Giordano Urbini

Recovery of different waste vegetable oils for biodiesel production: a pilot experience in Bahia State, Brazil.

In Brazil, and mainly in the State of Bahia, crude vegetable oils are widely used in the preparation of food. Street stalls, restaurants and canteens make a great use of palm oil and soybean oil. There is also some use of castor oil, which is widely cultivated in the Sertão Region (within the State of Bahia), and widely applied in industry. This massive use in food preparation leads to a huge amount of waste oil of different types, which needs either to be properly disposed of, or recovered. At the Laboratorio Energia e Gas-LEN (Energy & Gas lab.) of the Universidade Federal da Bahia, a cycle of experiments were carried out to evaluate the recovery of waste oils for biodiesel production. The experiences were carried out on a laboratory scale and, in a semi-industrial pilot plant using waste oils of different qualities. In the transesterification process, applied waste vegetable oils were reacted with methanol with the support of a basic catalyst, such as NaOH or KOH. The conversion rate settled at between 81% and 85% (in weight). The most suitable molar ratio of waste oils to alcohol was 1:6, and the amount of catalyst required was 0.5% (of the weight of the incoming oil), in the case of NaOH, and 1%, in case of KOH. The quality of the biodiesel produced was tested to determine the final product quality. The parameters analyzed were the acid value, kinematic viscosity, monoglycerides, diglycerides, triglycerides, free glycerine, total glycerine, clearness; the conversion yield of the process was also evaluated.

Calculating specific denitrification rates in pre-denitrification by assessing the influence of dissolved oxygen, sludge loading and mixed-liquor recycle

This article presents the results of an experimental study on the correlation among the specific denitrification rate (SDNR), the dissolved oxygen concentration (DO), the F:M ratio (F:M) and the mixed-liquor (ML) recycle in the pre-denitrification reactors fed by domestic sewage. The experimental curves reveal a 28.8–32.0% reduction in the SDNR at 20°C () with DO equal to 0.1 mgO 2 L−1 and F:M in the range 0.2–0.4 kgBOD5 kgMLVSS−1 d−1. The SDNR reduction increases to 50.0–55.9% with DO=0.3 mgO2 L−1. A mathematical correlation of these results and an equation for calculating as function of the F:M as well as the average DO and BOD5 in the total flow rate fed in the denitrification stage are proposed. The conducted experience gives useful suggestions for practical usage, in particular regarding the denitrification reactor design, and represents a good starting point for future applications with the aim to optimize the biological process in domestic sewage treatment plants.

Automotive shredder residue: A survey of the hazardous organic micro-pollutants spectrum in landfill biogas

In this study, we report an extensive set of analytical results on the quality of the biogas produced by a landfill of automotive shredder residues. In particular, the investigation was directed towards the identification of a spectrum of polycyclic aromatic hydrocarbons (16 compounds) and a wide range of volatile organic compounds (35 compounds). This article highlights the most important indications of toxicological concern for the detected compounds. Among the polycyclic aromatic hydrocarbons, chrysene shows the highest concentration, followed by pyrene and benzo(b)fluoranthene. Dibenz(a,h)anthracene, the most carcinogenic of the tested compounds, displayed results below the limit of analytical detectability. Benzo(a)pyrene, another typical carcinogenic compound, was detected at low concentrations. With regard to volatile organic compounds, the survey revealed a relevant concentration of toluene (found in fuels and paint thinner) significantly higher than the other compounds. Noticeable amounts of hexane, trichloromethane, and acetone were also found.

Water Pollution: Biological Oxidation and Natural Control Techniques

In this article, all relevant biological oxidation processes for the treatment of wastewaters, based on both suspended and attached cultures, have been treated. Moreover, biological processes for the natural treatment (such as lagoons and constructed wetlands) have been taken into account. Particularly, an overview of the various processes, traditional and innovative, is offered by both citing a summary of their main features and highlighting all technological and process advances currently available in the literature.

Implementation of an integrated stationary - Non steady state Gaussian modeling system to simulate contaminants dispersion into the atmosphere

Implementation of an Integrated Stationary – Non Steady State Gaussian Modeling System to Simulate Contaminants Dispersion into the Atmosphere Massimo Raboni, Sabrina Copelli*, Mattia Tigoli, Vincenzo Torretta, Giordano Urbini, Giuseppe Nano Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta” Politecnico di Milanovia Mancinelli, 7 – 20133 – Milano – Italy Dipartimento di Scienza e Alta Tecnologia Università degli Studi dell’Insubria via Vico, 46 – 21100 – Varese – Italy Dipartimento di Biotecnologie e Scienze della Vita Università degli Studi dell’Insubria via Dunant, 3 – 21100 – Varese – Italy

NEW TRENDS IN MUNICIPAL SOLID WASTE MANAGEMENT IN ITALY.

Abstract In the last twenty years it can observe in Italy a strong quality evolution for Municipal Solid Waste. In particular the collected data outlined a reduction of the moist organic fraction from the 49% (by weight) to the real values, varying in the range from 20 to 25%. It can be noted a strong increase of the packaging material (paper and plastic). The average MSW heating value is increased from 1,500 kcal/kg to a value of about 2,500 kcal/kg. This evolution, together with some new Laws, make a strong change in the MSW disposal strategies. The raw refuse composting was neglected while a more and more great attention is given to the materials recovery by source selected collection and to the energy recovery by incineration.