Effect of Torrefaction Temperature, Residence Time and Particle Size on the Properties of Torrefied Food Waste

Abstract

Municipal solid waste (MSW) in Malaysia mainly consists of food waste. As food waste is of organic compounds, its improper management may cause serious environmental issues, as it may produce greenhouse gases and polluting leachate. Alternative management of the food waste is through its utilization. However, the main issue in the utilization of food waste is its heterogeneity, whereby the diversified cooking methods, as well as food origin, emanates different characteristics. Hence, food waste needs to be pre-treated through the torrefaction process, which is a thermochemical method that converts it to biochar at a temperature between 200–300 °C in an inert environment. The main aim of this work is to evaluate the feasibility of food waste as a potential source of energy through the torrefaction process. The torrefaction of food waste was conducted in a vertical tubular reactor under an inert atmosphere. The results obtained from this study showed that as torrefaction temperature became more severe, the produced torrefied solid is more energy-dense, with apparent higher fixed carbon content and improved heating values. These findings imply that food waste may be able to be utilized as a solid biofuel, with fuel properties comparable to conventional fuels.

Upgrading Characteristics of Empty Fruit Bunch Biopellet with Addition of Bintaro Fruit as Co-firing

“…The reduction of moisture content and volatile content during the reaction will automatically increase the fixed carbon content in biomass (Tumuluru et al, 2010). Similar results were also obtained by Rasid et al (2019) and Thaim and Rasid (2016) that the fixed carbon content is linear to the residence time.…”

“…Ash content is also due to impurities external such as clay and sand. Similar results were also obtained by Rasid et al (2019) that the longer residence time would produce higher ash content.…”

“…So that the longer residence time causes the maximum devolatilization process (Tumuluru et al, 2010). Similar results were also obtained by Strandberg et al (2015) and Rasid et al (2019) that the longer residence time causes reduced volatile content.…”

“…Similar results were also obtained by Chen et al (2014) that moisture content inversely to residence time. Likewise with the results by Rasid et al (2019) about characteristics of torrefaction products from food waste. The result shows that the lowest moisture content is obtained under conditions of residence time 60 minutes in the range of 15 -60 minutes.…”

The Effects of Additives on the Pelletization of Raw and Torrefied Food Waste

“…The torrefied biomass possesses coal-like properties and may potentially replace coal as solid fuel in the future. There have been many studies on biomass torrefaction [8], espcially the ones focusing on FW [4], [9], [10]. However, these studies focused solely on the torrefaction, having determined that like other biomass, the fuel properties improved with increasing temperature, though they are not too affected by the residence time of more than 30 minutes.…”