The goal of this study is to suggest the use of a biochemical model to optimize the design and management of biological compartments of a wastewater treatment plant, giving attention to CO2 emissions from aerated tanks. The CO2 emissions have been considered because a large amount of carbonaceous matter incoming in the wastewater is of petroleum origin. The bicarbonate system is introduced into the model to simulate the fate of CO2 from the liquid to the gas phase. Literature data are used to verify the model. The error analysis shows no apparent bias and root mean square error close to zero. However, a deviation of 15% is found and the error is not homogeneous even for data referred to the same plant. Therefore, the model can be considered affordable even though more investigations are necessary to improve its performance. Therefore, a sensitivity analysis is carried out via the Morris Method and the gas temperature appears the most sensitive parameter on the direct CO2 emissions due to biological processes inside the bioreactor. The model is used to evaluate the trend in CO2 emissions by varying firstly the configuration of the bioreactor from CSTR to PFR, and later the size of the bioreactor. An increase in the CO2 emissions in moving toward the PFR configuration is recorded, due to the rapid change of biochemical reactions in PFRs. A decrease in the CO2 emissions was observed by increasing the reactor depth.
NEW MODELLING APPROACHES TO SIMULATE GREENHOUSE GAS EMISSIONS FROM THE BIOLOGICAL COMPARTMENT OF WWTPs FOR IMPROVEMENT OF PLANNING AND MANAGEMENT
CAIVANO, MARIANNA;CANIANI, Donatella;MASI, Salvatore;MANCINI, Ignazio Marcello;
2016-01-01
Abstract
The goal of this study is to suggest the use of a biochemical model to optimize the design and management of biological compartments of a wastewater treatment plant, giving attention to CO2 emissions from aerated tanks. The CO2 emissions have been considered because a large amount of carbonaceous matter incoming in the wastewater is of petroleum origin. The bicarbonate system is introduced into the model to simulate the fate of CO2 from the liquid to the gas phase. Literature data are used to verify the model. The error analysis shows no apparent bias and root mean square error close to zero. However, a deviation of 15% is found and the error is not homogeneous even for data referred to the same plant. Therefore, the model can be considered affordable even though more investigations are necessary to improve its performance. Therefore, a sensitivity analysis is carried out via the Morris Method and the gas temperature appears the most sensitive parameter on the direct CO2 emissions due to biological processes inside the bioreactor. The model is used to evaluate the trend in CO2 emissions by varying firstly the configuration of the bioreactor from CSTR to PFR, and later the size of the bioreactor. An increase in the CO2 emissions in moving toward the PFR configuration is recorded, due to the rapid change of biochemical reactions in PFRs. A decrease in the CO2 emissions was observed by increasing the reactor depth.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
