Search

This paper presents a strategy for optimal manoeuvre design of multi-satellite formation flying in low Earth orbit environment, with the aim of providing a tool for mission operation design. The proposed methodology for formation flying manoeuvres foresees a continuous low-thrust control profile, to enable the operational phases. The design is performed starting from the dynamic representation described in the relative orbital elements, including the main orbital perturbations effects. It also exploits an interface with the classical radial-transversal-normal description to include the maximum delta-v limitation and the safety condition requirements. The methodology is applied to a remote sensing mission study, Formation Flying L-band Aperture Synthesis, for land and ocean application, such as a potential high-resolution Soil Moisture and Ocean Salinity (SMOS) follow-on mission, as part of a European Space Agency mission concept study. Moreover, the results are applicable to a wide range of low Earth orbit missions, exploiting a distributed system, and in particular to Formation Flying L-band Aperture Synthesis (FFLAS) as a follow-on concept to SMOS., Comment: 19 pages

The NEAM Tsunami Hazard Model 2018 (NEAMTHM18) is a probabilistic hazard model for tsunamis generated by earthquakes. It covers the coastlines of the North-eastern Atlantic, the Mediterranean, and connected seas (NEAM). NEAMTHM18 was designed as a three-phase project. The first two phases were dedicated to the model development and hazard calculations, following a formalized decision-making process based on a multiple-expert protocol. The third phase was dedicated to documentation and dissemination. The hazard assessment workflow was structured in Steps and Levels. There are four Steps: Step-1) probabilistic earthquake model; Step-2) tsunami generation and modeling in deep water; Step-3) shoaling and inundation; Step-4) hazard aggregation and uncertainty quantification. Each Step includes a different number of Levels. Level-0 always describes the input data; the other Levels describe the intermediate results needed to proceed from one Step to another. Alternative datasets and models were considered in the implementation. The epistemic hazard uncertainty was quantified through an ensemble modeling technique accounting for alternative models’ weights and yielding a distribution of hazard curves represented by the mean and various percentiles. Hazard curves were calculated at 2,343 Points of Interest (POI) distributed at an average spacing of ∼20 km. Precalculated probability maps for five maximum inundation heights (MIH) and hazard intensity maps for five average return periods (ARP) were produced from hazard curves. In the entire NEAM Region, MIHs of several meters are rare but not impossible. Considering a 2% probability of exceedance in 50 years (ARP≈2,475 years), the POIs with MIH >5 m are fewer than 1% and are all in the Mediterranean on Libya, Egypt, Cyprus, and Greece coasts. In the North-East Atlantic, POIs with MIH >3 m are on the coasts of Mauritania and Gulf of Cadiz. Overall, 30% of the POIs have MIH >1 m. NEAMTHM18 results and documentation are available through the TSUMAPS-NEAM project website (http://www.tsumaps-neam.eu/), featuring an interactive web mapper. Although the NEAMTHM18 cannot substitute in-depth analyses at local scales, it represents the first action to start local and more detailed hazard and risk assessments and contributes to designing evacuation maps for tsunami early warning. © Copyright © 2021 Basili, Brizuela, Herrero, Iqbal, Lorito, Maesano, Murphy, Perfetti, Romano, Scala, Selva, Taroni, Tiberti, Thio, Tonini, Volpe, Glimsdal, Harbitz, Løvholt, Baptista, Carrilho, Matias, Omira, Babeyko, Hoechner, Gürbüz, Pekcan, Yalçıner, Canals, Lastras, Agalos, Papadopoulos, Triantafyllou, Benchekroun, Agrebi Jaouadi, Ben Abdallah, Bouallegue, Hamdi, Oueslati, Amato, Armigliato, Behrens, Davies, Di Bucci, Dolce, Geist, Gonzalez Vida, González, Macías Sánchez, Meletti, Ozer Sozdinler, Pagani, Parsons, Polet, Power, Sørensen and Zaytsev.

