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A Circular Waste Management alternative is considered in this paper in which a complete ash valorization process is proposed for an Integrated Gasification with Combined Cycle fly ash, trying to extract maximum value from this waste before it is discarded. In the paper, germanium, a scarce resource vital in our modern society, is first extracted from fly ash using water, with an extraction yield of 85%, and subsequently, the leached fly ash is used in the manufacture of fire-resistant boards containing 60% ash, thereby avoiding its disposal in a landfill. The potential environmental impact caused by the two stages of the process was analyzed, and the final effluent was considered to achieve a zero-discharge objective. This paper contributes to the development of a more sustainable management alternative for an industrial waste produced in increased amounts and provides the basis for a symbiotic coupling relationship among various industrial sectors.

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Antecedentes y objetivo: El bloqueo del plano de la fascia clavipectoral se ha descrito como una estrategia anestésica y analgésica para la cirugía de osteosíntesis de las fracturas del tercio medio clavicular. Pero, hasta el momento, solo hay publicados casos aislados. El objetivo de este estudio fue evaluar la eficacia anestésica y analgésica de este nuevo abordaje en cirugía de fractura de tercio medio clavicular en una amplia serie de casos. Material y métodos: Estudio descriptivo, observacional, de 50 pacientes intervenidos para osteosíntesis de fractura de tercio medio clavicular mediante un bloqueo del plano de la fascia clavipectoral asociado a un bloqueo del nervio supraclavicular. Como objetivo primario se evaluó el dolor mediante escala visual análoga en el postoperatorio inmediato y a las 6-12-24h. Como objetivos secundarios se midieron el grado de sedación intraoperatorio, el consumo de morfínicos perioperatorio, la necesidad de analgesia de rescate, la anestesia general no planificada, la presencia de bloqueo motor y sensitivo, y el diagnóstico de parálisis diafragmática. Resultados: El dolor postoperatorio fue de 1,04 (DE=1,26) en el postoperatorio inmediato; 1,24 (DE=1,42) a las 6h; 1,34 (DE=1,92) a las 12h, y 0,96 (DE=1,29) a las 24h. La dosis total de fentanilo intraoperatorio promedio fue de 0,88μg/kg. Durante el postoperatorio, 9 pacientes (18%) solicitaron analgesia de rescate. No hubo reconversiones a anestesia general, ni se objetivaron bloqueo motor o sensitivo de la extremidad superior ni parálisis diafragmática. Conclusiones: Nuestra serie apoya la eficacia anestésica y analgésica del bloqueo del plano de la fascia clavipectoral para la osteosíntesis de fracturas de tercio medio clavicular.(AU)

Background and objective: Clavipectoral fascia plane block has been described as an anaesthetic and analgesic strategy for osteosynthesis of midclavicular fractures. However, to date, only isolated cases have been published. The aim of this study was to evaluate the anaesthetic and analgesic efficacy of this new approach in midclavicular fracture surgery in a large case series. Material and methods: Descriptive, observational study of 50 patients undergoing osteosynthesis of middle third clavicular fracture who received clavipectoral fascia plane block associated with supraclavicular nerve block. The primary objective was to assess pain on a visual analog scale in the immediate postoperative period, and at 6, 12 and 24h. Secondary objectives were to determine the degree of intraoperative sedation, perioperative morphine consumption, need for rescue analgesia, unplanned general anaesthesia, presence of motor and sensory blockade, and diagnosis of diaphragmatic paralysis. Results: Postoperative pain was 1.04 (SD=1.26) in the immediate postoperative period; 1.24 (SD=1.42) at 6h; 1.34 (SD=1.92) at 12h, and 0.96 (SD=1.29) at 24h. Mean total intraoperative fentanyl dose was 0.88μg/kg. Postoperatively, 9 patients (18%) requested rescue analgesia. There were no conversions to general anaesthesia, no motor or sensory blockade of upper extremities, and no hemidiaphragmatic paralysis. Conclusions: Our series supports the anaesthetic and analgesic efficacy of clavipectoral fascia plane block for osteosynthesis of midclavicular fractures.(AU)

