Beech Leaves Briquettes as Fuel for a Home Combustion Unit

Abstract

This study is aimed at the possibility of the fallen (waste) beech leaves usage as material for briquettes production. The main purpose of beech leaves briquetting in this study is the possibility of using it in small home combustion units, as partial substitute of wood. From the briquetting point of view, it is necessary to dry the leaves to approximately 15% of water content (it takes more than a month by free (natural) drying in an approximately 10 cm high layer inside a heated room). Beech leaves briquetting by automatic press is an easy process, but with diverse lengths of briquettes at the output (2-20 cm). Proximate and ultimate analyses of collected beech leaves were done. A briquette sample was subjected to thermogravimetric analysis, which shows the temperature ranges of drying and hemicellulose, cellulose and lignin decomposition. The determined temperature ranges correspond to those from other literature sources. Combustion tests proved the possibility of beech leaves briquettes usage as fuel in a small combustion unit. All limit values of the actual European standard EN 13240:2001 were met and some limit values of future European Standard Commission regulation (EU) 2015/1185 were met as well. Results of energy efficiency and mass concentrations of pollutants in the flue gas will differ with different stove and different stove settings. Due to the properties of the beech leaves briquettes (high mass fraction of ash and fast disintegration on the grate during the combustion process), it is appropriate, especially for long term use, to combine this kind of fuel with a conventional one.

Beech leaves briquettes’ and standard briquettes’ combustion: comparison of flue gas composition

“…The combustion tests demonstrated the possibility of meeting actual legislative limits, but the Commission regulation (EU) 2015/1185 [22] is much stricter; therefore, the described combustion equipment was not able to meet those limits with beech leaves briquettes, used as a fuel. This article expands on the earlier research by Ryšavý et al [21].…”

“…Possibilities of beech leaves briquettes usage as the stove fuel for household heating was observed by previous research of Ryšavý et al [21]. In this work, beech leaves were collected, spontaneously dried, crushed and pressed into briquettes.…”

“…For the combustion tests, two fuels were chosen. The first one was the beech leaves briquettes, which have been described in detail by Ryšavý et al [21]. The second used fuel was standard wooden briquettes (with ÖNORM certification) made only from pure dry spruce shavings (bark and additional binders free).…”

Co-Gasification of Pistachio Shells with Wood Pellets in a Semi-Industrial Hybrid Cross/Updraft Reactor for Producer Gas and Biochar Production

“…The granulometry of the pistachio shells after the standard shelling process is very homogenous, and it could be mixed and directly used in appliances designed for pellets, as shown by Ryšavý et al [29], which is important due to the energy required for the densification of biomass [30][31][32]. In the study of Hu et al [33], pistachio shells were gasified under specific laboratory conditions, while the KOH-activated char was described in detail and tested for its capacitive performance in aqueous electrolytes in electric doublelayer capacitors.…”

Evaluation and Safety Assessment of Biomass-/Waste-Generated Producer Gas

“…For example, several studies that specify biomass-based waste utilization in small combustion applications for household heating were published. Unfortunately, these applications have very limited scope of use and do not solve the overall problem [4], [5]. Moreover, alternative ways of utilisation of this material are, to some extent, ignored.…”