Biocoal - Quality control and assurance

Abstract

Torrefied biomass is said to have potential as a replacement for coal. One of the main goals of torrefaction is to make biomass resemble coal more in terms of its properties as a solid fuel. As a fuel, a novel fuel that is produced by thermal treatment of raw biomass, biocoal has to comply with the regulations of solid fuels from different regulatory bodies. The production regime is different in comparison to the thermally treated fuel already established on the market, such as charcoal. This might raise an issue with the bodies controlling the circulation of chemical substances in the market, such as ECHA in Europe. The aim of this paper is to recommend suitable analytical techniques in order to enable effective quality control. This is necessary if biomass of low and highly variable quality is supposed to become more uniform and turn into a commodity. Information given in many published studies seems sufficient to use of FTIR and NIR as quality control techniques. The use of NMR can be complementary but is limited due to the high cost of the analytical equipment and time-consuming sample preparation. Rapid testing techniques, such as FTIR ATR or NIR, might prove feasible for quality control of solid biofuels, such as biocoal, especially for in-house quality control purposes. This way proper quality assurance and compliance with various novel regulations, such as REACH, could be assured. Further research could be helpful, especially if results would be available in publicly available databases, such as Phyllis.

Densification of agro-residues for sustainable energy generation: an overview

“…Due to the renewed global interest in the development of alternative and environmentally friendly fuels from biomass feedstock to serve as a substitute to conventional fuels, great research efforts have been put into the investigation of factors that influence the physical, mechanical, chemical or compositional, combustion and thermal properties of solid fuels manufacture using biomass as feedstock (Ajimotokan et al 2019c ; Junga et al 2021 ; Berdychowski et al 2021 ; Thapa and Engelken 2019 ). These factors includes but not limited to moisture content (Berdychowski et al 2021 ; Yang et al 2021 ), particle size distribution (Olatunji et al 2020 ; Matkowski et al 2020a ), process temperature (Berdychowski et al 2021 ; Yang et al 2021 ; Riva et al 2019 ), present of additives(Song et al 2019 ), blending of feedstock (Junga et al 2021 ; Thapa and Engelken 2019 ), co-blending feedstock with coal, feedstock origin, compaction pressure (Ajimotokan et al 2019c ; Berdychowski et al 2021 ; Yang et al 2021 ; Song et al 2021 ) and thermal pretreatment (Kang et al 2020 ; Martín et al 2020 ; Pawlak-kruczek et al 2020 ). A detailed review of different factors that affect solid fuel quality can be found in Gilvari et al ( 2019 ).…”

Influence of Torrefaction and Pelletizing of Sawdust on the Design Parameters of a Fixed Bed Gasifier

“…Closed containers were subsequently inserted into hot laboratory furnace, pre-heated to 300 • C. Torrefaction was performed, in duplicate, with two distinct residence times of 15 min and 30 min, in order to obtain distinctly different samples, with respect to the severity of the torrefaction process. Temperature and residence time were selected based on a typical range of torrefaction conditions, reported in the literature [4,8,[23][24][25][26][65][66][67][68]. Selection of the temperatures from the higher end and residence time from lower end of reported conditions was dictated by the way these parameters influence productivity of torrefaction reactors.…”

“…It is a process that is considered to improve the logistics and handling of the upgraded fuel [5][6][7][8][9][10] and make it more suitable for final use, such as co-firing [11][12][13] or gasification [14][15][16]. Torrefaction is 2 of 19 sometimes called slow pyrolysis and it typically takes place at temperatures between 250 • C and 300 • C with residence times ranging between 10 min and 60 min [4,[17][18][19][20][21][22][23][24][25][26]. During torrefaction, part of the mass of the feedstock is removed.…”

Is Biochar from the Torrefaction of Sewage Sludge Hazardous Waste?

“…However, only 16 papers included both "torrefaction" and "sewage sludge" in the title. As the SS torrefaction technology is developing, researchers are focusing on the optimization of the process parameters and the improvement of the fuel properties of the biochar [7,8]. Previous studies indicated that both raw and torrefied SS have average fuel properties [4,6].…”