A method of removing one or more heavy metals from industrial wastewater
by use of a membrane separation process is disclosed. Specifically, the
following steps are taken to remove heavy metals from industrial
wastewater: (a) collecting an industrial wastewater containing heavy
metals in a receptacle suitable to hold said industrial wastewater; (b)
adjusting the pH of said system to achieve hydroxide precipitation of
said heavy metal in said industrial wastewater; (c) adding an effective
amount of a water soluble ethylene dichloride- ammonia polymer having a
molecular weight of from about 500 to about 10,000 daltons that contain
from about 5 to about 50 mole percent of dithiocarbamate salt groups to
react with said heavy metals in said industrial wastewater system; (d)
passing said treated industrial wastewater through a submerged membrane,
wherein said submerged membrane is an ultrafiltration membrane or a
microfiltration membrane; and (e) optionally back-flushing said membrane
to remove solids from the membrane surface.