It was studied the biogas production through the treatment of the wet processing coffee wastewaters (ARC) in an anaerobic treatment system in laboratorial scale. The system used was composed by one acidification and equalization tank (TAE), one anaerobic upflow sludge blanket reactor (UASB), one facultative aerated pond, one equalization tank and one gas tank. The treatment was carried out for 190 days and the pH was controlled for some periods by adding NaOH inside of the TAE or in the UASB. In the UASB reactor the maximum and minimum values obtained in the inlet were 235 to 7064 mg.L-1 for COD; 200 to 3913 mg.L-1 for BOD5, 500 to 11.153 mg.L-1 for TVS and 4,57 to 7,75 for pH. In the outlet of the UASB, the values were 39 to 2333 mg.L-1 for COD; 15 to 1300 mg.L-1 for BOD5, 272 to 2749 mg.L-1 for TVS and 6,16 to 7,93 for pH. The minimum and maximum values of the inlet flow were 0,18 to 1,56 L.h-1. The biogas presented a theoretical production of the 0,545 to 0,602 m³.Kg-1BOD5 and methane percentage from 48,60 to 68,14%.
Coffee; wastewaters; anaerobic treatment; methane
