The effect of steam on air gasification of mechanically activated coal in a flow reactor

A combined steam-gas plant with in-cycle steam gasification of coal and hot gas purification is considered as a promising technology for increasing the efficiency of energy production with simultaneous reduction in environmental impact. To intensify steam-air gasification, mechanical activation of fuel is used; it consists in high-stress grinding in a mill-disintegrator. The supply of steam to the gasifier allows an increase in reactivity of fuel, suppression of sorbent decomposition in the unit of hot desulfurization, reduction in the steam load on the shift reactor, increase in useful external work of gas turbine expansion, reduction in nitrogen oxide formation, and general increase in the efficiency and ecological compatibility of energy generation. On the other hand, a significant amount of steam can deteriorate the heat balance and efficiency of the gasifier. In this work, the influence of the steam/fuel ratio on steam-air gasification of mechanically activated Kuznetsk coal in a flow reactor was studied experimentally. The excess air coefficient was maintained constant and equal to 0.51, which corresponded to a temperature at the reactor outlet of about 1100?C. When steam was supplied, the fuel and air flow rates were adjusted to ensure a constant gas-dynamic regime. To evaluate the obtained regimes, the heat and material balances were compiled. A positive effect of steam on characteristics of the gasification process was revealed. For the studied coal, the maximum degree of coal conversion and the calorific value of synthesis gas are achieved with a steam/fuel ratio of about 0.4 kg/kg.

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A parametric study on coal gasification for the production of syngas

Chemical Papers ◽

10.2478/s11696-012-0164-0 ◽

2012 ◽

Vol 66 (7) ◽

Cited By ~ 4

Author(s):

Afsin Gungor ◽

Murat Ozbayoglu ◽

Cosku Kasnakoglu ◽

Atilla Biyikoglu ◽

Bekir Uysal

Keyword(s):

Parametric Study ◽

Coal Gasification ◽

Steam Gasification ◽

Heating Value ◽

Fuel Ratio ◽

Gasification Process ◽

Cold Gas Efficiency ◽

Reactor Temperature ◽

Gas Efficiency ◽

Optimum Working

AbstractIn this parametric study, the effects of coal and oxidiser type, air-to-fuel ratio, steam-to-fuel ratio, reactor temperature, and pressure on H2 and CO amounts at the gasifier output, H2/CO, and higher heating value of the syngas produced have been calculated using a coal gasification model. Model simulations have been performed to identify the optimum values which are assumed to be 100 % for both cold gas efficiency and carbon conversion efficiency in the gasification process. From this study, it may be observed that the moisture content of the coal type is of crucial importance for the air gasification process; the O2 content of similar coals (taking into consideration the moisture and H2 content) is of significant importance for the air gasification process. When compared with air gasification, air-steam gasification becomes a more effective coal gasification method. The optimum working condition for air-steam gasification is to carry out the process at one atmosphere. High gasifier temperatures are not needed for the air-steam gasification of coal.

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Quality assessment of gas produced from different types of biomass pellets in gasification process

Energy Exploration & Exploitation ◽

10.1177/0144598719875272 ◽

2019 ◽

Vol 38 (2) ◽

pp. 406-416 ◽

Cited By ~ 2

Author(s):

Marcel Mikeska ◽

Jan Najser ◽

Václav Peer ◽

Jaroslav Frantík ◽

Jan Kielar

Keyword(s):

Gas Turbines ◽

Combustion Engine ◽

Calorific Value ◽

Internal Combustion ◽

Combustion Gas ◽

Gas Cleaning ◽

Gasification Process ◽

Different Types ◽

Before And After ◽

Cleaning Technology

Gas from the gasification of pellets made from renewable sources of energy or from lower-quality fuels often contains a number of pollutants. This may cause technical difficulties during the gas use in internal combustion gas engines used for energy and heat cogeneration. Therefore, an adequate system of gas cleaning must be selected. In line with such requirements, this paper focuses on the characterization and comparison of gases produced from different types of biomass during gasification. The biomass tested was wood, straw, and hay pellets. The paper gives a detailed description and evaluation of the measurements from a fix-bed gasifier for the properties of the produced gases, raw fuels, tar composition, and its particle content before and after the cleaning process. The results of elemental composition, net calorific value, moisture, and ash content show that the cleaned gases are suitable for internal combustion engine-based cogeneration systems, but unsuitable for gas turbines, where a different cleaning technology would be needed.

