2.2.3. Test Plant

2.2.3. Test Plant

Calculations - Test Plant 1

Water volume: 0.4 x 0.915 x 0.6  =  0.2196m3

Filter volume:

     BIO-BLOK® 100: 3.0 x 0.14 x 0.4 x 0.5  =  0.084m3 BIO-BLOK® 100

          2mm biofilm: 0.084 x 233  =  20m2          3mm biofilm: 0.084 x 299  =  25m2

     BIO-BLOK® 150 HD: 3 x 0.165 x 0.4 x 0.5  =  0.099m3 BIO-BLOK® 150 HD

          1mm biofilm: 0.099 x 268  =  27m2
          2mm biofilm: 0.099 x 387  =  38m2
          3mm biofilm: 0.099 x 507  =  50m2

A thickness of biofilm on BIO-BLOK® 100 is estimated at about 2mm and a thickness of biofilm on BIO-BLOK® 150 HD at 1mm. Based on this estimation, the following biological accessible area is attained: 20 + 27 = 47m2.

It is assumed that the BOD5 content in the inlet water is 400 mg/l and that the BOD5 content in the outlet water is about 20 mg/l corresponding to a reduction of about 95%.

A decomposition speed is estimated at about 13mg BOD5/m2 x day by 10oC.

Total biological area = 24 x Q (400 - 20) / 13 = 47m2 

     Q = 0.067 m3/h or 1.12 l/min

Residence time in the test plant:
0.2196 / 0.067 = 3.27 hours

Calculation of air volume:

An air need is estimated at 40m3 air per kg supplied COD/day. At the same time a BOD5/COD content of 1 : 2 is implied.

Total COD per day = 2 x 0.067 x 400 x 24 = 1286g COD/day

Total air volume: 40 x 1.286 = 51.3 m3/day corresponding to 2.14 m3 air/h

Final sedimentation tank:
Ø 40cm, cross-sectional area: 0.1248 m2

Hydraulic Surface Load (HSL): 0.067 / 0.1248 = 0.5 m/h < 5 m/h


Calculations - Test Plant 2

Water volume: 0.4 x 0.955 x 1.15  =  0.440m3

Filter volume:

    
BIO-BLOK® 100: 3.0 x 0.14 x 0.4 x 1.0  =  0.168m3 BIO-BLOK® 100

          2mm biofilm: 0.168 x 233  =  40m2
         
3mm biofilm: 0.168 x 299  =  50m2

BIO-BLOK® 150 HD: 3 x 0.165 x 0.4 x 1.0  =  0.198m3 BIO-BLOK® 150 HD

          1mm biofilm: 0.198 x 268  =  53m2
         
2mm biofilm: 0.198 x 387  =  76m2
          3mm biofilm: 0.198 x 507  =  100m2

A thickness of biofilm on BIO-BLOK® 100 is estimated at about 2mm and a thickness of biofilm on BIO-BLOK® 150 HD at 1mm. Based on this estimation, the following biological accessible area is attained: 40 + 53 = 93m2

It is assumed that the BOD5 content in the inlet water is 400 mg/l and that the BOD5 content in the outlet water is about 20 mg/l corresponding to a reduction of about 95%.

A decomposition speed is estimated at about 13mg BOD5/m2 x day by 10oC.

Total biological area = 24 x Q (400 - 20) / 13 = 93m2

     Q = 0.133 m3/h or 2.22 l/min

Residence time in the test plant:
0.440 / 0.133 = 3.3 hours

Calculation of air volume:

An air need is estimated at 40m3 air per kg supplied COD/day. At the same time a BOD5/COD content of 1 : 2 is implied.

Total COD per day = 2 x 400 x 0.133 x 24 = 2,554g COD/day

Total air volume: 40 x 2.554 = 102 m3/day corresponding to a minimum of 4.25 m3 air/h

A blower with a capacity of 5 - 10 m3/h is chosen.


Final sedimentation tank: Ø 40cm, cross-sectional area: 0.1248 m2

Hydraulic Surface Load (HSL): 0.133 / 0.1248 = 1.07 m/h < 5 m/h