Avaliação de turfa em uma barreira reativa permeável para remediação de meios porosos contaminados com naftaleno e TEX

Abstract

The possibility of using a mixture of peat and sand based permeable reactive barrier (PRB) for aromatic hydrocarbon remediation was investigated. The selected aromatic hydrocarbons were naphthalene, toluene, ethyl-benzene, and xylene which are ubiquitous contaminants of soil and groundwater. Four sand-filled acrylic bench-top prototypes were constructed to evaluate four situations: i) PRB without added nutrients, ii) PRB with biostimulation, iii) PRB with biostimulation and bioaugmentation, and iv) control without a PRB. A tracer test with rhodamine was performed to evaluate the efficiency of the proposed PRB in the attenuation of organic contaminants. Attenuation of naphthalene, toluene and of the xylenes was significantly greater for all situations with PRB as compared to the control box. However, the attenuation of ethyl-benzene did not differ in any situation. Situations ii) and iii) had some evidence of biodegradation because the characteristic odor of hydrogen sulfide (H2S) and a dark precipitate in the sand were detected. These experiments highlight the potential use of mixture of sand and peat PRB for application in field cases, using cheap, readily available material.