Constructed wetlands as an alternative for arsenic removal

Abstract

In Argentina, approximately 10% of the population consumes water with arsenic concentrations higher than the WHO and Argentine Food Code recommendations (10 µg L−1). Because of this, in some places reverse osmosis represented an immediate and effective solution to solve this problem. However, this process has a secondary effluent known as “concentrate” where all the elements present in the feed flow to this system are more concentrated. Sometimes, this residue is discharged in natural water bodies. In this work, the phytoremediation with constructed wetlands was proposed to solve the problem. The study was made from the design and construction of 3 prototypes, one of them implanted with J. effusus, another with C. haspan and a control one with substrate only. The percentages of arsenic removal were close to 50% with C. haspan and 80% with J. effusus. The technology was considered an efficient and environmentally sustainable solution to reverse osmosis effluent treatment and disposal.