6.3 Treatment Performance

In 2019, a comprehensive assessment of the Rohingya refugee camp was conducted, focusing on biogas production and treatment performance, specifically regarding COD removal rates. The study analysed 21 digesters within the camps.

The analysis results are presented through a series of boxplots, depicting information about the COD influent, removal rates, and effluent. The interquartile range (IQR) is shown in these boxplots as a bar, indicating the most common COD value ranges observed.

The COD influent values ranged from 20,000 to 65,000 mg/L, reflecting the varying levels of contamination in the processed waste. The removal rates achieved by the digesters ranged from 69% to 91%, indicating a significant reduction in COD levels during treatment. This demonstrated the effectiveness of the digesters in removing contaminants from the influent.

However, despite the favourable removal rates, the COD levels in the effluent still ranged from 2,900 to 10,400 mg/L. While these values showed a considerable improvement compared to the influent, they indicated that additional post-treatment measures are still required if the effluent is not infiltrating.