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Aims: The aim of this work was to evaluate the fertilizing effect of three anaerobic co-digestates on the growth of the herbaceous plant Lolium rigidum. Methods: Nine treatments, combining different nutritional solutions (organic and inorganic) and number of fertilizations (one or two) were evaluated. Organic nutritive solution: plants grown with different olive mill solid waste (OMSW) -microalgae co-digestates: 75% OMSW-25% Raphidocelis subcapitata, volatile solids (VS) basis (OMSW-Rs); 50% OMSW- 50% Chlamydomonas Reinhardtii, VS basis (OMSW-Chl); and 75% OMSW-25% Secenedesmus quadricauda, VS basis (OMSW-Sq). Inorganic nutritive solution (INS): plants grown with inorganic Hoagland nutrient solution at 50%. After 60 days of experimentation, biometric and nutritional characteristics and photosynthetic activity were measured. Results: The results showed a favourable growth, development and nutritional quality of L. rigidum plants when digestates obtained from the anaerobic co-digestion of OMSW-microalgae are used as organic nutritional solutions as opposed to INS ones. The highest total biomass of L. rigidum was obtained with the treatments that involved two fertilizations. No inhibition due to excess nutrients was observed. A higher root/shoot ratio was achieved with the digestates of OMSW-Rs and OMSW-Ch as compared to that obtained with OMSW-Sq (F = 17.23 p ≤ 0.001). The nitrogen shoot biomass obtained after the organic treatments with the above-mentioned co-digestates was higher than that obtained after the inorganic treatment. Net photosynthesis rates did not present differences in the co-digestates treatments, being equal or superior to the INS treatments. Conclusions: The use of the anaerobic co-digestates from OMSW-microalgae can be considered a viable and promising alternative to inorganic fertilization. [ABSTRACT FROM AUTHOR]

The biomass valorisation of the invasive brown alga Rugulopteryx okamurae (Dictyotales, Phaeophyceae) is key to curbing the expansion of this invasive macroalga which is generating tonnes of biomass on southern Spain beaches. As a feasible alternative for the biomass management, anaerobic co-digestion is proposed in this study. Although the anaerobic digestion of macroalgae barely produced 177 mL of CH4 g−1 VS, the co-digestion with a C-rich substrate, such as the olive mill solid waste (OMSW, the main waste derived from the two-phase olive oil manufacturing process), improved the anaerobic digestion process. The mixture improved not only the methane yield, but also its biodegradability. The highest biodegradability was found in the mixture 1 R. okamurae—1 OMSW, which improved the biodegradability of the macroalgae by 12.9% and 38.1% for the OMSW. The highest methane yield was observed for the mixture 1 R. okamurae—3 OMSW, improving the methane production of macroalgae alone by 157% and the OMSW methane production by 8.6%. Two mathematical models were used to fit the experimental data of methane production time with the aim of assessing the processes and obtaining the kinetic constants of the anaerobic co-digestion of different combination of R. okamurae and OMSW and both substrates independently. First-order kinetic and the transference function models allowed for appropriately fitting the experimental results of methane production with digestion time. The specific rate constant, k (first-order model) for the mixture 1 R. okamurae- 1.5 OMSW, was 5.1 and 1.3 times higher than that obtained for the mono-digestion of single OMSW and the macroalga, respectively. In the same way, the transference function model revealed that the maximum methane production rate (Rmax) was also found for the mixture 1 R. okamurae—1.5 OMSW (30.4 mL CH4 g−1 VS day−1), which was 1.6 and 2.2 times higher than the corresponding to the mono-digestions of the single OMSW and sole R. okamurae (18.9 and 13.6 mL CH4 g−1 VS day−1), respectively. [ABSTRACT FROM AUTHOR]

