This study was conducted to evaluate the effect of loading frequency on treatment performance of faecal sludge (FS) with drying beds planted with Echinochloa pyramidalis. Beds were loaded at a constant total solids (TS) loading rate of 200 kg TS/m2*year, at a frequency of 1X, 2X or 3X per week. The FS was highly variable, with a range of 2,600–21,492 mg/L TS, which resulted in variable hydraulic loadings. Weekly monitoring was conducted 23 times over a period of nine months. Increased loading frequency resulted in increased plant growth with 211, 265 and 268 plants/m2, respectively, for the 1X, 2X and 3X, and the 2X and 3X loadings had 12–13% more liquid lost due to evapotranspiration versus percolation. Even with high removals that were resistant to variable hydraulic loadings, leachate had 883–5,228 mg/L TS, 49–727 mg/L total suspended solids and 92–1,853 mg/L chemical oxygen demand due to the high initial concentrations. Increased loading frequency resulted in greater nitrification, with 7–28, 18–43 and 28–51 mg/L NO3 for 1X, 2X and 3X, respectively. FS requires a longer storage time than three months for stabilization and pathogen reduction. These results provide valuable information for FS planted drying bed operation.

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