Estudo do lodo de estação de tratamento de água sob influencia da implementaçao de pré e inter-oxidação.

Abstract

This work presents an analysis of the pre- and inter-chlorination raw water treatment process. This, in turn, aims to: achieve better results in the coagulation stage, remove color and turbidity, remove algae, oxidize organic matter to prevent the addition of biofilm on the filters and walls of flocculators and decanters, remove specific metals or even with purpose of disinfection. Furthermore, there is positive evidence that treatment with oxidants can influence conventional water treatment processes, reducing the dosage of coagulants and improving the quality of treated water. In this context, this study proposes an analysis of waste generated at the Bom Jardim de Uberlândia/MG, verifying the influence of pre and interchlorination, applied concomitantly with conventional treatment, on the characteristic of sludge (LETA) and filter washing water (ALAF), regarding the physical-chemical parameters and whether there was a reduction in the amount of waste generated. For this, the adopted methodology followed the idealization of campaigns, being carried out in two moments, the first campaign was carried out two collections and different dates for samples without the adoption of pre- and inter-chlorination, and the second campaign was carried out with the collection of samples after ETA Bom Jardim adopt pre and inter-chlorination. The result was a significant reduction in parameters with total iron, total aluminum, total manganese and lead, in addition to a significant change in the composition of the final ETA sludge. Therefore, based on the research carried out, it is concluded that the adoption of pre and inter-chlorination processes had positive results in the reduction of some physicochemical parameters in the waters of the ETA. For the effluent from the decanters, parameters such as total iron and total aluminum presented about 152% and 11%, respectively. While for the filter backwash effluent, the analytical results showed total iron, total manganese and total aluminum reduced by about 24.45%, 36% and 40.61%, respectively, for each parameter. However, despite the positive results of pre- and inter-chlorination, it is recommended to better understand the contact time of the oxidant and the relationship between the use of chlorine and the formation of THM, as some authors cite this behavior in ETAs, as well as to do use of other oxidizers at the pilot level in order to establish comparative efficacy results.