Alessandro Petrozzi

Evaluation of the odor impact of some environmental gaseous pollutants: calibration of the methodology and preliminary results

During the last decades, it has been observed a growing interest on odor impact because of the frequenter social acceptability problems about energy plants handling and processing stored organic materials (e.g., biogas plants, landfills, farms, distilleries, etc.). In this context, the UNI EN 13725:2004 indicates the “dynamic olfactometry method” as validated, recognized, and adequate measurement procedure for estimating the odor concentration. This protocol is carried out by a panel of specifically trained and selected human receptors, but alternative analytical methodologies are currently under discussion. This work aims to describe the initial steps of a wider research toward the definition of a new analytical protocol for monitoring odor concentration. The alternative methodology is here presented through the implementation of a case study: stored organic materials exploited on an energy plant in Central Italy. The paper describes the preliminary activities related to the survey of the case study (i), the definition of alternative methods and devices for conducting emissions sampling (ii), and the adopted experimental approach (iii). Finally, preliminary results are also presented (iv). The resulting protocol, once validated, could be employed by local authorities to measure both the odor impacts and the effectiveness of specifically designed mitigation strategies.

Energy from poultry waste: An Aspen Plus-based approach to the thermo-chemical processes

A particular approach to the task of energy conversion of a residual waste material was properly experienced during the implementation of the national funded Enerpoll project. This project is a case study developed in the estate of a poultry farm that is located in a rural area of central Italy (Umbria Region); such a farm was chosen for the research project since it is almost representative of many similar small-sized breeding realties of the Italian regional context. The purpose of the case study was the disposal of a waste material (i.e. poultry manure) and its energy recovery; this task is in agreement with the main objectives of the new Energy Union policy. Considering this background, an innovative gasification plant (300KW thermal power) was chosen and installed for the experimentation. The novelty of the investigated technology is the possibility to achieve the production of thermal energy burning just the produced syngas and not directly the solid residues. This aspect allows to reduce the quantity of nitrogen released in the atmosphere by the exhaust flue gases and conveying it into the solid residues (ashes). A critical aspect of the research program was the optimization of the pretreatment (reduction of the water content) and the dimensional homogenization of the poultry waste before its energy recovery. This physical pretreatment allowed the reduction of the complexity of the matrix to be energy enhanced. Further to the real scale plant monitoring, a complete Aspen Plus v.8.0 model was also elaborated for the prediction of the quality of the produced synthesis gas as a function of both the gasification temperature and the equivalence ratio (ER). The model is an ideal flowchart using as input material just the homogenized and dried material. On the basis of the real monitored thermal power (equal to about 200kW average value in an hour) the model was used for the estimation of the syngas energy content (i.e. LHV) that resulted in the range of 3-5MJ/m3 for an equivalence ratio (ER) equal to 0.2.