Département Procédés Propres et Environnement, Laboratoire de Modélisation, Mécanique et Procédés Propres UMR CNRS 6181, Europôle de l'Arbois-Bâtiment Laennec-Hall C, BP 80–13545, Aix en Provence, France
In wastewater treatment by constructed wetland, the biodegradation capability of the biomass developed in the soil is one of the most important factors. For this kind of treatment unit, soil properties are studied to improve its filtration capacity and hydraulic residence time of the wastewater. The impact of soil properties like porosity and soil components on biomass development and biodegradation capacity seem to be less studied certainly due to the complexity of microbial identification techniques currently used. The study presented here is a preliminary work to validate that calorimetric technique could be a tool in the understanding of biodegradation capacity of wastewater treatment processes. Biofilm is preliminary developed in columns filled with different porous materials of well known porosity and constitutive components. These columns are fed with the same continuous flow of synthetic solution (C, N, and P) as a substrate amending during 3 weeks. Then each week, 2 mL samples of porous media from these columns are analyzed in isothermal calorimeter for 48 h. Net heat flow is recorded before and after substrate injection. This work results in the definition of the procedure for batch experiments in calorimeter for wastewater process efficiency. The results of these experiments show that the microbial reaction due to substrate amendment is highly depending on the porous material used for biofilm growth. Indeed calorimetric signals recorded lead to conclude that biofilm grown on plastic beads has a faster and more intensive reaction to glucose amendment than biofilm grown on glass beads. At least, two glass beads samples analyzed in the calorimeter after the same duration of feeding with synthetic solution have very different response to glucose or synthetic solution.
2. Prochaska, CA, Zouboulis, AI, Eskridge, KM2007Performance of pilot-scale vertical-flow constructed wetlands, as affected by season, substrate, hydraulic load and frequency of application of simulated urban sewage. Ecol Eng31:57–66.
Prochaska, CA, Zouboulis, AI, Eskridge, KM2007Performance of pilot-scale vertical-flow constructed wetlands, as affected by season, substrate, hydraulic load and frequency of application of simulated urban sewage. Ecol Eng31:57–6610.1016/j.ecoleng.2007.05.007.)| false
Molle, P, Liénard, A, Grasmick, A, Iwema, A2006Effect of reeds and feeding operations on hydraulic behaviour of vertical flow constructed wetlands under hydraulic overloads. Water Res403606–61210.1016/j.watres.2005.11.026.)| false
Akratos, CS, Tsihrintzis, VA2007Effect of temperature, HRT, vegetation and porous media on removal efficiency of pilot-scale horizontal subsurface flow constructed wetlands. Ecol Eng292173–19110.1016/j.ecoleng.2006.06.013.)| false
von Stockar, UVojinović, V, Maskow, T, Liu, J2008Can microbial growth yield be estimated using simple thermodynamic analogies to technical processes?. Chem Eng Process Process Intensif476980–99010.1016/j.cep.2007.02.016.)| false
18. Nunez-Regueira, L, Nunez-Fernandez, O, Rodriguez Anon, JA, Proupin Catineiras, J2002The influence of some physicochemical parameters on the microbial growth in soils. Thermochimica Acta394:123–131.
Nunez-Regueira, L, Nunez-Fernandez, O, Rodriguez Anon, JA, Proupin Catineiras, J2002The influence of some physicochemical parameters on the microbial growth in soils. Thermochimica Acta394:123–13110.1016/S0040-6031(02)00245-9.)| false
Barros, N, Feijoo, S, Simoni, JA, Airoldi, C, Ramajo, B, Espina, A, Garcia, JR2008A mass and energy balance to provide microbial growth yield efficiency in soil. J Therm Anal Calorim93–2:657–66510.1007/s10973-007-8871-4.)| false