NS2 SYSTEM DESCRIPTION for water treatment plant

FOR CONSTRUCTION

1
0
Rev
Owner

16.10.2019

J.H.SEOK

Y.H.PARK

S.K.LEE

25.07.2019

J.H.SEOK

Y.H.PARK

S.K.LEE

Date

Prepared

Checked

Approved

FOR CONSTRUCTION
FOR CONSTRUCTION
Details of Revision

Owner’s Engineer

Contractor

DOOSAN HEAVY INDUSTRIES & CONSTRUCTION
Sub-Supplier

SAFBON WATER TECHNOLOGY
Project

NGHI SON 2 BOT THERMAL POWER PLANT
(2 x 600MW)
Title

[water treatment plant]_SYSTEM DESCRIPTION

Document No.

Rev.

NS2-XS00-P0GCF-120001

Page-No.

1

29


[water treatment plant]_SYSTEM DESCRIPTION
NS2-XS00-P0GCF-120001

RECORD OF REVISION
Rev.

Date

Page Affected

Description of Revision

0

25.07.2019

16

For Construction

1

16.10.2019

For Construction

Rev.1

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[water treatment plant]_SYSTEM DESCRIPTION
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1.

INTRODUCTION................................................................................................................ 4

2.

SYSTEM / COMPONENT DESCRIPTION ..................................................................... 4

2.1.

GENERAL REQUIREMENT ............................................................................................ 4

2.2.

DESIGN AND FLOW PATH DESCRIPTION ................................................................. 4

3.

MAJOR EQUIPMENT DESCRIPTION........................................................................... 6

3.1.

PRETREATMENT SYSTEM ............................................................................................ 6

3.1.1.

COAGULANT DOSING SYSTEM ................................................................................... 7

3.1.2.

POLYMER (COAGULANT AID) DOSING SYSTEM ................................................... 7

3.1.3.

SODIUM HYPOCHLORITE DOSING SYSTEM ........................................................... 7

3.1.4.

ACID DOSING SYSTEM ................................................................................................... 7

3.1.5.

CLARIFIED WATER POND ............................................................................................. 7

3.1.6.

ULTRA FILTRATION SYSTEM ...................................................................................... 7

3.1.7.

UF CLEANING PUMPS ..................................................................................................... 8

3.1.8.

UF AIR BLOWERS ............................................................................................................. 8

3.1.9.

FILTERED WATER POND ............................................................................................... 8

3.2.

SWRO SYSTEM .................................................................................................................. 9

3.2.1.

SODIUM BISULFITE DOSING SYSTEM ....................................................................... 9

3.2.2.

ANTISCALANT DOSING SYSTEM .............................................................................. 10

3.2.3.

CARTRIDGE FILTERS FOR SWRO ............................................................................ 10

3.2.4.

SWRO HIGH PRESSURE (HP) PUMPS WITH VFD .................................................. 10

3.2.5.

SWRO TRAINS ................................................................................................................. 11

3.2.6.

ENERGY RECOVERY DEVICE WITH BOOSTER PUMPS WITH VFD ............... 11

3.2.7.

SWRO FLUSHING PUMPS ............................................................................................. 11

3.2.8.

RO CIP SYSTEM .............................................................................................................. 12

3.3.

BWRO SYSTEM ............................................................................................................... 12

3.3.1.

BWRO HIGH PRESSURE PUMPS WITH VFD ........................................................... 13

3.3.2.

BWRO TRAINS ................................................................................................................. 13

3.3.3.

DEGASIFIER ..................................................................................................................... 14

3.4.

MIXED BED POLISHER UNITS .................................................................................... 14

3.4.1.

MBP FEED PUMPS .......................................................................................................... 14

3.4.2.

MIXED BED POLISHER UNITS .................................................................................... 14

3.4.3.

REGENERATION SYSTEM ........................................................................................... 14

3.5.

POTABLE WATER SYSTEM ......................................................................................... 15

3.5.1.

ACTIVATED CARBON FILTER VESSELS ................................................................. 15

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3.5.2.

SODIUM HYPOCHLORITE DOSING SYSTEM ......................................................... 15

3.6.

CHEMICAL STORAGE................................................................................................... 15

3.6.1.

ACID STORAGE, UNLOADING / TRANSFER SYSTEM .......................................... 15

3.6.2.

CAUSTIC STORAGE, UNLOADING / TRANSFER SYSTEM .................................. 15

3.6.3.
ANTISCALANT, COAGULANT, NAOCL STORAGE, UNLOADING / TRANSFER
SYSTEM 16
3.6.4.

SBS, COAGULANT AID STORAGE, UNLOADING / TRANSFER SYSTEM ......... 16

3.7.

FINAL TREATMENT OF WASTE WATER FROM WTP ......................................... 16

3.7.1.

