Filtrates and sludges from an industrial plant for treatment of wastewaters from prodn. of Pb-acid batteries were obtained by chem. treatment with a com. Praestol 2500 and TMT 15 agents as well as with aq. soins. of NaOH, Na2CO3 and lime to remove Pb in a form of hardly soluble coordination compds. The Pb concn. was decreased from 3.08-6.17 mg/L down to 0.17-0.63 mg/L as a result of the 3-stage pretreatment.