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Antecedentes y objetivo: El bloqueo del plano de la fascia clavipectoral se ha descrito como una estrategia anestésica y analgésica para la cirugía de osteosíntesis de las fracturas del tercio medio clavicular. Pero, hasta el momento, solo hay publicados casos aislados. El objetivo de este estudio fue evaluar la eficacia anestésica y analgésica de este nuevo abordaje en cirugía de fractura de tercio medio clavicular en una amplia serie de casos. Material y métodos: Estudio descriptivo, observacional, de 50 pacientes intervenidos para osteosíntesis de fractura de tercio medio clavicular mediante un bloqueo del plano de la fascia clavipectoral asociado a un bloqueo del nervio supraclavicular. Como objetivo primario se evaluó el dolor mediante escala visual análoga en el postoperatorio inmediato y a las 6-12-24h. Como objetivos secundarios se midieron el grado de sedación intraoperatorio, el consumo de morfínicos perioperatorio, la necesidad de analgesia de rescate, la anestesia general no planificada, la presencia de bloqueo motor y sensitivo, y el diagnóstico de parálisis diafragmática. Resultados: El dolor postoperatorio fue de 1,04 (DE=1,26) en el postoperatorio inmediato; 1,24 (DE=1,42) a las 6h; 1,34 (DE=1,92) a las 12h, y 0,96 (DE=1,29) a las 24h. La dosis total de fentanilo intraoperatorio promedio fue de 0,88μg/kg. Durante el postoperatorio, 9 pacientes (18%) solicitaron analgesia de rescate. No hubo reconversiones a anestesia general, ni se objetivaron bloqueo motor o sensitivo de la extremidad superior ni parálisis diafragmática. Conclusiones: Nuestra serie apoya la eficacia anestésica y analgésica del bloqueo del plano de la fascia clavipectoral para la osteosíntesis de fracturas de tercio medio clavicular.(AU)

Background and objective: Clavipectoral fascia plane block has been described as an anaesthetic and analgesic strategy for osteosynthesis of midclavicular fractures. However, to date, only isolated cases have been published. The aim of this study was to evaluate the anaesthetic and analgesic efficacy of this new approach in midclavicular fracture surgery in a large case series. Material and methods: Descriptive, observational study of 50 patients undergoing osteosynthesis of middle third clavicular fracture who received clavipectoral fascia plane block associated with supraclavicular nerve block. The primary objective was to assess pain on a visual analog scale in the immediate postoperative period, and at 6, 12 and 24h. Secondary objectives were to determine the degree of intraoperative sedation, perioperative morphine consumption, need for rescue analgesia, unplanned general anaesthesia, presence of motor and sensory blockade, and diagnosis of diaphragmatic paralysis. Results: Postoperative pain was 1.04 (SD=1.26) in the immediate postoperative period; 1.24 (SD=1.42) at 6h; 1.34 (SD=1.92) at 12h, and 0.96 (SD=1.29) at 24h. Mean total intraoperative fentanyl dose was 0.88μg/kg. Postoperatively, 9 patients (18%) requested rescue analgesia. There were no conversions to general anaesthesia, no motor or sensory blockade of upper extremities, and no hemidiaphragmatic paralysis. Conclusions: Our series supports the anaesthetic and analgesic efficacy of clavipectoral fascia plane block for osteosynthesis of midclavicular fractures.(AU)

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BACKGROUND AND OBJECTIVE: Clavipectoral fascia plane block has been described as an anaesthetic and analgesic strategy for osteosynthesis of midclavicular fractures. However, to date, only isolated cases have been published. The aim of this study was to evaluate the anaesthetic and analgesic efficacy of this new approach in midclavicular fracture surgery in a large case series. MATERIAL AND METHODS: Descriptive, observational study of 50 patients undergoing osteosynthesis of middle third clavicular fracture who received CPB block associated with supraclavicular nerve block. The primary objective was to assess pain on a VAS scale in the immediate postoperative period, and at 6, 12 and 24h. Secondary objectives were to determine the degree of intraoperative sedation, perioperative morphine consumption, need for rescue analgesia, unplanned general anaesthesia, presence of motor and sensory blockade, and diagnosis of diaphragmatic paralysis. RESULTS: Postoperative pain was 1.04 (SD=1.26) in the immediate postoperative period; 1.24 (SD=1.42) at 6h; 1.34 (SD=1.92) at 12h; and 0.96 (SD=1.29) at 24h. Mean total intraoperative fentanyl dose was 0.88µg/kg. Postoperatively, nine patients (18%) requested rescue analgesia. There were no conversions to general anaesthesia, no motor or sensory blockade of upper extremities, and no hemidiaphragmatic paralysis. CONCLUSIONS: Our series supports the anaesthetic and analgesic efficacy of CPB block for osteosynthesis of midclavicular fractures.

