Combined microfiltration and adsorption process applied to public water supply treatment: water quality influence on pesticides removal.

Granular activated carbon (GAC) fixed bed adsorption technology was applied to remove carbamates carbaryl, methomyl and carbofuran from public water supply. In order to minimize the effect of clogging and to evaluate adsorbent saturation for carbamates, the microfiltration (MF) was previously used to adsorb and the backwash procedure of the GAC bed was carried out. The determination and quantification of the carbamates were performed by analytical technique in high performance liquid chromatography with post-column derivatization and fluorescence detector.

Performance of the fixed-bed of granular activated carbon for the removal of pesticides from water supply.

The application of a fixed bed adsorption column of granular activated carbon (FBAC-GAC), in the removal of carbaryl, methomyl and carbofuran at a concentration of 25 μg L for each carbamate, from the public water supply was investigated. For the determination of the presence of pesticides in the water supply, the analytical technique of high-performance liquid chromatography with post-column derivatization was used. Under conditions of constant diffusivity, the FBAC-GAC was saturated after 196 h of operation on a pilot scale.

Combination of electroflotation process and down-flow granular filtration to treat wastewater contaminated with oil.

Unlabelled: One of the main problems faced by the oil industry is related to the amount of produced water generated during the oil extraction process. For proper disposal of this effluent, treatment processes should be applied to meet the requirements established by environmental agencies. Thus, the present study aimed to evaluate the efficiency of the combination of electroflotation process and down-flow granular filtration in the treatment of wastewater contaminated with oil.

Study of slow sand filtration with backwash and the influence of the filter media on the filter recovery and cleaning.

Slow sand filters are considered as a great alternative for supplying drinking water in rural and/or isolated areas where raw water that is treatable with this technique is available. Some studies used backwashing as an alternative for cleaning the slow sand filter with the goal of applying the technology in small communities, since filters that supply water to a small number of people do not require much space. In this study the influence of the effective diameter on water quality in the filters and cleaning system was evaluated.