ZEOTREAT: MULTIFUNCTIONAL ADSORBENTS FOR METAL AND SULPHATE REMOVAL IN MINING WASTEWATERS FROM COPPER INDUSTRY, CHILEAN CASE

摘要

Over the last 5 years Fundacion Chile's Environment Program has carried out specific research for the development, adaptation and implementation of innovative technologies for the treatment of mining wastewaters with metal and sulphate content, incorporating the concept of waste recovery and water reuse. One of the most well developed technologies is ZEOTREAT~(TM) which involves the chemical modification of Chilean natural zeolites to obtain multi-adsorbent material for the removal of specific contaminants. The modified zeolites are an organo-mineral complex obtained from the treatment of mordenite (a type of zeolite from Chile) with a cationic detergent. They have the ability to adsorb oxyanions of: arsenic, As(III) and As(V), molybdenum, selenium and sulfur (sulphate), without losing the natural capacity to adsorb cations such as: copper, nickel, lead, among other. This technology provides an integral solution for the treatment of mining wastewaters and also has advantages in diluted matrices where there are no conventional, cost-efficient alternatives. The wastewater treatment system is based on a continuous flow where the contaminants are adsorbed in packed columns which contain the adsorbent; either upgraded and/or modified zeolites, depending on the specific application needed.