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#207 - Hazardous Waste Incineration -- Part 4: Real Alternatives To Incineration, 13-Nov-1990

Why is there so much technical disagreement about the incineration of
hazardous waste? It is because different people emphasize different
aspects of the problem. A combustion engineer, who appreciates how
difficult it is to burn things completely with an open flame, is
button-bursting proud that any large machine can successfully destroy
99.99% of the chemicals fed into it (even if for only one day, the day
it's all tuned up for its trial burn, the outcome of which will
determine whether or not it gets licensed to operate). On the other
hand, a biologist looking at the same machine sees something completely
different. A biologist is concerned about keeping strange chemicals out
of the natural environment because such things tend to accumulate and
concentrate as they travel through the food chain. Creatures that live
at the top of the food chain become contaminated the most, and, in
general, humans eat high on the food chain. This is why human breast
milk is so contaminated with PCBs and pesticides that, if it were
bottled, the sale of human breast milk would be subject to ban by the
U.S. Food and Drug Administration (FDA). [See RHWN #193.] The breast
milk of American women no longer meets minimum FDA health standards for
human food. This is a direct result of releasing toxic PCBs and other
chemicals into the natural environment. A biologist looking at the EPA
(U.S. Environmental Protection Agency) plan to incinerate as much
hazardous waste as possible sees not a remarkable combustion
achievement but a real danger to humans and to the planet.

The U.S. presently produces at least 580 million tons of hazardous
waste each year (and possibly 5 times as much as this--the EPA still
doesn't actually know, according to the American Chemical Society [see
RHWN #148]). If we assume that the smaller number (580 million tons) is
true, and if we assume 99.99% of this were destroyed through
incineration, the remaining 0.01% that wasn't destroyed (and which
would inevitably enter the environment through air emissions or through
disposal of residual ash) would amount to 116 million pounds of
hazardous waste entering the environment each year, or about half a
pound for each man, woman, and child in America. Since many of these
chemicals are long-lived and are toxic in milligram or microgram
quantities, half-a-pound per person released into the environment is
substantial. Naturally, these toxics would not be evenly distributed;
people and communities near incinerators would be exposed far more than
the average.

It is worth pointing out that the 99.99% destruction goal is only
assumed by optimists, such as officials in charge of incinerator
permits at the EPA (U.S. Environmental Protection Agency). James Welch,
a scientist employed by the U.S. National Bureau of Standards, studied
the testing process whereby EPA decides that 99.99% destruction has
been achieved in an incinerator. His conclusion: the same numbers that
give the result 99.99% could with equal validity be shown to achieve
only 79.23% destruction. As every scientist knows, no measurement is
exact. Every measurement is approximate and has an upper boundary and a
lower boundary; the true value lies somewhere between the two
boundaries. To achieve a result of 99.99% you have to make an
optimistic assumption at every step in the trial-burn process; if you
simply change your viewpoint and make a pessimistic assumption at every
point, you can conclude that the very same test burn achieved only
79.23% destruction of wastes. Thus, Welch concludes, the actual
destruction of chemicals in an incinerator falls somewhere between
99.99% and 79.23%.[2] If all 580 million tons of U.S. hazardous wastes
were incinerated and only 79.23% were destroyed, incinerators would
emit nearly 21% into the environment, or 243 billion pounds (about 1000
pounds for every man, woman and child in America). Whatever number is
correct (between 116 million pounds and 243 billion pounds), to many
people, such a dousing of the planet with exotic toxic materials would
simply be unacceptable, especially because it is not necessary. They
reject incineration and they favor alternatives. What alternatives
exist?

There are so many alternatives to the incineration of hazardous wastes
that it is hard to know where to begin. The scientific and engineering
literature is bulging with descriptions of existing technologies,
available today, for managing wastes by means other than incineration.

