TY - JOUR
T1 - Tar from pilot scale co-pyrolysis of biological dairy sludge and spruce wood chips
AU - Horvat, Alen
AU - Kwapinska, Marzena
AU - Leahy, James J.
N1 - Publisher Copyright:
© 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/)
PY - 2019
Y1 - 2019
N2 - A pilot scale investigation of co-pyrolysis of biological dairy sludge and spruce wood chips and pyrolysis of spruce wood chips solely was carried out. Pyrolysis was tested as a waste treatment method aiming to reduce the volume of dairy sludge while producing a pyrolysis gas suitable for an internal combustion engine. Pyrolysis tests were carried out in a continuously fed, pilot scale rotating retort type of facility in the temperature range between 700 and 770 °C. Feedstock feeding rates were between 40.9 - 68.6 kgd.a.f. h-1. Tar yields and composition was measured by means of the solid phase adsorption method in order to assess gas quality with regard to the specified tar limits given for downstream applications. The yields of total gas chromatography detectable tar produced from the dairy sludge and spruce wood chips blend was in the range between 7.25 - 10.98 gtotal tar Nm-3 dry raw gas, while spruce wood chips solely produced yields between 11.18 - 13.31 gtotal tar Nm-3 dry raw gas. Composition wise, the main difference was a number of nitrogen-containing tar compounds reflecting the high nitrogen content in dairy sludge feedstock with 2-butenenitrile, pyridine and 1H-pyrrole being the most abundant nitrogen-containing tar compounds. Raw pyrolysis gas from the two feedstocks tested did not meet the requirements regarding tar limits given in the manufacturer's specification for their internal combustion engine. The raw pyrolysis gas contained excessive amounts of 3 and 4+ aromatic ring tars. Therefore tar removal is required prior to combustion in the engine. The proposed tar removal strategy includes a thermal tar reformer using air as a reforming agent followed by adsorption using wood chips, or in-process generated bio-char, or torrefied biomass as a viable adsorbent.
AB - A pilot scale investigation of co-pyrolysis of biological dairy sludge and spruce wood chips and pyrolysis of spruce wood chips solely was carried out. Pyrolysis was tested as a waste treatment method aiming to reduce the volume of dairy sludge while producing a pyrolysis gas suitable for an internal combustion engine. Pyrolysis tests were carried out in a continuously fed, pilot scale rotating retort type of facility in the temperature range between 700 and 770 °C. Feedstock feeding rates were between 40.9 - 68.6 kgd.a.f. h-1. Tar yields and composition was measured by means of the solid phase adsorption method in order to assess gas quality with regard to the specified tar limits given for downstream applications. The yields of total gas chromatography detectable tar produced from the dairy sludge and spruce wood chips blend was in the range between 7.25 - 10.98 gtotal tar Nm-3 dry raw gas, while spruce wood chips solely produced yields between 11.18 - 13.31 gtotal tar Nm-3 dry raw gas. Composition wise, the main difference was a number of nitrogen-containing tar compounds reflecting the high nitrogen content in dairy sludge feedstock with 2-butenenitrile, pyridine and 1H-pyrrole being the most abundant nitrogen-containing tar compounds. Raw pyrolysis gas from the two feedstocks tested did not meet the requirements regarding tar limits given in the manufacturer's specification for their internal combustion engine. The raw pyrolysis gas contained excessive amounts of 3 and 4+ aromatic ring tars. Therefore tar removal is required prior to combustion in the engine. The proposed tar removal strategy includes a thermal tar reformer using air as a reforming agent followed by adsorption using wood chips, or in-process generated bio-char, or torrefied biomass as a viable adsorbent.
KW - Dairy processing sludge
KW - Pyrolysis
KW - Tar
KW - Waste treatment
UR - http://www.scopus.com/inward/record.url?scp=85064452633&partnerID=8YFLogxK
U2 - 10.1016/j.egypro.2019.02.059
DO - 10.1016/j.egypro.2019.02.059
M3 - Conference article
AN - SCOPUS:85064452633
SN - 1876-6102
VL - 161
SP - 66
EP - 74
JO - Energy Procedia
JF - Energy Procedia
T2 - 2nd International Conference on Sustainable Energy and Resource Use in Food Chains, ICSEF 2018
Y2 - 17 October 2018 through 19 October 2018
ER -