This work presented experimental and modeling studies on the simultaneous absorption of H2S and CO2 into the N-methyldiethanolamine (MDEA) and piperazine (PZ) solution in a rotating packed bed (RPB). The effect of different operating conditions, including MDEA concentration (C-MDEA), PZ concentration (C-PZ), liquid volumetric flow rate (L), temperature (T), and high gravity factor (beta) on the absorption efficiencies of H2S and CO2 (eta H2S and eta CO2) were investigated. The results showed that eta H2S and eta CO2 were significantly affected by C-MDEA, C-PZ, L, and beta. eta H2S and eta CO2 could reach 99.98 and 96.51%, respectively. Furthermore, an artificial neural network (ANN) model was established to predict eta H2S, eta CO2, and mass-transfer coefficient (K(G)a). Results showed that the predicted values were in good agreement with the experimental values (within deviations of +/- 10% for H2S and CO2). This work provides a potential technology of simultaneous absorption of H2S and CO2 for the biogas upgrade.