Search
Synergism of floated paperboard sludge cake /sewage sludge for maximizing biomethane yield and biochar recovery from digestate: A step towards circular economy
Abstract
Anaerobic digestion of floated paperboard sludge (PS) cake suffers from volatile fatty acids (VFAs) accumulation, nutrient unbalanced condition, and generation of digestate with a risk of secondary pollution. To overcome these drawbacks, sewage sludge (SS) was added to PS cake for biogas recovery improvement under a co-digestion process followed by the thermal treatment of solid fraction of digestate for biochar production. Batch experimental assays were conducted at different SS:PS mixing ratios of 70:30, 50:50, 30:70, and 20:80 (w/w), and their anaerobic co-digestion performances were compared to the mono-digestion systems at 35±0.2 °C for 45 days. The highest methane yield (MY) of 241.68±14.81 mL/g CODremoved was obtained at the optimum SS:PS ratio of 50:50 (w/w). This experimental condition was accompanied by protein, carbohydrate, and VFA conversion efficiencies of 47.3±3.2%, 46.8±3.2%, and 56.3±3.8%, respectively. The synergistic effect of SS and PS cake encouraged the dominance of Bacteroidota (23.19%), Proteobacteria (49.65%), Patescibacteria (8.12%), and Acidovorax (12.60%) responsible for hydrolyzing the complex organic compounds and converting the VFAs into biomethane. Further, the solid fraction of digestate was subjected to thermal treatment at a temperature of 500 °C for 2.0 h, under an oxygen-limited condition. The obtained biochar had a yield of 0.48 g/g dry digestate, and its oxygen-to-carbon (O/C), carbon-to-nitrogen (C/N), and carbon-to-phosphorous (C/P) ratios were 0.55, 10.23, and 16.42, respectively. A combined anaerobic co-digestion/pyrolysis system (capacity 50 m3/d) was designed based on the COD mass balance experimental data and biogenic CO2 market price of 22 USD/ton. This project could earn profits from biogas (12565 USD/yr), biochar (6641 USD/yr), carbon credit (8014 USD/yr), and COD shadow price (6932 USD/yr). The proposed project could maintain a payback period of 6.60 yr. However, further studies are required to determine the associated life cycle cost model that is useful to validate the batch experiment assumptions.
Citations
-
1
CrossRef
-
0
Web of Science
-
1
Scopus
Authors (8)
-
Rania H. Hafez dr
- National Research Center in Egypt
-
Ahmed Tawfik dr
- Kuwait University
-
Gamal K. Hassan
- National Research Center in Egypt
-
Magdy Zahran dr
- Helwan Univeristy
-
Ahmed A. Younes
- Helwan Univeristy
-
Aleksandra Ziembińska-Buczyńska
- Silesian University of Technology
-
Mahmoud Nasr dr
- Alexandria University
Cite as
Full text
full text is not available in portal
Keywords
Details
- Category:
- Articles
- Type:
- artykuły w czasopismach
- Published in:
-
CHEMOSPHERE
no. 362,
ISSN: 0045-6535 - Language:
- English
- Publication year:
- 2024
- Bibliographic description:
- Hafez R. H., Tawfik A., Hassan G. K., Zahran M., Younes A. A., Ziembińska-Buczyńska A., Gamoń F., Nasr M.: Synergism of floated paperboard sludge cake /sewage sludge for maximizing biomethane yield and biochar recovery from digestate: A step towards circular economy// CHEMOSPHERE -,iss. 142639 (2024),
- DOI:
- Digital Object Identifier (open in new tab) 10.1016/j.chemosphere.2024.142639
- Sources of funding:
-
- Free publication
- Verified by:
- Gdańsk University of Technology
seen 54 times
Recommended for you
Valorization of paper-mill sludge laden with 2-chlorotoluene using hydroxyapatite@biochar nanocomposite to enrich methanogenic community: A techno-economic approach
- R. H. Hafez,
- A. Tawfik,
- G. K. Hassan
- + 5 authors
Nanoparticle-assisted biohydrogen production from pretreated food industry wastewater sludge: Microbial community shifts in batch and continuous processes
- M. Saad Hellal,
- F. Gamoń,
- G. Cema
- + 3 authors