https://phys.org/news/2018-06-self-sustaining-loop-chemical-reactions-revolutionize.html

The reactions reduce environmental waste, are self-sustaining and produce higher qualities of the end product.

Enzymes in flow, as used as a series of 'columns' packed with immobilised enzymes and a carrier solution, flows the reagents in and the products out with much faster reaction rates that in normal batch reactions.