Recyling of domestic gray water

Treatment systems are an option in water recovery in order to find solutions to the current situation of water resources and climate change, and to reduce the potential effects of climate change on water resources. On average, 65% of domestic wastewater consists of gray water, which includes wastewater produced in homes, excluding toilets. The barrier to graywater reuse relates to pathogens, nutrients and organic matter found in gray water. There are different biological treatment processes for graywater treatment. One such system is the sequential batch reactor (SBR), which has proven to be an effective way to treat wastewater. When the graywater to be treated is used for non-potable purposes, it can reduce fresh water consumption and ensure water safety. The aim of this study was to examine the performance of real graywater in the treatment of the SBR reactor and to investigate how suitable it can be for reuse. A 25-30 L aquarium was used as the SBR reactor. Graywater was obtained from a residence of approximately 20-24 people, where 6 families live in Izmit district of Kocaeli province. The primary microorganism of the reactor was activated sludge from a local municipality. Initially, graywater was run on 1 day and 2.5 day HRTs. The aim here was to examine the treatment efficiency of the system and to learn the system. As a result of the studies, it has been seen that 2.5 days of HRT produces more efficient results. In addition to the SBR reactor, sieving was applied as a primary treatment to increase the treatment efficiency. pH average in results obtained at 2.5 days of fixed HRT. 8.11, electrical conductivity avg. 860 µS/cm, dissolved oxygen approx. It has been measured around 7.43 mg/L. The removal efficiencies are; yields were 99% for turbidity, 98% for TSS, 88% for phosphate, 90% for total nitrogen, 89% for COD and 98% for BOD. Treated graywater was partially able to meet the reuse standards prescribed by WHO. According to WPCR, it is seen that wastewater meets the wastewater standards stipulated in the discharge of wastewater treatment plants (WWTP).