ASSESSMENT OF CHROMIUM REMOVAL BEHAVIOR THROUGH HORIZONTAL SUBSURFACE WETLANDS

Abstract

Introduction:
Water pollution is one of the main environmental problems affecting Cuba. The galvanic and leather tanning industries in the same country generate wastewater contaminated with chromium which can be treated using constructed wetlands.
Objective:
To evaluate chromium removal behavior in experimental subsurface wetlands.
Materials and Methods:
Two experimental systems consisting of horizontal subsurface flow wetlands were constructed: one planted with Cyperus Alternifolius and the other with two varieties of Heliconia (Rostrata and Wagneriana), using red ferrallitic soil as substrate. The Atomic Absorption Spectrometry method was used for the determination of total chromium and Excel of the Office package in its version 16.0.17726 was the software adopted for statistical processing.
Results and Discussion:
The Cyperus Alternifolius was the species that showed the best assimilation, managing to transport the metal to the leaves. The kinetics of chromium removal in the wetland and in the soil used as substrate were evaluated, demonstrating the importance of plants and associated microorganisms in the retention of the metal, with higher retention in the wetland. Chromium removal efficiencies of over 98% were obtained.
Conclusions:
Using the Cyperus Alternifolius plant together with the red ferrallitic soil, and performing the corresponding scaling with the kinetic constants obtained, it is possible to construct a treatment system that efficiently removes chromium from wastewater associated with the galvanic industry and tanneries.