effect of hydraulic retention time (hrt) in an anaerobic baffled reactor (abr) on the reduction of bod and cod in slaughterhouse industrial wastewater

The slaughterhouse industry generates large volumes of wastewater with high pollutant levels, such as biological oxygen demand (bod) and chemical oxygen demand (cod). this study investigates using anaerobic baffled reactor (abr) technology with predetermined hydraulic retention time (hrt) to treat slaughterhouse wastewater containing bod and cod. the study was carried out in the abr reactor with a volume of 20,000 cm³ of wastewater on a laboratory scale. the study employed two hrts: a 2-hour hrt (2h), wastewater was monitored at intervals of 2h for 10h, and a 6-hour hrt (6h), wastewater was monitored at 6h intervals over 30h. undiluted (rph-ud) and diluted (rph-d) slaughterhouse wastewater were used. in the context of abr technology, the hrt of the 2h and 6h applications demonstrated a strong correlation in reducing bod₅ and cod levels in slaughterhouse wastewater. the correlation values between the two variables were within the range of 0.95 to 1.0. the most efficient values for the bod₅ and cod parameters were attained at an hrt of 6h. for bod₅, rph-ud achieved a peak efficiency of 62.31%, while rph-d reached 87.37%. regarding cod, both rph-ud and rph-d exhibited their highest efficiencies with values of 66.98% and 92.69 %, respectively.