Methane is a crucial energy carrier with a massive use in all sectors and a well-developed distribution and storage infrastructure. In the framework of the efforts made to address the energy transition, it is of great interest the replacement of fossil methane by its synthetic alternative, the Substitute Natural Gas, coming from renewable sources. The reactants (CO/CO2 and H2) for catalytic methanation can be obtained from different pathways involving renewable sources: they could derive, for example, from biomass-produced syngas or from generated H2, exploiting the surplus of renewable electricity to perform water electrolysis, and CO2, which can be a pure captured stream, thus giving a Carbon Capture and Utilization solution. The studies on catalytic methanation have recently been developed with the concept of sorption-enhanced reaction, using a proper sorbent material to adsorb the water produced by the reactions, in order to enhance the equilibrium conditions even at low pressures. The aim of this work was to analyze the Sorption Enhanced Methanation (SEM) in a Dual Fluidized Bed system at 300°C and 1 atm, by selecting CaO as water sorbent and using as simulator Aspen Plus®V10 software. The process was mainly analyzed under stoichiometric conditions, introducing dimensionless parameters to consider different relative quantities of CO and CO2 fed, and different amounts of CaO compared to the stoichiometric one to capture all the generated H2O. The purity of the methane is a sensitive aspect to assess, given the restrictions for injection in the grid, in particular with regard to the percentage of admissible H2. SEM results on the outlet composition showed that H2 on dry basis was never low enough to be fed directly into the grid. The undesired carbonation of CaO was found to be the main reason for this behavior. This secondary reaction seems to be able, by absorbing CO2, to shift the equilibrium of important involved reactions towards the consumption of the methane itself, and the production of H2. To fulfill the limits for injection, another kind of sorbent, not subject to carbonation and already being studied, may be selected, e.g. a zeolite, acting as molecular sieve and giving water selective adsorption. Another interesting condition to be verified may be to evaluate non-stoichiometric conditions, and in particular when H2 is the limiting reactant.

Current multistage CCU technologies using renewable electricity to yield fuels suffer from low energy efficiency and require large capital expenditures. To increase the efficiency of the whole process and reduce its cost, a possible innovative solution is represented by the combined capture and hydrogenation of CO2. The idea is to trap CO2 from a CO2-containing stream (e.g. combustion flue gases) using a dual functioning material (DFM) composed of a highly dispersed supported adsorbent which provides at the same time the CO2 storage function and methanation active element to produce CH4 upon reaction with renewable H2 [1-2]. This process is operated cyclically by alternating phases where the DFM is exposed to the flue gas and CO2 is selectively adsorbed, and phases where H2 is fed and the stored CO2 is hydrogenated to methane [2]. Notably, by eliminating a thermal swing process, the conversion of CO2 to SNG using DFMs constrains the energy input to only renewable sources (in the form of H2), thus allowing the CO2 capture and utilization processes to approach carbon neutrality while integrating more renewable energy into the grid [2]. In a highly innovative scheme aimed at the process intensification, the DFM represents a CO2 carrier that is continuously circulated from a sorption reactor to a methanation reactor and vice versa [3]. Dual interconnected fluidized bed technology appears perfectly suited to perform the chemical looping CO2 Capture and Methanation process since it allows the recirculation of DFM particles between two reactors and ensures their efficient and independent temperature control. Therefore, we set out to experimentally investigate the key features capable to boost the overall performance of DFMs based on Ru and alkali metal (oxides) supported on high surface area aluminas with suitable mechanical and attrition resistance to be used in interconnected fluidized bed reactors. The general scope is to produce synthetic methane via an innovative, renewable energy driven, catalytic looping process, demonstrating effectiveness and reduction of greenhouse gas emissions while also addressing economic, regulatory, environmental and (critical) raw material constraints, as well as socio-economic impact related to the proposed technological pathway.

