Standardised methodology - testing effluent samples for NATA labs

36 Pages

Author(s): Kalinda Watson, Stephen Wiedemann

Biogas yield is determined by the mass and characteristics of the volatile solids (VS) that flow into the system, however there are difficulties when it comes to measuring VS. These difficulties make it difficult to accurately predict methane gas potential in biogas systems, or to optimise these systems. This project aimed to determine the evaporation of volatile fatty acids (VFAs) in the VS and total solids (TS) analysis process, and use this to provide an alternative and more accurate testing methodology.

Benefit to industry:

• Optimising biogas systems through a more accurate effluent testing method

Key findings:

• The overall analysis cost for the new method is ~$130 per sample, making this a low cost solution.
• Current methods underestimate VS by 0-15%.
• An alternate VFAs testing method was more accurate.
• Recommend this method be used to assess VS in Australian biogas systems moving forward.
• Regular VS and VFA sampling should be conducted to assess temporal variations.