Wood Biomass Gasification Research Articles

Life Cycle Assessment of a Wood Biomass Gasification Plant and Implications for Syngas and Biochar Utilization

The growing attention regarding the environmental challenges in the energy sectors pushes the industrial system toward the investigation of more sustainable and renewable energy sources to replace fossil ones. Among the promising alternatives, biomass is considered a valid source to convert the system and to reduce the fossil fraction of the national energy mixes, but its multiple potential uses need an environmental evaluation to understand the actual benefit when it is used as an energy resource. For this purpose, life cycle assessment (LCA) is applied to a wood biomass gasification system aimed to produce electricity and heat generated after the combustion of the produced syngas and the management of the biochar. The aim is to provide a quantitative comparison of (i) a baseline scenario where wood biomass is sourced from waste and (ii) a second scenario where wood biomass is drawn from dedicated cultivation. A further evaluation was finally applied to investigate the environmental implications associated with the biochar composition, assuming it was used on land. The proposed strategies resulted in an environmental credit for both the examined scenarios, but the outcomes showed a net preference for the baseline scenario, resulting in better environmental performances for all the examined categories with respect to the second one. It underlines the potentialities of using waste-sourced biomass. However, according to the Climate Change category, if on-site dedicated biomass cultivation is assumed for the second scenario, the baseline is considered preferable only if the biomass transportation distance is <600 km, which is estimated as a theoretical distance for scenarios to break even. Finally, biochar composition proved a particular concern for toxicity-related categories. This study highlights the importance of applying objective and standardized methodologies such as LCA to evaluate energy production systems based on alternative sources and to support decision-making toward achieving sustainability goals.

Energy and Exergy Analyses of a Sustainable Calcination Process in a Vertical Limekiln Performing with Producer Gas as Renewable Biofuel Derived from Eucalyptus Wood Biomass Gasification

Energy and Exergy Analyses of a Sustainable Calcination Process in a Vertical Limekiln Performing with Producer Gas as Renewable Biofuel Derived from Eucalyptus Wood Biomass Gasification

Thermogravimetric and thermovolumetric study of municipal solid waste (MSW) and wood biomass for hydrogen-rich gas production: a case study of Tashkent region.

Application of municipal solid and wood waste, as dominant sources of biomass, could be a promising alternative for producing energy from renewables via thermochemical gasification technology. In this paper, a study of thermogravimetric analysis (TGA) and excurrent gas composition produced by the municipal solid waste (MSW) and wood biomass gasification is presented. Thermogravimetric and heat flow curves for waste samples were performed at the temperature interval of 20-890 °C with a heating rate of 10 °C min-1 under a nitrogen atmosphere. According to thermal analysis data, differential scanning calorimetry (DSC) curves, the degradation stages of waste samples was determined, which correspond to the mono- or bimodal evolution of volatile compounds and the degradation of the resulting carbon residue. The gasification experiments were conducted in a high-pressure quartz reactor at temperatures of 850, 900, and 950 °C, using steam (0.3 g/min) and argon (2 dm3/min) as the gasifying agents. To ascertain the syngas composition, gas chromatography was employed in conjunction with a thermal conductivity detector. Both types of biomass showed remarkably similar syngas compositions. The highest concentration of hydrogen-rich gases was recorded at 950 °C for wood biomass, with 42.9 vol% and 25.2 vol% for hydrogen (H2) and carbon monoxide (CO), and for MSW, with an average 44.2 vol% and 18 vol% for H2 and CO. Higher temperatures improved the syngas composition by promoting endothermic gasification reactions, increasing hydrogen yield while decreasing tar and solid yields. This research helped to comprehend the evolution of the gasification process and the relationship between increased H2 and CO production as the gasification temperature increased.

