Abstract:
The research was aimed to study on the cyanide removal efficiency by packed cage RBC system . The experiments were carried out in laboratory scale packed cage RBC system. The system was consisted of 43 Iitres cylindrical reactor and packed drum which has 40% of volume that submersed in wastewater. The media which was packed in drum was polyethylene square ring type. The total surface area of media was 12.67 m2. The rotary speed was 3 rpm. The synthetic wastewater was prepared at the BOD concentration of 800 mgL and potassium cyanide concentration (5, 10,15, 20, 25, 30 and 40 mg CNL) on the efficiency of packed cage RBC system. And also the effect of hydraulic retention time (8, 12 and 16 hours: 2.4, 1.6 and 1.2 gBOD,L-d) on the efficiency of the system with potassium cyanide containing wastewater. The results showed that the COD, BOD,, TKN and cyanide removal efficiencies were decreased with the increase of potassium cyanide concentration. The system showed the highest COD, BOD,, TKN and cyanide removal efficiency of 94.00*1.64, 94.75*0.85, 59.07*2.75 and 95.49M.56% respectively at the lowest cyanide concentration of 5 mg CNL In addition, the effluent ammonium, nitrite and nitrate were increased with the increase of potassium cyanide concentration similar to increase the potassium cyanide loading of the system. To study the effect of hydraulic retention time (HRT) of the system as 8, 12 and 16 hours (2.4, 1.6 and 1.2 gBOD,/L-d) the synthetic wastewater containing potassium cyanide was used. The results showed that the reinoval efficiency was increased with the increase of HRT in potassium cyanide containing synthetic wastewater. The highest COD; BOD,, TKN and cyanide removal efficiency of 89.89h0.49, 91.79h0.69, 62.2851.46 and 94.97h0.08 % respectively with potassium cyanide concentration of 30 mgCN/L containing synthetic wastewater was given with HRT of 12 hours (0.06 gCN/L-d). While, the highest COD, BOD, and TKN removal efficiency of 88.81h0.68, 92.84h0.67, 60.26h3.65 lltig 95.17h0.21 % respectively with potassium cyanide concentration of 40 mgCN/L containing synthetic wastewater was given with HRT of 16 hours (0.06 gCN/L-d). In addition, the effluent ammonium, nitrite and nitrate were decreased with the increase of BRT due to the increase of organic loading.