NEUTRALIZATION CHEMICAL WASTE WATER .................................................. 16

3.7.2.

DISPOSAL OF SEA WATER WASTE ........................................................................... 16

4.

OPERATION ..................................................................................................................... 17

4.1.

SYSTEM OPERATION .................................................................................................... 17

4.1.1.

LAMELLA CLARIFIER .................................................................................................. 17

4.1.2.

ULTRA FILTRATION (UF) SYSTEM ........................................................................... 18

4.1.3.

SWRO UNITS .................................................................................................................... 20

4.1.4.

BWRO UNITS .................................................................................................................... 21

4.1.5.

MIXED BED POLISHER UNITS .................................................................................... 21

4.1.6.

POTABLE WATER SYSTEM ......................................................................................... 23

5.

DESCRIPTION OF CHEMICAL STORAGE & FILLING ......................................... 24

6.

INSTRUMENT AND CONTROLS ................................................................................. 24

6.1.

INSTRUMENTS ................................................................................................................ 24

6.2.

CONTROL ......................................................................................................................... 25

7.

CODE AND STANDARD ................................................................................................. 25

8.

REFERENCE ..................................................................................................................... 25

APPENDIX. A ...................................................................................................................................... 26

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1.

INTRODUCTION
This document provides the system description for the Water Treatment System for NGHI SON
2 Thermal Power Plant.
Raw sea water from CW pump is directly fed to the pre-treatment system and seawater must be
treated by Lamella Clarifier, Ultra Filtration (UF), and Sea water Reverse Osmosis (SWRO)
process as a source for the service water required.
The service water shall be transfer to Demineralized Water Treatment System to make
demineralized water which is consist of Brackish Water Reverse Osmosis (BWRO), Degasifier
and Mixed Bed Polisher.

2.

SYSTEM / COMPONENT DESCRIPTION

2.1.

General Requirement
The water treatment system plant is designed for the production of service water, potable water,
and demineralized water and consist of the following major equipment.
•

•

•

•
2.2.

Pretreatment system and associated chemicals: Lamella Clarification system, Ultra
Filtration (UF) system, coagulation and flocculant aid chemcial feed systems and
sludge treatment system.
RO system and associated chemicals which consist of SWRO trains, antiscalant
chemical feed systme, sodium bisulfite chemical feed system, Energy Recovery
Device (ERD) with booster pumps, SWRO permeate tank,
Demineralzied water system consisting of BWRO trains, a degasifier with blowers,
mixed bed polisher (MBP) trains, caustic and acid chemical regeneration feed
systems,
Potable water system consisting of activated carbon filters and chlorination.

Design and Flow Path description
Raw water passes through a static mixer, coagulation tank, flocculation tank, a lamella clarifier,
and finally is collected into clarified water pond.
Coagulant – ferric chloride (FeCl3) and sodium hypochlorite (NaOCl) are dosed into coagulant
tank directly and hydrochloric acid (HCl) is dosed into the static mixer located on raw water feed
common line. The static mixer ensures proper mixing of the acid before acid treated raw water
reaches the clarifier. An agitator is installed in the coagulation tank to mix the chemicals

rigorously.
The coagulation tank effluent overflows into the flocculation chamber which is equipped with an
agitator for slow & gentle mixing. In the flocculation tank, coagulant aid (polymer) is slowly
mixed with coagulated water to agglomerate smaller flocs formed in the coagulation tank into
larger one. The agglomeration of flocs or the creation of larger flocs will make it easier for
suspended solids to settle in the clarifier downstream.

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Dosing rates for both coagulant and coagulant aid (polymer) is determined at the site based on jar
tests and will be adjusted seasonally to account for changing water quality.
The chemically pretreated water flows through a basin with inclined (Lamella) plates where the
separation of solids occurs. Water flows upward through the inclined plates while solids slide
downward through the plates. The accumulated sludge at the bottom of clarifier will be pumped
to thickener by sludge disposal pump and will be further treated by filter press.
The clarified water quality to be;
• Turbidity ≤ 4 NTU
The clarified water (Turbidity≤4 NTU) is collected in a clarified water pond where it is pumped
to the UF unit for further filtration and solids removal. The filtrate (Turbidity≤0.1 NTU,
SDI≤3) from the UF is directed to the filtered water pond. UF cleaning water source for the
UF will be filtered water stored in the same tank. Air scour is employed to reduce the cleaning
wastewater and extend the service run.
The UF filtrate quality to be;
• Turbidity ≤ 0.1 NTU

