Research on the Kinetics of Pyrolysis of Wood-Based Panels in Terms of Waste Management

Jaworski Jaworski,Kajda-Szcześniak Kajda-Szcześniak

doi:10.3390/en12193705

Jaworski Jaworski, Kajda-Szcześniak Kajda-Szcześniak

Open Access

https://doi.org/10.3390/en12193705

Copy DOI

Journal: Energies	Publication Date: Sep 27, 2019
Citations: 5	License type: CC BY 4.0

Affiliation: Silesian University of Technology

Abstract

Currently, there is a lot of interest in implementing the idea of a circular economy along with searching for optimal methods of waste management in terms of raw materials and energy. Waste wood-based floor panels are part of this discussion with regard to its management. The interest in this waste results from statistics and the prediction of its future quantities on the waste market. The separation and testing of individual layers of the waste floor panel was undertaken to answer the following question: Is it reasonable to mechanically separate the contaminated upper panel layer from the remaining part (which is suitable for material recycling) and subject it to thermal transformation methods? Thermogravimetric studies did not confirm the rationale of mechanical separation of layers for further management. Therefore, the use of pyrolysis was proposed as an alternative by showing the advantages of this process in the thermal transformation of the tested waste. The analyzed kinetics of this process included: mass loss, the influence of heating rate on the decomposition process, the impact of volatile parts in the substrate on the rate of mass loss, and the share of coke residue. Empirical formulas of the tested substrates in the molecular formula C–H–O–N (carbon-hydrogen-oxygen-nitrogen) were also proposed to assess its energy usefulness by entering the analyzed waste into a Van Krevelen diagram.

Highlights

It is estimated that more than 10 million m3 of various types of wood materials are currently produced in Poland, over 3.5 million m3 of which are MDF and HDF [1].At a time of great emphasis on the recovery of materials according to the idea of a circular economy (CE) and following the hierarchy of waste management with regard to the post-consumer wood waste, such as floor panels, two options for their management were considered as below [2,3,4,5]: mechanical and thermal method, thermal method.The proposed methods fit into the idea of a circular economy, whose most important assumptions are presented below
It is difficult to determine clearly what is the thermal effect of the pyrolysis itself, and what are the effects of secondary reactions occurring between pyrolytic gases and the surface of the char [13]
The difference among the thermal effects for wood and charcoal relates to pyrolysis heat, and it amounts to 1473 kJ/kg

Summary

Introduction

It is estimated that more than 10 million m3 of various types of wood materials are currently produced in Poland, over 3.5 million m3 of which are MDF (medium-density fiberboard) and HDF (high-density fiberboard) [1]. The Polish legislation requires the combustion of pyrolysis products, there are other ways to use these raw materials, such as for example in the production of methanol: R3 Recycling or the recovery of organic substances that are not used as solvents (including composting and other biological transformation processes). This heading includes gasification and pyrolysis using these components as chemical reagents [2]. This status can be changed subsequently through operations such as drying, mechanical drainage, heating, etc. in order to enhance energy properties (mainly calorific value by improving the ratio of fuel elements h/c (hydrogen/carbon) and o/c (oxygen/carbon))

Thermodynamic and Kinetic Aspects of Pyrolysis

Heat Demand for the Pyrolysis Process

Kinetics of the Pyrolysis Process

Van KREVELEN Systematics and Wood-Based Waste

Van KREVELEN and

Materials and Methods

Discussion