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![Comparison between Air, steam, oxygen gasification processes [95]](profile/Khaled-Al-Attab/publication/364248014/figure/tbl1/AS:11431281095599652@1667959885234/Comparison-between-Air-steam-oxygen-gasification-processes-95_Q320.jpg)
This article summarizes various biomass gasification methods and explains their advantages and disadvantages. First, theoretical aspects of gasification and the variety in reactor designs are overviewed. Despite the eminent effect of reactor design on gas product quality, gasification agents remain the dominant factor that determines the gas compos...
Contexts in source publication
Context 1
... this design, the gasifying agent (air, steam etc.) is supplied into the gasifier from the bottom side via a grate, and biomass is supplied into the gasifier from the top side. The gasification agent passes upwards towards the biomass feeding level while it is converted into producer gas, hence the name updraft as shown in Figure 2(a). While biomass feed at the top of the gasifier drops by gravity down to the pyrolysis zone. ...
Context 2
... the updraft configuration, producer gas is not allowed to exit the gasifier from the top, thus, it is pushed to the bottom of the gasifier, hence the name downdraft. Downdraft gasifiers consist of four separate zones from top to bottom including drying zone followed by pyrolysis zone, oxidation zone at the throat, and lastly reduction zone below the throat as shown in Figure 2(b). The producer gas leaves the upper middle zone and descends to the lower middle zone, pushing it via the throat. ...
Context 3
... fuel feeding port is similar in all fixed bed designs at the top due to the absence of mechanical means to move biomass other than the natural drop by gravity. On the other hand, air inlet port is located at one side of the gasifier and producer gas is released from the opposite side in a crossflow manner across the gasifier as shown in Figure 2(c). The air enters at the hot combustion zone where most of it is consumed to generate the needed thermal power while the rest is passed horizontally to perform reduction reactions while pyrolysis and drying are higher in the vessel [62]. ...
Citations
... Biomass gasification stands as a versatile and sustainable method for clean energy generation, with various approaches, such as steam gasification, demonstrating efficacy in hydrogen production [47,48]. Particularly noteworthy is catalytic steam gasification utilizing calcium oxide ( ), which exhibits the capacity to yield high-purity hydrogen through simultaneous 2 absorption and catalytic action [49]. ...
As the world shifts towards sustainable energy sources, incorporating hydrogen into renewable energy systems emerges as a critical pathway. This thorough analysis delves deeply into the various facets of hydrogen integration, exploring its potential to revolutionize the energy landscape. Drawing upon recent advancements and research findings, the review examines the production, storage, and utilization of hydrogen within renewable energy frameworks. Key topics include electrolysis methods, storage technologies, and diverse applications spanning transportation, residential sectors, and industry. Furthermore, the review examines the obstacles and prospects linked with hydrogen integration, shedding light on policy frameworks, economic implications, and technological innovations driving its adoption. By offering insights into the multifaceted role of hydrogen, this review aims to inform researchers, stakeholders, and policymakers about the transformative potential of integrating green hydrogen into renewable energy systems for a sustainable future.
... Biomass gasification, on the other hand, facilitates the utilization of solid biomass more efficiently as it converts it into attainable gaseous fuel form known as producer gas (PG) that can be used directly in IC engine and gas turbine applications. The gasification performance and PG quality are strongly dependent on temperature, gasification agents (air, steam, CO2 and oxygen), feedstock, and types of gasifiers [8]. Wide range of feedstocks such as hazelnut shells, wood waste from furniture, wood chips and charcoal were investigated in literatures [9][10][11]. ...
... Therefore, steam is proposed as it is more affordable and does not cause N2 dilution in PG while increasing gas quality and higher heating value. The main challenge, however, is that steam requires an external heating source to maintain the reactor temperature as the reaction is heavenly endothermic in nature [8]. For small lab-scale experimental steam gasification, heat is commonly supplied from heater bands surrounding tube reactors with small diameters to ensure efficient heat supply for the reaction [8]. ...
... The main challenge, however, is that steam requires an external heating source to maintain the reactor temperature as the reaction is heavenly endothermic in nature [8]. For small lab-scale experimental steam gasification, heat is commonly supplied from heater bands surrounding tube reactors with small diameters to ensure efficient heat supply for the reaction [8]. To further enhance heat transfer from the heater jacket to the fuel, molten blast furnace slag was tested as the heat carrier and shown good heat transfer which enhanced H2 production from the steam gasifier [18]. ...
This study presents experimental analysis of biomass air-steam gasification for the enhancement of H2 production in producer gas (PG). Wood pellets which are widely available in Malaysia are used in this investigation. A pilot scale downdraft gasifier based on new three-layers annular reactor design was implemented to produce hydrogen enriched PG. The reactor is initially heated using hot flue gas from LPG combustion which is switched to PG when the reactor reaches stable operation. The effect of steam to biomass (S/B) ratio from 1.1 to 1.5 on PG quality in terms of gas composition, HHV and tar contamination is studied. Maximum H2 production of 27.7% was achieved at optimum air flow rate of 75 LPM and S/B ratio of 1.2. At the optimum air flow rate, HHV and tar contamination in PG where in the range of 5.06 - 6.08 MJ/Nm3 and 187 - 30mg/m3, respectively.
Facing the challenges of environmental sustainability and energy security caused by anthropogenic carbon emissions, there is a need to adopt cleaner energy generation technologies, leveraging Colombia's existing national resources. In this context, hydrogen emerges as a promising source of renewable energy. Therefore, this project explores the use of a blend of residual lignocellulosic biomass as raw material for hydrogen production through gasification for energy purposes. Initially, a screening of residual lignocellulosic biomass in the study region was conducted, a blend was selected, and a simulation of the synthesis gas production process was carried out prospectively using Aspen Plus Dynamics® software. The results revealed that, by using the selected biomass blend, a synthesis gas with a hydrogen molar fraction of 38.7% and an ER of 0.19 was obtained. According to sensitivity analyses, the optimal parameters identified to achieve this hydrogen concentration were: gasification temperature of 707°C, oxygen flows of 484 kg/h, steam at 420 kg/h, and gasification pressure of 1 atm. These findings support the potential of the studied lignocellulosic biomass blend as an alternative for hydrogen production, while also offering an opportunity for the valorization of lignocellulosic residual biomass.
Biomass conversion using air gasification suffers from the high N2 gas dilution. Using steam as gasifying agent eliminates this issue, but heat must be supplied efficiently using external sources. This study investigated biomass steam gasification in a new annular reactor design with a gas heating jacket. This experimental study used two steam injection configurations: bottom and top to evaluate the effect of gasification temperature and steam to biomass (S/B) ratio on H2% using wood pellets. Temperature varied in the range of 300–600 °C for bottom injector, while S/B varied from 1.7 to 2.6. Peak H2% was 27.7% and higher heating value (HHV) of gas was 7 MJ/Nm3. Using top injector enhanced the heat transfer which elevated the temperature range (700–950 °C) and reduced S/B ratio in the range of 1.3–2.2, achieving H2% of 44% at the optimum steam flow rate of 30 g/min with HHV of 12.7 MJ/Nm3. Tar contamination was reduced from 13.6 g/m3 to 7.4 g/m3 with the increase of S/B. The effect of different fuels including coconut shells charcoal (CSC), palm kernel shells (PKS), and Empty fruit bunch (EFB) on H2% was also investigated. H2% was 47.7% for CSC, followed by 46.3% for PKS and 44.7% for EFB.