• SDI ≤ 3
For the SWRO system, The SWRO feedwater is injected with sodium bisulfite for dechlorination
of SWRO feed water and ensure that no residual chlorine is present prior to entering the SWRO
as well as antiscalant is added as a safety factor for controlling scaling potential of all other ions.
The SWRO permeate quality to be;
• pH : 7.5 – 8.5 (after NaOH injection)
• Silica < 10 ppm
• TDS < 300 ppm
• Chloride < 175 ppm
The SWRO permeate is routed to plant & fire water storage tank as a source of service water
required. SWRO permeate is also routed to SWRO permeate tank for demineralized system
which consists of BWRO and MBP for boiler make up water.
The BWRO permeate quality to be,
• TDS ≤ 10 ppm (Max)
• Silica < 0.1 ppm
Permeate from the BWRO trains is routed to a permeate header which supplies water directly to
the Mixed Bed Polishers after passing through degasifier and BWRO brine is returning to SWRO
Feed. The Mixed Bed Polishers exchange the remaining anions and cations and CO2 in the RO
permeate producing ultrapure water to the Demineralized Water Storage Tank.

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The produced Demineralized water qualtity to be,
• Conductivity at 25C < 0.1 àS/cm

ã Total Silica as SiO2 ≤ 0.01 ppm
The mixed bed polisher resin is regenerated on a weekly (168 hr) basis, using acid and caustic.
The regenerated wastewater flows to chemical wastewater pond which is combined with UF
cleaning chemical waste. The combined chemical wastewater is transferred to Waste Water Plant.
The potable water system will take service water by potable water pumps from the plant & fire
water storage tank passing through a set of activated carbon filters to remove mainly organics.
The filter effluent is treated with sodium hypochlorite, to ensure that a residual chlorine remains
in the potable water tank. Typically, the system works based on the level in the potable water
tank. When there is a call for water, the activated filter is on, and when tank is full, the service
inlet valve to the activated carbon filter closes. On a periodic basis the activated carbon filter is
backwashed from plant & fire water storage tank and the wastewater generated is directed to the
chemical waste water pond.
3.

Major Equipment Description
Here is a description of the major equipment in the three major sections of the plant:
Pretreatment, SWRO, BWRO, and Mixed Bed Polishers.

3.1.

Pretreatment System
The Raw water pretreatment system comprises of following major equipment:
• 2 x 50% Coagulation Tank
• 2 x 50% Flocculation Tank
• 2 x 50% Lamella Clarifier System
• 1 x 100% Coagulant Dosing System
• 1 x 100% Polymer Dosing System
• 1 x 100% Sodium Hypochlorite Dosing System
• 1 x 100% Acid Dosing System
• 2 x 100% Sludge Disposal pumps

• 1 x 100% Thickener
• 2 x 100% Thickened Sludge Transfer pumps
• 1 x 100% Filter press
• 1 x 100% Clarified Water Pond
• 3 x 50% UF Feed Pumps
• 3 x 50% Auto Strainers
• 3 x 50% Ultra Filtration Trains
• 2 x 100% UF Air Blowers
• 2 x 100% UF Cleaning Pumps

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• 1 x 100% Filtered Water Pond
3.1.1.

Coagulant Dosing System
The coagulant is dosed into the coagulation tank and the coagulant dosing system consists of
following equipment:
• 2 x 100% Dosing Tanks
• 3 x 50% Dosing Pumps
It is expected the coagulant to be used is 38% ferric chloride solution which will be delivered to
the site and stored in the coagulant dosing tank and dosed into the feed water as per the dosing
rate that is established after conducting jar tests at site.

3.1.2.

Polymer (Coagulant Aid) Dosing System
The polymer is dosed into the flocculation tank as a coagulant aid. The Polymer Dosing System
comprises of the following equipment:
• 1 x 100% Polymer Auto Dissolving Unit
• 3 x 50% Dosing Pumps

3.1.3.

Sodium Hypochlorite Dosing System
Sodium hypochlorite will be dosed to maintain residual chlorine in the raw water. Sodium
hypochlorite dosing system comprises of the following equipment:
• 1 x 100% Dosing Tank
• 3 x 50% Dosing Pumps

3.1.4.

Acid Dosing System
Acid (HCl) solution will be dosed to decrease pH of the raw sea water. The acid flows by transfer
pumps from the acid storage tank which is a vertical 22 m³ tank used to supply acid for the entire
plant including acid for mixed bed regeneration and UF cleaning.
• 2 x 100% Dosing Tanks
• 2 x 100% Dosing Pumps

3.1.5.

Clarified Water Pond
The Clarified Water Pond (above ground) collects Clarified water from the Lamella Clarifier and
provide feed water connecting to UF feed pump. This pond is built of concrete and painted

internally. This Clarified Water Pond is provided with Level Transmitter.

3.1.6.