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The productive sector must incorporate waste into traditional materials in order to grow sustainably. In Galicia (Spain) alone, the canning industry produces over 150,000 metric tons of seashell waste per year. Most of this waste is still disposed of in landfills or open fields due to the lack of a technically feasible, environmentally sustainable, and economically profitable recycling alternative. This paper aims to study the feasibility of a new recycling alternative for seashell waste from industrial canning, based on the production of fireproof material suitable for construction use. The waste was pre-treated in order to remove salts and remaining organic matter and reduce particle size. According to international standards, physical, mechanical, and insulating properties were assessed for four compositions: 0, 40, 60 and 80% of gypsum substituted with pre-treated seashell waste. Results showed that substitution of up 60% gypsum was technically feasible. A Life-Cycle Assessment and a preliminary production cost analysis were performed by analysing a recycling case in Galicia. The case study found that 40-60% gypsum substitution obtained an environmental impact reduction of 0.4%-59% for 13 of the 18 impact categories considered compared with 0% substitution. Increases in the other 5 categories were analysed due to aquatic emissions released in the waste pre-treatment washing process. The locations of the fireproof material production facility and the waste source were a key factor. Production costs could be reduced by 20-31% by using 40-60% gypsum substituted with seashell wastes.

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More and more by-products are being used in certain materials, especially in the construction industry. Natural construction materials contain amounts of heavy metals and radionuclides, but when by-products are used in these kinds of materials, this could lead to a growth in their concentrations and have a negative impact on public health.In this paper, red mud was used as a raw material (as a clay substitute) to manufacture fired bricks. Physical, mechanical, radiological and heavy metal leaching properties of fired bricks with a replacement ratio of up to 80 wt% of clay to red mud are discussed. In addition, the effect of different sintering temperatures (1173K and 1373K) was analyzed, and results showed that the higher the temperature produced, the higher the mechanical strength.To environmentally characterize materials, they were subjected to two different leaching tests: a batch test for raw materials and a monolithic test for the bricks, respectively. The results obtained were compared with the limits stated for several heavy metals by the European Landfill Directive. Results showed that red mud gives leachate concentration values for Cr higher than the limits stated for non-hazardous by-products. Bricks do not exhibit the same problem in the samples containing a high RM proportion and manufactured at a low sintering temperature (1173K), although in the case of V, a high concentration is observed.The contents of radionuclides such as Ra-220, Th-232 and K-40 of the final construction materials were analyzed and compared with different indexes. This paper indicates the maximum amounts of RM that can be used to replace clay for the manufacture of fired bricks without environmental risk.

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This paper presents an experimental analysis on a new board composed of gypsum and fly ashes from coal combustion, which are mutually compatible. Physical and mechanical properties, sound absorption coefficient, thermal properties and leaching test have been obtained. The mechanical properties showed similar values to other commercial products. As far as the acoustic insulation characteristics are concerned, sound absorption coefficients of 0.3 and 0.8 were found. The board presents a low thermal conductivity and a fire resistance higher than 50 min (for 4 cm of thickness). The leaching of trace elements was below the leaching limit values. These boards can be considered as suitable to be used in building applications as partitions.

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Gypsum from power plant flue gas desulphurization units (FGD gypsum) is a combustion by-product produced in high quantities. In this paper, gypsum panels composed of 100% FGD gypsum from two power plants have been subjected to different physico-chemical (density, pH, humidity), mechanical (flexural and compressive strength, surface hardness, impact resistance), fire resistance and environmental tests (leaching and radioactivity). The results obtained have been compared with the requirements established in some European standards for commercial gypsum and other standards for similar products. In addition, the panels manufactured have been compared with commercial gypsum panels in order to determine the recycling possibilities of this kind of material in this application.

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Treatment of municipal solid waste (MSW) landfill leachate generally results in low percentages of nutrient removal due to the high concentration and accumulation of refractory compounds. For this reason, individual physical, chemical and biological processes have been used for the treatment of raw landfill leachate and sometimes for the mixture of domestic wastewater and landfill leachate. In this work, the possibility of treating landfill leachate was tested in a bench-scale pilot plant by a two-step method combining adsorption and coagulation-flocculation. Zeolite synthesized from coal fly ash, a by-product of coal-fired power stations, was used in this study both as a decantation aid reagent and as an adsorbent of COD and NH4-N. The coagulation-flocculation step was performed by the use of aluminium sulphate and a polyelectrolyte (ACTIPOL A-401). The leachate was collected directly from a storage unit of the organic fraction of MSW, before it was composted. For this reason the raw leachate was diluted before treatment. The sludge was recirculated to enhance the removal efficiency of nutrients as well as to optimize flocculant saving and to decrease sludge production. The results showed that it is possible to remove 43%, 53% and 82% of COD, NH4-N, and suspended solids, respectively. Therefore, this method may be an alternative for ammonium removal, as well as a suitable pre- or post-treatment step, in combination with other processes in order to meet regulatory limits.

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