The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Fabrizio Di Gregorio - One of the best experts on this subject based on the ideXlab platform.
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a techno economic evaluation of a small scale fluidized bed gasifier for solid recovered fuel
Fuel Processing Technology, 2015Co-Authors: Umberto Arena, Fabrizio Di Gregorio, Gianfranco De Troia, Alessandro SaponaroAbstract:Abstract This paper reports a technical assessment for an Air Gasification plant for energy recovery from 5000 t/y of a solid recovered fuel (SRF). This was obtained as one of the output streams from a sorting platform of municipal solid waste, which aims to minimize the utilization of the annexed landfill. The case study analysis was based on data provided by a pilot-scale bubbling fluidized bed gasifier, having a feedstock capacity of about 70 kg/h of the obtained SRF. The tests indicate that the SRF can be converted into a syngas of valuable quality for energy applications. A plant configuration, which includes a bubbling fluidized bed reactor, a mild combustor, a 400 kWe Organic Rankine Cycle generator and an Air pollution control system, was defined and described in detail. The standard accounting items related to investment and operating costs were estimated on the basis of official manufacturer's specifications and information: they indicate an economic sustainability only in presence of an incentive tariff for energy production. A material flow analysis indicates that the implementation of the small-scale gasifier could allow a landfill volume saving of more than 10,000 m 3 /y.
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energy generation by Air Gasification of two industrial plastic wastes in a pilot scale fluidized bed reactor
Energy, 2014Co-Authors: Umberto Arena, Fabrizio Di GregorioAbstract:Two plastic wastes obtained as co-products from an industrial process were fed in a pilot-scale bubbling fluidized bed gasifier, having an internal diameter of 0.38 m and a maximum thermal output of about 400 kW. The experimental runs were carried out by reaching a condition of thermal and chemical steady state under values of equivalence ratio ranging from 0.2 to 0.3. Olivine, a neo-silicate of Fe and Mg, already tested as a good catalyst for tar removal during Gasification of polyolefin plastic wastes, was used as bed material. The results provide the complete composition of the syngas, including the tar, particulate and acid/basic gas contents as well as the chemical and physical characterization of the bed material and entrained fines. The Gasification process appears technically feasible, yielding a producer gas of valuable quality for energy applications in an appropriate plant configuration. On the other hand, under the experimental conditions tested, olivine particles show a strongly reduced catalytic activity in all the runs. The differences in the Gasification behaviour of the two industrial plastics are explained on the basis of the structure and composition of the wastes, taking also into account the results of a combined material and substance flow analysis.
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Gasification of a solid recovered fuel in a pilot scale fluidized bed reactor
Fuel, 2014Co-Authors: Umberto Arena, Fabrizio Di GregorioAbstract:Abstract The paper investigates the technical feasibility of an Air Gasification process of a Solid Recovered Fuel (SRF) obtained from municipal solid waste. A pilot scale bubbling fluidized bed gasifier, having a feedstock capacity of about 70 kg/h and a maximum thermal output of about 400 kW, provided the experimental data: the complete composition of the syngas (including the tar, particulate and acid/basic gas contents), the chemical and physical characterization of the bed material and that of entrained fines collected at the cyclone. The experimental runs were carried out by reaching a condition of thermal and chemical steady state under values of equivalence ratio ranging from 0.25 to 0.33. The results indicate that the selected SRF can be conveniently gasified, yielding a syngas of valuable quality for energy applications. The rather high content of tar in the syngas indicates that the more appropriate plant configuration should be that of a “thermal gasifier”, with the direct combustion of the syngas in a burner ad hoc designed, coupled with an adequate energy-conversion device.
Bayu Prabowo - One of the best experts on this subject based on the ideXlab platform.
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co2 recycling biomass Gasification system for highly efficient and carbon negative power generation
Applied Energy, 2015Co-Authors: Bayu Prabowo, Muhammad Aziz, Herri Susanto, Kentaro Umeki, Kunio YoshikawaAbstract:This study explored the feasibility of biomass CO2 Gasification as an effective method for implementing the concept of a carbon-negative power system through bioenergy with carbon capturing and storage. A CO2-recycling biomass Gasification system was developed and examined using the thermal equilibrium model. Sensitivity analysis was performed by varying the gasifier temperature from 750 to 950°C, and the turbine inlet temperature (TIT) and turbine exit temperature (TET) of the gas turbine from 1000 to 1200°C and from 900 to 1000°C, respectively. The gasifier efficiency was increased by an increase in the CO2 recycling ratio with the more significant trend shown at the lower gasifier temperature. The turbine efficiency decreased as the CO2 recycling ratio to the gasifier increased over a certain limit, a ratio of 0.55 in most cases. A pressure ratio of 2.3 was optimum in terms of turbine efficiency. Under the examined conditions, the optimum conditions for gaining the highest system efficiency, 39.03%, were a recycling ratio of 0.55 and a TET and TIT of 1000 and 1200°C respectively. The proposed system had 7.57% higher efficiency and exhausted 299.15g CO2/kWh less CO2 emissions than conventional Air Gasification. Combined with carbon capturing and storage, the system potentially generates carbon-negative power generation with intensity of around 1.55-kgCO2/kgwet-biomass and a maximum efficiency penalty of 6.89%.
