Development of granular sludge on cane sugar mill waste treatment using a pilot scale UASB reactor

A UASB pilot plant of 2.83 m 3 capacity was operated for 526 days to assess the treatability of cane sugar mill wastewater, at an HRT of 5.5 h, and average organic loading rate of 13 kg COD/m 3 . d, giving a COD reduction of 75-80 percent. The average methane gas recovery was 0.22 m 3 CH 4 /kg COD removed at an average temperature of 34°C. The biomass grew in the form of granules with excellent settling properties and a high methanogenic activity of 0.56 kg COD-CH 4 /kg VSS.d.