3D printing of ordinary Portland cement with waste wood derived biochar obtained from gasification

This research aims to use a circular economy approach for the incorporation of biochar powder from wood biomass gasification (at 0, 5, 10, 15 and 20 wt%) in combination with ordinary portland cement and additive manufacturing (3D printing), specifically using direct ink writing technique. This technique can be used both at large scale and low cost. The importance of this investigation lies in the incorporation of a worldwide large scale waste, biochar, into 3D printing, which could opens up sustainable options for fabrication. A number of four formulations were developed, wherefrom only one was suitable for the 3D printing process, which was attributed to the formulation stability in preserving the shape, and to the surface finishing of the printed pieces as well. For compression tests, cylindrical samples were printed and further evaluated to analyze the process and the waste effect on strength. Additional shapes were built with the same technology to evaluate the limitations of the method. The microstructure of all these formulations has been evaluated using X-ray diffraction and scanning electron microscopy, founding that only the formulation with 10 wt% of biochart was feasible to be made with the direct ink writing technique. Weibull statistics was also included to analyze the variablility of the compression results.

TECHNICAL AND ECONOMIC ANALYSIS OF PRODUCING 250 KW POWER USING THE GASIFICATION SYSTEM AT THE VARIETY WOODS AND GREENHEART LIMITED SAWMILL IN GUYANA.

A technical and economic analysis was conducted on the viability of operating a 250 kW wood biomass gasification power plant to produce electricity for the sawmill at Variety Woods and Greenheart Ltd. in Guyana. The major economic cost factors considered in the gasification plant’s 20-year life comprised a wood chipper, pellet machine, gasification system and operation and maintenance cost. The researchers did a cash flow projection using a spreadsheet program to determine the net present value (NPV), internal rate of return (IRR), the payback period and the return on investment (ROI). The main cash inflow in the analysis is savings from diesel fuel import to power the current diesel power plant at the sawmill. The implementation of the wood biomass gasification plant will save the company US$ 99,600 annually. In the economic analysis, a sensitivity analysis was conducted by the researchers on the capital cost, which was the major factor affecting the economic assessment. In both scenarios, the economic analysis of the proposed gasification plant shows a positive NPV, which suggests an attractive investment financially. The IRR for case one was found to be 4.70% and for case 2 was 6%. For case 1, the gasification plant's return on investment is 13.3% and for case 2, it is 36.56%. The payback period for the wood biomass gasification system was 20 years 5 months for case 1 and for case 2 was observed to be 10 years 1 month.

Solubility of Tar Model Compounds in Various Solvents for Tar Removal in a Dual Fluidized Bed Biomass Gasification Process

Production of high quality product gas via biomass steam gasification is a promising technology. However, impurities in the product gas, namely tars, cause problems in the downstream gas processing operations and thus they need to be removed efficiently. Oil scrubbing is an effective solution for tar removal due to its non-polar characteristic which is similar to tar nature. In this research, solubility values of five simulated tar compounds were experimentally investigated for selecting the new scrubbing solvent. The simulated tar compounds investigated represent those found in the dual fluidized bed steam gasification of wood biomass, which are: naphthalene, biphenyl, anthracene, fluoranthene, and pyrene. The scrubbing solvents tested in this research are classified into biodiesels, vegetable oils, and diesel. Biodiesel used are rapeseed methyl ester (RME) and 2 different palm methyl esters (denoted as PME1 and PME2). Vegetable oils are sunflower oil, refined palm oil, Thai rice bran oil, and crude palm oil. All of the solubility tests were performed in the laboratory-scale test-rig at 30, 50, 70, and 80°C. Biodiesels are found to be the effective solvent in dissolving the tar compounds. PME1 shows the similar tar removal performance to RME but is more readily available; therefore, PME1 is chosen to be used as a scrubbing solvent at the Thailand 1 MWel prototype DFB gasifier at Nong Bua district in Nakhon Sawan province, Thailand.

