Review of micro- and small-scale technologies to produce electricity and heat from Mediterranean forests׳ wood chips

The thermal decomposition of wood chips from an apple tree is studied in a static air atmosphere under isothermal conditions. Based on the thermogravimetric analysis, the values of the apparent activation energy and pre-exponential factor are 34 ± 3 kJ mol−1 and 391 ± 2 min−1, respectively. These results have also shown that this process can be described by the rate of the first-order chemical reaction. This reaction model is valid only for a temperature range of 250–290 °C, mainly due to the lignin decomposition. The obtained results are used for kinetic prediction, which is compared with the measurement. The results show that the reaction is slower at higher values of degree of conversion, which is caused by the influence of the experimental condition. Nevertheless, the obtained kinetic parameters could be used for the optimization of the combustion process of wood chips in small-scale biomass boilers.

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Environmental assessment of small-scale production of wood chips as a fuel for residential heating boilers

Renewable Energy ◽

10.1016/j.renene.2013.06.041 ◽

2014 ◽

Vol 62 ◽

pp. 106-115 ◽

Cited By ~ 20

Author(s):

Bernat Esteban ◽

Jordi-Roger Riba ◽

Grau Baquero ◽

Rita Puig ◽

Antoni Rius

Keyword(s):

Environmental Assessment ◽

Wood Chips ◽

Small Scale ◽

Scale Production ◽

Residential Heating

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Effect of Ambient Temperature during Small Scale Co-Composting of Human Faecal Matter

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.3316 ◽

2012 ◽

Vol 518-523 ◽

pp. 3316-3320

Author(s):

Xuan Liu ◽

Zi Fu Li ◽

Eric Bosc ◽

Heinz Peter Mang

Keyword(s):

Ambient Temperature ◽

Experimental Results ◽

Wood Chips ◽

Small Scale ◽

Human Faeces ◽

Composting Process ◽

High Efficient ◽

Temperature Ranges ◽

Improvement Measures ◽

Reactor Temperature

To find a suitable and affordable technology for the composting of human faeces in the Ger Areas of Ulaanbaatar, Mongolia, new composting system was developed and several trials have been conducted. Under controlled conditions with pH, temperature and moisture, three different mixtures were tested: human faeces plus sawdust, human faeces plus straw and human faeces plus wood chips. Based on the experimental results it can be concluded that the composting process, if started under controlled and appropriate conditions, could start and last about 32 days. Meanwhile, when ambient temperature drops sharply, the reactor temperature correspondingly drops sharply, but shows different results in the different temperature ranges. For stable and high efficient composting under such condition, further improvement measures and more trials should be done in next stages.

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Modelling of wood chips gasification process in ASPEN Plus with multiple validation approach

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq180709034c ◽

2019 ◽

Vol 25 (3) ◽

pp. 217-228

Author(s):

Ivana Cekovic ◽

Nebojsa Manic ◽

Dragoslava Stojiljkovic ◽

Marta Trninic ◽

Dusan Todorovic ◽

...

Keyword(s):

Experimental Work ◽

Equilibrium Model ◽

Beech Wood ◽

Aspen Plus ◽

Model Verification ◽

Wood Chips ◽

Small Scale ◽

Model Parameters ◽

Producer Gas ◽

Heating Value

A thermochemical equilibrium model is formulated for wood chips downdraft gasification. Steady state ASPEN Plus simulator was utilized to evaluate producer gas composition and low heating value. Three cases are considered, due to mathematical model developed issues, and described in details. Experimental work was carried out within commercial small-scale CHP system where twelve beech wood samples were taken. Equivalence ratio is between 0.32 and 0.38 and air-fuel ratio ranges from 1.49 to 1.81, when gasifier capacity is optimal, at 250 kW. Mole fractions of CO2, H2, CO, CH4 and N2, in dry producer gas, are respectively, 16.06-17.64, 17.98-20.33, 13.71-17.26, 1.65-2.89 and 43.21-48.36. Multiple validation approach was applied for model verification. The results are in reasonable agreement with different literature sources (experimental work and modeling) and in a great agreement with the modified equilibrium model developed in Engineering Equation Solver found in the literature. Result deviations are explained by two major facts: wood downdraft gasification experiments are to a certain extent different and the model parameters could not be adjusted enough to fully minimize differences between model results. Predicted low heating value of dry producer gas is between 4.67-5.61 MJ/Nm3.

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Comparative cost evaluation of heating oil and small-scale wood chips produced from Euro-Mediterranean forests

Renewable Energy ◽

10.1016/j.renene.2014.08.038 ◽

2015 ◽

Vol 74 ◽

pp. 568-575 ◽

Cited By ~ 5

Author(s):

Bernat Esteban ◽

Jordi-Roger Riba ◽

Grau Baquero ◽

Antoni Rius

Keyword(s):

Wood Chips ◽

Cost Evaluation ◽

Small Scale ◽

Mediterranean Forests ◽

Comparative Cost ◽

Heating Oil

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R&D On Micro-Gasifier for Power Generation From Solid Wastes

ASME 2004 Power Conference ◽

10.1115/power2004-52111 ◽

2004 ◽

Cited By ~ 1

Author(s):

Kunio Yoshikawa

Keyword(s):

Power Generation ◽

High Temperature ◽

Waste Treatment ◽

Solid Wastes ◽

Wood Chips ◽

Small Scale ◽

Generation System ◽

Evolved Gas ◽

Power Generation System ◽

Main Components

A small-scale power generation system including a process of producing low-BTU gas by gasification of wastes has been developed. This system is called as the Micro STAR-MEET. Because the size of this system is small, on-site waste treatment is possible. Wastes are continuously fed into the gasifier and, high temperature air and steam are introduced into the gasifier and reformer to gasify and reform wastes. A pilot plant was constructed in order to investigate the performance of the Micro STAR-MEET system, and experiments using wood chips and plastics as fuels were conducted. Sufficient amount of gas that has 4.0 MJ/m3N HHV was evolved so that the dual-fueled diesel engine could be driven. The main components of the evolved gas were CO and H2. In this study, the gas that could be used as a fuel for the engine was evolved constantly, which indicates that the Micro STAR-MEET system is technically feasible.

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