Research interests + projects
My research interest is in the area of resource recovery from different types of waste biomass, focusing on two major sub-areas: 1) Biomass feedstock engineering, and 2) Bioconversion processes and systems.
Biomass feedstock engineering
Research activities include the preprocessing and pretreatment of under-utilized lignocellulosic waste biomass that includes forest residues, crop residues, and urban wood waste to produce high quality solid biofuel (fuel pellets) for heat and power generation, as well as the storage, handling, and transport of the biomass in both densified and non-densified forms. These constitute the main components of the supply chain logistics, which bridges the gap between biomass harvesting and bioenergy production in different types of biomass conversion facilities. The overall strategy associated with the research is to provide the bioenergy industry with a reliable and cost-effective supply of high-quality solid biofuel. Current projects aim at improving the physicochemical and fuel properties of waste biomass to meet the international standards for fuel pellet quality, and developing best practices to minimize the degradation of biomass during storage and handling.
Bioconversion processes and systems
Research activities are primarily focused on aerobic composting and anaerobic digestion of non-woody biomass/organic wastes. Composting constitutes an important component in today’s integrated solid waste management approach. Woody residuals that are separated from the finished compost product can also be pretreated to produce high quality fuel pellets. Anaerobic digestion of organic wastes for biogas production and upgrading the biogas to biomethane (renewable natural gas) have environmental benefits in terms of reduced greenhouse gas and odour emissions. Current projects aim at improving the performance of the anaerobic digestion process through co-digestion of organic waste mixtures, using biocatalyst, and minimizing the inhibitory metabolites during the digestion process. Research is extended to the recovery of the macro-nutrients from the anaerobic digestate.
Scholarly and professional activities + affiliations
Selected publications + presentations
Lee J., Ghiasi B., Lau A.K., Sokhansanj S. Chlorine and ash removal from salt-laden woody biomass by washing and pressing. Biomass and Bioenergy 155, 6 pp. (2021) https://doi.org/10.1016/j.biombioe.2021.106272
Yu Y., Wu J., Ren X., Lau A., Rezaei H., Takada M., Bi X., Sokhansanj S. Steam explosion of lignocellulosic biomass for multiple advanced bioenergy processes: a review. Renewable and Sustainable Energy Reviews 154, 19 pp. (2022) https://doi.org/10.1016/j.rser.2021.111871
Peng Y., Lau A.K. Improving the quality of crop residues by the reduction of ash content and inorganic constituents, Journal of Biobased Materials and Bioenergy 14(2): 209-219. (2020) https://doi.org/10.1166/jbmb.2020.1950
Rezaei H., Lim C.J., Lau A.K., Sokhansanj S. 2016. Size, shape and flow characterization of ground wood chip and ground wood pellet particles, Powder Technology 301: 737-746. (2016) http://dx.doi.org/10.1016/j.powtec.2016.07.016
He X., Lau A.K., Sokhansanj S., Lim C.J., Bi X.T., Melin S. Investigating gas emissions and dry matter loss from stored biomass residues. Fuel 134: 159-165. (2014) http://dx.doi.org/10.1016/j.fuel.2014.05.061