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Hydrogen production via integrated configuration of steam gasification process of biomass and water‐gas shift reaction: Process simulation and optimization

International Journal of Energy Research ◽

10.1002/er.7087 ◽

2021 ◽

Author(s):

Mokhtar Akhond Babatabar ◽

Majid Saidi

Keyword(s):

Hydrogen Production ◽

Process Simulation ◽

Steam Gasification ◽

Water Gas Shift ◽

Water Gas Shift Reaction ◽

Simulation And Optimization ◽

Gasification Process ◽

Process Simulation And Optimization ◽

Shift Reaction ◽

Water Gas

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Experimental Investigation of a Packed-Bed Solar Reactor for the Steam-Gasification of Biomass Charcoal

ASME 2008 2nd International Conference on Energy Sustainability, Volume 2 ◽

10.1115/es2008-54118 ◽

2008 ◽

Cited By ~ 1

Author(s):

Nicolas Piatkowski ◽

Christian Wieckert ◽

Aldo Steinfeld

Keyword(s):

Calorific Value ◽

Packed Bed ◽

Energy Conversion Efficiency ◽

Steam Gasification ◽

Solar Simulator ◽

High Quality ◽

Syngas Production ◽

Solar Reactor ◽

Graphite Plate ◽

Concentrated Solar Energy

Gasification of coal, biomass, and other carbonaceous materials for high-quality syngas production is considered using concentrated solar energy as the source of high-temperature process heat. The solar reactor consists of two cavities separated by a SiC-coated graphite plate, with the upper one serving as the radiative absorber and the lower one containing the reacting packed bed that shrinks as the reaction progresses. A 5-kW prototype reactor with an 8 cm-depth, 14.3 cm-diameter cylindrical bed was fabricated and tested in the High-Flux Solar Simulator at PSI, subjected to solar flux concentrations up to 2300 suns. Beech charcoal was used as a model feedstock and converted into high-quality syngas (predominantly H2 and CO) with packed-bed temperatures up to 1500 K, an upgrade factor of the calorific value of 1.33, and an energy conversion efficiency of 29%. Pyrolysis was evident through the evolution of higher gaseous hydrocarbons during heating of the packed bed. The engineering design, fabrication, and testing of the solar reactor are described.

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Hydrogen rich product gas from air-steam gasification of Indian biomasses with waste engine oil as binder

10.21203/rs.3.rs-794017/v1 ◽

2021 ◽

Author(s):

Prashant Sharma ◽

Bhupendra Gupta ◽

Mukesh Pandey

Keyword(s):

Equivalence Ratio ◽

Calorific Value ◽

Steam Gasification ◽

Engine Oil ◽

Small Scale ◽

Hydrogen Yield ◽

Syngas Production ◽

Waste Engine Oil ◽

Product Gas ◽

Biomass Ratio

Abstract Present study concerns with the production of H2 rich product gas by thermochemical energy conversion having biomass gasification as a route for the four biomasses i.e., Kasai Saw Dust, Lemon Grass, Wheat Straw and Pigeon Pea Seed Coat. The biomasses are from the family of woody biomass, grasses, agricultural waste and food process industry wastes. Waste engine oil as an additive is used, which also acts as a binder. Air gasification and Air-steam gasification is applied and compared for product gas composition, hydrogen yield and other performance parameters like lower heating value, energy yield. Product gas constituents, hydrogen production is examined with different steam to biomass ratio (S/B ratio) and equivalence ratio. The equivalence ratio varies from 0.20–0.40 and the steam to biomass ratio varies between 0–4. The waster engine oil is mixed with the biomasses with different percentage of 5 and 10 wt%. For enhancement of feedstock quality palletization process is applied. The H2 yield is greatly affected by the equivalence ratio. Results show maximum H2 production and higher calorific value of product gas at an air to fuel of 0.26 for all the biomass pallets. Also, the S/B ratio observed as important aspect for hydrogen enrichment. Hydrogen yield is maximum at 2.4 steam to biomass ratio. This study considers the rarely studied Indian biomasses with waste engine oil as an additive for hydrogen-rich product gas production and will be beneficial for small scale hydrogen-rich syngas production considering the central Indian region originated biomasses. Statement of Novelty (SON): Research work belongs to eco-friendly use of rarely studied Indian biomass pallets. Equivalence air to fuel ratio (E/R ratio), steam to biomass ratio (S/B ratio) and waste engine oil as additive have been considered to upgrade H2 content and Calorific Value (CV) of the product gas. Novelty of work include use of waste engine oil as additive to make biomass pallets.

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CFD researched on rice husk gasification in a pilot fixed bed up-draft system

Science and Technology Development Journal ◽

10.32508/stdj.v19i3.571 ◽

2016 ◽

Vol 19 (3) ◽

pp. 96-109

Author(s):

Phung Thi Kim Le ◽

Viet Tan Tran ◽

Thien Luu Minh Nguyen ◽

Viet Vuong Pham ◽

Truc Thanh Nguyen ◽

...

