Helmholtz Virtual Institute for Gasification Technology - HVIGasTech
Bach-Oller LTU

Albert Bach-Oller

Research topic
Alkali-enhanced gasification of biomass: Laboratory-scale experimental studies

Postdoctoral position at the division of energy science at Lueå Univeristy of Technology

• Experimental work with lab-scale gasification of biomass
• Alkali-enhanced gasification
• Hydrothermal liquefaction of biomass and wastes
• Analytic chemistry applied to biomass

Gasification seeks to break carbonaceous materials into raw synthetic gas (CO+H2) which can be subsequently upgraded into valuable products. Thus, gasification can be utilized to convert low-grade biomass stocks into carbon-neutral chemicals, heat and power. Nonetheless, gasification generates tar and soot as a by-products, impurities which deposit on cold surfaces and catalyst beds, risking operation downstream of the gasifier. Although methods to clean the gas are available, it is preferable to tackle, in the first place, the formation of tar and soot in its origin in the gasifier. One method to do that is by exploiting the unique properties of alkali elements. Alkali elements possess a catalytic activity on char gasification, but more importantly, alkali has a very strong suppression effect of soot. Yet, to design a functional alkali-enhanced gasification process we need to investigate in more detail on what exact products does alkali show an activity on, on what stage, under what circumstances and, on the measure that it is possible, the mechanism.
My research addresses these questions by means of laboratory-scale experiments with well-controlled conditions. In the past, we have approached the topic from different sides. On the one hand, we studied the effects of diluting the alkali content of a Na-rich black liquor (BL) by blending it with pyrolysis oil (PO), and on the other hand, we investigated adding various amounts of alkali into more conventional types of biomass fuels. More recently, we have expanded that research line to explore the effect of alkali in the hydrothermal liquefaction of biomass, and its potential integration with entrain flow gasification.

Industrial Engineering, Universitat Politecnica de Catalunya (UPC)

PhD-Thesis: Alkali-enhanced gasification of biomass: Laboratory-scale experimental studies, 2018

Degree, year

Researcher's Homepage at partner institution


Yields of carbon in the various sources of impurities expressed as a fraction of the carbon in the fuel. T=1000 °C and 5 % CO2. Error bars show 1 standard deviation. N=3. The results were obtained in the experimental campaign nr.6