Biofilm thickness variability investigated with a laser triangulation sensor

Area of Science:

• Environmental microbiology
• Biofilm engineering
• Sensor technology

Background:

• Measuring biofilm thickness and surface roughness is typically destructive and time-consuming.
• This limits in-situ research on biofilm development and function.
• Existing methods hinder real-time monitoring of biofilm parameters.

Purpose of the Study:

• To develop a fast and nondestructive method for measuring biofilm surface roughness and thickness.
• To investigate the morphological development of a dichloromethane (DCM)-degrading biofilm.
• To differentiate biofilms based on surface characteristics in a waste gas treatment system.

Main Methods:

• Development of a laser triangulation sensor (LTS) setup.
• Non-destructive monitoring of biofilm growth on a wetted-wall column.
• Analysis of biofilm morphology, including colony formation and surface area changes.
• Application of LTS in a laboratory trickling filter for DCM removal.

Main Results:

• The LTS enabled rapid, non-destructive measurement of biofilm parameters.
• Biofilm developed faster at the reactor entrance, with increased surface area by 23%.
• Distinct biofilm surface roughness variations were identified in a DCM-removing trickling filter.

Conclusions:

• The LTS is a valuable tool for studying biofilm morphology and development.
• Understanding biofilm surface characteristics is crucial for optimizing waste gas treatment processes.
• The developed method facilitates research on biofilm reaction-diffusion and hydrodynamics.