Tratamento de água para comunidades rurais usando Moringa Oleifera como coagulante natural

Abstract

Having access to quality water is a fundamental right of the human being, regardless of social class or education. The families that live in communities in diffuse places, for the most part, do not have any form of treatment in their water supply, which has as main source of water the small barrages (dams). Generally, water treatments present the coagulation step as a fundamental process for the success of subsequent steps. There are several chemical coagulants, such as aluminum sulphate, ferric chloride, aluminum hydroxychloride and ferric sulphate, which require specific technical preparation of the operators, in addition to not having such affordable costs. As a substitute for chemical coagulation, some vegetable coagulants, such as Moringa oleifera, have been studied and present advantageous results in substitution of chemical coagulation for being biodegradable and nontoxic. Water scarcity is no longer explained solely by the lack of quantitative water, but also by the contamination and pollution of water bodies. Thus, the research proposes to elaborate a technique of unidomiciliar treatment with the use of the extract of the seeds of the moringa adding to the stage of slow filtration with the clay filter for the stage of clarification and, finally, with the social technology SODIS (Solar Water Desinfection ) For disinfection. The objective of this work is to propose an alternative of unidomiciliar treatment of water that fits the reality of the rural families of the northeastern semi - arid region, who do not have treated water. The objective is that the treatment has efficient inputs, cost-effective and does not harm the environment. It is important to study technologies that allow the adaptation of man to rural life through access to quality water. The limnological variables analyzed were pH, turbidity, Biochemical Oxygen Demand - BOD and Thermotolerant Coliform - CTT. The study area was the May 25 settlement, Madalena-CE, which houses about 600 families. In the settlement, the main source of water supply is the dams, for general uses. The Quieto dam, medium-sized (15 hm³), is the most important in the settlement and was practically the only one that was able to withstand the multi-year drought (2012-2016) that devastated the region. The Quieto dam (or Marengo) directly assists three communities in the settlement (Quieto, Vila Angelim and Raiz) and was the water source chosen for this study. The proposed technology (use of natural coagulant, filtration and subsequent disinfection with SODIS) showed efficiency in reducing the physical-chemical and bacteriological parameters analyzed. However, such technology has limitations and should be improved. Among the main limitations are: (i) the high time required for filtration; And the low efficiency in reducing cyanobacteria.