Simultaneous biogas upgrading, CO2 sequestration, and biogas slurry decrement using biomass ash. (September 2021)

• Record Type: Journal Article
• Authors: Feng, Liang; Liang, Feihong; Xu, Lang; Ji, Long; He, Qingyao; Yan, Shuiping
• Is Part Of: Waste management. Volume 133(2021)
• Page Start: 1
• Page End: 9
• Publication Date: 2021-09
• Subjects: Biogas -- Bio-methane -- CO2 absorption -- CO2 sequestration -- Agricultural application; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2021.07.029
• Languages: English
• ISSNs: 0956-053X

Abstract

Graphical abstract: Highlights: A novel system for CO2 sequestration and biogas slurry decrement is put forward. A high CO2 sequestration capacity of 129.94 g-CO2 /kg is acquired. The CO2 -rich biomass ash and biogas slurry mixture is applied for plant growth. Abstract: A novel system for simultaneous biogas upgrading, CO2 sequestration, and biogas slurry decrement was established by adding biomass ash into biogas slurry to form a renewable CO2 mixture absorbent. After CO2 saturation, the CO2 -rich mixture absorbent could be applied for plant growth. When the mass ratio of liquid to solid was 4:1, CO2 absorption capacity of this mixture absorbent reached up to 97.33 g-CO2 /kg-biomass-ash, which was about 135% higher than that of the biomass ash-water mixture. The highest value of 129.94 g-CO2 /kg-biomass-ash was obtained at a liquid–solid ratio of 99:1. When the TS concentration of anaerobic digestion feedstock was higher than 16 wt% and the water content of CO2 -rich absorbent was about 50 wt%, more than 80% of biogas slurry can be adsorbed by the biomass ash. If the biomass ash with a CO2 absorption capacity of 100 g-CO2 /kg was adopted and its transportation distance was less than 45 km, the biogas upgrading cost could be lower than the global average level (about RMB¥ 0.7/Nm 3 -biogas) when using the novel system proposed in this study.