Borregaard’s BALI process reaches Technical Readiness Level 7 as BIOFORVER project advances: report
In Norway, the BALI demonstration plant operated by the BIOFOREVER project reports that the successful scale-up from lab by a factor of 1000 and several years of operation in a semi-commercial scale suggests that the BALI technology is at TRL (Technology Readiness Level) 6-7.
In September 2016 a consortium of 14 European companies started the BIOFOREVER project in order to demonstrate the commercial viability of a number of value chains from woody biomass to value adding chemical building blocks. Since then the focus has been on providing wood samples (spruce, poplar and A-wood) to the 4 technology partners in order to optimize the sugar quality output a.o. from their pre-treatment technology. One of the technologies used is Borregaard’s BALI technology.
Compared to Borregaard’s traditional sulfite mill, the BALI process produces only two products – lignin and sugar – instead of four (cellulose specialty pulp, lignin performance chemicals, vanillin and bioethanol). Woody feedstock is subjected to a sulfite pretreatment which renders the lignin water soluble. This is a unique feature of the BALI process as it allows easy separation of the lignin from the cellulose fraction early in the process.
After washing of the pulp, cellulase enzymes are added in order to hydrolyze the pulp. After separation of any residual unhydrolyzed particles the hydrolysate is either used as is, or subjected to evaporation for concentration. The BALI hydrolysates are known as BALI drop-in sugars and are characterized by a high purity and very low concentrations of inhibitors, making them an ideal starting point for fermentations or chemical conversion to chemicals and building blocks. They can be blended with conventional 1G dextrose syrups (e.g. DE95 syrups) at any ratio and ultimately replace these, without loss of fermentation activity. The crude lignin stream may contain sugar if the pretreatment has been performed under acid conditions. These may then be fermented prior to further downstream processing of the lignin to lignin performance chemicals.
Following the enzymatic hydrolysis the resulting hydrolysates can be fermented in 30, 300 and 3000 L reactors in a state of the art multi-purpose fermentation facility located right next door to the BALI demo plant
Martin Lersch from Borregaard: commented, “The experimental work that led to the BALI process began in 2007. Eventually there was a need to scale up the process in order to continue with development. Construction of the BALI demonstration plant commenced in 2012 and was inaugurated in 2013. The demo plant was built specifically for the BALI process with a capacity to process 1-2 MT/day of feedstock. The feedstocks tested so far in the demo plant include Norway spruce (Picea abies), loblolly pine (Pinus taeda), bagasse (Saccharum spp.) and willow (Salix spp.). More than 800 MT of feedstock (wet basis) have been subjected to sulfite pretreatment and downstream processing. Additionally, more than 25 MT of spruce pulp (dry basis) have been subjected to enzymatic hydrolysis.
Category: Fuels
