nbVSS - nonbiodegradable Volatile Suspended Solids
In the nomenclature of wasterwater engineering the nbVSS, stands for
nonbiodegradable Volatile Suspended Solids (nbVSS). The nbVSS
referes to the concentrations of nonbiodegradable organic material, among
wich the cell debris from endogenous respiration. (pages 581)
The nbVSS concentration is of great significance in proces design. The
effect of nbVSS concentration in the influent will be significant in proces
sludge production and aeration volume requirements. (page 704)
The nbVSS concentration resulting from cell debris is typically arelativly
small fraction of the VSS in a bioreactor used to treat municipal and some
industrial wastewaters. For typical untreated municipal wastewaters the
nbVSS concentration may be in the range from 60 to 100 mg/L, and following
primary treatment may range from 10 to 40 mg/L. (page 586)
The wastewater nonbiodegradable volatile suspended solids concentratie can
be estimeted from analyses for COD, sCOD, BOD, sBOD, and VSS concentration,
and by assuming a constant COD/VSS ratio for both biodegradable and
nonbiodegradable VSS:
Where:
| nbVSS = |
nonbiodegradable Volatile Suspended Solids |
[g/m3] or [mg/l] |
| BOD = |
Biological Oxygen Demand |
[g/m3] or [mg/l] |
| COD = |
Biological Oxygen Demand |
[g/m3] or [mg/l] |
| bpCOD = |
concentration of biodegradable
particulate COD |
[g/m3] or [mg/l] |
| pCOD = |
concentration of particulate COD |
[g/m3] or [mg/l] |
| sCOD = |
concentration of soluble COD in
activated-sludge effluent |
[g/m3] or [mg/l] |
source: Metcalf and Eddy
|
