Water is an essential element for human survival, yet many individuals still lack access to treated water to meet their basic needs. To mitigate this situation, alternative water treatment technologies that are accessible and easy to handle are being explored. Among these, the use of Moringa oleifera seeds as a natural coagulant and the application of a helically coiled tube as a flocculation unit have been studied. In this context, this study aimed to evaluate the turbidity removal efficiency using two different coagulants (Moringa oleifera and aluminum sulfate) in an alternative water clarification system. The system consists of a helically coiled tube flocculator (HCTF) coupled with a conventional decantation unit. It was observed that the coagulant solution from shelled seeds required a lower dosage to achieve efficiencies above 90% compared to the coagulant solution from seeds with shells. The optimal dosage was 30 mL/L of the coagulant solution from shelled seeds. This dosage resulted in high turbidity-removal efficiencies, ranging from 92% to 100%. The processing method of the seeds that yielded the highest efficiency in turbidity removal was the mortar and pestle, as opposed to a blender. The optimal configuration of the alternative water clarification system comprised using the lower HCTF in a horizontal orientation. The use of the alternative water clarification system, along with the natural coagulant, proves to be a promising alternative clean technology for water clarification in locations without access to conventional treatment, being efficient in turbidity removal.

The use of natural solutions has gained increasing attention as a sustainable alternative for water treatment. In this study, an Aloe vera-based coagulant was evaluated through jar test experiments and a laboratory-scale hydraulic system consisting of an alternative flocculator (such as a helically coiled tube) followed by sedimentation and filtration processes. The jar test experiments demonstrated high turbidity removal efficiency, achieving final turbidity values of 5 NTU or lower under all the tested conditions, in accordance with international environmental regulations and standards. Moreover, in some conditions, turbidity was completely eliminated, highlighting the remarkable coagulation performance of Aloe vera. In the hydraulic system, the results indicated a significant turbidity reduction, with turbidity removal efficiencies of up to 97%, coagulation/flocculation times under 2 min, and sedimentation times of 60 min. However, the combined coagulation, flocculation, and sedimentation processes were not sufficient to reduce the final turbidity to below 5 NTU, demonstrating the need for an additional rapid filtration step. The inclusion of this process further enhanced the particle removal, resulting in final turbidity values below 1 NTU, well within the regulatory limits. These results highlight the potential of the tested natural coagulant for application in water treatment systems, establishing it as a sustainable and cost-effective solution for water clarification, with promising prospects for large-scale implementation.

Access to safe drinking water is a major challenge for vulnerable populations, especially in regions with limited infrastructure. The use of chemical coagulants in water treatment presents environmental and health risks due to their non-biodegradable byproducts, which contaminate ecosystems. Natural coagulants offer a safer alternative, as they decompose naturally and reduce pollution. However, their production often requires complex methods, such as microfiltration and lyophilization, which are unsuitable for resource-limited areas. This study introduces a simplified method for producing a natural coagulant from the seeds of Moringa oleifera, eliminating the need for complex techniques or saline solutions. The process involves peeling, grinding the seeds, stirring with water, and filtering through paper filters, producing the coagulant in under 30 min. Coagulation tests showed complete turbidity removal with 5 mL of coagulant per liter of water at 100 NTU. This economical and environmentally sustainable method offers a practical solution for improving water treatment in resource-limited communities.