Evaluation of a Sustainable Automated Hand Washing System Equipped with a Water Recycling Device

The need for regular hand washing to prevent the spread of covid-19 and other viruses in our society has become a new normal. Therefore, due to the need to comply with the World Health Organisation (WHO), guidelines of washing hands regularly to reduce the risk of contracting infections an automated hand washing system was developed with an installed water recycling device. The incorporation of recycling water is to guarantee effective management of energy resources and to reduces environmental pollution. The conceptual architectural design with the aid of AutoCAD software and the incorporation of an Arduino micro controller unit was established. Also, the theoretical knowledge of science and engineering was used to design, construct, and assembled the automated washing machine system with an installed reactor for wastewater treatment, soap dispensers, sensors, water pump, water gauge, water tank,s and micro controller. The working operations with the assembling of relevant sensors enabled liquid soap to be dispensed for 1 second to allow the users to rub their hands for 20 seconds and dispense water for 21 seconds to wash their hands. The used water was filtered to clean water with the aid of a filtration reactor. The clean water then flows into the lower tank and is sent back to the upper tak for reuse by the submersible pump in the lower tank. The water treatment was achieved by adding 13g of aqueous $CaCo_{3}$ and MgSo4 into 180g of used water. The water sample was then analysed in the laboratory to ascertain its purity. A short interview was conducted with fifty people to determine their level of satisfaction with the use of an automated hand-washing system. The performance evaluation was also carried out on the system. The following results were obtained, 98% of the respondents expressed satisfaction with the automated hand washing system. The purity of the treated water was 98.9% for the chemical oxygen demand (COD) and 99.6% for total nitrogen (TN). The microcontroller was successful in coordinating the various activities of the automated system. Conclusively, the developed machine satisfactorily meets the need of covid-19 protocol and effectively reduces the wastage of water.