The production and release of wastes into the environment is a direct
result of inefficient management, careless housekeeping, and obsolete
technology. Naturally, the most desirable option is to stop making
toxic wastes in the first place. Is such talk merely the stuff of
dreams? Hardly. The technical analysis unit of the U.S. Congress [the
Office of Technology Assessment (OTA)] in 1986 looked carefully at the
production of hazardous wastes in the U.S. and concluded that it would
be possible for American industry to cut its production of hazardous
wastes by 50% within 5 years using existing technologies.[1] To put it
bluntly, half of all toxic wastes are produced only because our
captains of industry are too unimaginative and too lethargic to do
things in a new way. If OTA's ideas had been acted upon in 1986, the
50% cut could be well along at this point and the nation would need no
new waste treatment capacity today.

But let's assume that America's industrial leaders will remain
unimaginative and lethargic and will not reduce waste production using
techniques that are readily available today. How could wastes be
handled if not by incineration?

As with household waste, the key to successful management is source
separation. Keep the wastes separate from each other, to keep them as
pure as possible, and you've got a decent shot at being able to reuse
them or recycle them through waste exchanges. Once they are mixed
together, no one can find any use for them and then they can only be
discarded or incinerated to recover their heat value (assuming everyone
is willing to accept the environmental degradation inherent in this
approach).

But let's assume that industry is run by people too unimaginative or
too lethargic to keep their wastes separate so they might be reused or
recycled through waste exchanges. What alternatives do such people have
available to them, other than incineration?

There are four major classes of waste treatment processes besides
incineration: phase separation, component separation, chemical
transformation, and biological treatment; within each of these broad
categories there is a large number of workable approaches;3 in
addition, there is spectrum of high-temperature processes that are not,
technically speaking, incineration but which achieve the same goal as
incineration (breaking molecular bonds via heat), though a lot more
cleanly.

What are phase separation techniques? Filtration, sedimentation,
flocculation, centrifugation, distillation, evaporation, flotation,
ultrafiltration, and precipitation, to mention only the better-known
ones. Component separation techniques include ion exchange, liquid ion
exchange, freeze crystallization, reverse osmosis, carbon adsorption,
resin adsorption, electrodialysis, air stripping, steam stripping,
ammonia stripping, ultrafiltration, solvent extraction, reverse
osmosis, distillation, and evaporation. Chemical transformation
processes include neutralization, precipitation, hydrolysis, oxidation,
reduction, ozonolysis, calcination, chlorinolysis, electrolysis, and
microwave treatment. Biological methods of treatment include too many
possibilities to list: there are microorganisms in nature that can
break down anything into its constituent elements and thus detoxify it
(unless of course the elements themselves are toxic, such as mercury or
thallium). Finding and cultivating such organisms is a matter of
putting knowledgable and competent investigators to work with clear
goals and adequate resources to accomplish those goals.

[More on alternatives next week.]

--Peter Montague

=====

[1] P.L. Ciriello and T. Goldberg, "Lead-Contaminated Soil Cleanup
Draft Report" which appears as Appendix E in: Agency for Toxic
Substances and Disease Registry, THE NATURE AND EXTENT OF LEAD
POISONING IN CHILDREN IN THE UNITED STATES: A REPORT TO CON- GRESS
(Atlanta, GA: Agency for Toxic Substances and Disease Registry, Public
Health Service, U.S. Department of Health and Human Services [1600
Clifton Rd. - Mail Stop E-33, Atlanta, GA 30333; phone (404) 639-0730],
July, 1988). Free while supplies last.

[2] Deborah Wallace, IN THE MOUTH OF THE DRAGON (Garden City Park, NY:
Avery Publishing Group [120 Old Broadway, Garden City Park, NY 11040;
phone (516) 741-2155], 1990). $17.95.

[3] For example, see Yen-Hsiung Kiang and Amir A. Metry, HAZARD- OUS
WASTE PROCESSING TECHNOLOGY (Ann Arbor, MI: Ann Arbor Science
Publishers, 1982).

Descriptor terms: hazardous waste incineration; breast milk; toxic
waste; james welch; health; national bureau of standards; studies;
chemical waste industry; waste treatment technologies; alternative
treatment technologies;