According to RED II targets by 2030 the renewable energy consumption must be raised up to 32%, particularly 14% of the energy supplied for road and rail transport must be renewable. As part of renewable energy sources, residual biomass plays a significant role, because of its availability and the possibility of obtaining advanced biofuels and biochemical trough several thermochemical and biochemical processes, such as pyrolysis, gasification and aerobic digestion. The main challenge of using residual biomass is its properties variability (e.g., O/C ratio, ashes content, extractives, cellulose, hemicellulose, lignin and so on) according to type, geographic localization and seasonality. For this reason, properties and yields of the products are highly variable. Furthermore, the complexity of the processes involved in biomass valorization often makes the classical chemical-physical modelling approach very challenging. In this framework, the research community as well as the industrial sector are focusing their attention on the adoption of new provisional tools, based on advanced statistical methods, machine learning techniques and operative research techniques for decision-making support, in order to improve the sustainability utilization of the biomass resources. In particular, this work represents the first attempt to this new modelling approach, focusing its attention on the thermochemical valorization of residual biomass. The principal components analysis (PCA), which projects the original data in principal component (PC) space for assessing which input parameters have the highest score on the PC reducing the input data dimension, without losing valuable information, is used for the fast pyrolysis process. A broad database with about 450 observations is developed collecting data from scientific literature. The database includes both qualitative and quantitative information regarding main biomass characteristics (e.g., type, proximate and ultimate analysis), operative parameters (e.g., temperature, pressure, type of reactor) pyrolysis products and byproducts (e.g., yields, quality). PCA is applied to a subset of the original data considering only fast pyrolysis process, non-catalytic, in a fluidized-bed reactor with a temperature range of 450-550°C.

The development of sustainable, clean modern energy carriers has swept across the energy sector in line with the goals of moving towards low carbon economies. This has resulted in the increased utilisation of previously neglected solid organic waste resources as alternative carbon feedstocks for fuels and petrochemicals, as evidenced by more research towards valorisation of lignocellulosic and plastic waste resources. Co-pyrolysis has been identified as a potential pathway to benefit from this readily available stream of residual carbon providing a platform to produce valuable products that may fit into the different energy vector streams. Despite a lot of work being done at microscale pyrolysis to determine the synergistical potential of co-feeding, less work has been done on large scale reactors with potential for commercialisation on the impact of co-pyrolysis to improve the quality of pyrolysis oils. In this study, our focus is identifying potential synergy between devolatilization and condensation products that may occur in the presence of an inert and catalytic bed under bench scale fluidised bed conditions. The product distribution from non-catalytic pyrolysis of olive stone and polyethylene was comprised of derivatives indicative of a combination of the individual pyrolysis products i.e., oxygenated biomass derivatives plus olefinic monomers plastic derivatives. This could suggest that condensation synergy as suggested by Gunasee, et al. [1] may be the dominant process, requiring changes in operating procedure to allow for secondary reactions. For the catalytic experiments, the product distribution was shifted due to secondary reactions, however there was no conclusive information to distinguish the type of synergy that may have occurred, i.e., devolatilization/condensation synergy. There is still ongoing work on this project to try to optimise the process parameters towards increasing the interactive devolatilization synergy towards improving the quality of pyrolysis oils.

In this paper, the potential of alcohol-gasoline blends as fuels for spark-ignition engines has been evaluated. The general purpose of the work is to verify the possibility of incrementing the bio-fuels penetration in the market of transportation fuels. As it is well known, bio-mass derived fuels, in fact, could significantly reduce the CO2 emissions of energy thermal systems. The behavior of a small, turbocharged spark-ignition engine, firing with gasoline-butanol blends, has been analyzed. Analyses have been carried out by means of both experimental tests and numerical simulations. In previous works, engine main performances have been illustrated and discussed. Here, experimental tests have been carried out in order to compare the engine knock resistance and the obtainable fuel conversion efficiency when the engine is fueled by pure gasoline or gasoline-butanol blends at high load operation. Furthermore, one dimensional numerical analyses have been utilized in order to compare the engine behavior, at different operating points, when it is firing with pure gasoline or pure butanol. In general, the obtained results seem to indicate that butanol (produced by bio-masses) is a viable alternative to fossil fuels in the way of CO2 emission reduction.

Fast pyrolysis is a thermochemical conversion process that has gained increased attention over the last decade since it offers an effective way to produce valuable bio-oil as a green alternative to crude oil in the production of liquid fuels, platform chemicals and materials. A clear understanding of how the feedstock composition impacts on the distribution and quality of pyrolysis products is important for both the optimization of the process and the design of bio-oil upgrading strategies. To address this knowledge gap, the conversion of two different types of biomass (i.e., spruce wood and wheat straw) into bio-oil has been experimentally investigated and the obtained results are described in the present work. In more detail, the pyrolysis experiments were performed in a bench-scale fluidized bed reactor at 500 °C and at atmospheric pressure, using a feed particle size smaller than 1 mm and a gas residence time of about 1 s, which allowed to achieve relatively high yields of the liquid product for the two investigated feedstocks (72% for spruce wood and 44% for wheat straw). Results highlight that the biomass composition significantly affects the distribution and the composition of pyrolysis products.