Ultra Filtration System

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Ultrafiltration (UF) is a process that filters particles on the basis of size. In membrane separations,
UF is typically used to separate or remove relatively large particles, such as microbes, bacteria,
and macromolecules with molecular weights greater than approximately 300,000 Daltons or sizes
greater than approximately 0.08 μm.

The primary objective of the UF membrane filtration system is to treat feed water high in
suspended solids to a quality acceptable for use as RO feed water. The UF membrane filtration
system consists of membrane modules installed in a skid assembly for space savings and ease of
operation. The membrane fibers are constructed of polyvinylidene difluoride (PVDF), which
provides good chemical and mechanical stability and capacity.
Clarified sea water is pumped through the UF filters by the UF Feed Pumps. In order to protect
the UF membrane fibers from damage by large debris and to prevent the growth of crustaceans,
raw seawater is pre-screened with strainers with 120 μm or smaller pore size. This pre-screened
water is then directly fed to the UF membrane skids.
The UF membrane system operation consists of filtration, flushing, air scouring, Maintenance
Cleans (MC), Recovery Cleans (RC), and Membrane Integrity Test (MIT). During filtration, feed

water is pressurized on the outside of the membrane fiber and forced into the inner lumen,
outside-in configuration.
UF has two flushing steps in control. One is feed flushing and the other filtrate flusing. Feed
flushing will be conducted by UF feed pump and filtrate flushing will be done by the cleaning
pumps. Cleaning water is the filtered seawater supplied from the filtered water pond and thus, all
cleaning waste water will be dumped to the seawater waste pond containing other seawater waste
and transferring to outfall.
3.1.7.

UF Cleaning Pumps
The cleaning pumps are provided to carry out cleaning operation of the UF membrane. Hydraulic
cleaning and maintenance cleaning are performed with chemical using UF cleaning pumps,
sodium hypochlorite dosing pumps, and hydrochloric acid dosing pumps. The cleaning initiation
is automatically triggered by the PLC based on timer (once every 24 hours).

3.1.8.

UF Air Blowers
The air scouring blowers are provided for the air scour of the UF membrane. The UF membrane
modules contain air manifolds and houseing on the bottom of each module to deliver air from the
UF air blowers. This air provides shear to the membrance surface, dislodging debris, which is
then flushed from the system.

3.1.9.

Filtered Water Pond

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The Filtered Water Pond (above ground) collects filtered water from the UF trains and provide in
return the water required for cleaning of the trains. This pond is built of concrete and painted
internally.
This Filtered Water Pond is provided with Level Transmitter. The outlet header of the UF trains
is provided with a turbidity analyzer to indicate the quality of water going into the filtered water
pond.
3.2.

SWRO System
The RO System for service water production comprises of following major equipment:
• 4 x 33% SWRO Feed Pumps
• 1 x 100% Sodium Bisulfite Dosing System
• 1 x 100% Antiscalant Dosing System
• 4 x 33% Cartridge Filters for SWRO
• 3 x 33% SWRO High Pressure (HP) Pump equipped with VFD
• 3 x 33% SWRO Trains
• 3 x 33% Energy Recovery Device (ERD) with booster pump with VFD
• 1 x 100% SWRO CIP System
• 2 x 100% SWRO Flushing pumps
• 1 x 100% SWRO Permeate tank
Water supplied to the SWRO trains is at high pressure and is monitored whether enough suction
pressure is provided for the SWRO high pressure (HP) pumps. On the same line, the followings
shall be installed:
• Pressure transmitter at both suction and discharge of HP pumps
• On/Off feed isolation valve to isolate all three trains

• Static mixer for antiscalant and sodium bisulfite
• On/Off dump valve to divert feed in case of ORP alarm which may indicate presence of
chlorine residual in the feed water to the SWRO trains

3.2.1.

Sodium Bisulfite Dosing System
RO membranes cannot tolerate the presence of residual chlorine, therefore a de-chlorination
chemical is used whenever residual chlorine is present in the feed water to the RO. Sodium
metabisulfite in the powder form is used as the de-chlorinating agent. When sodium metabisulfite
is mixed with water, it transforms into sodium bisulfite solution (SBS). As the dechlorination
reaction is very rapid, it is recommended to dose SBS at the upstream of RO Cartridge Filters.
SBS Dosing System comprises of the following equipment:
• 2 x 100% Dosing Tanks
• 2 x 100% Dosing Pumps

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The preparation of chemical solution will be done manually. If there is a presence of any residual
chlorine, a feed dump valve is provided after the cartridge filters on the RO feed water line to
divert the water to seawater waste pond. The residual chlorine is detected by two redundant set of
instrumentation: the ORP monitor and the chlorine residual monitor.
3.2.2.

