Residual moisture in the sewage sludge feed significantly affects the pyrolysis process: Simulation of continuous process in a batch reactor.

0548934 - ÚCHP 2023 RIV NL eng J - Článek v odborném periodiku
Moško, Jaroslav - Jeremiáš, Michal - Skoblia, S. - Beňo, Z. - Sikarwar, Vineet Singh - Hušek, Matěj - Wang, H. - Pohořelý, Michael
Residual moisture in the sewage sludge feed significantly affects the pyrolysis process: Simulation of continuous process in a batch reactor.
Journal of Analytical and Applied Pyrolysis. Roč. 161, JAN 2022 (2022), č. článku 105387. ISSN 0165-2370. E-ISSN 1873-250X
Grant CEP: GA MZe(CZ) QK21020022
Grant ostatní: AV ČR(CZ) StrategieAV21/3
Program: StrategieAV
Institucionální podpora: RVO:67985858 ; RVO:61389021
Klíčová slova: sewage sludge * pyrolysis * gasification * gas composition
Obor OECD: Energy and fuels; Energy and fuels (UFP-V)
Impakt faktor: 6, rok: 2022
Způsob publikování: Open access s časovým embargem

In the experiments presented within this manuscript, we allowed the residual moisture typical for industrially dried sludge (10 wt%) to react within the pyrolysis process by incorporating it into the carrier gas (consisting finally of 70 vol% steam and 30 vol% He). This steam reacted within the pyrolysis process at temperatures 400–800 °C in a fixed-bed reactor. The results were thoroughly compared with the results of a previous study with pure helium atmosphere, within the same experimental setup. When comparing the experiments with and without steam in the carrier gas, a significant difference in the distribution and properties of the products was observed especially at temperatures above 600 °C. The use of steam as a carrier gas (instead of inert gas) resulted in a remarkably higher pyrolysis gas yield. The pyrolysis gas constituted of almost double the content of hydrogen with a decrease in the yield of the sludge-char. Moreover, particular changes in sludge-char properties were observed. Not only the steam enhanced textural properties of the sludge-chars, especially the specific surface area and the total specific pore volume, but it also resulted in a significantly lower content of C, H, N and S and lower heating value of the sludge-char. These parameters can be decisive in case of sludge-char utilization ranging from agronomic through adsorbents to fuel use. Our approach provides a simplified way to better predict the distribution and properties of pyrolysis products in large-scale units. This can be time and money saving and is crucial to make decisions about the applicability of pyrolysis technology to specific sewage sludge products.
Trvalý link: http://hdl.handle.net/11104/0324977