In this work, the behavior of an engine running with binary and ternary mixtures of n-butanol, ethanol and gasoline has been investigated. Analyses have been performed at different engine speed both at low load and at high load. For each blend, the air to fuel ratio has been kept stoichiometric, while the spark time has been tuned in order to maximize the engine brake torque and hence the engine fuel conversion efficiency. The performance, the combustion characteristics and the pollutant emissions of the engine fueled by biofuel mixtures have been compared to those characterizing the engine running with neat gasoline. In an attempt to provide a guideline for the development of engines running with every mix of gasoline and alcohol, measurements are presented as a function of the oxygen content of the fuel. When the fuel oxygen content increases, results show that the optimal spark time must be retarded at part load while must be advanced at high load. At this operation, the maximum obtainable efficiency increases, the CO2 specific emissions decrease almost linearly together with NOx and HC specific emissions, the engine torque remains practically the same, while the brake specific fuel consumption increases.

In the last decades a potpourri of looping processes for clean utilization of fossil sources has been proposed and studied as a transient solution towards zero-emission energy. The present paper examines looping processes recently proposed and developed for both carbon oxidation/gasification and CO2 capture and transformation. Selected scientific issues associated to dynamic operation are also investigated by means of an innovative experimental technique based on a twin-bed reactor. Combustion and gasification: Chemical looping with oxygen uncoupling (CLOU) and CarboLoop processes accomplish combustion or gasification of coal and more generally of solid fuels through reiterated alternation of oxidation and desorption steps. The literature on carbon combustion generally refers to continuous operating conditions, whereas dynamical effects have not been deeply investigated. The aim of the present study is to contribute to a better understanding of the mechanism and chemistry of carbon oxidation throughout dynamic oxidizing/reducing cycles. CO2 capture: Calcium Looping (CaL) provides a feasible and robust path to accomplish carbon capture from CO2-bearing exhaust [2]. Efficiency of CaL is affected by sorbent thermal sintering (deactivation) upon iterated looping and by particle attrition/fragmentation. A less scrutinized issue is the concurrent effect of steam and SO2 in terms of sorbent availability and selective uptake. This study aims at a deeper investigation of the performance of Ca-based sorbents in ternary CO2-SO2-H2O systems. CO2 transformation: In Sorption-Enhanced Methanation the steam generated by methanation is removed from the gas phase in a catalytic bed by adding a sorbent material. CO2 methanation in combination with chemical storage, solar fuels and CO2 utilization [3] is particularly interesting. In this work an innovative configuration, based on two interconnected fluidized beds, is investigated.

Proceedings of the 42nd Meeting The Italian Section of The Combustion Institute

In this paper, the performance of a turbocharged SI engine, firing with butanol/gasoline blends, has been investigated by means of numerical simulations of the engine behavior. When engine fueling is switched from gasoline to alcohol/gasoline mixture, engine control parameters must be adapted. The main necessary modifications in the Electronic Control Unit have been highlighted in the paper. Numerical analyses have been carried out at partial load operation and at two different engine speeds (3000 and 4000 rpm). Several n-butanol/gasoline mixtures, differing for the alcohol contents, have been analyzed. Such engine performances as torque and indicated efficiency have been evaluated. Both these characteristics decrease with the alcohol contents within the mixtures. On the contrary, when the engine is fueled by neat n-butanol, torque and efficiency reach values about 2% higher than those obtained with neat gasoline. Furthermore, the optimal spark timing, for alcohol/gasoline mixture operation, must be retarded (up to 13%) in comparison with the correspondent values of the gasoline operation. In general, engine performance and operation undergo little variations when fuel supplying is switched from gasoline to alcohol/gasoline blends.