Antiscalant Dosing System
Antiscalant is dosed to prevent membranes from scaling due to solubility limit. The antiscalant
poison the seeds of the nuclei that begin forming as the concentration of salts begin to exceed
their solubility limit. This usually occurs in the last stages of the RO and in the last membranes
where concentration of salts, especially, calcium carbonate, reaches four to five times their
concentration in the feed depending on the operating recovery. Antiscalant dosing system
comprises of the following equipment:
• 2 x 100% Dosing Pumps
• 2 x 100% Dosing Tanks

3.2.3.

Cartridge Filters for SWRO
In order to protect the SWRO membranes from small particulate matters, cartridge filters are
provided. Cartridge filters are the last filtration devices to protect the SWRO membranes from
small particulates and suspended and non-suspended solids.
4 x 33% capacity Cartridge Filter is provided in this plant, rated at 5 µm nominal particle size.
These Cartridge Filters are provided with suitable vent and drain valves that are manually
operated.
The Cartridge Filters are provided with a differential pressure transmitter across the inlet & outlet.
The plant should adopt a policy to replace the cartridges at regular interval (i.e., every two to four
weeks). However, if the differential pressure transmitter reaches the “high alarm setpoint” before
that time, the cartridges should be replaced.

3.2.4.

SWRO High Pressure (HP) Pumps with VFD
The SWRO high pressure pump provides the reverse osmosis pressure required to produce
required permeate water quantity and quality as projected by the RO computer projection.
Each SWRO train is supplied with a RO HP Pump sized adequately for the duty. VFDs will be

provided for the high pressure pumps of SWRO to ensure control of flow and pressure to the
SWRO membrane. The PLC will be programmed to operate the pumps to maintain constant
permeate flow regardless of the feed water temperature or membrane age. The SWRO HP pump
will not be located on the RO frame or Trains, and VFD will be located in the MCC.

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3.2.5.

SWRO Trains
The reverse osmosis trains employ thin film composite (TFC) membranes in a single-stage array
to produce the requisite permeate flow. The SWRO Membrane assembly for each train will have
a 36 pressure vessels. Each pressure vessel will contain 7 membrane elements. The entire RO
train is stacked in frame to facilitate installation, commissioning, operation and maintenance.
The train comprises of feed headers, permeate header and reject header. The concentrate control
valve on the SWRO train is controlled by its own flow loop to maintain constant recovery. This
control loop along with the VFD controlled pump will ensure that system recovery is maintained
at 45%.
SWRO train is provided with pressure transmitters at the membrane feed, total concentrate and
total permeate headers. The differential pressure between feed and concentrate will be
continuously calculated by PLC to provide an alarm to indicate when the membranes become due
for cleaning.
Flow indicating transmitters are provided at the permeate lines. The flow monitoring of permeate
will provide an indication.

A conductivity analyzer will be provided at the each train permeate line. The analyzer will
provide indication of the conductivity of the produced water. A sample valve will be provided at
each permeate line to detect if there is malfunction in any membrane in case of sudden increases
in conductivity values.
The concentrate stream from SWRO Unit is connected directly to the seawater waste pond. The
SWRO permeate flows directly into SWRO permeate tank. Depending on SWRO permeate tank
level, SWRO permeate flow is to be transferred to plant & fire water storage tank as per purpose.

3.2.6.

Energy Recovery Device with Booster Pumps with VFD
The concentrate from each train of the SWRO system will be routed to an energy recovery device
to reduce the overall power consumption of the HP pump driving motor of each train.
The energy recovery device will be based on isobaric technology. The concentrate from the
energy recovery device will discharged to the seawater waste pond.

3.2.7.

SWRO Flushing pumps
During a prolonged shutdown, the 1st SWRO membranes will be flushed with SWRO permeate
water. Flushing pumps will be provided for flushing of the SWRO HP pumps, SWRO trains,
ERD system and the high pressure piping system. The flushed water through the membrane will
be discharged to a trench that will drain into the seawater waste pond.
Two flushing pumps will be provided and will be suitably sized to flush one train at a time.
Flusing valve will be interlocked with the feed valve.

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3.2.8.

RO CIP System
A ‘Clean-in place (CIP)’ system will be supplied for membrane cleaning when this is required.
The CIP system will also incorporate a system for supplying preservation solution to the
membrane when is required. It will be permanently installed and will be capable of chemically
cleaning the biological, particulate or scale foulant from membrane at a regular interval and
restoring the differential pressure back to clean / normal value.
The system will be permanently sited. The site of the system will be dedicated area of the RO
building.
A pH sensor will be in the cleaning loop to monitor the chemical quality. The system will be
piped to each bank of RO modules by fixed pipework.
The CIP System for both SWRO and BWRO comprises of the following equipment:
• 1 x 100% RO CIP Tank
• 2 x 100% RO CIP Pumps
• 1 x 100% RO CIP Cartridge Filter

3.2.8.1.

