GORMAN-RUPP VG3B3-B, Инструкция по установке, эксплуатации и обслуживанию

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Aqua UltraFiltration™ Membrane System Control Strategy
ID #107150D Page 5 of 37 Revision: 1
Augusta Correctional Center WWTP
© 2013 Aqua-Aerobic Systems, Inc.
During filtration, the Permeate Valve (EV4X02) is open and the Backwash Pumps are off.
During production mode, filtered water is prevented from flowing backwards through the
pumps by a Train Backwash Valve (EV4X03).
When a backwash is initiated, the permeate valve closes, the module backwash valve opens,
and two of the Backwash Pumps pulls water from the Permeate Tank (T6001) in order to
pressurize the membrane (from outside-in). The PLC uses the Permeate Tank level
transducer (LT6001) to check the level status in the Permeate Tank to confirm adequate
water is available to complete the backwash.
The Backwash pumps are controlled with VFDs, as each operates at different flow rates
depending upon the type of backwash. For example, a typical backwash will operate two
pumps at a total flux of 230 lmh, whereas a chemically-enhanced backwash (CEB) will use
only one pump at a much lower flux of 130 lmh. The PLC monitors the Backwash Flow
meter (FT6001) and adjusts the speed of the operating pump through the VFD.
e. Chemical Feed Pumps (provided by others)
On occasion, it will be necessary to chemically clean the membranes by use of the
chemically enhanced backwash (CEB) function. The operational strategy for the membranes
uses three (3) CEB modes detailed later in this document:
1. CEB1: A chemically enhanced backwash which uses base (NaOH) followed by
soaking, rinsing and the subsequent addition of hydrochloric acid (HCl) to remove
any precipitates formed by the addition of base.
2. CEB2: A chemically enhanced backwash which HCl to remove inorganic fouling.
3. CEB3: A chemically enhanced backwash which sodium hypochlorite (NaOCl) to
disinfect the modules.
For this project, three chemical feed pumps are provided by others to inject chemicals into
the permeate piping during the three CEB modes. The pumps include:
1. Acid Pump – This pump is employed after base during a CEB1, and to control
inorganic fouling as part of a CEB2 mode.
2.
Base Pump – This pump is used to remove organic fouling using base (NaOH),
which is injected into the permeate line during a CEB1 mode.
3. Chlorine Pump – This pump is used to disinfect the membranes using NaOCl,
which is injected into the permeate line during a CEB3 mode.
The Operator shall determine the proper dosage rate and make the adjustments at the
pump via the calibration. The respective processing times are placed into the HMI and
the PLC shall operate the pumps according to the program during the automatic CEB.