the present invention is to provide a method for 
asbestos encapsulation and containment that is cost effective. 
Another object of the present invention is to provide a method of asbestos 
encapsulation and containment that can withstand the temperature extremes 
in power plant equipment and the wear and tear experienced by the coating 
and the workpiece. 
Still another object of the present invention is to encapsulate and contain 
asbestos as opposed to removing it. 
Another object of the present invention is to provide consistent properties 
throughout the surface, including at joints.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
A resin, glass, and catalyst are combined and applied to the surface of the 
asbestos on power plant equipment. These three materials are combined to 
form a bonding fiberglass. In the preferred embodiment, unsaturated 
polyester resin, which is a thermal setting polymer that is classified as 
a plastic, is used as the resin. Methyl ethyl ketone peroxide, which is a 
strong oxidizing agent, is used as the catalyst. Glass fibers in the form 
of chopped fibers, mat, or cloth are used for application. 
In one method, a chopper gun is used to simultaneously spray the chopped 
glass and the catalyzed resin on the surface. This sprayed glass and resin 
is then rolled out or brushed to provide a consistent surface. 
This material can also be applied by hand by placing a net, cloth, or 
stitch mat containing glass fibers and catalyzed resin on the surface to 
be covered. In essence, the surface is wrapped with this material. After 
the wrapping is complete, the wrapped section is then conditioned with 
either a roller or brush to ensure that all glass fibers are saturated 
with resin and are smooth and free of air pockets. 
Any color pigment can be added to the mix, according to the user's desire 
or according to OSHA requirements for type of equipment, temperature, and 
pressure. 
In the preferred embodiment, the sealant is approximately 1/8 inch in 
thickness or thicker. However, any thickness can be used as long as the 
fire retardant capabilities of the resin is maintained. 
In the preferred embodiment, the unsaturated polyester resin is in the 
amount of substantially sixty percent by weight. A styrene monomer is used 
in the amount of substantially forty percent by weight. Epichlorohydrin is 
used at substantially 1/2 percent by weight. Because of the sensitivity of 
the methylethyl ketone peroxide catalyst, the chopper gun mixture must be 
performed inside the gun in order to ensure that none of the catalyst 
comes out by itself, which would occur in an external mix. In the 
preferred embodiment, substantially five percent by weight of antimony 
pentaoxide is combined with the styrene monomer to form the resin. This 
forms a chlorendic-based resin. 
In the preferred embodiment, a Venus-Gusmer, low pressure airless chopper 
gun is used, having an internal mix. This gun uses low pressure without 
air assistance, which produces large droplets which remain within the 
spray pattern, resulting in less overspray and a much better working 
environment. 
As discussed previously, the present method can be performed using either a 
hand preparation or a spray or spray up. A hand lay up is a process of 
applying the material, resin, and fiberglass by hand, using a brush or 
roller, without the aid of spray equipment. In a spray up, chopped or 
continuous glass is sprayed simultaneously or alternately with catalyzed 
resin onto the surface. 
In a hand lay up, the resin is pre-catalyzed and then applied to the 
surface using a brush or nap roller. A precut sheet of mat or woven 
material is placed onto the wetted surface and rolled or brushed to remove 
the air voids and ensure consistent application. If the laminate is mat 
only, a roller or brush is used. If the laminate contains a woven 
material, the woven material is put behind the mat, and then a squeegee is 
used. 
In a spray up, substantially 11/2 inch glass fibers are deposited 
simultaneously with catalyzed resin onto the surface. This is performed by 
a hand operated chopper gun that chops glass and sprays catalyzed resin so 
that the two merge and are directed onto the surface. Because there is no 
need for other types of matting or roving material, this method uses the 
least expensive raw materials. 
The spray method can be used on large surfaces such as hot air ducts and 
feed water heaters. However, a hand application must be used on pipes and 
seals that are too small to be effectively sprayed. 
Thus, although there have been particular embodiments of the present 
invention of a new and useful method for encapsulating and containing 
asbestos on power plant equipment, it is not intended that such references 
be construed as limitations upon the scope of this invention, except as 
set forth in the following claims. Further, although there have been 
described certain dimensions used in the preferred embodiment, it is not 
intended that such dimensions be construed as limitations upon the scope 
of this invention, except as set forth in the following claims.