Biomass Gasification and Tar Reforming in a Two-stage Reactor

Abstract 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 CH4, CO and H2 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 H2. Ce-promoted bimetallic Ni-Co catalyst was tested and compared with Ni catalyst, both supported on γ-Al2O3

Contrasting fault fluids along high-angle faults: a case study from Southern Apennines (Italy)

This work focuses on two fault-controlled deposits, the Atella and Rapolla travertines, which are associated with high-angle extensional faults of the Bradano Trough, southern Apennines (Italy). The Atella travertine is along a NW-SE striking, deep-seated extensional fault, already described in literature, which crosscuts both Apulian carbonates and the overlying foredeep basin in fill. The Rapolla travertine is on top of a NE-SW striking, shallow-seated fault, here described for the first time, which is interpreted as a tear fault associated with a shallow thrust displacing only the foredeep basin infill. The results of structural, sedimentological, mineralogical, and C and O isotope analyses are here reported and discussed to assess the provenance of mineralizing fluids, and to evaluate the control exerted by the aforementioned extensional faults on deep, mantle-derived and shallow, meteoric fluids. Sedimentological analysis is consistent with five lithofacies in the studied travertines, which likely formed in a typical lacustrine depositional environment. Mineralogical analysis show that travertines mainly consist of calcite, and minor quartz, feldspar and clay minerals, indicative of a terrigenous supply during travertine precipitation. The isotope signature of the two studied travertines shows different provenance for the mineralizing fluids. At the Atella site, the δ13C PDB values range between +5.2 and +5.7 ‰ and the δ18O PDB values between −9.0 and − 7.3 ‰ , which are consistent with a mantle-derived CO2component in the fluid. In contrast, at the Rapolla site the δ13C PDB values vary from −2.7 to +1.5 ‰ and the δ18O PDB values from −6.8 to − 5.4 ‰ , suggesting a mixed CO2 source with both biogenic-derived and mantle-derived fluids. The results of structural analyses conducted along the footwall damage zone of the fault exposed at the Rapolla site, show that the whole damage zone, in which fractures and joints likely channeled the mixed fluids, acted as a distributed conduit for both fault-parallel and cross-fault fluid migratio

Carbon dioxide reforming of tar during biomass gasification.

The energy demand increase and the necessity to contain CO2 emissions lead to a growing interest on renewable and CO2 free energy sources. Gasification has been identified as a key technology to enhance the environmental tolerability of low quality fuels such as biomass. The principal problem related with the use of biomass in gasification processes is the high quantity of tar released during the pyrolysis step of this fuel. Tar can account up to 50% of the total volatiles and contains a great part of the biomass energy. For this reason it is necessary to recover the tar and to transform it in combustible lighter gas species such as methane, carbon monoxide and hydrogen by means of catalytic processes. Another important issue is to lower the carbon dioxide content of the produced gas in order to increase its calorific value. The dry reforming represents an interesting solution. In this work the dry reforming of tar in a two stages bench scale reactor is proposed. In the proposed dry reforming process the tar reacts with the carbon dioxide released during the biomass pyrolysis to form carbon monoxide and hydrogen. It is thus possible to recover the tar energy converting it into CO and H2 and to lower the syngas dilution using the CO2 as a reagent. The dry reforming is a catalytic process and one of the major issues is the deactivation of the catalysts due to carbon deposition. The solution of this problem is very important in the case of tar dry reforming because of its high C/H ratio, which intensifies this phenomenon. Nickel has been extensively studied for the dry reforming but it is known that it suffers from carbon deposition. In this work Ce-promoted bimetallic Ni-Co catalysts with two different supports were tested. Copyright © 2014,AIDIC Servizi S.r.l

Carbon dioxide reforming of tar during biomass gasification

The energy demand increase and the necessity to contain CO2 emissions lead to a growing interest on renewable and CO2 free energy sources. Gasification has been identified as a key technology to enhance the environmental tolerability of low quality fuels such as biomass. The principal problem related with the use of biomass in gasification processes is the high quantity of tar released during the pyrolysis step of this fuel. Tar can account up to 50% of the total volatiles and contains a great part of the biomass energy. For this reason it is necessary to recover the tar and to transform it in combustible lighter gas species such as methane, carbon monoxide and hydrogen by means of catalytic processes. Another important issue is to lower the carbon dioxide content of the produced gas in order to increase its calorific value. The dry reforming represents an interesting solution. In this work the dry reforming of tar in a two stages bench scale reactor is proposed. In the proposed dry reforming process the tar reacts with the carbon dioxide released during the biomass pyrolysis to form carbon monoxide and hydrogen. It is thus possible to recover the tar energy converting it into CO and H2 and to lower the syngas dilution using the CO2 as a reagent. The dry reforming is a catalytic process and one of the major issues is the deactivation of the catalysts due to carbon deposition. The solution of this problem is very important in the case of tar dry reforming because of its high C/H ratio, which intensifies this phenomenon. Nickel has been extensively studied for the dry reforming but it is known that it suffers from carbon deposition. In this work Ce-promoted bimetallic Ni-Co catalysts with two different supports were tested. Copyright © 2014,AIDIC Servizi S.r.l

Intestinal parasites in immigrants in the city of Naples (southern Italy)

The present study was aimed at carrying out a cross-sectional copromicroscopic survey of helminths and intestinal protozoa in immigrants in Naples (southern Italy). Between October 2008 and November 2009, a total of 514 immigrants were tested comparing the FLOTAC dual technique and the ethyl acetate concentration technique. Combined results of the two techniques served as a diagnostic ‘gold’ standard and revealed an overall prevalence of parasitic infections of 61.9% (318/514). The ethyl acetate concentration technique detected a low number of positive results (49.0%) and this was confirmed for each helminth/protozoa species detected. Among helminths, Trichuris trichiura (3.9%), hookworms (3.7%) and Ascaris lumbricoides (1.4%) were the most prevalent. Strongyloides stercoralis (0.4%), Enterobius vermicularis (0.4%), Schistosoma mansoni (1.0%), Hymenolepis nana (1.6%) and Taenia spp. (0.2%) were also found, as well as zoonotic helminths, as Trichostrongylus spp. (0.8%) and Dicrocoelium dendriticum (0.8%). As regard to pathogenic protozoa, Blastocystis hominis was the most commonly detected (52.7%), followed by Entamoeba histolytica/Entamoeba dispar/Entamoeba moshkovskii (11.9%) and Giardia duodenalis (4.5%). Several issues concerning diagnosis, epidemiology and public health impact of parasitic infections in immigrants are offered for discussion. In conclusion, the present paper pointed out the need of better diagnosis and cure of the immigrants population in order to improve access to health care of this neglected and marginalised population group, for its own protection and care