Biomedical subjects

Francesco Pirozzi

Publications and source records attributed to Francesco Pirozzi.

3 recordsLinked to original sources

PubMed2006

Optimal design of predenitrification systems.

A coupled model of biological and settling phases aimed at optimal design of predenitrification systems is presented. Each unknown is obtained in explicit form, and is expressed as a function of the system's required performance. A model, taking into account both suspended and dissolved substrates, is adopted for the biological phase, while the limiting solid flux theory is assumed for the design of the settling phase. Finally, a relationship correlating the two phases is obtained expressing opportunely the sludge recycle flow and the sludge waste flow, without recourse to empirical parameters. The effect of different influent and effluent wastewater characteristics on the model's results is also analyzed.

Biodegradation, Environmental↗

PubMed2005

Evaluation of biodegradation kinetic constants for aromatic compounds by means of aerobic batch experiments.

Kinetics of aerobic biodegradation have been investigated for twenty aromatic species using sludges collected from the aeration basin of municipal sewage treatment plants. The reproducibility of the results is tested with respect to the sludges period of collection and the wastewater treatment plant where they are taken. The comparison of kinetic constants, estimated for the investigated chemicals, allows to evaluate the reactivity effect of single groups (i.e., -OH, -CH3, -Cl, -NO2) into the aromatic structures. The search for easy structure-reactivity relationships is also attempted by means of contributing group methods.

Aerobiosis↗

PubMed2005

Sequencing batch reactor performance treating PAH contaminated lagoon sediments.

The applicability of sediment slurry sequencing batch reactors (SBR) to treat Venice lagoon sediments contaminated by polycyclic aromatic hydrocarbons (PAHs) was investigated, carrying out experimental tests. The slurry, obtained mixing tap water and contaminated sediments with 17.1 mg kg(-1) TS total PAHs content, was loaded to a 8l lab-scale completely stirred reactor, operated as a sequencing batch reactor. Oxygen uptake rate exerted by the slurry, measured by means of a DO-stat titrator, was used to monitor the in-reactor biological activity and to select the optimal operating conditions for the sediment slurry SBR. The PAHs removal efficiency was evaluated in different operating conditions, obtained changing the hydraulic retention time (HRT) of the lab-scale reactor and adding an external carbon source to the slurry. HRT values used during the experiments are 98, 70 and 35 days, whereas the carbon source was added in order to evaluate its effect on the biological activity. The results have shown a stable degradation of PAHs, with a removal efficiency close to 55%, not dependent on the addition of carbon source and the tested HRTs.

Biodegradation, Environmental↗