Microwave Disposal of Medical and Pharmaceutical Wastes

On-site Disposal System for Biomedical Waste

Biomedical or medical waste consists of solids, liquids, sharps, and laboratory waste that are potentially infectious and must be properly managed to protect healthcare workers and the general public.  Biomedical waste is produced in hospitals, health clinics, nursing homes, medical research laboratories, offices of physicians, dentists, and veterinarians, and funeral homes.

Currently this waste is disposed in one of three ways; On-site, truck service, and mail-back disposal. On-site treatment uses expensive equipment, and is generally used by very large hospitals and major universities. Truck service employs a medical waste disposal service to collect and haul the waste in special containers for treatment at a central facility. Mail-back medical waste disposal is similar, except that the waste is shipped through commercial shippers instead of by private hauler.

75-90% of the medical waste is non-hazardous and comparable to other municipal wastes but 10-25% is hazardous and can be injurious to humans or animals and deleterious to environment. Over 90% of potentially infectious medical waste is incinerated and creates harmful air pollutants such as dioxins, NOx, and volatile organic compounds (VOCs). Stringent air emission standards are applied to medical waste incinerators.

Various sterilization processes are used to treat biohazardous waste on-site. The most common is   autoclaving, which uses steam and pressure to sterilize the waste. Other heat treatment such as microwave technology may also be used to sterilize the waste. The problems with these treatments are the high equipment and treatment costs. In addition, the volume of waste is not reduced and it still must be disposed off-site.

Medical facilities separate their medical waste into three separate containers; non-hazardous, sharps, and biohazardous waste. CHA Corporation has developed a system to destroy biohazardous medical waste on-site as produced.  The disposal system consists of three reactor systems: 1) Microwave Solid Disposal Unit, (2) Microwave Cracker and (3) Microwave Oxidation Unit.

The first reactor destroys liquid and solid medical wastes.  The solid medical waste is fed into the reactor through top and is partially oxidized and pyrolyzed by air and microwaves. The gas and tar from the reactor enter the microwave cracker to produce hydrocarbon gases. The hydrocarbons are completely oxidized in the microwave oxidizer. The exhaust from the microwave oxidizer contains no air pollutants including nitrogen oxides (NOx) and volatile organic compounds (VOCs).  The volume of material that must be disposed off-site is reduced by at least 95%, resulting in cost savings.

Microwave On-Site Disposal System for Pharmaceutical Waste

The discovery of a variety of pharmaceuticals in surface, ground, and drinking waters around the country is raising concerns about potential adverse environmental consequences of these contaminants. Pharmaceutical waste is composed of many distinct waste streams that reflect the complexity and diversity of their chemical composition. Pharmaceutical waste is generated through a wide variety of activities in a healthcare facility, including but not limited to intravenous (IV) preparation, general compounding, spills/breakage, partially used vials, syringes, and IVs, discontinued, unused preparations, unused unit dose repacks, patients’ personal medications and outdated pharmaceuticals.

CHA’s biohazardous waste disposal technology is also applicable to dispose pharmaceutical waste. Using the same process, solid and liquid wastes are pyrolyzed, cracked and oxidized with no air pollutant generation.  The only product generated from the process is ash that may be disposed in a landfill.

The main advantage of microwave disposal system is to destroy small quantities of solid and liquid pharmaceuticals on-site as produced economically without producing air and water pollutants.