Environmental Engineering Reference
In-Depth Information
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symptom 3.
Vacuum pump stops.
Causal factors:
No power to drive motor; lack of seal water; broken
drive belt
Corrective action:
Reset heater, breaker, etc.; restart seal water
flow; replace drive belt.
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symptom 4.
Drum stops rotating.
Causal factor:
No power to drive motor
Corrective action:
Reset heater, breaker, etc.; restart.
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symptom 5.
Receiver is vibrating.
Causal factors:
Clogged filtrate pump; loose bolts and gasket around
inspection plate; worn ball check valve in filtrate pump; air leaks in
suction line; dirty drum face; missing seal strips
Corrective actions:
Clean pump; tighten bolts and gasket; replace
ball check; seal leaks; clean face with pressure hose; replace
missing seal strips.
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symptom 6.
Vat level is high.
Causal factors:
Improper chemical conditioning; feed rate too high;
drum speed too slow; clogged or off filtrate pump; plugged drain
line; vacuum pump stopped; missing seal strips
Corrective actions:
Change coagulant dosage; reduce feed rate;
increase drum speed; turn on or clean pump; clean drain line;
replace seal strips.
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symptom 7.
Vat level is low.
Causal factors:
Feed rate too low; vat drain valve open
Corrective actions:
Increase feed rate; close vat drain valve.
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symptom 8.
Vacuum pump is drawing high amperage.
Causal factors:
Clogged filtrate pump; improper chemical condition-
ing; high vat level; cooling water flow to vacuum pump too high
Corrective actions:
Clear pump clog; adjust coagulant dosage;
decrease cooling water flow rate.
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symptom 9.
Scale buildup occurring on vacuum pump seals.
Causal factor:
Hard, unstable water
Corrective action:
Add sequestering agent.
10.7.2.3 Process Control Calculation: Vacuum Filter Yield
Probably the most frequent calculation vacuum filter operators
have to make is determining filter yield. Example 10.27 illustrates how
this calculation is made.
