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Gasification is one of the most promising technologies to convert low quality fuels into more valuable ones. The main problem in the use of biomass in gasification processes is the high amount of tar released in the pyrolysis step. It is thus necessary to recover the tar and to transform it in lighter combustible gas species such as CH 4 , CO and H 2 by means of catalytic processes. In this work the gasification of olive husk is performed in order to produce a high quality syngas, composed mainly of carbon monoxide and hydrogen, using an innovative laboratory scale plant composed of a unique reactor divided into three sections. The first section is dedicated to the pyrolysis, the second to the gasification of char produced during pyrolysis and the third to the catalytic reforming of tar. In the reformer two catalysts were tested: a CeO 2 promoted bimetallic Ni–Co catalyst and a Ni catalyst, both supported on γ-Al 2 O 3 . This plant design allows one to minimize the heat dispersion enhancing the energy efficiency of the unit. [ABSTRACT FROM AUTHOR]

Gasification is recognized as one of the most promising technologies to convert low quality fuels into more valuable ones. The principal problem related with the use of biomass in gasification processes is the high amount of tar released during the pyrolysis step. It is thus necessary to recover tar and to transform it in lighter combustible gas species such as CH 4 , CO and H 2 . In this work the experimental results of a medium industrial scale plant fed with olive husk and having a capacity of 250 kWt are presented. The gasifier is composed by a up-draft reactor which is followed by a secondary fixed bed reactor filled with alluminium oxide spheres having high porosity dedicated to the tar conversion reactions. The syngas is then used to feed an internal combustion engine with a production of 60 kWe. [ABSTRACT FROM AUTHOR]

Gasification is recognized as one of the most promising technologies to convert low quality fuels into more valuable ones. The principal problem related with the use of biomass in gasification processes is the high amount of tar released during the pyrolysis step. It is thus necessary to recover the tar and to transform it in lighter combustible gas species such as CH 4 , CO and H 2 by means of catalytic processes. In this work the gasification of olive husk is performed in order to produce a high quality syngas, composed principally by carbon monoxide and hydrogen, using an innovative laboratory scale two-stage reactor. The first stage is used for gasification and the second for catalytic reforming. It is thus possible to recover the tar energy converting it into CO and H 2 . Ce-promoted bimetallic Ni-Co catalyst was tested and compared with Ni catalyst, both supported on γ-Al 2 O 3 . [ABSTRACT FROM AUTHOR]

Abstract: Aim of the present work is quantifying the mechanical stress generated by some major process equipment used in massive microalgae culturing plants (centrifugal and air-lift pumps, and nozzles) and highlighting its effects on the microalgal population. Two microalgal species were used as test cases: Chlorella vulgaris (unicellular) and Scenedesmus dimorphus 1237 (colonial). The evaluation of the shear effect on algal growth was carried out through measurement of absorbance, photosynthetic activity (oxygen evolution) and variable chlorophyll fluorescence. Cell aggregate development/breakage was effectuated by visual inspection and light scattering. The use of centrifugal pumps for culture recycling strongly affected the growth of C. vulgaris, while nozzles effects were confined to aggregate breakage of S. dimorphus. The analysis of experimental data is supported by the consideration of hydrodynamic stress calculated by: shear rate, shear stress, stress volumes/times, energy dissipation rates, and turbulence microscale size. [Copyright &y& Elsevier]