Environmental Valorization of Rice Waste as Adsorbent Material for the Removal of Nitrates from Water

An innovative water-treatment process consisting in reducing the nitrate concentration by using an active silica filter obtained from ashes produced during rice-straw thermal treatment has been developed by the LIFE LIBERNITRATE project. A life-cycle assessment (LCA) was carried out to evaluate the environmental impacts of this innovative process, from the production of ashes and extraction and activation of silica to the water treatment. These results were compared to the environmental impact derived from the use of bottled water, instead of tap water, where traditional water treatments (i.e., reverse osmosis) may not be available due to the high installation and operating costs. The comparison showed that the proposed innovative process could contribute to reducing the environmental impact in almost all analyzed impact categories (from 20% for photochemical oxidation to 90% for abiotic depletion) with respect to the use of bottled water. In addition, if conveniently optimized (for example reducing the amount of active silica used per day), the innovative process could further reduce the ecological footprint and be more eco-friendly than the use of bottled water and could be applied to treating water in small towns where reverse osmosis may not be installed. The LCA proved that the innovative process could contribute to reducing the environmental impact of water-treatment technologies resulting in lower environmental indicators with respect to the use of bottled water

Analysis and Comparison of Equations-of-State with p-ρ-T Experimental Data for CO2 and CO2-Mixture Pipeline Transport

Abstract Transport is an important feature of the CCS process as the CO2 quality requested by pipelines may influence the choice of the capture technology and its limit performance requirements. So, the knowledge of the thermodynamic properties of CO2-mixtures has an important role, however a suitable equation of state under the appropriate conditions for pipeline transport has not been clearly defined yet. In this paper different equations of state for predicting densities of CO2 and CO2 mixtures have been analyzed and compared with experimental data found in literature or obtained by authors performing specific laboratory p-ρ-T measurements

The effective oxidation pressure of indium-oxygen system

A theoretical model on oxygen transport at the surface of liquid metals has been validated by dynamic surface tension measurements performed on liquid Indium as test metal. The oxygen contamination conditions have been obtained at different oxygen partial pressures under both low total pressure (Knudsen regime) and inert atmospheric pressure (Fick regime) conditions, confirming that an oxide removal regime occurs under an oxygen partial pressure much higher than the equilibrium one (the "Effective Oxidation Pressure"). Experimental results are reported which give a further insight on the relative importance of the various processes due to the oxygen mass transport between the liquid metal and the gas phase. The critical aspects involved in surface tension measurements of liquid metals, related to the problem of liquid metal-oxygen interactions, are also underlined

CO2-mixture properties for pipeline transportation in the CCS process

Transport is an essential feature of the CCS process as the CO2 quality required for transport may influence the choice of the capture technology and impose limits on the performance requirements. Therefore, to design CO2 transport networks, it is important to have an accurate knowledge of the thermodynamic properties of CO2-mixtures. In this paper the results of different EOS (both cubic equations as Peng-Robinson or Redlich-Kwong-Soave and non-analytical equations as Benedict-Webb-Rubin- Starling, Lee-Kesler or GERG model) have been compared with P-ρ-T experimental data obtained by the authors. The Lee-Kesler equation and the GERG model showed a good prediction of CO2-mixture density in the working conditions of the pipeline transport. Finally, simulations of pipelines that transport pure CO2 and CO2-mixtures have been performed and discussed

On The Gasification of Torrefied Japanese Cedar to Maximise the Production of Hydrogen

Hydrogen, H2, is likely to become the key renewable energy carrier for the future. Thermochemical conversion of biomass can be applied to produce H2 involving a variety of conversion technologies, including gasification, that produce a mix of synthesis gas, H2 and CO. It is of paramount importance thus having a consolidated, efficient, versatile and clean technology to produce H2 in a sustainable and continuous manner contributing to current energy policies. For this work, a bench-scale batch gasifier located at the Tokyo Institute of Technology, Tokyo Tech, was used for the production of syngas from the torrefied woody biomass. These data were inputs for the development of an hybrid model for the prediction of the composition of the producer gas. The time-depending data obtained in the semi-batch gasifier process was composed of three regions (pyrolysis, oxidation and reduction zones) in which recurrent neural networks were combined with physical-based models, whose parameters were conveniently tuned to fit the experimental data

Sensitivity Analysis and Validation of a Two Fluid Method (TFM) model for a Spouted Bed

This work was funded through the LIFE LIBERNITRATE project (LIFE16 ENV/ES/000419) in the framework of the LIFE+ funding programme. EA and AMF acknowledge the traineeship Erasmus+ grant for Laura Ong.Peer reviewedPostprin

Deoxygenation of non-edible vegetable oil to produce hydrocarbons over Mg-Al mixed oxides

none7noopenRomero, Max; Pizzi, Andrea; Toscano, Giuseppe; Casazza, Alessandro Alberto; Busca, Guido; Bosio, Barbara; Arato, ElisabettaRomero, Max; Pizzi, Andrea; Toscano, Giuseppe; Casazza, Alessandro Alberto; Busca, Guido; Bosio, Barbara; Arato, Elisabett

Comparative Study for the Energy Valorisation of Rice Straw

The termal behaviour of rice straw when submitted to combustion and pyrolisis reactions was studied for the present work. Thermogravimetric analysis simulated these reactions and an accurate methodology evaluated its suitability and design parameters for its use in energy valorisation processes.Moliner, C.; Bosio, B.; Arato, E.; Ribes Greus, MD. (2014). Comparative Study for the Energy Valorisation of Rice Straw. Chemical Engineering Transactions. 37:241-246. doi:10.3303/CET1437041S2412463

Caracterización fluidodinámica de un reactor Spouted Bed para su uso en procesos de gasificación alimentados con paja de arroz

El uso de biomasa como alimento en procesos de obtención de energía constituye una de las alternativas para contribuir al desarrollo de tecnologías energéticas de naturaleza renovable. Entre los diferentes tipos de biomasa, los residuos agrícolas emergen como una fuente de alimento apta para procesos termo-químicos. Estos residuos presentan en muchas ocasiones grandes dificultades en su gestión y acaban convirtiéndose en problemas ambientales y sociales. Este es el caso de la paja de arroz, para la que el método de eliminación más común (30%) sigue siendo su quema incontrolada, con el aumento en emisiones de CO2 que ello conlleva y el daño que representa. Los procesos de valorización energética, y en concreto las transformaciones termo-químicas, son comúnmente utilizadas en la actualidad para convertir biomasa en combustibles de características adecuadas. Entre ellas, la gasificación se presenta como una de las tecnologías con más proyección [1] y los reactores de tipo Spouted Bed (SB) se sitúan como una herramienta adecuada para llevar a cabo dichos procesos. La caracterización fluido dinámica del reactor es un elemento esencial para la obtención de los mejores rendimientos y eficiencias en los procesos de conversión termo-química. Por ello, el presente trabajo tiene como objetivo evaluar los parámetros fluido dinámicos característicos (perfiles de velocidad y presión) de un reactor Spouted Bed de base cuadrada. Para ello, se han realizado pruebas a baja temperatura utilizando paja de arroz como material de alimento y sílice como material inerte. Estos resultados se han comparado con los obtenidos mediante un modelo fluido dinámico, desarrollado con el software comercial Fluent©, considerando una aproximación euleriana en la que tanto el gas como los sólidos son considerados como medios continuos y las interacciones entre partículas son definidas mediante relaciones de clausura.Los autores agradecen la colaboración del Prof. Giorgio Rovero y el Dr. Massimo Curti y por la disponibilidad que han mostrado para la realización de las pruebas en sus laboratorios en el Politecnico de Torino (Italia)