Biofuels seem to represent one of the most promising means for the limitation of the greenhouse gas emissions coming from traditional energy systems. In this paper, the performance of a “downsized” spark-ignition engine, fueled by gasoline and bio-butanol blends (20% and 40% butanol mass percentage), has been analyzed. In the first phase of this activity, the experimental tests have been carried out at operating points ranging from low to medium engine speed and load. The first investigations were aimed to assess the main differences among the different fuels in terms of output torque, thermal efficiency, combustion duration and optimal spark timing. In order to study the engine behavior in a wide range of fuel mixtures, these parameters have been evaluated for equivalence ratio values ranging from 1.25 to 0.83. The results obtained in this step show that both the engine torque and thermal efficiency slightly decrease (meanly about 4%) when the blend alcohol content increases. However, butanol increases the burning rate of lean mixtures and an interesting result is that the spark advance does not require adjustments when fueling changes from neat gasoline to bio-butanol/gasoline blends. Later, the pollutant emissions and the CO2 emissions, for both rich and lean mixtures of pure gasoline and gasoline bio-butanol blends, have been measured. In general, firing with alcohol blends, NOx and CO emissions remain quite the same, HC emissions slightly decrease while the CO2 emissions slightly increase. At the end, in order to reproduce the real world urban driving cycle, stoichiometric mixtures have been analyzed. In these conditions, the engine thermal efficiency, at given speed and torque, has been evaluated for each kind of fueling. The results obtained in these operating points have shown that the alcohol blend fueling performs an efficiency penalty less than 2 percent.

s of the papers presented at the Joint Meeting German and Italian Sections of The Combustion Institute, 41th Combustion Meeting Associazione Sezione Italiana del Combustion Institute

s of the papers presented at the 40th Combustion Meeting Associazione Sezione Italiana del Combustion Institute

1998).Since the lingual papillae of the domestic ruminant show an extreme variety of shape, webelieved it interesting to extend the study to innervation of the lingual papillae of the waterbuffalo, analyzing the morphological, structural, and immunohistochemical characteristicsof the gustatory papillae.MATERIALS AND METHODSThe study was performed on 25 water buffalo fetuses of both sexes, from 5 to 60cm inlength, and originating from a local slaughter-house. The fetus length, from the sinciput tothe tail root, was utilized as a development index. The fetuses were subdivided into fivegroups in relation to their length (5–7cm; 10–15cm; 20–25cm; 30–35cm; 40–60cm). Foreach group samples were prepared for scanning electron microscopy (SEM), transmissionelectron microscopy (TEM), light microscopy (LM), and the simple immunohistochemicalmethod.The TEM samples were treated by the usual techniques.

In the modern Vehicular Ad-hoc Networks (VANET) based systems even more applications require lot of data to be exchanged among vehicles and infrastructure entities. Due to mobility issues and unplanned events that may occurs it is important that contents should be transferred as fast as possible by taking into account consistence of the exchanged data and reliability of the connections. In order to face with these issues, in this work we propose a new transfer data protocol called Fast and Scalable Content Transfer Protocol (FSCTP). This protocol allows a data transfer by using a bidirectional channel among content suppliers and receivers exploiting several cooperative sessions. Each session will be based on User Datagram Protocol (UDP) and Transmission Control Protocol (TCP) to start and manage data transfer. Often in urban area the VANET scenario is composed of several vehicle and infrastructures points. The main idea is to exploit ad-hoc connections between vehicles to reach content suppliers. Moreover, in order to obtain a faster data transfer, more than one session is exploited to achieve a higher transfer rate. Of course it is important to manage data transfer between suppliers to avoid redundancy and resource wastages. The main goal is to instantiate a cooperative multi-session layer efficiently managed in a VANET environment exploiting the wide coverage area and avoiding common issues known in this kind of scenario. High mobility and unstable connections between nodes are some of the most common issues to address, thus a cooperative work between network, transport and application layers needs to be designed.