The aim of the present work was to compare the mesophilic anaerobic digestion of untreated olive mill solid waste (OMSW), soft hydrothermal pre-treated OMSW (SHP OMSW), and a co-digestion mixture of 95% OMSW and 5% microalga Dunaliella salina (co-OMSW). During the co-digestion experiment, the volatile fatty acid accumulation decreased in comparison with that obtained for OMSW and SHP OMSW, reducing the slight inhibition observed during the OMSW and SHP OMSW experiments. Final values of methane yield of 380 ± 1 mL CH4 g−1 VSadded for the OMSW, 424 ± 2 mL CH4 g−1 VSadded for the SHP OMSW, and 491 ± 1 mL CH4 g−1 VSadded for the co-OMSW were determined. Two mathematical models, first-order kinetics and modified Gompertz model, were employed to fit the experimental data with the aim of elucidating the anaerobic biodegradation and obtain the kinetic constants. Both models allowed for adequately fitting the experimental results of methane production with time. The kinetic constant, k, of the first-order model increased by 12% for the co-OMSW compared with the values achieved for OMSW and SHP OMSW. The modified Gompertz model revealed that the maximum methane production rate, Rm, for the co-OMSW and SHP OMSW increased by 34.7% and 10.3% compared with the value obtained for OMSW. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD) is one of the most efficient processes for treating agri-food waste in order to obtain renewable energy. Olive mill solid waste (OMSW) is the main residue from the two-phase olive oil manufacturing process; it has a high organic content and high C/N ratio, which hinders its AD, giving low methane yield. In the present study, a microalga, Scenedesmus quadricauda, was used as co-substrate for the AD of OMSW to compensate for its nitrogen deficiency. The robustness and the high growth rate of S. quadricauda make this microalga a potential source of nitrogen to co-digest with carbon-rich substrates. Different co-digestion mixtures of OMSW-microalgae and the single substrates were tested. For all co-digestion mixtures, the alkalinity value at the end of the experiment remained below 4889 ± 245 mg CaCO3 L−1 and pH in the range of 7.50–7.67 indicating stability and good process performance. Results showed the highest methane yield (461 mL CH4 STP g−1 VS added) for the co-digestion mixture 75% OMSW-25% S. quadricauda (C/N = 25.3), which was 104 and 23% higher than that obtained from the single microalga (C/N = 5.6) and OMSW (C/N = 31.9), respectively. No ammonia inhibition was detected despite the high protein content of the microalgae. The transference function model allowed for adequately fitting the experimental results of methane production with time in the anaerobic experiments. The highest maximum methane production rate, Rm, among the different co-digestion mixtures assayed was obtained for the mixture 75% OMSW-25% S. quadricauda with a value of 89 mL CH4 g−1 VS day−1. [ABSTRACT FROM AUTHOR]

Olive oil washing water derived from the two-phase manufacturing process was assessed as an electron donor in a bio-electrochemical system (BES) operating at 35 ºC. Start-up was carried out by using acetate as a substrate for the BES, reaching a potential of around +680 mV. After day 54, BES was fed with olive oil washing water. The degradation of olive oil washing water in the BES generated a maximum voltage potential of around +520 mV and a Chemical Oxygen Demand (COD) removal efficiency of 41%. However, subsequent loads produced a decrease in the COD removal, while current and power density diminished greatly. The deterioration of these parameters could be a consequence of the accumulation of recalcitrant or inhibitory compounds, such as phenols. These results demonstrated that the use of olive oil washing water as an electron donor in a BES is feasible, although it has to be further investigated in order to make it more suitable for a real application. [ABSTRACT FROM AUTHOR]

Introducción El autoinyectable permite al propio combatiente o a un compañero, en cualquier situación y lugar, el poder administrar por vía intramuscular antídotos que contrarresten los efectos frente agentes neurotóxicos. Por ello el CEMILFARDEF, invierte y apuesta por la I+d+i de nuevos productos de interés estratégico militar, un claro ejemplo es el desarrollo que se ha llevado a cabo para la fabricación del AUTOINYECTABLE DE INSTRUCCIÓN DEF. Objetivos. Presentar el nuevo dispositivo disponible para la instrucción del combatiente en el uso del autoinyectable en centros de formación NRBQ dentro del ámbito de las Fuerzas Armadas. Material y Métodos: El AUTOINYECTABLE DE INSTRUCCIÓN DEF está constituido por: - Un cilindro exterior de poliamida, cuya parte interna es estanca y la parte exterior va precintada en todo su conjunto con una etiqueta informativa (Sleever). - Un muelle de acero inoxidable, es el elemento mecánico capaz de hacer disparar el dispositivo. - Una jeringa que acoge la solución inyectable, compuesta por vidrio, caucho y juntas de estanqueidad. - La solución inyectable contenida son 3 ml de agua. Resultados: El AUTOINYECTABLE DE INSTRUCCIÓN DEF es el mismo dispositivo que el AUTOINYECTABLE ATROPINA PRALIDOXIMA DEF, las únicas diferencias son: composición, ausencia de aguja intramuscular y el color del Sleever. Conclusiones. En una situación de estrés por ataque real, la rapidez de respuesta se puede ver gravemente disminuida. Por ello es de gran relevancia que todo el personal que vaya a estar potencialmente expuesto a agentes neurotóxicos y tenga que administrarse un autoinyectable, disponga de una instrucción previa para la correcta administración de un dispositivo de estas características. [ABSTRACT FROM AUTHOR]