Key Caboratory of Chinese Ministry of Education of northwest Water Resource and Environmental ecolog School of environmental and Municipal Engineering 声建墨群骨 xi'an University of Architecture and Technology BOD in domestic wastewate COD and BoD in 口 Dissolved口 Suspende domestic wastewater 2 Dissolved average 39.54% Suspended average: 60.46% COD in domestic wastewater 口 Dissolved口 Suspended More than 60% of COD or BOD in the domestic wastewater are suspended matter Less than 40%o of coD or BOD 3 in the domestic wastewater are Sample Number Dissolved average 34.12 dissolved matter Suspended average: 65.88%Key Laboratory of Chinese Ministry of Education of Northwest Water Resource and Environmental Ecology School of Environmental and Municipal Engineering Xi’an University of Architecture and Technology COD and BOD in COD and BOD in domestic wastewater domestic wastewater • More than 60% of COD or BOD in the domestic wastewater are suspended matter. • Less than 40% of COD or BOD in the domestic wastewater are dissolved matter