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The aim of this work was to evaluate the feasibility of the use of different industrial and agricultural wastes as reactive materials in Permeable Reactive Barriers (PRB) for Acid Mine Drainage (AMD) remediation. Sugar foam (SF), paper mill sludge (PMS), drinking water sludge (DWS) and olive mill waste (OMW) were evaluated in terms of pH neutralization and metal removal from AMD. Laboratory batch tests and continuous pilot scale up-flow columns containing 82% of Volcanic Slag (VS), as porous fill material, and 18% w/w of one of the industrial and agricultural wastes previously indicated, were tested. From the batch tests it was observed that the reactive material presenting the best results were the SF and the PMS. The results obtained in all the PRB were accurately described by a pseudo-first order model, presenting coefficient of determination higher than 0.96 in all the cases. During the continuous operation of the PRB, the porosity and hydraulic retention time (HRT) of most of the up-flow columns strongly decreased due to chemical precipitation and biofilm growth. The SF presented a significant number of fine particles that were washed out by the liquid flow, generating an effluent with very high total suspended solid concentration. Despite SF was the material with the highest alkalinity potential, the reduction of the HRT limited its neutralization and metal removal capacity. PMS and DWS presented the best pollutant removal yields in the continuous operation of the PRB, ranging from 55 to 99% and 55-95% (except in the case of the Mn), respectively. These results allowed the metal removal from the AMD. Additionally, these wastes presented very good biological sulphate reduction. Based on these results, the use of PMS and DWS as reactive material in PRB would allow to simultaneously valorise the industrial waste, which is very interesting within the circular economy framework, and to remove metals from the AMD by means of a low-cost and environmentally sustainable procedure.

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INTRODUCTION: Pheochromocytoma is an infrequent neuroendocrine tumor, originated from neural crest cells. 10% of them are extra adrenal, located at sympathetic nodules and are known as paragangliomas. The most common place is the Zuckerkandl organ, 10 to 26% are malign and has a mortality around de 26% of the cases. CASE REPORT: We present two cases of teenagers with Zuckerkandl's organ paraganglioma, who debut with high blood pressure, diaphoresis and dyspnea. Complete tumor resection was performed in both cases, during which they presented hipertensive crisis and, after vascular pedicle ligation, hypotension. CONCLUSIONS: Zuckerkandl's organ paraganglioma is a rare pathology in pediatric population, therefore represents an important diagnostic and therapeutic challenge. Surgery differs from other tumors because of catecholamine secretion that produces hemodynamic changes and demands prompt and accurate management from surgeon and anesthetist.

INTRODUCCION: El feocromocitoma es un tumor neuroendocrino infrecuente. El 10% son extraadrenales en los ganglios simpáticos, conocidos como paragangliomas. El sitio más común es el órgano de Zuckerkandl. Son malignos en un 10 a 26% con una mortalidad del 26%. REPORTE DE CASOS: Presentamos dos casos de paraganglioma del órgano de Zuckerkandl en adolescentes, que debutan con hipertensión arterial, diaforesis y disnea. Se realizó resección completa del tumor; durante ambas cirugías presentaron crisis hipertensiva y posterior a la ligadura del pedículo vascular del tumor presentaron hipotensión, con normalización progresiva de las cifras tensionales en el postoperatorio. CONCLUSIONES: El paraganglioma del órgano de Zuckerkandl es una patología infrecuente en la población pediátrica, representa un importante reto diagnóstico y terapéutico. La cirugía difiere de las de otros tumores ya que la secreción de catecolaminas genera cambios hemodinámicos transoperatorios que exigen al cirujano y anestesiólogo un manejo rápido, eficaz y oportuno.

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Introducción: El feocromocitoma es un tumor neuroendocrino infrecuente. El 10% son extraadrenales en los ganglios simpáticos, conocidos como paragangliomas(1,2). El sitio más común es el órgano de Zuckerkandl. Son malignos en un 10 a 26%(4) con una mortalidad del 26%(5). Reporte de casos: Presentamos dos casos de paraganglioma del órgano de Zuckerkandl en adolescentes, que debutan con hipertensión arterial, diaforesis y disnea. Se realizó resección completa del tumor; durante ambas cirugías presentaron crisis hipertensiva y posterior a la ligadura del pedículo vascular del tumor presentaron hipotensión, con normalización progresiva de las cifras tensionales en el postoperatorio. Conclusiones: El paraganglioma del órgano de Zuckerkandl es una patología infrecuente en la población pediátrica, representa un importante reto diagnóstico y terapéutico. La cirugía difiere de las de otros tumores ya que la secreción de catecolaminas genera cambios hemodinámicos transoperatorios que exigen al cirujano y anestesiólogo un manejo rápido, eficaz y oportuno

Introduction: Pheochromocytoma is an infrequent neuroendocrine tumor, originated from neural crest cells. 10% of them are extra adrenal, located at sympathetic nodules and are known as paragangliomas(1,2). The most common place is the Zuckerkandl organ, 10 to 26% are malign(4) and has a mortality around de 26% of the cases(5). Case report: We present two cases of teenagers with Zuckerkandl’s organ paraganglioma, who debut with high blood pressure, diaphoresis and dyspnea. Complete tumor resection was performed in both cases, during which they presented hipertensive crisis and, after vascular pedicle ligation, hypotension. Conclusions: Zuckerkandl’s organ paraganglioma is a rare pathology in pediatric population, therefore represents an important diagnostic and therapeutic challenge. Surgery differs from other tumors because of catecholamine secretion that produces hemodynamic changes and demands prompt and accurate management from surgeon and anesthetist

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This paper studies the simulation of carbon degradation in pilot scale solid waste composting processes using first-order kinetic models previously calibrated by laboratory experiments at different temperatures. Different solid biowastes (olive mill waste, winery waste, sewage sludge and reed biomass) were used. Three mixtures were prepared from combinations of the materials listed above, and they were used in both the laboratory kinetic experiments and the pilot scale composting experiments. Lab experiments were conducted in small reactors with temperature (T) control and forced aeration of the solid mixture. Each biowaste mixture was treated at four different temperatures, 25, 40, 50 and 60 °C, with controlled moisture; the carbon (C) concentration of the samples was measured weekly. Two different kinetic models were used to fit the carbon mineralisation curves: the 2C model, which considers two organic fractions (biodegradable and non-biodegradable), and the 3C model, which considers three fractions (easily biodegradable, slowly biodegradable and non-biodegradable). In both cases, the kinetic rate constants were calculated by mathematical fitting. The influence of temperature on the rate constants was also studied for both models using a T-dependent equation. The theoretical k(T) curves showed classical shapes, and the temperatures for optimum k values and thermal inactivation were obtained. Once the C degradation rate constants and their T dependence equations were available, it was possible to simulate the evolution of C degradation in an actual pilot scale rotary drum composting process under varying temperatures and using the same biowaste mixtures. The comparison between the theoretical profiles and the experimental data showed that the thermophilic stage could be accurately simulated; however, errors and lower levels of model accuracy occurred when the maturation stage was simulated. The simulation was valid for all of the viewed biowaste mixtures. The 2C and 3C simulation profiles were quite similar in all cases for much of the process duration; the differences between the profiles only occurred after the end of the thermophilic stage. It was concluded that the 2C model would be only valid for shorter experimental periods, until the readily biodegradable carbon fraction was removed, while the 3C model reproduced the subsequent degradation in the maturation stage more closely.

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