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co2 recycling biomass Gasification system for highly efficient and carbon negative power generation
Applied Energy, 2015Co-Authors: Bayu Prabowo, Muhammad Aziz, Herri Susanto, Kentaro Umeki, Kunio YoshikawaAbstract:This study explored the feasibility of biomass CO2 Gasification as an effective method for implementing the concept of a carbon-negative power system through bioenergy with carbon capturing and storage. A CO2-recycling biomass Gasification system was developed and examined using the thermal equilibrium model. Sensitivity analysis was performed by varying the gasifier temperature from 750 to 950°C, and the turbine inlet temperature (TIT) and turbine exit temperature (TET) of the gas turbine from 1000 to 1200°C and from 900 to 1000°C, respectively. The gasifier efficiency was increased by an increase in the CO2 recycling ratio with the more significant trend shown at the lower gasifier temperature. The turbine efficiency decreased as the CO2 recycling ratio to the gasifier increased over a certain limit, a ratio of 0.55 in most cases. A pressure ratio of 2.3 was optimum in terms of turbine efficiency. Under the examined conditions, the optimum conditions for gaining the highest system efficiency, 39.03%, were a recycling ratio of 0.55 and a TET and TIT of 1000 and 1200°C respectively. The proposed system had 7.57% higher efficiency and exhausted 299.15g CO2/kWh less CO2 emissions than conventional Air Gasification. Combined with carbon capturing and storage, the system potentially generates carbon-negative power generation with intensity of around 1.55-kgCO2/kgwet-biomass and a maximum efficiency penalty of 6.89%.
Umberto Arena - One of the best experts on this subject based on the ideXlab platform.
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a techno economic evaluation of a small scale fluidized bed gasifier for solid recovered fuel
Fuel Processing Technology, 2015Co-Authors: Umberto Arena, Fabrizio Di Gregorio, Gianfranco De Troia, Alessandro SaponaroAbstract:Abstract This paper reports a technical assessment for an Air Gasification plant for energy recovery from 5000 t/y of a solid recovered fuel (SRF). This was obtained as one of the output streams from a sorting platform of municipal solid waste, which aims to minimize the utilization of the annexed landfill. The case study analysis was based on data provided by a pilot-scale bubbling fluidized bed gasifier, having a feedstock capacity of about 70 kg/h of the obtained SRF. The tests indicate that the SRF can be converted into a syngas of valuable quality for energy applications. A plant configuration, which includes a bubbling fluidized bed reactor, a mild combustor, a 400 kWe Organic Rankine Cycle generator and an Air pollution control system, was defined and described in detail. The standard accounting items related to investment and operating costs were estimated on the basis of official manufacturer's specifications and information: they indicate an economic sustainability only in presence of an incentive tariff for energy production. A material flow analysis indicates that the implementation of the small-scale gasifier could allow a landfill volume saving of more than 10,000 m 3 /y.
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energy generation by Air Gasification of two industrial plastic wastes in a pilot scale fluidized bed reactor
Energy, 2014Co-Authors: Umberto Arena, Fabrizio Di GregorioAbstract:Two plastic wastes obtained as co-products from an industrial process were fed in a pilot-scale bubbling fluidized bed gasifier, having an internal diameter of 0.38 m and a maximum thermal output of about 400 kW. The experimental runs were carried out by reaching a condition of thermal and chemical steady state under values of equivalence ratio ranging from 0.2 to 0.3. Olivine, a neo-silicate of Fe and Mg, already tested as a good catalyst for tar removal during Gasification of polyolefin plastic wastes, was used as bed material. The results provide the complete composition of the syngas, including the tar, particulate and acid/basic gas contents as well as the chemical and physical characterization of the bed material and entrained fines. The Gasification process appears technically feasible, yielding a producer gas of valuable quality for energy applications in an appropriate plant configuration. On the other hand, under the experimental conditions tested, olivine particles show a strongly reduced catalytic activity in all the runs. The differences in the Gasification behaviour of the two industrial plastics are explained on the basis of the structure and composition of the wastes, taking also into account the results of a combined material and substance flow analysis.
