Reduction of tar generated during biomass gasification: A review

• Published in: Biomass & bioenergy Vol. 108; pp. 345 - 370
• Main Authors: Valderrama Rios, Martha Lucia, González, Aldemar Martínez, Lora, Electo Eduardo Silva, Almazán del Olmo, Oscar Agustin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-01-2018
• Subjects: Biomass gasification; Catalytic cracking; Tar cleaning systems; Tar conversion; Tar formation; Tar formation; Biomass gasification; Tar cleaning systems; Tar conversion; Catalytic cracking
• ISSN: 0961-9534; 1873-2909
• DOI: 10.1016/j.biombioe.2017.12.002

One of the main problems that happen during biomass gasification is tar formation, which could make this technology unsuccessfully from a commercial point of view. Tar content present in syngas defines its application, considering that limits - according to desired application - can be very demanding. There are two ways to overcome this problem: by optimizing gasification operation conditions and removal of tar from gas through in-situ (primary methods) or post-gasification (secondary methods) treatments. This way, multiple technologies have been developed considering the balance between efficiency and economy of the process, besides being (ecofriendly) environmentally acceptable. Some aspects related to tar formation, laboratory and industrial methods and technologies for its reduction-removal, as well as research and development in this area are reviewed and evaluated in this paper.
•Formation, chemical composition and tar classification were reviewed.•Formation and tar conversion pathways have been addressed.•A comprehensive review of tar cleaning methods for product gas is presented.•Performance of different methods for tar reduction - removal at laboratory and industrial level were discussed.•Use low cost catalysts and residual materials have capacity to produce clean syngas.