Preliminary Study on the Treatment Efficiency of Pasteurized Lime Thermal Alkaline Hydrolysis for Excess Activated Sludge and Reduction of Tetracycline Resistance Genes

Thermal alkaline hydrolysis is a common pretreatment method for the utilization of excess activated sludge (EAS). Owing to strict environment laws and need better energy utilization, new methods were developed in this study improve efficiency method. Direct thermal (TH), pasteurized (PTH), (PTH + CaO PTH NaOH) used treat EAS. Each was compared analyzed terms dissolution ammonium nitrogen (NH4 + -N) soluble COD (SCOD) Furthermore, removal tetracycline resistance genes (TRGs) class 1 transposon gene intI1 from EAS investigated. The NH4 -N SCOD concentrations treated by 1.24 2.58 times higher than those TH. However, total TRGs between groups comparable. concentration NaOH group 4.37 that group, increased 9.52% with PTH. could reach 85.04% 92.14% but 19.78% lower NaOH. Thus, reduce financial cost actual operation, lime (CaO) can be instead strong alkali (NaOH), steam at 70°C conventional high-temperature heating This provides reference development under moderate temperatures along