Design and construction of a recyclable grey water treatment system of a solar-powered washing machine with soap doser

Abstract

Grey water (sullage) is liquid wastewater generated from washrooms, laundries, kitchens which does not contain human or animal excreta. Due to an increase in the percentage of water discharged from laundries, there is a lot of greywaters discharged that needs to be recycled and reused. Regular water shortages in some parts of Uganda have led to poor sanitation in the people’s homes of residence, hospitals and institutions due to lack of enough water for showering and cleaning around the shower room. This project is about designing, constructing, building and testing of a recyclable grey water treatment system of a solar powered top-load type washing machine with a soap dozer that uses less water by utilizing the available greywater from laundries to supplement on the accessible surface and ground water source in the country, uses solar power to reduce energy consumption, and also doses soap during washing. In our design, greywater quality was determined by collecting samples and testing them using different water quality sensors like turbidity and electrical conductivity sensors, generated quantity of water was determined depending on the total water consumption per house holes. Design of various components of the system was done using the given relevant formulas and equations. greywater generated in our system was 20 litres per wash load i.e. a 7kg drum can wash a double duvet or towels and sheets for small family with an efficiency of 90% and the discharged water exhibited poor physical and chemical characteristics and thus needs treatment before reuse. Distribution pipes, collection tank was sized then treatment units where Jain super flow Y filter was selected and clear tank, pump, storage tank was sized.