RO CIP Tank
The tank will be complete with level transmitter (radar type) and a drainage disposal system for
used chemical disposal. A heater will be provided in the tank to maintain the cleaning solution at
the required temperature since conducting CIP operation using hot CIP solution will speed up the
process of cleaning of the RO membranes.
The appropriate chemicals for the foulant will be mixed with dechlorinated service water (or
permeate water) and circulated by pump through the membrane and then back into the CIP tank.

The cleaning sstem will be capable of cleaning one train at a time for up to about 20 hours
continuously. A continuous supply of water will be provided to the CIP tank.

3.2.8.2.

RO CIP Pumps
A set of RO CIP Pumps is provided to clean both SWRO / BWRO Membranes. The different
flow rate of each SWRO/BWRO shall be controlled by recirculation as well.

3.2.8.3.

RO CIP Cartridge Filter
RO CIP Filter is equipped with 5µm nominal cartridges to trap any particulates in the chemical
cleaning solution. This is installed in the RO CIP system to ensure that particulates present in
chemicals or carried over by the re-circulated solution from the RO membranes are trapped in
that cartridge filter. During CIP recirculation thru the RO membranes, a lot of biofilms and
oxides and many other particulates will come out from the RO membranes in the early stages of
the RO cleaning.

3.3.

BWRO System

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The BWRO System comprises of following major equipment:
• 2 x 100% BWRO Feed Pumps
• 2 x 100% BWRO Cartridge Filters
• 3 x 50% BWRO High Pressure (HP) Pump equipped with VFD
• 2 x 50% BWRO Trains
• 1 x 100% Degasifier with air fans
SWRO Permeate tank is routed to BWRO Units as pretreatment systems of MBP units. BWRO
units are composed of two (2) BWRO feed pumps, two (2) BWRO cartridge filters, three (3)
BWRO HP pumps with VFDs, two (2) BWRO trains.
3.3.1.

BWRO High Pressure Pumps with VFD
Two (2) BWRO train is supplied with three (3) BWRO HP Pump sized adequately for the duty.
The BWRO High Pressure Pump speed will be controlled by a variable frequency drive (VFD).
The PLC will be programmed to operate the pumps to maintain constant permeate flow
regardless of the feed water temperature or membrane age. The SWRO HP pump will not be
located on the RO frame or membrane rack, and VFD will be located in the MCC

3.3.2.

BWRO Trains
The BWRO Membrane assembly for each train will have two stages, 3:2 array of the membranes.
Each pressure vessel will contain 7 membrane elements. The entire RO train is stacked in frame
to facilitate installation, commissioning, operation and maintenance.
The train comprises of feed headers, permeate header and reject header. The concentrate control
valve on the BWRO train is controlled by its own flow loop to maintain constant recovery. This
control loop along with the VFD controlled pump will ensure that system recovery is maintained
at 87%.
BWRO train is provided with pressure transmitters at the membrane feed, total reject and total

permeate headers. The differential pressure between feed and reject will be continuously
calculated by PLC to provide an alarm to indicate when the membranes become due for cleaning.
Flow indicating transmitters are provided at each of the permeate lines on each stage of the
BWRO. The flow monitoring of permeate from each stage will provide an indication if there is a
malfunction in that specific stage which may be caused by one or any number of membranes in
that particular stage.
A conductivity analyzer will be provided at the common permeate header which collects
permeate from all stages of the BWRO. The analyzer will provide indication of the conductivity
of the produced water. A sample valve will be provided at each of the stages permeate line to
detect if there is malfunction in any membrane in any particular stage in case of sudden increases
in conductivity values.
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The reject stream from BWRO Unit is connected directly to SWRO feed line. The BWRO
permeate flows directly into the influent header of the Degasifier (which was considered BWRO
Permeate Tank) as well the plant & fire water storage tank

3.3.3.

Degasifier
A forced draft type of degasifier with air fans are provided to remove carbon dioxide from
BWRO permeate. The BWRO permeate “rains” into a bed of packing material, and the carbon
dioxide is forced to escape to the top of the column by an ascending flow of clean filtered air.
The basin is also considered as BWRO permeate tank.

3.4.

Mixed Bed Polisher Units
Mixed Bed Polisher (MBP) System comprises of the following equipment:
• 2 x 100% MBP Feed Pumps
• 2 x 100% Mixed Bed Polisher Vessels
• 1 x 100% Regeneration System with hot water tank
The Regeneration System comprises of the following equipment:
• 2 x 100% Regeneration Pumps
• 2 x 100% MBP mixing air blowers
• 1 x 100% Acid Dosing Tank (shared with wastewater neutralization acid dosing tank)
• 2 x 100% Acid Dosing Pumps (shared with wastewater neutralization acid dosing pumps)
• 1 x 100% Caustic Dosing Tank (shared with wastewater neutralization caustic dosing tank)
• 2 x 100% Caustic Dosing Pumps (shared with wastewater neutralization caustic dosing pumps)

3.4.1.

