Sludge Volume Index (SVI)
SVI = SV30 * 1000 / MLSS in mL/g, with operator-typical operational bands (typical / pin floc / filamentous / bulking). Companion to the srt-fm-ratio tile.
Formula and source
SVI (mL/g) = (SV30 mL/L * 1000) / MLSS mg/L. Bands: < 80 pin-floc / under-aerated; 80-150 typical CAS; 150-200 filamentous developing; > 200 bulking.
USEPA Wastewater Operator Training (public domain); WEF Manual of Practice No. 11 by name.
Audience
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Posture
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