| abstract |
Process waste waters at a pH of about 7 contaminated with radioactive isotopes are decontaminated by (a) adjusting the pH to about 5.8, (b) adding CaO or Ca(OH) 2 to raise the pH to about 8.5, (c) agitating the mixture for at least 5 minutes to effect intimate contact and produce a suspension of solids containing radioactive contaminants, and (d) separating the suspension of solids from the water by centrifuging. Removal of radioactive uranium isotopes with an alpha emission is effected at a pH of about 10. The process provides a method for concentrating radioactive contaminants in water for subsequent ultimate storage and also purifies the contaminated water so it may be safe to discharge it into the sewer. The treatment may be carried out in a plurality of stages in series. |