est nucleargenerating capacity in the world yet nuclear reactors generate only 18 percent of the power required by Americans, although several states rely on nuclear energy for more than half of their electricity supply. Here in Canada, 15 percent of all the electricity produced comes from nuclear power plants. How ever, the provinces of New Bruns wick and Ontario rely more heavily on nuclear power. In 1988, Ontario's 16 GANDU reac
tors produced about 50 percent of that province's electricity and a single unit at Point Lepreau gen erated 40 percent of New Bruns wick's electricity.
strong economies by creating their own nuclear generated elec tricity sources. Today, nuclear power provides roughly 50 per cent of the electricity produced in these countries. Availability of electricity at a competitive cost has placed them at the forefront of international competition. Those countries with emerging international economies as well
as developing nations will require vast supplies of energy if they are to grow and provide better health and food for their populations. The options for these emerg ing economies are often very
Nuclear power is not new Splitting the uranium atom to generate the heat that is used to produce steam forthe production of electricity, has been a commer
cial reality for more than 30 years. The world's electric utilities have
more than 5,000 reactor years of operating experience. This is equivalent to 419 reactors in the world today times the number of
years each has been producing electricity.
Canada is the world's largest supplier of uranium to electric utilities worldwide. This availabil
energy rich like Canada. Their choices in many instances are to
ity of uranium combined with Canada's CANDU, the best per forming reactor technology in the world, puts Canada at the fore
cut and burn their forests, to use
front In nuclear energy today and well into the next century.
trialized countries, it is more and
vast quantities of local or imported coal or to build and operate their own nuclear power
more a choice for developing
reactors.
countries which do not have natu
Without secure and dependa ble supplies of electricity many of
A growing need in the worid Nuclear energy is not only an appropriate alternative for indus
ral energy resources in their own territory. Newly developed coun tries such as South Korea and Taiwan have been able to build
limited as most of them are not
these
countries
remain
impoverished and underdeve loped.
Letter on solvent recovery Dear Mr. Davey,
Our 15 plants in the National Capital region have been using a system to eliminate the production of hazard ous toxic waste in stills since January, 1989. To follow how it has helped, it is necessary to explain how a drycleaning machine works.
A typical machine would consist of the following: (A)the main drum of the machine which contains the garments; this is similar to the drum of an automatic
washing machine. A control system will enable the machine to process the garments through a cycle suit able for the type of garments to be cleaned. Normally this will be a wash in solvent pumped up from the base tank (B), a spin to remove solvent, and a warm air drying cycle to evaporate the solvent from the gar ments.
This drying cycle takes place in a closed circuit where the air in the machine is blown by a fan(F)from
a heater(H)over the garments and to a condenser(C2). Solvent is thus removed from the air which is then
reheated and passed back to the drurii to remove more solvent.
At the end ofthe drying cycle any solvent which has not been condensed is purged from the system by open ing a vent. This purge then passes to and is absorbed by a secondary recovery system, usually a refrigera tion unit. The solid soils are rapidly removed in the wash and deposited onto the filter (F). The non-solid
soiling is dropped to the still and is boiled. The vapours rise from the still to the condenser (Cl) and the solvent is returned to the base tank via a water
separator.
would
This article was sponsored by the Canadian Nuclear Association. For further details contact the
GNA, 111 Elizabeth St., Toronto, Ontario, MSG 1P7, Tel: 1-800387-4477.
Circle reply card No. 118
MacLarentech Inc. Hazardous Waste Specialists Safe, cost-effective hazardous waste management Is essential for industry today. As environmental regulations become more complex, so do the potential liabilities faced by generators of hazardous waste The need for sound methods to reduce, handle and dispose of hazardous waste has never been greater.
MacLarentech Inc. is an experienced, full-service engineering firm. We develop comprehensive waste management programs tailored to the specific needs of your industry and your company. Our hazardous waste management services include:
»/n-plant waste audits • Waste handling and transportation • Waste cleanup •Asbestos surveys •PCB management • Water and waste treatment'
•Contingency planning •Emergency response •Plant and site decommissioning •Community relations •Regulatory approval •Site remediation •Site characterization
•Containment systems and storage structures •Laboratory analysis MacLarentech Inc.
Atria North — Phase II
2235 Sheppard Ave. E. Willowdale, Ontario, M2J 5A6, Canada Contacts: Rick German and Art Seanor
Tel: (416) 756-9453, FAX: (416) 756-4998
Continued overleaf
Environmental Science & Engineering, October 1989
Circle reply card No. 119
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