Avaliação e proposta para um processo de tratamento de água na zona rural

Abstract

Drinking water is a privilege that people who live in rural areas often do not have access to. With a shortage of water treatment on rural properties, the population is very likely to consume contaminated water due to polluting agents that are, in general, animal waste, non-biodegradable organic matter and suspended solids. Consequently, there is a high probability of causing a series of diseases in the residents and the deterioration and/or corrosion of some materials used in the domestic environment. Water intended for human consumption is recognized as a vehicle for disease transmission. Maintaining microbiological water quality is essential, as it is a means of spreading diseases such as diarrhea, typhoid, cholera, salmonellosis and other gastroenteritis. With this, it is possible to verify the great importance of operations out in a water treatment plant, even with its main steps. Among these the method of sedimentation or decantation leaving the water cleaner and the filtration in which water passes through a type of porous medium in order to retain finer solids and correct the pH. Due to the lack of a more adequate procedure in rural areas, rainwater is usually stored in reservoirs, cisterns, wells, etc. This water is usually made available to residents by pumping it into a water tank, which it ultimately distributes to homes without any type of treatment. In view of the above, the objective of this Course Completion Work was to characterize the water of a rural property and propose possibilities for a possible water treatment with the main processes, seeking a low cost and water with parameters closer to the current water potability legislation in force for the population living in rural areas. The methodology that was applied consisted of collection, analysis of water characterization, jar-test, sedimentation test and proposal for water treatment in a rural property located on Batalha road in Bagé-RS. The characterization of the samples took place from July to September 2021 in the laboratories of the Federal University of Pampa - UNIPAMPA. Through characterization analysis, the results of analyzes such as pH, turbidity, electrical conductivity, dissolved oxygen, total dissolved solids and hardness were obtained. The pH had a range of 7 and the turbidity obtained results in the order of 11 NTU. The electrical conductivity was 108.8 µS/cm and the dissolved oxygen analysis was 6.04 mg/L. For the analysis of total dissolved solids, the result was 83.9 mg/L and for the water hardness 43.12 mg/L. In the jar-test method, the ideal dosage for the coagulant was obtained, pH correction and polymer addition was obtained. Therefore, for 1 liter of water, 0.09 g of Aluminum Sulfate (Al2(SO4)3) was used as a coagulant, 9 drops of Sodium Hydroxide (NaOH) at 5% for pH correction and 1 ml of anionic polymer [0.1g/L] to speed up the decanting process. In the sedimentation test, two procedures were carried out, one without the addition of polymer showing that with the addition of polymer, the sedimentation is more effective.