EUBCE 2024 - Malgorzata WZOREK - Valorization of Spent Coffee Grounds for Energy Applications

Valorization of Spent Coffee Grounds for Energy Applications

Short Introductive summary

The paper presents a proposed technological line that includes a proprietary solar drying method, pelletizing, and torrefaction, which allows to prepare of spent coffee grounds for application in energy processes. The first stage of the pretreatment of spent coffee grounds involved the use of solar drying. Tests were conducted in a solar greenhouse dryer equipped with a specially designed mixing system to determine the drying time and thickness of the layer of dried spent coffee grounds in weather conditions in the southwestern part of Poland. The dried spent coffee grounds with a moisture content of about 10% were then subjected to the pelletization process. Additionally, a portion of the produced pellets underwent torrefaction to compare their energetic and mechanical properties. The torrefaction of samples was done in the laboratory scale rotary reactor. Testes was done in the range of temperature 240-300oC and time 30-40 min in N2 atmosphere. Additionally, thermogravimetry (TG-DTA) coupled with Fourier transform infrared spectroscopy (FTIR) was used to investigate the differences in combustion process for raw pellets and pellets after torrefaction. The reaction regions, initia

M. Wzorek, Opole University of Technology, POLAND
R. Junga, Opole University of Technology, POLAND
E. Yilmaz, Adnan Menderes University, Aydin, TURKEY
H. Unyay, Lodz University of Technology, POLAND
S. Szufa, Lodz University of Technology, POLAND