Design Requirement of Activated Sludge Process

1. AERATION TANK

     A. Design criteria

      Sustained peak mass loading factor 1.15;    

      Design based on peak mass loading & cell mean resident time;

      Kinetic coefficient: Y = 0.6, k_d = 0.06 1/d for  q_c= 5 day

      MLSS 2,000 ~ 4,000 mg/l;

      Tank No > 3.

     B. Calculation and arrangement of Tank size, inlet, outlet and conduit

     C. Operation control

2. AERATION SYSTEM

     A. Design criteria

      Standard oxygen requirement for design of blower, diffuser and piping: C_s20 = 9.1 mg/l, a = 0.9, � = 0.85;

      Diffuser transfer efficiency, SOTE =10%;

      Safety factor = 2.0;

      Diffuser-Aerator: Discfuser and Swing Aerator (see manufacture menu);

      Airfilter and silencer: Series F64 and BMSI;

      Blower: Rotary Positive displacement (manufacturer menu), Number of blowers >3.

     B. Calculation and Arrangement of diffuser, piping system and blower

     Design based on SFL and peak over flowrate at different operation situation, R (return sludge rate);

      Check underflowrate and detention time of sludge solids;

      Clarifying detention time = 2 hr;

      Depth = claridying's + thickening's + sludge storage;

      Tank No. >3;

      Centrifugal pump for sludge recycling and wastage.

    B. Calculation and arrangement of tank size, inlet, outlet and pumping requirement

    C. Operation control

4. Hydraulic profile and sketch aeration tank and settling tank

5. Flowrates and influent quality: term project