Comunicazione Poster

Comunicazione Poster

Comunicazione Orale

Calcium looping is a promising post-combustion technology for capturing CO2 from flue gases by using solid CaO-based sorbents (e.g. limestone). It is based on a dual fluidized bed (DFB) system that involves a carbonator - where flue gas is absorbed by CaO - and a regenerator where captured CO2 is enriched to be processed and stored. The potential reuse of spent – from repeated cycles - CaO in cement raw meal is among the advantages of the technology. This could allow substantial CO2 savings in an industry that thrives for decarbonisation. In this study, purged CaO – taken from a 200 KWth DFB pilot facility in the University of Stuttgart - was used in raw meal. The aim was to evaluate if clinker (thus cement and concrete) of acceptable quality can be produced and if any bottlenecks exist. Purged CaO was found chemically compatible with raw meal and can replace all limestone in the mix without altering the quality targets. Its elevated SO3 content (approx. 2%) however allows for approximately. 10% addition or else clogging phenomena can occur in the preheater. Practically to allow complete limestone replacement and avoid undesired process implications – in kiln systems with no by-pass installed - SO3 of the purged sorbent must be kept up to 0.3%. Trace elements were found very low, posing no concern for clinker or emissions. Sulphur was in the form of anhydrite, thus it is not expected to give rise to SOx emissions. Burnability of raw meal was improved and clinker quality was found similar to the reference case. A higher C2S content that was detected was not in expense of C3S thus no detrimental effect on early strength is anticipated. It was estimated that for every 1% of purged CaO replacing limestone, a CO2 save of 3.6 kg/tn of raw meal can be achieved. Equivalently, a plant producing 1 mil. tons of clinker/annum, can save approx. 300.000 tons of CO2 emitted.

This paper reports on the preliminary findings obtained by applying the steam-hydration technique to a spent German sorbent coming from a fluidized bed (FB) calcium looping process. The attention was focused on the regeneration of the sorbent CO2 capture capacity induced by steam hydration, and on the effect that this technique has on the attrition tendency of the reactivated material. To this end, calcium looping (before and after steam hydration) and steam-hydration tests were carried out in a lab-scale FB reactor. In particular, steam hydration of the spent sorbent was carried out at 250°C for 10 min in a 50% steam-containing atmosphere. With reference to calcium looping tests, the rate of fines generation, the sorbent particle size distribution and the CO2 capture capacity were monitored. Results highlighted the effectiveness of the steam-hydration treatment in reactivating the sorbent activity to CO2 capture of the spent sorbent, and that steam hydration brought about only a very slight increase in the sorbent attrition tendency. Results were also compared with those obtained (and previously published) under the same operating conditions and with the same sorbent, reactivated by liquid water hydration at 25°C for 10 min. The spent sorbent generated in this study, when submitted to 10 min-FB steam hydration/reactivation, showed a value of the hydration degree equal to 15%, so indicating that under the present operating conditions the onset of the chemical hydration process was observable. Though the extent of the hydration reaction was limited, the steam-hydration treatment was effective in reactivating the sorbent activity to CO2 capture: the CO2 capture capacity raised from 0.04–0.06 g/g (last carbonation before reactivation) to 0.26 g/g (first carbonation after reactivation). Elutriation results highlighted that steam hydration brought about only a very slight increase in the sorbent attrition tendency: after 3 complete calcination/carbonation cycles, the cumulative loss of elutriated fines was 1.38% for the steam-hydrated sample, while this loss was 1.59% for the raw sorbent after 4 complete cycles.

Comunicazione Poster

Disease resistance in transgenic plants has been improved, for the first time, by the insertion of a gene from a biocontrol fungus. The gene encoding a strongly antifungal endochitinase from the mycoparasitic fungus Trichoderma harzianum was transferred to tobacco and potato. High expression levels of the fungal gene were obtained in different plant tissues, which had no visible effect on plant growth and development. Substantial differences in endochitinase activity were detected among transformants. Selected transgenic lines were highly tolerant or completely resistant to the foliar pathogens Alternaria alternata , A. solani , Botrytis cinerea , and the soilborne pathogen Rhizoctonia solani . The high level and the broad spectrum of resistance obtained with a single chitinase gene from Trichoderma overcome the limited efficacy of transgenic expression in plants of chitinase genes from plants and bacteria. These results demonstrate a rich source of genes from biocontrol fungi that can be used to control diseases in plants.

