Significant investment into research is ongoing to develop commercially viable processes. The New Zealand Lignocellulosic Bioethanol Initiative (LBI) was one such Collaborative Research Project between New Zealand Forest Research Limited (Trading as Scion), Verenium, BP and Beca AMEC.
The initiative was aimed at utilising softwood wood chips as a feedstock for the production of bioethanol. Currently, New Zealand only produces bioethanol from whey. The ultimate raw material is likely to be forest residues and wood waste.
Beca AMEC’s role in the consortium managed by Scion was to provide engineering resources where appropriate and participate in technical and management committees. A macro model for bioethanol manufacture via a biochemical pathway was developed, initially based on a mechanical pulping process.
This model encompassed mass and energy flows through the process.
Three technology options were considered and modelled. The modelling quantified raw material inputs, the equipment sizing, and the ethanol generation. This in turn meant that operating cost and capital costs were formulated for the favoured options.
Further development of the favoured option has been the next stage of the process with scale-up to pilot plant trials to demonstrate the concepts as a primary goal. Scion had a very intense laboratory programme to evaluate the process variables, and address the challenges of softwood processing.
Beca AMEC’s role in the next stage of development has been to build a more robust model in IDEAS™ software to track multiple components through the various unit operations of raw material ‘treatment’, enzymatic hydrolysis, fermentation and distillation. Laboratory analyses were used
to validate the soluble sugar split at key process steps and improve the integrity of the model. The model in turn generated operating costs and allowed the science to be optimised and ‘steered’ towards the best economic outcome. The work is continuing through a three year programme.