Paper details

Title:

Coupling Biogas Upgrading in Bubble Column Reactors and Anaerobic Digestion: an Experimental Study on CO₂ Absorption Using NaOH Solutions Based on Laboratory Tests Supporting the Pilot Plant Design

Author(s):

Asquer, C., Melis, E., Scano, E.A.

Document(s):

Abstract:

This paper describes a system composed by a pilot anaerobic digester and an upgrading pilot plant, designed by the Biofuels and Biomass Laboratory of Sardegna Ricerche (Sardinia, Italy). The system allows to obtain a stream of biomethane (purity >95%) from local residual biomass, such as fruits and vegetable wastes, agroindustry by-products or crop residues. The general objective of the work is to design a biogas upgrading pilot plant coupled with the anaerobic digester already operating at the Biofuels and Biomass Laboratory, which produces up to 2 m3·d-1 of biogas. The specific objective of this work is to obtain a biomethane flow having a CH4 concentration higher than 95%vol (as per the Italian regulation), aimed at storing gas and injecting into natural gas networks. To design the pilot upgrader, a set of experiments was carried out on a laboratory scale, to assess the CO2 absorption efficiency of different NaOH solutions in a lab-scale bubble column reactor. The first absorption laboratory tests involved three NaOH solutions and three biogas flow rates. The subsequent tests consisted in flowing continuously the biogas at the maximum flow rate, identified during the previous upgrading trials, to determine the time necessary to reach a CH4 concentration higher than that expected (95%vol).

Keywords:

biogas, methane, upgrading, absorption, carbon dioxide (CO₂), bubble column reactors

Topic:

Biomass Technologies and Conversion for Bioenergy

Subtopic:

Anaerobic digestion for biogas and biomethane production

Event:

28th European Biomass Conference and Exhibition

Session:

2CV.5.36

Pages:

498 - 506

ISBN:

978-88-89407-20-2

Paper DOI:

10.5071/28thEUBCE2020-2CV.5.36

Price:

FREE