A regenerable sorbent based on manganese oxides impregnated on high surface area ?-alumina and supported onto cordierite honeycomb monolith was tested for elemental mercury capture in different gas environments. Hg capture experiments were carried out in a lab-scale quartz reactor operated at temperatures from 50 °C to 350 °C, Hg concentration in the range 50-250?g/m3, and GHSV=3.6o105 h-1. The sorbent was tested in air (reference case), nitrogen and air with added CO2, CO, NO, SO2 and HCl. Results were analyzed in terms of the apparent initial Hg removal rate. In the absence of oxygen, the sorbent gradually deteriorated its performance. Both CO2 and CO moderately worsened the Hg capture performance, while NO did not show any appreciable effect. The effect of all these species appeared to be reversible, i.e. when they were removed from the gas stream, the original sorbent performance was recovered. On the other hand, SO2 adversely impacted on the sorbent performance and most importantly the Hg capture capacity was permanently deteriorated. No release of oxidized Hg was observed in tests containing the above components both during adsorption and desorption stages. When HCl was present in the gas stream the sorbent both adsorbed elemental Hg and catalyzed its heterogeneous oxidation giving an overall outstanding performance. During desorption only oxidized mercury was released.

The aim of this work was to study the hydration-reactivation behaviour of spent sorbents from a calcium looping (CaL) process. The changes of the sorbent properties induced by hydration, the regeneration of the CO2 capture capacity and the attrition tendency of the material once reused in the CaL cycle were investigated. Results suggested that the sorbent should be hydrated for times as short as possible compatible with complete chemical hydration. In fact, long hydration times bring about cramming (chemical sintering) phenomena, lower enhancement of the active porosity, increased attrition tendency and reduced reactivation.

This paper reports on a numerical simulation of the heat and mass transfer process occurring in a seawater scrubber for marine application. The aim of the work is to make a comparison with the results obtained from a previous simple model, where the liquid flow was modeled as a plug flow (the injection angle was neglected and all the droplets were assumed to be identical). A DPM (Discrete Phase Model) has been chosen for this case, where droplets trajectory, velocity and temperature is calculated as first step of the CFD simulation. A real scrubber prototype has been simulated. Preliminary results of the CFD model are presented in terms of temperature distributions for diluted and condensed phases, as well as of distributions of size and residence time of the droplets.

Six limestones and one dolomite from different European countries were tested for CO2 capture during simulated calcium looping cycles in a lab-scale fluidized bed (FB) and in a thermo-gravimetric (TG) apparatus. The FB tests were carried out under severe conditions representative of a process with calcination in an oxy-firing environment (T = 940°C, 70% CO2). The TG tests were performed with a somewhat milder calcination environment (T = 900°C, 15% CO2). Carbonation conditions were the same for the two types of experiments (T = 650°C, 15% CO2). The effect of the presence of SO2 (during both calcination and carbonation) at two different concentration levels was also studied in both devices. The aim of these experiments was to select the best sorbents for further larger scale testing, and to establish if TG testing is representative of results obtained under more realistic FB conditions, as regards CO2 capture capacity and overall ranking of the sorbents. Results showed that the CO2 capture capacity of the sorbents measured in TG tests was generally larger than that that measured in FB experiments. This was attributed to the severer calcination conditions in the latter tests, implying an increased effect of sintering. A notable exception was the dolomite sorbent, which was less subject to sintering and more prone to fragmentation during the FB tests. The presence of SO2 depressed the CO2 capture capacity of all the sorbents in both types of experiments, due to the sulfate layer formation around the particles. SEM/EDX and porosimetric analyses of the spent sorbents confirmed the above findings. Interestingly, the ranking of the sorbents towards CO2 capture was similar under FB and TG conditions and was not significantly influenced by the presence of SO2.

An assay based on electrolyte leakage (LEA) from callus tissue of Solanum spp. treated with culture filtrates of Verticillium dahliae was useful for screening eggplant genotypes for resistance to Verticillium wilt. Loss of electrolytes from the most resistant genotypes was significantly lower than that from the susceptible genotypes when callus tissue was incubated with a 10% filtrate solution of the virulent isolate 122. No difference was detected with filtrate solutions of the avirulent isolate 809 of the fungus. Among the tested genotypes, the S. melongena lines CCR3 and SM19/14 and the wild species S. torvum were the most resistant in the glasshouse tests and released the smallest amounts of electrolytes. The most susceptible cultivars, Lunga Violetta and Giant of China, produced the greatest leakage of electrolytes. LEA performed on stem segments failed to distinguish between susceptible and resistant genotypes of eggplant.