To provide a heavy metal removal method for easily removing heavy metal compounds such as selenic acid and selenious acid from the water to be treated.
Calcium ions and aluminum ions are added to waste water W containing heavy metal compounds being selenic acid, selenious acid, arsenic acid, arsenous acid, hexavalent chromium and their salts. The pH of the waste water W is regulated to produce sludge M containing aluminum and calcium as a principal component in the waste water W. The heavy metal compounds are taken into the sludge. The sludge M is subjected to solid-liquid separation from the waste water W after the production of the sludge M, so that the heavy metal compounds can be removed from the waste water W. The removal of heavy metal compounds from the waste water W can easily be performed with a simple constitution.
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