MBP Feed Pumps
A set of MBP Feed Pumps (2 x 100%) is provided for MBP Feed.

3.4.2.

Mixed Bed Polisher Units
The mixed bed polisher (MBP) consist of 2 x 100% vessels to polish the BWRO permeate using
anion and cation mixed resins. The MBP produces demineralized water suitable for boiler make
up. The feed to MB polisher is designed to be under a pressure of approximately 4-bars – enough
to pass through the MBP all the way to the demineralized water storage tank.

3.4.3.

Regeneration System

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The mixed bed units are regenerated using dilute hydrochloric acid and sodium hydroxide
approximately once per week. The regeneration process is fully automatic and initiated by a
totalizer or when the effluent exceeds the high conductivity setpoint alarm.
3.5.

Potable Water System
The Potable water system treats the SWRO permeate with carbon filtration and chlorine,
ensuring that it is suitable for potable water consumption in accordance with WHO guidelines
and Vietnamese regulation.
Potable Water System comprises of the following equipment:
• 2 x 100% Activated Carbon Filter Vessels
• 1 x 100% Sodium Hypochlorite Dosing System
Potable water from the treatment system is directed to a potable water storage tank from where it
is distributed to the potable water distribution lines.

3.5.1.

Activated Carbon Filter Vessels
Service water from plant & fire water storage tank passes through activated carbon filters (ACF)

for color and odor removal. Two (2) ACF – one operating and on standby – are provided.

3.5.2.

Sodium Hypochlorite Dosing System
Sodium hypochlorite will be dosed to maintain residual chlorine in the potable water line.
Sodium Hypochlorite Dosing System comprises of the following equipment:
• 2 x 100% Dosing Tank
• 2 x 100% Dosing Pumps
The filling of chemical solution into the dosing tank is done manually.

3.6.

Chemical Storage

3.6.1.

Acid Storage, Unloading / Transfer System
Acid Storage Tank of vertical cylindrical type are provided. Acid is supplied by chemical
delivery trucks.
There is one common fume scrubber connected to both tanks to remove any humidity from the
air inside the vessels. A service line is connected to the fume scrubber to scrub all the acid.

3.6.2.

Caustic Storage, Unloading / Transfer System
The system consists of Caustic Storage Tank of vertical cylindrical type. The tank is equipped
with flange immersion type heater to keep the caustic hot during cold weather to prevent
crystallization of the caustic.

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3.6.3.

Antiscalant, Coagulant, NaOCl Storage, Unloading / Transfer system
Antiscalant, Coagulant, NaOCl are supplied by liquid drum and these chemical drums shall be
placed at chemical storage area. Each chemical dosing tank shall be filled in with chemical drum
pumps.

3.6.4.

SBS, Coagulant aid Storage, Unloading / Transfer system
SBS, Coagulant aid are supplied by powder bag and these chemical bags shall be placed at
chemical storage area. SBS powder shall be dissolved in dosing tank with agitator and coagulant
aid shall be dissolved in auto dissolving unit.

3.7.

Final Treatment of Waste Water from WTP

3.7.1.

Neutralization Chemical Waste Water
All the chemical waste generated in the Demineralization Plant is transferred to the Chemical

Waste Water Pond through the drain pipes laid in concrete trenches. The Chemical Waste Water
Pond is sized adequately to hold and neutralize the waste generated by regeneration of a Mixed
Bed Polisher Unit, MBP non-chemical waste, ACF backwash waste, BWRO brine, and RO CIP
waste.
The system comprises of the following equipment:
• 1 x 100% Chemical Waste Water Pond (below ground),
• 2 X 100% Chemical Waste Water Transfer Pumps,
• 2 x 100% Acid Dosing Pumps (shared with MBP regen acid dosing pumps)
• 2 x 100% Caustic Dosing Pumps (shared with MBP regen caustic dosing pumps)
• pH transmitter, Level transmitter,
When the chemical waste water is received in the chemical waste water pond, initiation of
neutralization operation starts:
• The neutralization acid & caustic dosing pumps start
• The dosing of chemicals is initiated based on the pH reading from the pH Transmitter
• Wastewater recirculation start while acid / caustic addition takes place
Once the pH has reached acceptable value, the valve on the recirculation line closes and the
discharge side valve opens and the waste is discharged to the sump.

3.7.2.

