Abstract
BACKGROUND: Poultry slaughterhouse wastewater has a complex composition that is very harmful to health and the environment. A two-stage system is applied to treat wastewater, consisting of an anaerobic filter (AF) combined with constructed wetland (CW).
AIM: Experiments carried out under mesophilic conditions aim to evaluate the performance of a biological treatment combining AF and CW on three media filters.
METHODS: Observations were made for 15 consecutive days on chemical oxygen demand (COD), BOD5, TSS, pH, and fat oils and grease FOG (35.5 mg/L). The treatment system is operated with a sewage loading of 14 m3 s-1 and an RTH of 18.2 h.
RESULTS: The results showed that before processing, the average values of COD (2881.4 mg/L), BOD5 (967 mg/L), TSS (860.3 mg/L), pH (6.7), and FOG (35, 5 mg/L). The greater efficiency was obtained using gravel media, BOD5 (88.9%), COD (92.9%), TSS (93.4%), and FOG (87.3%). Optimal treatment conditions in this system were found for AF with gravel media, operating at hydraulic retention time = 4.2 h, out of a total of 18.2 h. The IB value increased from 0.3 to >0.5, indicating the combined AF and CW method is suitable for treating wastewater from poultry slaughterhouses.
CONCLUSIONS: The combination of the AF method and CW is well applied to the wastewater treatment of poultry slaughterhouses, and parameters values have complied with the applicable regulations. Nevertheless, the removal of oil and grease is highly recommended in pre-treatment to inhibit the anaerobic process.
Publisher
Scientific Foundation SPIROSKI