Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Afrique du Sud → 2020 → THE EFFICACY OF TWO BIOCHAR VARIANTS AS FILTRATION MATERIAL FOR THE IMPROVEMENT OF RIVER WATER QUALITY

Stellenbosch University (2020)

THE EFFICACY OF TWO BIOCHAR VARIANTS AS FILTRATION MATERIAL FOR THE IMPROVEMENT OF RIVER WATER QUALITY

Febbraio, Tanino

Titre : THE EFFICACY OF TWO BIOCHAR VARIANTS AS FILTRATION MATERIAL FOR THE IMPROVEMENT OF RIVER WATER QUALITY

Auteur : Febbraio, Tanino

Université de soutenance : Stellenbosch University

Grade : Master of Science (MS) in Food Science 2020

Résumé
The safety of irrigation water from rivers is continuously diminishing and has a direct effect on the safety of fresh produce. Not only can irrigation water be the source of pathogenic contamination, but it can also be a source of other physical and chemical contamination into the food system. The reduction or removal of these contaminants from river water for irrigational use may be achieved using a combination of water treatments. One such treatment includes the alternative use of biochar as a filtration media to improve the river water quality. Little is known about biochar as a possible adsorbent of contaminants from water mediums in filtration systems. The aim of the study was thus to determine the efficacy of biochar filtration to improve the river water quality. Open-ended filtration columns were constructed with two variants of biochar and compared to granular activated carbon (GAC). Untreated river water was exposed to these columns and analysed to determine the quality of the treated water both microbiologically and physicochemical. The pine and black wattle biochar, as well as the GAC, did not improve the microbiological quality of the untreated river water. In certain runs the heterotrophic plate count (HPC), faecal coliforms and Enterobacteriaceae were increased by the treatments, possibly due to the formation of biofilms in the columns. The pine biochar did, however, have the least negative effect on the microbial status of the untreated river water. Furthermore, the pine biochar was also more effective than the black wattle biochar and GAC at improving the COD, TSS, VSS, turbidity and UVT% of the untreated river water. The pine biochar filtration showed the most promising results and showed the most effective improvement on the UVT% of the untreated river water (from 33.9% to 97.7%). As a result of this improvement it was decided to expose the untreated river water to filtration and UV irradiation. The combined treatment with the biochar filtration and UV treatment lead to more effective and efficient reduction of microorganisms and the removal of STEC. Closed filtration columns were then constructed to enable complete saturation of the pine biochar filtration media.

Présentation

Version intégrale (3,40 Mb)

Page publiée le 22 juin 2022