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Gasification of a solid recovered fuel in a pilot scale fluidized bed reactor
Fuel, 2014Co-Authors: Umberto Arena, Fabrizio Di GregorioAbstract:Abstract The paper investigates the technical feasibility of an Air Gasification process of a Solid Recovered Fuel (SRF) obtained from municipal solid waste. A pilot scale bubbling fluidized bed gasifier, having a feedstock capacity of about 70 kg/h and a maximum thermal output of about 400 kW, provided the experimental data: the complete composition of the syngas (including the tar, particulate and acid/basic gas contents), the chemical and physical characterization of the bed material and that of entrained fines collected at the cyclone. The experimental runs were carried out by reaching a condition of thermal and chemical steady state under values of equivalence ratio ranging from 0.25 to 0.33. The results indicate that the selected SRF can be conveniently gasified, yielding a syngas of valuable quality for energy applications. The rather high content of tar in the syngas indicates that the more appropriate plant configuration should be that of a “thermal gasifier”, with the direct combustion of the syngas in a burner ad hoc designed, coupled with an adequate energy-conversion device.
A Zabaniotou - One of the best experts on this subject based on the ideXlab platform.
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Contribution to Circular Economy options of mixed agricultural wastes management: Coupling anaerobic digestion with Gasification for enhanced energy and material recovery
Journal of Cleaner Production, 2019Co-Authors: N Antoniou, Florian Monlau, Cecilia Sambusiti, E Ficara, Abdellatif Barakat, A ZabaniotouAbstract:Anaerobic digestion (AD) is an established process for the treatment of organic wastes and the production of renewable energy. However, high amounts of digestate produced by AD plants require enhancement for further use. This study investigates a conceptual model for the digestate enhancement by using a downstream Gasification. It is based on a ‘systemic approach’ considering the interactions of every contributing process into the dual system. The digestate was provided by an Italian AD plant, that treats mixed agricultural wastes of pig manure (43%), cow manure (20%), maize and triticale silages (25%), and cereal bran (12%). Digestate Air Gasification experiments were conducted, in a downdraft fixed-bed reactor, at temperature range from 750 °C to 850 °C, with λ varying from 0.14 to 0.34. Results have shown that Gasification of digestate at 850 °C with λ = 0.24, increased producer gas yield (65.5 wt %), and its LHV (2.88 MJ Nm−3). The gas is classified as medium heating value fuel, suitable to generate electricity of 971 kWhel day−1 to enhance the AD plant's economic viability. A carbonaceous material rich in macronutrients (P, K, Ca, Mg) was produced, with R50 = 0.48, suitable for carbon sequestration. The study offers a resource closed loop approach of converting AD digestate into energy and soil fertilizer. Useful suggestions for policy makers and business can be drawn.
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valorization of cotton stalks by fast pyrolysis and fixed bed Air Gasification for syngas production as precursor of second generation biofuels and sustainable agriculture
Bioresource Technology, 2009Co-Authors: Efthymios Kantarelis, A ZabaniotouAbstract:Abstract In the present study, the potential of cotton stalks utilization for H 2 and syngas production with respect to CO 2 mitigation, by means of thermochemical conversion (pyrolysis and Gasification) was investigated. Pyrolysis was conducted at temperature range of 400–760 °C and the main parametric study concerned the effect of temperature on pyrolysis product distribution. Atmospheric pressure, Air Gasification at 750–950 °C for various λ (0.02–0.07) was also studied. Experimental results showed that high temperature favors gas production in both processes; while low λ Gasification gave high gas yield. Syngas (CO and H 2 ) was increased with temperature, while CO 2 followed an opposite trend. By pyrolysis, higher H 2 concentration in the produced gas (∼39% v/v) was achieved and at the same time lower amounts of CO 2 produced, compared to Air Gasification.
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low temperature Gasification of olive kernels in a 5 kw fluidized bed reactor for h2 rich producer gas
International Journal of Hydrogen Energy, 2008Co-Authors: Vassiliki Skoulou, G Koufodimos, Zissis Samaras, A ZabaniotouAbstract:Abstract Air Gasification of olive kernels in a 5 kW bench scale, bubbling fluidized bed gasifier, aimed at H 2 enrichment of the producer gas, was the target of this study. The effects of reactor temperature ( T = 750–850 °C) and equivalence ratio (ER = 0.2–0.4), representing the under stoichiometric amount of Air inserted into the reactor to that necessary for complete combustion, on producer gas quality were determined. The experimental results revealed that producer gas H 2 content increased at the temperature of T = 750 °C and ER = 0.2, resembling the high-temperature pyrolysis conditions that favour H 2 and CO production. Further increase in ER deteriorated producer gas quality, decreased H 2 content and favoured CO 2 , thus lowering producer gas heating value. The data obtained from several experiments indicate that olive kernels produced a medium heating value gas (LHV = 6.54 MJ/Nm 3 ) at 750 °C and ER = 0.2, while H 2 and CO production were maximized at the same conditions (H 2 : 24%vv, CO: 14.3%vv).
