Characteristics of sewage of Mobini Hospital, Sabzevar, Iran

Introduction: Hospital sewage, if not purified, can result in the spread of infectious diseases
and environmental pollution. This study aims to evaluate the qualitative and quantitative
characteristics of Sabzevar city Mobini Hospital sewage and to provide appropriate treatment
plans for this kind of sewage.
Materials and methods: The quality and quantity of crude sewage of Mobini Hospital was
evaluated in this cross-sectional study. Water consumption data was collected from water
bills. Per capita sewage production was calculated through identifying the waste production
ratio from consumed water. Twelve samples were collected and analyzed for biochemical
oxygen demand (BOD5), chemical oxygen demand (COD), sewage sludge treatment (SST),
total coliform (TC), and PH.
Results: Average water consumption and waste production per hospital bed were 569 and
512 liters per day and the waste production ratio was 0.9. Mean pH, BOD5, COD, and SST
were 8.2, 240 mg/L, 640 mg/L, and 291 mg/L, respectively. The coliform most probable
number was more than 1100 in 100 ml.
Conclusion: According to the findings of this study, a biological treatment method, such as
rotating biological contactor (RBC), should be used for hospital sewage, followed by
clarification and a chemical treatment due to the high level of COD.