Assessing the Viability of Rainwater Harvesting System for Sustainable Manufacturing in Water Stressed Regions

Abstract

Abstract Water is considered to the life wire of many manufacturing industry. Water is used for processing of materials, cooling of engines, firefighting and also important for sanitation and welfare of workers. As the population of the world increases, the demand for water to meet domestic and industrial needs of man increases. In line with sustainable development, there is need for practices in manufacturing which will help preserve scarce resources for domestic needs. The global trend in industries is sustainable manufacturing which is hinged at increasing operational efficiency and as well reducing cost and wastages. As a result, there is a growing interest on rainwater as an alternative source. In this paper, the rainwater harvesting system was assessed to establish its viability for a small scale pozzolana plant for sustainable manufacturing. The methodology adopted was estimating water consumption in the production plant and potential harvestable rainwater from the roof top. The harvestable rainwater was estimated based on the rainfall data obtained from the Famine Early Warning Systems Network (FEWS NET) and the rooftop (catchment) area was determined by taking dimensions of the rooftop to establish the area while a collection efficiency of 90% was assumed. Design and operational parameters from literature was used to describe the effectiveness of the system for the study area. Results revealed that water demand to run the plant for production and sanitation for staff welfare can be covered substantially using rainwater with a reliability of 99.7% and annual water savings of 1,350,000.00. The investment is viable and will be amortized in only 1.6 years. The rainwater harvesting system will generate economic benefits by reducing the cost of production and consequently the selling price will be reduced for consumers.