Waste Management

Bio-facility managers must consider many issues when making decisions on the disposal of biological waste. The ‘waste’ being discussed in this article includes animal tissue, carcasses from necropsy rooms, and waste water from various wash-down procedures performed in pathology labs and necropsy rooms. Depending on the lab and the type of research or service being offered, a facility may be dealing with a whole gamut of waste ranging from highly infectious diseases down to non-infectious tissue, carcasses, and water waste.

What is the state of waste disposal in today’s lab animal facilities? The practice of incinerating waste continues in many facilities today simply because incineration has been used for years. Some of these older incinerators continue to function adequately but some are becoming increasingly unreliable, and some have high maintenance costs. All incinerators have high operational costs in terms of energy and maintenance compared to newer technology waste disposal systems. Users have claimed values as high as 64c to €1 per kilogram. Another fact of today’s world is a lab’s liability when carting waste to a landfill site or an incinerator off-site. The liability of that waste lies with the originator, the lab, forever. In today’s litigious business world, liability becomes an important consideration. Many facilities now find themselves planning for alternative means of waste disposal.

Figure 1 represents a logical approach to this quandary of what to do with bio-waste output from the many animal research and veterinary education facilities worldwide. The methods commonly used for waste disposal are:

1. Incinerator on-site
2. Transport to landfill
3. Transport to external incinerator or contract with waste processing company
4. Autoclave
5. Tissue Digester using Alkaline Hydrolysis process

Each of these methods will be explored in more detail here to minimise the perplexity of the alternatives.

(Click Image For A Larger Version)

Incinerator On-site
In addition to the issues stated above, permits must be considered when a facility wants its own incinerator on-site. In most municipalities, it is impossible to get a new permit for such an incinerator from either the EPA or the local community. With residential growth over the years, housing is closing in on existing research facilities and forcing them to shut down their incinerators. The basic rule of no incineration gases within eight kilometers of a residential area allows the EPA to enforce incinerator closures. With this doom over existing and future incinerators, alternatives must be investigated and planned.

Additionally, there are operational costs to consider. The cost of waste disposal using incinerators can run as high as 64c to €1 per kilogram. Some of the newer methods can get operational cost down to less than 14c per kilogram. The savings are significant. Given a facility that processes 2,722kg per week, this conservatively saves 55c per kilogram or €81,522 per year (2,722 kilograms X 50 weeks per year X 55c). Even facilities processing only at 454 kilograms per week would save €13,877 per year.