Thermodynamic and Experimental Investigation of Solar-Driven Biomass Pyro-Gasification Using H2O, CO2, or ZnO Oxidants for Clean Syngas and Metallurgical Zn Production

The solar gasification of biomass represents a promising avenue in which both renewable solar and biomass energy can be utilized in a single process to produce synthesis gas. The type of oxidant plays a key role in solar-driven biomass gasification performance. In this study, solar gasification of beech wood biomass with different oxidants was thermodynamically and experimentally investigated in a 1.5 kWth continuously-fed consuming bed solar reactor at 1200 °C under atmospheric pressure. Gaseous (H2O and CO2) as well as solid (ZnO) oxidants in pellet and particle shapes were utilized for gasifying beech wood, and the results were compared with pyrolysis (no oxidant). As a result, thermodynamic predictions provided insights into chemical gasification reactions against oxidants, which can support experimental results. Compared to pyrolysis, using oxidants significantly promoted syngas yield and energy upgrade factor. The highest total syngas yield (63.8 mmol/gbiomass) was obtained from biomass gasification with H2O, followed by CO2, ZnO/biomass mixture (pellets and particles), and pyrolysis. An energy upgrade factor (U) exceeding one was achieved whatever the oxidants, with the maximum U value of 1.09 from biomass gasification with ZnO, thus highlighting successful solar energy storage into chemical products. ZnO/biomass pellets exhibited greater gas yield, particularly CO, thanks to enhanced solid–solid reaction. Solid product characterization revealed that ZnO can be reduced to high-purity Zn through solar gasification, indicating that solar-driven biomass gasification with ZnO is a promising innovative process for CO2-free sustainable co-production of metallic Zn and high-quality syngas.

Performance analysis of power generation by wood and woody biomass gasification in a downdraft gasifier

An equilibrium simulation model was developed by applying Aspen Plus to evaluate the performance of 28 wood and woody biomass (W&WB) gasification in a downdraft gasifier integrated with power production unit. The developed simulation model does not focus the gasification process as a closed box, it considers important processes in gasification like drying, pyrolysis, combustion, gasification and integrated with power production plant (combustion chamber plus gas turbine). The results for the 28 W&WB alternatives show that the net power produced from 1-ton feedstock entering to the gasification system is between the interval [0-400 kW/ton] and among them, gasification system derived from Tamarack bark biomass significantly outranks all other systems by producing 363 kW/ton, owing to the favorable results obtained in the performance analysis. Moreover, effect of various operating parameters such as gasification temperature and air to fuel ratio (AFR) on the system performance was carried out. Finally, the developed model is applied as an effective tool to assess the impact of so many biomasses and operating parameters on output power.

Mogućnosti korišćenja otpadne drvne i poljoprivredne biomase u Srbiji u kogeneracionim postrojenjima

Wood and agricultural remains, such as raw materials can be used for heating (30% cheaper than gas from gas pipeline, 50% of electricity or heating oil), for electricity production and for other needs. In this paper, modern integrated solutions for the application of biomass and cogeneration will be presented. With such solutions, synthetic gas with certain content of methane is obtained in the gasification area, and then purified and used in a CHP (Combined Heat and Power) e.g., internal combustion engine. The gasification of waste wood and agricultural biomass for heat and / or electricity in the CHP plant preserves and saves optimally available resources. Gas obtained by gasification in the cogeneration plant is used in the gas engine that has an asynchronous generator for electricity production on its shaft. As for waste wood and agricultural biomass, they are very little used in energy in Serbia for energy purposes. The main reason for the non-use of waste and agricultural biomass for energy purposes in some production existences is due to the underdeveloped supply chains in the form of fuels that is suitable for use for energy purposes of these manufacturers. For the rational use of these resources, it is necessary to perform a study for defined energetic territories, which, among other things, should contain data for types and available quantities, formation of origin and energy potentials.

