Mass and energetic yields of hydrochar from brewer’s spent grain

J. Velebil*, J. Malalák and J. Bradna

Czech University of Life Sciences Prague, Faculty of Engineering, Department of
Technological Equipment of Buildings, Kamýcká 129, CZ 165 21 Prague, Czech Republic
*Correspondence: velebil@tf.czu.cz

Abstract:

Brewer’s spent grain (BSG) was hydrothermally carbonized at combinations of three temperatures (180 °C, 215 °C, 250 °C) and three reaction times (2 h, 5 h, 12 h). For comparison, the corresponding barley malt was also tested at the same conditions. Elemental composition, volatile matter, ash and heating values were determined for original biomasses as well as resulting hydrochars. The mass yield of dry BSG hydrochar ranged from 45 to 73%. The energetic yield defined as retention of total lower heating value in the hydrochar on dry basis ranged from 66 to 85%. Specific lower heating value of dry material rose from 20.6 MJ kg^-1 to 30.3 MJ kg^-1 at the most severe conditions. Nitrogen and sulphur content in hydrochar were not strongly dependent on reaction conditions.

Key words:

Investigations of fibre plants preparation and utilization of solid biofuels

D. Streikus¹, A. Jasinskas¹*, M. Arak², E. Jotautienė1, R. Mieldažys¹, S. Čekanauskas³ and Z. Jankauskienė⁴

¹Aleksandras Stulginskis University, Faculty of Agricultural Engineering, Institute of
Agricultural Engineering and Safety, Kaunas-Akademija, Studentu str. 15A, LT-53361
Kaunas r., Lithuania
²Estonian University of Life Sciences, Institute of Technology, Fr.R. Kreutzwaldi 56,
EE51014 Tartu, Estonia
³Aleksandras Stulginskis University, Experimental Station, Kaunas-Akademija,
LT-53361 Kaunas r., Lithuania
⁴Lithuanian Research Centre for Agriculture and Forestry, Upyte Experimental Station,
Linininku str. 3, Upyte, LT-38294 Panevezys r., Lithuania
*Correspondence: algirdas.jasinskas@asu.lt

Abstract:

Presented research results of technological-technical means and operations for solid biofuel preparation: chopping, milling, pelleting and burning of fibre plants – 3 sorts of fibre hemp (Beniko, Bialobrzeskie and Epsilon 68) and fibre nettle (sown in 60 x 60 cm). These fibre plants were grown in the experimental fields of Lithuanian Research Centre for Agriculture and Forestry, Upytė Experimental Station, and in Aleksandras Stulginskis University were investigated the technical means of these plants preparation and usage for energy purposes. It was used the standard methodology for solid biofuel preparation of fibre plants, and was investigated the technique for plant chopping, milling and pelleting. There were determined fibre plant mill fractional composition while usage the hummer miller prepared mill. There were determined the fibre plant pellet quality indicators – moisture content and bulk density. The fibre plant pellet moisture content ranged from 6.4% to 8.8%, and pellet density reached 1,082.7–1,186.2 kg m^-3 DM (dry matter). Pellet elemental composition, ash content and calorific value were determined at the Lithuanian Energy Institute. The ash content after the burning of fibre plant pellet was not high and varied from 3.6 to 5.9%. Determined net calorific value of fibre hemp and fibre nettle dry mass was relatively high 17.2–17.5 MJ kg^-1, it was close to calorific value of some wood species.

Key words:

ash content., calorific value, elemental composition, Fibre hemp, fibre nettle, pellets