Effect of Ultrasound on Reaction Rates of Bioprocesses

摘要

In many cases, biological processes are more preferable than chemical processes. However, there is always the need for higher rates of biological reaction because they are often relatively slowly. The improvement of rates of chemical reaction by ultrasound (US) transduction in the reactors is well known. In contrast to this, ultrasound-assisted biochemical reactions are published only in few papers. One possible reason is that the negative effects such as inhibition or disruption have to be overcome. First results show that negative effects could be made positive if the ultrasound power input is far below the cavitation regime. An optimisation of bio-reactor design is necessary. Moreover, to ensure optimised rates of reaction the US-intensity must be focussed on a window range, which must be adapted to the type of biochemical reaction. The kinetic study shows that the rates of reaction could be enhanced twice for the aerobic fermentation of glucose as well as for the anaerobic de-nitrification process in wastewater treatment. This lead to significant reduction of reactor volume and investment costs.