Effects of the hydrogen and methane fractions in biosyngas on the stability of a small reciprocated internal combustion engine

A bio-syngas, produced from wood biomass gasification, is used with a small reciprocated spark ignition engine for higher thermal efficiency. In this experiment, as the knocking doesn’t occur even though the ignition timing is 70 deg-BTDC (before top dead center), the MBT, most-advanced for best torque ignition timing, couldn’t be determined. This phenomena, without knocking combustion, are reported by several researchers. In this report, the way to determine the ignition timing for the maximum efficiency is shown. With the cylinder pressure measurement, when the maximum heat release rate position is set near TDC, top dead center, the thermal efficiency shows the maximum and the stability shows the best in any hydrogen fraction or any methane fraction of the mixed fuel.Po.

Use of gasifier-based electric power stations for improving the economy of autonomous power supply systems in Russia

In Russia, significant amounts of waste of logging and woodworking that can be used for energy production are generated. In this paper, we consider an autonomous power supply system, including a wood biomass gasification power plant (BGPP), a diesel power plant (DPP), one or several wind turbines (WT), and electricity consumers with their load schedule. The mathematical formulation of the problem of optimizing the structure and modes of operation of the power supply system is reduced to minimizing the objective function with a number of additional constrains. The objective function is equal to total discounted costs for the construction and operation of the system or the cost of electricity produced. Additional constrains are balances for power, primary, secondary and final energy. The power supply system was modeled for different values of diesel and wood fuels prices, average long-term wind speed, technical and economic indicators of power plants. According to the results of calculations, the zones of technologies efficiency and the cost of electricity produced are determined. It is shown that biomass gasification power plants with gas storage tanks are much more economical than diesel power plants and can displace them at current diesel fuel prices. In areas with high average annual wind speeds, biomass gasification power plants should be used in conjunction with wind turbines.

Upgrading Wood Gas Using Bentonite Clay: A Multiscale Modeling and Simulation Study.

Wood gas is the producer gas resulting from gasification of wood biomass and is an important renewable fuel gas in rural areas. This study assessed the capacity of bentonite, a widely used clay mineral, to upgrade wood gas via pressure swing adsorption in order to improve its calorific value (i.e., the amount of energy released per kilogram of gas). Grand canonical Monte Carlo molecular simulations using a self-consistent force field were performed to generate adsorption isotherms for wood gas components—methane, carbon monoxide, carbon dioxide, hydrogen, nitrogen, and oxygen—in montmorillonite (the main crystalline constituent of bentonite) at conditions appropriate to downdraft gasification. The Langmuir adsorption isotherm model was successfully fitted to each component’s adsorption isotherm and was then coupled with a batch equilibrium approach to model a single-stage pressure swing adsorption system with a discharge stream at ambient pressure. A response surface was then computed in terms of the net change in the calorific value as a function of both adsorbent quantity and operating pressure. It was found that the system can improve the calorific value of the gas by over five percent.

Simulation and Optimization of Wood Biomass Gasification Regimes in a Flow of Steam-Oxygen Blast

Plant biomass (such as wood, agricultural and logging waste) is considered a raw material with better environmental characteristics than fossil fuels. The main prospects for bioenergy are associated with combustion and gasification in small power systems, including as part of hybrid power plants. To increase the efficiency of gasification processes, an oxygen-enriched gasifying agent is often used, as well as fine grinded fuel (to intensify transport processes and chemical transformations). Thermodynamic estimates show the possibility of achieving the efficiency of the gasification at the level of 0.8–0.9, however, the experimentally achieved values rarely exceed 0.7. In this work, using mathematical modeling, we investigated the possibility of increasing the efficiency of the biomass gasification.

