Section Five
WASTE MINIMIZATION
83    RESOURCE RECOVERY FROM COATING INDUSTRY
SOLIDS
Charles A. Cole, Professor
Rita G. Blatt, Associate Professor
The Pennsylvania State University
Middletown, Pennsylvania 17057
Andrew G. Odell, Plant Chemist
Philadelphia Electric Company
Peach Bottom Atomic Power Station
Delta, Pennsylvania 17314
Edward J. Ruch, Sanitary Engineer
Lykens, Pennsylvania 17048
INTRODUCTION
The coatings industry, which includes paints as well as other products used as coatings, produced in
1987 over $10 billion of product representing approximately a billion gallons of coatings. The paints
and allied products industry includes Standard Industrial Codes, SIC 28511 to 28519.2 Paints typically
include three components: binders, pigments, and solvents. The binder or vehicle, hardens to form a
continuous film that adheres to the object to be coated. The pigment provides the desired color. The
solvent is a volatile material which aids in spreading the paint as it is applied to a surface. A typical oil
based paint may contain natural or synthetic oils as a binder, a metallic oxide or organic dye as the
pigment and a mixture of hydrocarbons as the solvent.3 By contrast, a typical water-based paint most
likely would contain a synthetic polymer as the binder. Among the polymers used in latex paints are
polyvinyl acetate, acrylics, alkyds, polystyrene, and styrene-butadiene copolymers. These polymers
are present in a water emulsion along with appropriate pigments. In addition to these basic components, many additives, such as, fillers and plasticizers are used to get desired effects.
WASTE MINIMIZATION
Waste minimization as defined by EPA means the reduction to the extent feasible of solid and
hazardous waste that is generated and subsequently treated, stored or disposed of. It is being encouraged at the present time as a result of the 1986 Report to Congress on waste minimization.4 Several
general approaches to waste minimization have been proposed; they include inventory management
and improved operation, modification of equipment, production process changes, and recycling and
reuse.
Sources of paint-waste solids include spent packaging, off-standard and out-of-date products,
clean-out and clean-up solvents, and pollution control equipment. At present, it is standard practice
for solvent recyclers to recover solvents from the waste paint and sell them for reuse. In addition,
solvents which are not easily reused, about one-fourth of the total, are burned in cement kilns. The
remaining solvents and solids usually stored in drums, and to a lesser extent those in tanks and stills
are presently not reusable and must be incinerated.5 This method of disposal is very expensive and
costs may range up to $500 per fifty-five gallon drum. Industries in the Commonwealth of Pennsylvania generate between 20,000 and 50,000 drums of this type of hazardous waste per year which results
in an estimated annual disposal cost of $15,OO0,OOO.5
46th Purdue Industrial Waste Conference Proceedings, 1992 Lewis Publishers, Inc., Chelsea, Michigan 48118.
Printed in U.S.A.
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