TREATMENT OF WASTE WATER CONTAINING METAL AND AMMONIA

摘要

PROBLEM TO BE SOLVED: To separate and remove metals in waste water and to prevent the lowering of the performance of a noble metal carrying catalyst by bringing the waste water into contact with a chelate resin or an ion exchange resin, separating metal hydroxides deposited by adjustment to a specified pH range and then bringing the waste water into contact with the catalyst under coexistence of oxygen-containing gas. SOLUTION: Waste water is passed through a resin packed tower 3 packed with a chelate resin or an ion exchange resin to remove prescribed metal ions and metals are deposited as hydroxides in a storage tank 4 by adjustment to pH 8-12 with alkali. The water containing the deposited metal hydroxides is subjected to solid-liquid separation in a filter 6. The effluent of the filter 6 freed of the metal hydroxides is sent to a pipe under pressure, mixed with oxygen-containing gas compressed by a compressor 9 in the pipe, heated to a prescribed temperature through a heat exchanger 10 and a heater 11 and passed through a catalytic reaction tower 12. The treated water flowing out of the reaction tower 12 is cooled through the heat exchanger 10 and a cooler 13. In a vapor-liquid separator 14, waste gas and treated water are separated.