Environmental Engineering Reference
In-Depth Information
8.13.1.6 Alkalinity
Alkalinity is essential to biological activity. Nitrification requires
7.3-mg/L alkalinity per mg/L total Kjeldahl nitrogen.
8.13.1.7 BOD
5
Testing showing an increase in BOD
5
indicates increased organic
loading; a decrease in BOD
5
indicates decreased organic loading.
8.13.1.8 Total Suspended Solids
An increase in total suspended solids (TSS) indicates an increase
in organic loading; a decrease in TSS indicates a decrease in organic
loading.
8.13.1.9 Total Kjeldahl Nitrogen
Total Kjeldahl nitrogen (TKN) determination is required to monitor
process nitrification status and to determine alkalinity requirements.
8.13.1.10 Ammonia Nitrogen
Determination of ammonia nitrogen is required to monitor process
nitrification status.
8.13.1.11 Metals
Metal contents are measured to determine toxicity levels.
8.13.2 aeration Tank
8.13.2.1 pH
Normal pH range in the aeration tank is 6.5 to 9.0. Decreases in pH
indicate the presence of process sidestreams or that insufficient alka-
linity is available.
8.13.2.2 Dissolved Oxygen
The normal range of DO in an aeration tank is 1 to 3 mg/L. Dissolved
oxygen level decreases may indicate increased activity, increased tem-
perature, increased organic loading, or decreased MLSS/MLVSS. An
increase in dissolved oxygen could be indicative of decreased activity,
decreased temperature, decreased organic loading, increased MLSS/
MLVSS, or influent toxicity.