In comparison with the solid retention of the catch basin with the small waste bucket and invert outlet, which was set at 100 %, the separation catch basin (SCB) had an improved performance of about 167 % compared to the catch basin with a silt trap (CBS), and by about 367 % compared to the catch basin with a large waste bucket and sump, and by about 420 % when compared to the catch basin with small waste bucket. This balance does not include the coarse organic material retained on the road surface by the grate in the first separation step.

In the case of the catch basin with a waste bucket, these particles remained in the bucket. In contrast, the catch basin with a silt trap discharged most of the solids directly into the storm sewer, hence contributing to the formation of solids in the sewer system.

The increased retention of solids in the case of the separation catch basin is the result of the funnel insert construction. The funnel prevents water turbulence and mobilisation of the solids that have already settled in the sump. On the other hand, finer mixtures of solids could increasingly settle, i.e. d50 = 0.43 mm, compared to d50 = 1.0 mm in the CBS and to 1.3 mm in the bucket of the CB with large waste bucket.
 

Help for presentation mode

Show / hide the Table of Contents

Go to previous page

Go to next page

Show additional information for the current page

Show this help

Useful browser keystrokes

Typically, your browser supports the following keystroke commands:

[Ctrl]+[+] Enlarge text fonts

[Ctrl]+[-] Downsize text fonts

[Ctrl]+[F] Find text in local page