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mathematical modelling and simulation approaches of agricultural residues Air Gasification in a bubbling fluidized bed reactor
Chemical Engineering Journal, 2008Co-Authors: D A Nemtsov, A ZabaniotouAbstract:Agricultural residues (agro-biomass) can produce energy by thermochemical conversion. Gasification is becoming one of the best clean technologies for power production. Thermochemical process of Gasification sets free the solid fuel inherent energy and converts the solid phase into a mixture of gases (producer gas or syngas) that carries a percentage of this energy. Fluidized bed reactors may be used for biomass Gasification offering many advantages such as: (1) the superior mixing properties and (2) the enhanced heat transfer rates between the gas and the particles as well as between the particles and the heat exchanger surfaces. In this paper Gasification process applied to agricultural residues is reviewed by means of modelling. Description of various stages of the biomass Gasification in a fluidized bed is made and the whole spectrum of problems from the processes in an individual biomass particle (drying, pyrolysis, fragmentation and charl burning) to the global mass transfer and chemical processes in a fluidized bed reactor and freeboard is presented. The paper discusses also the specific problems arising from using agricultural residues as raw material and recommends further experimental studies necessary for process optimisation and for scale up. Extensive investigation of Gasification plant behaviour depending on various operating parameters is always required in order to support the optimisation procedure and mathematical models are helpful to reduce the temporal and financial efforts.
Jesús Arauzo - One of the best experts on this subject based on the ideXlab platform.
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influence of gas residence time and Air ratio on the Air Gasification of dried sewage sludge in a bubbling fluidised bed
Fuel, 2006Co-Authors: Joan J Manya, Alberto Gonzalo, Javier Abrego, J L Sanchez, Jesús ArauzoAbstract:Abstract Because little information is available about sewage sludge Gasification in a bubbling fluidised bed (BFB), further experiments are required to quantify the power generation potential of dried sewage sludge (DSS) as well as to evaluate the optimum conditions for its Gasification. In this work, the influence of the bed height on the process was experimentally determined using a laboratory-scale BFB reactor. The Gasification tests were performed at different values of equivalence ratio (λ) and at two values of constant bed height (150 and 300 mm). Attention was focused on the effect of increasing bed height on the gas composition, average cold gas efficiency, and product distribution. Results obtained in this study show that a bed height increase improves the efficiency of the DSS Gasification process. This fact could be explained because the high ash content of DSS represents an obstacle to the gas diffusion.
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Air Gasification of dried sewage sludge in a fluidized bed effect of the operating conditions and in bed use of alumina
Energy & Fuels, 2005Co-Authors: Joan J Manya, J L Sanchez, And Alberto Gonzalo, Jesús ArauzoAbstract:Sewage sludge has recently become a particularly important problem all over the world because of its harmful impact on the environment. The consequent need to develop alternative processes for the use of dried sewage sludge for energy purposes, such as Gasification, requires experimental tests in order to quantify the potential energy power of the sludge, as well as to evaluate the optimum conditions for its Gasification. There is, however, little information available. In this study, the Gasification with Air of dried sewage sludge was experimentally investigated using a bubbling fluidized bed. Attention was focused on the influence of the temperature (750−850 °C), the equivalence ratio (25−35%), and the fluidizing velocity (5, 8, and 11 times the value of umf) on the product yields, gas composition, thermal efficiency, and tar content. The results obtained show the potential for using sewage sludge Gasification with Air as an option for energy recovery and waste treatment. However, the high tar yield ob...
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scale up of downdraft moving bed gasifiers 25 300 kg h design experimental aspects and results
Bioresource Technology, 1994Co-Authors: P Garciabacaicoa, Jesús Arauzo, Rafael Bilbao, M L SalvadorAbstract:Abstract Two installations with different biomass processing capacities (25–50 and 200–300 kg/h) were designed and constructed for Air Gasification of lignocellulosic biomass. This paper describes both installations as well as the experimental procedure. The influence of operating conditions on the amount and quality of products was determined. The results obtained from processing forestry waste are analysed. Values above 90% for mass conversion efficiency and over 70% for cold gas efficiency were reached.