Search results for "Wood gas generator"

Gasification of pelletized renewable fuel for clean energy production

2011

Abstract The main aim of the study was to develop and investigate a small-scale experimental gasification technique for the effective thermal decomposition of pelletized renewable fuels (wood sawdust, wheat straw). The technical solution of the biomass gasifier for gasification of renewable fuels presents a downdraft gasifier with controllable additional heat energy supply to the biomass using the radial propane flame injection into the bottom part of the biomass layer. From the kinetic study of the mass conversion rate of pelletized biomass and variations of the composition of produced gas it is concluded that the process of biomass gasification is strongly influenced by the amount of addi…

Development of net energy ratio and emission factor for quad-generation pathways

2014

Published version of an article in the journal: Energy Systems. Also available from the publisher at: http://dx.doi.org/10.1007/s12667-014-0126-4 The conversion of biomass to four different outputs via gasification is a renewable technology that could reduce the use of fossil fuels and greenhouse gas (GHG) emissions. This study investigates the energy aspects for a new concept of biomass based quad-generation plant producing power, heat, methanol and methane. Circulating fluidized bed gasifier and the gas technology institute (GTI) gasifier technologies are used for this quad-generation process. Two different biomass feedstocks are considered in this study. The net energy ratio for six diff…

Future district heating plant integrated with municipal solid waste (MSW) gasification for hydrogen production

2019

Abstract Characterizing municipal solid waste (MSW) is a critical step in planning, designing, operating, or upgrading solid waste management systems. For a theoretical investigation of hydrogen production by gasification and water-gas shift reaction, we characterized Norwegian MSW and used the data. Three different gasification setups, named as ‘A-1’, ‘A&S-2’, and ‘S-3’ were modeled using Aspen plus simulation software for direct and indirect gasification processes according to the different gasification agents. The MSW characterization result showed a reasonable agreement with existing studies in different countries. The maximum hydrogen yield achieved in setup ‘S-3’ was around 94% of the…

Sulphate Removal from Water by Carbon Residue from Biomass Gasification: Effect of Chemical Modification Methods on Sulphate Removal Efficiency

2016

Sulphate removal from mine water is a problem because traditional chemical precipitation does not remove all sulphates. In addition, it creates lime sediment as a secondary waste. Therefore, an inexpensive and environmental-friendly sulphate removal method is needed in addition to precipitation. In this study, carbon residues from a wood gasification process were repurposed as precursors to a suitable sorbent for SO42- ion removal. The raw material was modified using ZnCl2, BaCl2, CaCl2, FeCl3, or FeCl2. Carbon residues modified with FeCl3 were selected for further consideration because the removal efficiency toward sulphate was the highest. Batch sorption experiments were performed to eval…

Numerical investigation of slag formation in an entrained-flow gasifier

2018

Modeling of the catalytic effects of potassium and calcium on spruce wood gasification in CO2

2016

Abstract Using previously reported thermogravimetric analysis measurements, the effects of calcium and potassium on the char gasification rate of spruce wood were modeled. Spruce wood was leached of inorganic ash elements and doped with measured amounts of potassium and calcium. The wood was gasified in an isothermal thermogravimetric analysis device in CO 2 where the devolatilization of the wood, char formation and char gasification all occurred inside the preheated reactor. A new method for separating the effects of devolatilization and char gasification is presented. Kinetic models were evaluated for their ability to describe the observed catalytic effects of potassium and calcium on the…

Overview and Essentials of Biomass Gasification Technologies and Their Catalytic Cleaning Methods

2016

Obtaining a tar-free biosyngas from biomass gasification processes has been the subject of many studies in the past 2 decades, and it still remains the major technologic and economic challenge. Unfortunately, the countless publications about gasification technologies and different techniques permitting reduction of the tar present at the outlet of gasifier reactors usually confuse inexperienced persons who attempt to further research this subject. More than presenting the basis of biomass gasification technologies and positioning them among other bioenergies, this work mainly aims at reviewing and comparing the different methods developed in order to produce a tar-free biosyngas. In this wa…

Numerical Investigation of a Wood-Chip Downdraft Gasifier

2019

Biomass gasification is regarded as one of the most promising technology in the renewable energy field. The outcome of such operation, i.e. the synfuel, can be exploited in several ways, for example powering engines and turbines, and is considered more flexible than the biomass itself. For this reason, a careful analysis of the gasification performance is of paramount importance for the optimization of the process. One of the techniques that can be used for such a purpose, is the numerical analysis. CFD is indeed a tool that can be of great help in the design and study of the operation of the gasifier, allowing for an accurate prediction of the operating parameters. In this work, a downdraf…

Modeling biomass char gasification kinetics for improving prediction of carbon conversion in a fluidized bed gasifier

2014

Gasification of biomass in a fluidized bed (FB) was modeled based on kinetic data obtained from previously conducted thermo- gravimetic analysis. The thermogravimetric analysis experiments were designed to closely resemble conditions in a real FB gasifier by using high sample heating rates, in situ devolatilization and gas atmospheres of H 2 O / H 2 and CO 2 / CO mixtures. Several char kinetic models were evaluated based on their ability to predict char conversion based on the thermogravimetric data. A modified version of the random pore model was shown to provide good fitting of the char reactivity and suitability for use in a reactor model. An updated FB reactor model which incorporates t…