Development of a 10 Kw Microwave Applicator for Thermal Cracking of Lignite Briquettes

Abstract

A compact 10 kW microwave applicator operating at 2.45 GHz for fast volumetric heating and thermal cracking of lignite briquettes has been successfully designed and tested. In this paper, the applicator design and construction are presented together with a sequentially coupled electromagnetic, thermal-fluid and mechanical Comsol model. In a first step, this model allows us to calculate the power density inside the lignite material and the temperature distribution in the applicator for different water flow rates. In a second step, the total stress due to the thermal dilatation, the internal pressure inside the ceramic and the contact pressure from the seals at both ends of the ceramic can be computed. In addition, preliminary experimental results are given and showed a significant mechanical strength weakening of the briquettes with microwave heating.

Characterisation of briquettes from forest wastes: Optimisation approach

“…This waste could serve as a feedstock for the production of solid fuels, such as briquettes (Gwenz et al 2020;. Briquettes have been produced from agricultural waste, such as corn cobs (Muazu and Stegemann 2017), tea waste (Demirbas 1999), rice bran (Olugbade and Mohammed 2015), corn stalks, cotton stalks, wheat straw, https://doi.org/10.17221/6/2021-RAE lignite (Gürbüz-Beker et al 1998;Yaman et al 2001;Lepersa et al 2015), fruit branches, sugar cane waste (bagasse), and palm kernel shells (Chou et al 2009;Zhongqing et al 2015;Oke et al 2016) to mention but a few. Moreover, in Nigeria, several projects have been embarked upon on the use of jatropha for the production of biodiesel (Fadele et al 2012).…”