Characterization and Anaerobic Biodegradation of Single House Wastewater

Anaerobic biodegradation and characterization of wastewater produced at household level in rural areas in Jordan were considered in this study in order to investigate the possibility of applying house onsite low cost treatment systems. Results showed that the total chemical oxygen demand (CODtot) was 1.8 times higher during summer than during winter. The average CODtot during summer and winter amounted to 2982 mg/l and 1683 mg/l, respectively. The suspended fraction of the COD represents 41% and 38% of CODtot for summer and winter, respectively. Maximum anaerobic biodegradability of the wastewater was found to be 43% (COD basis) for unseeded samples and 59% for seeded samples after 159 days of digestion at 25ºC. Hydrolysis rate constant for the seeded samples was calculated to be 0.006 d-1 (R2= 0.877). Low biodegradability measured for the wastewater was mainly attributed to excessive use of detergents and disinfectants. Accordingly, household habits should be changed before effective biological anaerobic treatment can be considered.