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Context: The use of natural coagulants for water clarification is being globally researched due to their low cost, high biodegradability, and ability to replace highly toxic synthetic coagulants. Knowledge gap: The water of the Ciénaga Grande (Great Swamp in English) in Atlantico Department, Colombia, is used for cleaning, consumption, and food preparation by the inhabitants of the area. However, it does not comply with water quality for human consumption, as defined by the Resolution 2115 of 2007 regarding the turbidity parameter. For this reason, it is important to analyze the synergy generated by using the coagulant combination of moringa seeds and cassava starch in the search to improve its conditions. It is important to note that there are few reports in the literature on the simultaneous use of these coagulants. Purpose: This research aims to evaluate the clarification of the water from Ciénaga Grande using mixtures of natural coagulants composed of moringa seeds and cassava starch to reduce its turbidity. Methodology: The combinations of coagulants, moringa seeds, and cassava starch, were mixed with a ratio of 90:10, 80:20, 70:30, and 60:40, respectively. The turbidity and pH of Ciénaga Grande water were evaluated. In addition, clarification was simulated in accordance with the regulation NTC 3903 of 2010 with each treatment. It began with agitation at 120rpm for 1 min., then an agitation at 30rpm was carried out for 20 min., and, finally, it was left to sediment for 15 min. Then, a sample was extracted from each jar, and the final turbidity was measured. A factorial design was carried out for each coagulant combination, with six dose levels (mg/L) and one response variable, the final water turbidity (nephelometric turbidity unit, NTU). The analysis of variance ANOVA and Duncan's multiple range test were carried out using 95% reliability. Results and conclusions: The treatment with the highest turbidity removal (NTU) was treatment 4, which has a 60:40 ratio of moringa seeds and cassava starch. Additionally, the turbidity parameter decreased by 80.4%. The doses used in treatments 1, 2, and 3 influenced the final turbidity of the water. It was concluded that high initial turbidity increases the coagulating activity of the natural mixture, causing a higher removal of such a parameter. [ABSTRACT FROM AUTHOR]

The growth of the poultry industry in Colombia, and the change in current environmental regulations, leads to an improvement in the wastewater treatment system, through alternate techniques between coagulants and flocculants. The cost of these techniques require optimal dosing of the main products involved therein. In this work, we used an artificial neural model based on feedforward-backpropagation multilayer neural networks, to estimate the value of output turbidity in the treatment of wastewater. The trained neural networks subsequently used to propose optimal dosages of the products and improve the operating conditions that allow obtaining clarified wastewater, so we develop optimization charts. We used the R linear correlation factor as a performance indicator, for the evaluation of the performance of the neural model. The correlation results between the estimated a real values of the output turbidity show its reliability in the application as a prediction tool. [ABSTRACT FROM AUTHOR]

Environmental phenomena cause a strong impact in the variation of the quality of sources for drinking water, demanding that potable water treatment processes respond to these changes and maintain quality standards in the production of safe drinking water. The historical analysis of river Cauca turbidity and behavior of clarified and filtrated water allowed evaluating the effect of increase in raw water turbidity over water treatment conventional processes of Puerto Mallarino plant at Cali (Colombia). It was determined that the high turbidity of the water of river affected the treatment efficiency and also the quality of treated water; filtration was the most vulnerable stage to these high turbidity events. A high linear correlation between maximum turbidity and chemical products dose (coagulant and disinfectant) was identified. [ABSTRACT FROM AUTHOR]