Examination of poultry slaughterhouse wastewater sludge conditioning using microwave irradiation

This experimental study focuses on the changes to the physical and chemical characteristics of poultry slaughterhouse wastewater sludge exposed to varying microwave radiation energy levels, exposure time, and pH. Soluble chemical oxygen demand (SCOD), protein, and PO4-P releases obtained from the sludge were quantified as a function of irradiation energy, exposure time, and pH with the help of Box-Benhken statistical design. The maximum solubility values for SCOD (40.9 g/L), maximum protein (10.8g/L), and PO4-P (151 mg/L) were observed at the irradiation energy of about 1,002W with the exposure duration of 90 s at pH = 3. The sludge released 17% of its total COD and 12% of its total phosphorus. The temperature of the sludge sample was increased from 20 to 67 degrees C at exposure to 1,280W for 90 s. The capillary suction time (CST) of sludge samples decreased from an initial value of 200 s to 7.9 s at 1,280W at the exposure time of 50 s. The lowest specific resistance to filtration (SRF) value of 4.06 x 10(14) m/kg was measured at 50 s due to the existence of the dewatering properties in the sludge.