Use of treated greywater as inoculum for BOD monitoring: A sustainable approach

Abstract

The growing population, increasing water consumption, and consequent rise in pollution, coupled with climate change impacts on global aquatic ecosystems, underscore the critical importance of responsible water resource management in promoting sustainable development and to ensuring that future generations have access to water of adequate quantity and quality. The need for water reuse has emerged as viable alternative to mitigate issues related to water scarcity, highlighting innovative approaches to water utilization. Greywater refers to used water from sinks, bathrooms, showers and washing machines which has a high potential for reuse after appropriate treatment, such as filtration and disinfection, among other methods. One of the filtration methods for greywater involves the use of biofilters composed of worm humus, wood, sand, rocks and other natural materials. Greywater (biowater) can be applied in various processes, such as serving as seed in BOD analysis, which measures the concentration of organic matter based on the amount of oxygen consumed by microorganisms during its oxidation. In this context, the objective of this study is to evaluate the feasibility of reusing greywater treated through to biofilter as seed for BOD analysis. Laboratory assays were conducted using greywater sample as seed at concentrations of 20, 100, and 200 mg/L of O₂ over a period of nine weeks, yielding average results of 21.69, 96.52, and 189.68 mg/L of O₂, respectively, indicating promising outcomes.