Numerical simulation of reactive gas-particle flow in a solar jet spouted bed reactor for continuous biomass gasification

Solar steam gasification of beech wood biomass in a novel solar conical jet spouted bed reactor was studied. A 3D numerical model of the reactive two-phase gas-particle flow was developed and the model was experimentally validated. The cavity-type solar reactor was operated in both direct and indirect heating configurations at a constant wall temperature of 1200 °C with a biomass feeding rate that varied from 1.2 g/min to 2 g/min. Experiments showed that directly heating the particles increases the H2 yield and the carbon conversion efficiency. The Computational Fluid Dynamics (CFD) model was developed to thoroughly investigate the biomass conversion process inside the conical jet spouted bed subjected to direct or indirect solar irradiations. The desired vigorous cyclic flow pattern of the biomass particles was accurately predicted by the model with peak particles velocity of 2 m/s in the spout region. The maximum temperature reached by the indirectly-irradiated particles is about 1200 °C while it is above 1500 °C when considering directly-irradiated particles. Direct heating thus increases both particles gasification rates and carbon conversion efficiency. Furthermore, simulations reveal that the reaction zone temperature is 100 °C higher for the direct heating configuration. This promotes the H2 formation at the expense of CH4. The steam oxidant concentration, gas products distribution and particles trajectories inside the cavity were also investigated to identify improvement strategies for enhancing the phase mixing and the gas/solid residence time.

The modern state of wood biomass gasification technologies and their economic efficiency

Abstract This paper presents an overview of state-of-the-art in single- and multistage wood biomass gasification technologies and assesses their economic efficiency. We compare the cost of electricity generated through the use of different types of fuel (gas, diesel, coal, wood chips and wood pellets) and show that the most promising technology for processing biomass is multi-stage gasification.

Gasification of wood biomass with renewable hydrogen for the production of synthetic natural gas

In this article we argue that the broad diffusion of renewables such as solar and wind power in the global energy system will probably require the development of efficient systems for the storage of excess electricity produced during off-peak hours. We also point out that in many places on Earth wood is a type of biomass that is available in large quantities as by-product of agricultural and industrial activities, which could be valorized through gasification processes that produce syngas. We combine these two observations by presenting an analysis of a power-to-gas system in which hydrogen obtained via electrolysis is used for the hydrogasification of wood. This process produces a synthetic natural gas (SNG) mixture that consists mostly of methane with only minor impurities of hydrogen. We show that the SNG generated in this sustainable way represents an efficient means for renewable energy storage. We also study wood hydrogasification processes with hydrogen production methods alternative to electrolysis, such as the partial oxidation of biomass, the water gas shift reaction, and the Sabatier reaction. We determine the process operating conditions that maximize the SNG yield and energy efficiency. Through an economic assessment we examine the applicability of the process to a plant located in Northern Italy. In all process types SNG exhibits characteristics that comply with methane grid quality requirements. We conclude that SNG production through wood hydrogasification can compete with methane market prices when using zero-cost renewable electricity produced during off-peak hours.

A Review of Technologies for Multistage Wood Biomass Gasification

Currently, small-scale distributed power generation is being intensively developed in Russia and abroad. Given the rise in the rates for the electric and thermal energy, the development of new territories, and the technical infeasible connection to the power supply system, one of the most promising variants of supplying isolated consumers with power is the application of wood biomass gasification technologies. Analysis of the studies in this sphere shows that considerable attention is paid to enhancing the gasification efficiency and ensuring the purity of the gas. These problems are solved using multistage gasification technology. This technology involves the pyrolysis and gasification in separated zones of the gasifier or individual interconnected reactors, which enables achieving the optimal conditions for the conversion of biomass at every separate stage. The major advantage of multistage gasifiers is the production of synthesis gas with a low content of tar. The article represents a review of technologies for multistage wood biomass gasification and comparison of the relevant gasifiers of various types; the basic single-stage and multistage wood biomass gasification technologies are examined and their technical characteristics and examples of their commercial implementation are provided. Analysis of the current situation shows that predominantly foreign multistage wood biomass gasification technologies/plants have found practical application. These technologies allow the produced syngas to be directly used in internal combustion engines and gas turbines without employing expensive auxiliary detarring plants.