Keyword(s):

Mathematical Modeling ◽

Rice Husk ◽

Alternative Energy ◽

Fossil Fuels ◽

Fixed Bed ◽

Steam Gasification ◽

Actual Process ◽

Ansys Fluent ◽

Alternative Energy Sources ◽

Gasification Process

Finding alternative energy sources for fossil fuels was a global matter of concern, especially in developing countries. Rice husk, an abundant biomass in Viet Nam, was used to partially replace fossil fuels by gasification process. The study was conducted on the pilot plant fixed bed up-draft gasifier with two kind of gasification agents, pure air and air-steam mixture. Mathematical modeling and computer simulations were also used to describe and optimize the gasification processes. Mathematical modeling was based on Computational Fluid Dynamics method and simulation was carried by using Ansys Fluent software. Changes in outlet composition of syngas components (CO, CO2, CH4, H2O, H2) and temperature of process, in relation with ratio of steam in gasification agents, were presented. Obtained results indicated concentration of CH4, H2 in outlet was increased significantly when using air-steam gasification agents than pure air. The discrepancies among the gasification agents were determined to improve the actual process.

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Comparison of a block-flow reactor and thermogravimetric analysis in the steam gasification of different types of carbon

Carbon ◽

10.1016/0008-6223(81)90078-6 ◽

1981 ◽

Vol 19 (4) ◽

pp. 309-320 ◽

Cited By ~ 8

Author(s):

Teus Wigmans ◽

Fons van Dam ◽

Jacob A. Moulijn

Keyword(s):

Thermogravimetric Analysis ◽

Flow Reactor ◽

Steam Gasification ◽

Different Types

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THE KINETICS OF CaO ASSISTED PATTUKKU CHARCOAL STEAM GASIFICATION

REAKTOR ◽

10.14710/reaktor.18.1.16-21 ◽

2018 ◽

Vol 18 (1) ◽

pp. 16

Author(s):

Takdir Syarif ◽

H Sulistyo ◽

Wahyudi B Sediawan ◽

B Budhijanto

Keyword(s):

Activation Energy ◽

Tubular Reactor ◽

Steam Gasification ◽

Effect Of Temperature ◽

Composition Analysis ◽

Zone Model ◽

Kinetics Parameters ◽

Exponential Factor ◽

Surface Diffusivity ◽

Gasification Process

Abstract Coal is a solid fuel that can be converted into syngas through gasification process. To obtain optimum gasification process design and operation, in-depth understanding of the influential parameters is required. This study aims to investigate the effect of temperature on the gasification process and to obtain its kinetics parameters. The study was carried out in a tubular reactor equipped with a heater and a condenser. Steam was used as gasifying agent, while CaO was employed as a CO2 adsorbent. The charcoal from coal was subjected to gasification at temperatures of 600°C, 700°C, and 800°C. The ratio of charcoal and CaO was 1:1. The gasification process lasted for 60 minutes with gas sample was taken every 15 minutes for composition analysis. The results showed that a temperature increase of 100°C caused a proportional increase of conversion of about 75% higher. The value of activation energy (Ea) and exponential factor (ko) were 46.645kJ/mole and 328.3894/min, respectively. For mass transfer parameters, values of activation energy for surface diffusion (Es) and surface diffusivity factor (as) were 81.126 kJ/mole and 0.138/min, respectively. Keywords: gasification; mathematical model; Pattukku coal char; steam; Thin Reaction Zone Model

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The Physical and Chemical Properties of Fine Carbon Particles-Pinewood Resin Blends and Their Possible Utilization

Journal of Chemistry ◽

10.1155/2015/137580 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Aviwe Melapi ◽

Sampson N. Mamphweli ◽

David M. Katwire ◽

Edson L. Meyer

Keyword(s):

Fossil Fuels ◽

Turbine Blades ◽

Chemical Properties ◽

Calorific Value ◽

Specific Reference ◽

Wind Turbine Blades ◽

Carbon Particles ◽

Gasification Process ◽

Fine Carbon ◽

By Products

The application of biomass gasification technology is very important in the sense that it helps to relieve the dwindling supply of natural gas from fossil fuels, and the desired product of its gasification process is syngas. This syngas is a mixture of CO and H2; however, by-products such as char, tar, soot, ash, and condensates are also produced. This study, therefore, investigated selected by-products recovered from the gasification process of pinewood chips with specific reference to their potential application in other areas when used as blends. Three samples of the gasification by-products were obtained from a downdraft biomass gasifier system and were characterized in terms of chemical and physical properties. FTIR analysis confirmed similar spectra in all char-resin blends. For fine carbon particles- (soot-) resin blends, almost the same functional groups as observed in char-resin blends appeared. In bomb calorimeter measurements, 70% resin/30% char blends gave highest calorific value, followed by 50% resin/50% soot blends with values of 35.23 MJ/kg and 34.75 MJ/kg consecutively. Provided these by-products meet certain criteria, they could be used in other areas such as varnishes, water purification, and wind turbine blades.

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