Evaluation of custom-made and commercial greywater treatment systems: A case study from Oman

This paper reports a study to evaluate two types of greywater treatment systems; commercial and custom-made. Commercial greywater treatment systems are expensive for small quantities. Therefore, a cost-effective, low maintenance treatment system was designed to collect, treat and re-use ablution water from small- to medium-sizes mosques. The system included a sand trap, an ablution water collection tank, a filtration unit, chlorination chute, and treated water collection tank. Treatment and re-use was automated using submersible pumps and timers. The study revealed that both the commercial and custom-made systems were capable of treating greywater to satisfy relevant government regulations in Oman. The financial analysis showed that the internal rate of return (IRR) for custom-made and the commercial systems for the mosques were 14.9% and 19.06% respectively. IRR for the commercial system at private house was -1.44%. Costs of the systems and the amount of greywater treated were the main factors affecting the IRR.