Design, simulation and experimental study of a directly-irradiated solar chemical reactor for hydrogen and syngas production from continuous solar-driven wood biomass gasification

The use of concentrated solar energy as the high-temperature heat source for the thermochemical gasification of biomass is a promising prospect for producing CO2-neutral chemical fuels (syngas). The solar process saves biomass resource because partial combustion of the feedstock is avoided, it increases the energy conversion efficiency because the calorific value of the feedstock is upgraded by the solar power input, and it also reduces the need for downstream gas cleaning and separation because the gas products are not contaminated by combustion by-products. A new concept of solar spouted bed reactor with continuous biomass injection was designed in order to enhance heat transfer in the reactor, to improve the gasification rates and gas yields by providing constant stirring of the particles, and to enable continuous operation. Thermal simulations of the prototype were performed to calculate temperature distributions and validate the reactor design at 1.5 kW scale. The reliable operation of the solar reactor based on this new design was also experimentally demonstrated under real solar irradiation using a parabolic dish concentrator. Wood particles were continuously gasified at temperatures ranging from 1100 °C to 1300 °C using either CO2 or steam as oxidizing agent. Carbon conversion rates over 94% and gas productions over 70 mmol/gbiomass were achieved. The energy contained in the biomass was upgraded thanks to the solar energy input by a factor of up to 1.21.

Experimental analysis of continuous steam gasification of wood biomass for syngas production in a high-temperature particle-fed solar reactor

Solar steam gasification of beech wood biomass has been performed in a novel high-temperature continuously-fed solar reactor for the thermochemical conversion of low-grade carbonaceous feedstock into transportable and storable gaseous fuels (syngas). The 1.5 kWth cavity-type solar reactor was operated in the temperature range of 1100–1300 °C. Large wood biomass particles (3–5 mm size) were continuously fed and gasified with the oxidizing agent to produce syngas, thus demonstrating the reactor suitability for large particle size processing. Operating parameters were varied in order to optimize the syngas production. The effect of steam flow-rate, carrier gas flow-rate, temperature, and biomass feeding rate on the syngas yield and reactor performances was experimentally investigated. The increase of steam flow-rate favored H2, CO2 and CH4 and reduced CO production. A noteworthy increase of the syngas yield with the temperature was highlighted, while the increase of carrier gas flow-rate was detrimental to the amount of syngas produced because of lowered gas residence time. The increase of biomass feeding rate (in the range of 0.8–1.8 g/min) showed noteworthy impact on the syngas composition without affecting the reactor performance, yielding high-quality syngas with a carbon conversion rate above 80%, while the total syngas yield was stable at about 70 mmol/gbiomass.

MODELING OF COMBINED HEAT AND POWER PLANT BASED ON A MULTI-STAGE GASIFIER AND INTERNAL COMBUSTION ENGINES OF VARIOUS POWER OUTPUTS

The paper is concerned with an integrated system of internal combustion engine and mini combined heat and power plant (ICE-CHP). The system is based on multi-stage wood biomass gasification. The use of producer gas in the system affects negatively the internal combustion engine performance and, therefore, reduces the efficiency of the ICE-CHP plant. A mathematical model of an internal combustion engine running on low-calorie producer gas was developed using an overview of Russian and foreign manufacturers of reciprocating units, that was made in the research. A thermal calculation was done for four-stroke gas engines of different rated power outputs (30, 100 and 250 kW), running on producer gas (CO2 – 10.2, CO – 45.8, N2 – 38.8%). Thermal calculation demonstrates that the engine exhaust gas temperature reaches 500 – 600°C at the rated power level and with the lower engine power, the temperature gets higher. For example, for an internal combustion engine power of 1000 kW the temperature of exhaust gases equals 400°C. A comparison of the efficiency of engine operation on natural gas and producer gas shows that with the use of producer gas the power output declines from 300 to 250 kWe. The reduction in the effective efficiency in this case makes up 2%. The measures are proposed to upgrade the internal combustion engine to enable it to run on low-calorie producer gas.