shredding or grinding). The treatment process is required to destroy the
potential of the waste to cause adverse human health effects, to pose physical
hazards, or to aesthetically degrade the environment.
Treatment Method Selection Guidance. There are significant
comparative advantages and disadvantages for each of the RMW treatment
currently available in the industry. Waste management and handling
regulations have currently not stabilized to the point that a single treatment
technique can be recommended to meet the needs of all projects.
outlines technologies which are currently considered effective for on-site RMW
treatment. Note that processes used by centralized or commercial facilities,
such as irradiation and thermal inactivation treatments for large volumes of
liquid and solid RMW, are not presented here.
Shredding and Grinding Equipment. In and of themselves, shredding
or grinding processes do not constitute treatment methods. Shredding or
grinding equipment must be used in a manner which does not introduce
aerosolized untreated RMW into the air, and complies with OSHA and EPA
regulations for employee health and safety.
Retort Steam Sterilization. Retort steam sterilization is a
common method of treating RMW by use of saturated steam under pressure to
accomplish the complete destruction of all microorganisms. Use of a retort
steam sterilizer, in concert with a grinder for rendering the treated RMW
"unrecognizable", makes this process viable in the anticipated regulatory
climate. Grinding should be done following sterilization, in conjunction with
a compactor or container located at the soiled dock.
Limitations of Method. Aesthetic considerations, and the dense
nature of human and animal body parts which preclude thorough steam
penetration, make sterilization ineffective for this application. Similarly,
sterilization cannot be effectively utilized for large volumes of liquids, or
Sterilizer Type. Vacuum sterilizers process RMW more effectively,
and in less time, than gravity displacement units, and should be utilized for
Mechanical Cart Dumper. Systems which employ a mechanical cart
dumper to transfer bagged RMW from the holding cart to the sterilizing cart,
or use the same cart for collecting, holding and sterilizing RMW, should be
utilized to reduce the potential for injury or contamination of waste handling
Incineration. Incineration was a primary method used to treat and
destroy RMW in past years when the plastics content of the waste was low.
Higher air quality standards and increased public concerns regarding air
emissions have resulted in difficulties with permitting and operation
of incinerators, as well as increasing capital and operational costs
substantially. On-site incineration should not be considered.
Microwaving of RMW. This is accomplished by a technique which
heat. Microwaving is not suitable for treatment of large pathological
wastes, such as body parts and animal wastes. In addition, the technology is
currently restricted to treatment of RMW which is less than 10% liquid content
by total weight, and metallic content of less than 1% by total weight (with no
piece of metal exceeding a weight of 0.5 lb). Advantages of microwaving
systems are their effective destruction of RMW and reduction of waste volume
by 80 percent.