ProMinent ProMix C, Operating Instructions Manual

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Pr o Minent ProMix
‘S & C’ Polymer Feeder
ProMix Series S&C User Manual
Appendix C
– Polymer Sizing / Dosage
The ProMix S & C Polymer Pump switch on the controller door enables the user to select either
LOCAL or REMOTE operation.
In ‘LOCAL’, the polymer pump speed is selectable from 0 - 100%
using the controller keypad.
In ‘REMOTE’, the polymer pump speed is controlled by a remote 4-20
mA signal representing 0
– 100%.
The desired polymer dosage must be considered prior to selecting the ProMix S/C model and pump
speed. Typically the user will know how much polymer is required. This information is from jar
tests or from prior experience. Otherwise the dosage can be derived from an initial manual
calculation which must be adjusted based upon actual operation.
Below are typical guidelines to estimate polymer feed dosage:
1. For a Clarifier / Filter application:
A = MGD Plant Flow
B = ppm active polymer
C = desired solution concentration (%)
(A*B)/24 = GPH active polymer
GPH active polymer/C = Required dilution range
2. For a Sludge Dewatering application:
User must have the following information to estimate GPH neat polymer:
A = GPM sludge
B = % solids (concentration)
C = lbs polymer per dry ton
D = percent active polymer
E = desired solution concentration (%)
(((A*8.34)*B)*60)/2000 = Tons/Hr dry sludge
(((Tons/Hr dry sludge*C)/8.34)/D)/E = Required dilution range
The polymer concentration from the ProMix S/C Polymer feeder is based upon the neat polymer
pump rate divided by the total water flow through the primary and secondary rotameters. For
example, if the neat polymer feed rate is 1.5 gph and the flow through the primary rotameter is 15
gpm and the flow through the secondary rotameter is 10 gpm then the polymer concentration is:
((1.5 gph / 60) / (15 gpm + 10 gpm)) = 0.001 = 0.1%
Further post dilution is possible with equipment by others.