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In this paper an original energy recovery method from composting is analyzed. The integrated system exploits the heat available from the aerobic biochemical process in order to support the drying of sewage sludge, using a specific solar greenhouse. The aim is to tackle the problem of organic waste treatment, with specific regard to food waste. This is done by optimizing the energy consumption of the aerobic process of composting, using the heat produced to solve a second important waste management problem such as the sewage waste treatment. Energy and mass balances are presented in a preliminary feasibility study. Referring to a composting plant with a capacity of 15,000 t/y of food waste, the estimation of the power from recovered heat for the entire plant resulted about 42 kW. The results demonstrated that the energy recoverable can cover part of the heat necessary for the treatment of sludge generated by the population served by the composting plant (in terms of food waste and green waste collection). The addition of a renewable source such as solar energy could cover the residual energy demand. The approach is presented in detail in order for it to be replicated in other case studies or at full scale applications.

Con il termine di eterotopia dell’ansa spirale del colon (ASCA) sono comprese delle anomalie di forma e di posizione di questo tratto di intestino in vario grado caratterizzate dalla mancata adesione delle spire al piano mesenteriale. Con la finalità di stimare la prevalenza di tali anomalie e verificare l’entità del problema, questo lavoro presenta un’indagine prospettica svolta su un campione di 1113 vitelli c.d. “a carne bianca” soggetti a normale macellazione, ed un’analisi retrospettiva delle note di 160 necroscopie di vitelli al di sotto di sei mesi di età. L’indagine al macello ha evidenziato la presenza di eterotopia dell’ASCA in 472 soggetti (42,4%); le devianze erano rappresentate principalmente da una scarsa aderenza al mesentere (381/1113 = 34,2%); situazioni di distacco più o meno completo dell’ASCA dal disco mesenteriale sono state osservate in 91 soggetti (8,2%). L’analisi retrospettiva ha evidenziato la presenza di eterotopia dell’ASCA in 32 casi. Viene discussa e giustificata anche l’ipotesi che l’eterotopia dell’ASCA possa rappresentare un elemento favorente i cambiamenti di posizione dell’intestino; la predisposizione sarebbe basata su uno sbilanciamento del centro di gravità (baricentro) del pacchetto intestinale con conseguente ridotta capacità, da parte dell’intestino o di tratti di esso, di conservare la propria posizione quando sollecitato a movimenti abnormi.

The spiral colon is formed as the result of a lengthening and coiling of the midgut ascending limb. The literature reports two arguments that explain the details of such a development: the first argues that the spiral loop is formed to the left of the mesentery (Asari et al. Jpn J Vet Sci 47, 1985; McGeady et al. Veterinary Embriology, 2006; Noden and De Lahunta, Embriologia degli animali domestici, 1991), while the second to the right of it (Barone, Anatomia comparata dei mammiferi domestici, 2003). The purpose of this study was to clarified this aspect and identified the point at which the spiral loop adheres to the mesentery. Twenty-five Holstein bovine foetuses between 2.7 and 23 cm crown-rump length (CRL) were used in this study. Between 2.7 and 4.5 cm CRL (45-55 days of gestation) the ascending limb of the midgut occupies the umbilical cord. Between 4.5 and 8 cm (55-67 days) the first evidence of looping of the spiral loop is seen on the right side of the mesentery. Subsequently, the spiral loop, passing caudal to the mesentery, moves to the left side and concludes its looping forming a coil. Between 8 and 12 cm (67-85 days) the spiral loop adheres to the mesentery. Our observations, therefore, are in a condition intermediate to the two theses previously exposed. The identification of the moment in which the spiral loop adheres closely to the mesentery is particularly important in understanding the abnormalities of the colon.