Clarifier Surface, Weir, and Solids Loading

Whether a clarifier is inside its surface, weir, and solids loading limits.

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Example

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Details, formula, and sources

Surface overflow rate = flow/area (gpd/ft^2), weir overflow = flow/weir (gpd/ft), solids loading = flow x MLSS x 8.34 / area. 1 MGD, 40 ft dia (1257 ft^2), MLSS 2500 -> SOR 796, weir 7,958, solids 16.6; double the flow and SOR passes the ~1000 limit (floc carryover). The state design criteria govern.

SOR = flow x 1e6 / area (gpd/ft^2); weir = flow x 1e6 / weir_len (gpd/ft); solids = flow x MLSS x 8.34 / area (lb/ft^2/day).

Clarifier surface, weir, and solids loading rates, standard wastewater-operations practice (Ten States Standards / Metcalf & Eddy), by name.

The overflow-rate and solids-loading relations are standard published wastewater results; the state design criteria govern the limits.

Estimate. Operator of record and primacy agency govern.

Field names used by the API: flow_mgd, surface_ft2, weir_len_ft, mlss_mgl, sor_gpd_ft2, weir_gpd_ft, solids_lb_ft2_day

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