Disposal of Sea Water Waste
All the sea water waste generated in the Demineralization Plant is transferred to the Sea Water
Waste Water Pond. The Sea Water Waste Water Pond is sized adequately to hold seawater waste

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generated from Auto Strainer backwash, SWRO brine, Thickener, filter press, clarifier, RO offspec waste and UF cleaning waste (seawater).
The system comprises of the following equipment:
• 1 x 100% Seawater Waste Pond (below ground),
• 2 x 100% Seawater Waste Transfer Pumps,
• 2 x 100% Portable Pumps,
• Level Transmitter,
Once seawater waste received & collected, and the level in the pond reaches the high level, the
transfer pump starts and waste water is discharged to the sump. The slope and drain pit at the
pond will be considered for solids settling and accumulation. The collected solids shall be
removed by potable pump regularly just in case.
4.

Operation
The Water Treatment System consists of three subsystems:
• Pretreatment System
• SWRO/ BWRO System
• MBP System
Each system will be controlled and monitored from the local control rooms via the PLC panel
with operator station. Each system will have PLC panel with operator station.
Appropriate interfaces between local control panel and the plant DCS will be provided
(hardwired & soft signals). The important status of the Water Treatment System will be
monitored from the plant DCS.

4.1.

System Operation

4.1.1.

Lamella Clarifier
If raw sea water becomes available, seawater is directly fed to the pre-treatment system with CW
pumps, along with all the chemicals dosing system in the pretreatment process will start. Acid
(HCl) is dosed prior to the inline static mixer located in the feed line to regulate pH value to an
optimum level for coagulation. The static mixer ensures proper mixing of the acid before it
reaches the clarifier. The water flows past the static mixer after, into a common feed channel
connecting the coagulation tank and flocculation tank. Sodium hydochlorite (NaOCl) and
Coagulant (FeCl3) are dosed in the coagulation tank for removal of dissolved iron and organic
and for increasing the size of particles for effective settling. Water in these tanks passes through a
flash mixer and overflows into the flocculation tanks with coagulation aid (Polymer) dosing to
interconnect and enmesh the colloidal particles into giant flocs.
Water in the flocculation tanks passes through a paddle type slow mixer and overflows into a
common feed channel. Water in the channel flows by gravity into the two clarifier basins

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equipped with inclined plates (lamella plates). Each clarifier basin is equipped with sluice gate to
isolate the whole basin. Afer the flocculation tank the treated water enters the clarifier section
where the influent is directed upwards through banks of inclined plates where the effluent water
exits at the upper surface and the solids (sludge) separate out, by gravity, falling to the bottom of
the clarifier.
The sludge scraper in operation continuously moves the precipitate settling on the floor of the
clarifier. Sludge buildup inside the clarifier basins is connected by pipelines to two sludge

disposal pumps. The sludge disposal pump transfers accumulated sludge to thickener and treated
by filter press finally.
Clarified water from the basins is collected into common channel where clarified water is piped
into a common clarified water pond by gravity.
Service:
Removal of particulates using a clarification process and
chemical aids
Inlet Flow:
2 x 550 m3/h (Inst. Max)
Equipment:
Coagulation Tank – Qty: 2 x 50%
Flocculation Tank – Qty: 2 x 50%
Agitators – Qty: 4
Clarifier – Qty: 2 x 50%
Clarified water pond – Qty: 1 x 100%
Sludge Disposal Pumps – Qty: 2 x 100%
Thickener – Qty: 1 x 100%
Thickened Sludge Transfer Pumps – Qty: 2 x 100%
Filter Press – Qty: 1 x 100%
Retention Times:
Coagulation Tank: 5 minutes
Flocculation Tank: 20 minutes
Chemical Dosing:
Coagulant: 11.2 liters/hr
Polymer: 770 liters/hr
Thickener hydraulic loading:
4 m3/m2/day
Transfer By:
Gravity to clarified water pond
Pumps for sludge waste

Next Process:
Ultra Filtration System
4.1.2.

Ultra Filtration (UF) System
Filtrate: The UF feed pumps are used to apply sufficient pressure to force feed water through the
pre-screen as well as through the UF membranes at the design flow. The feed water is forced
through the fiber into the lumen in an outside-in flow path. The filtered water flows from the UF
skid to filtered water pond. To prevent the excessive build-up of foulants on the membrane
surface, the filtration time is set based on projection results and adjusted based on operational
experience.
During filtration, the filtrate flow is monitored via a flow transmitter at feed line and controlled
with a flow control valve. If the filtrate flow rises above or falls below the upper and lower flow
limits respectively for an allotted amount of time, the system will shut down and go into fault.
Additionally, if the transmembrane pressure (TMP) rises above the set limit for an allotted
amount of time, the system will shut down and go into fault. An effluent turbidity analyzer will
monitor the filtrate quality and alert operators if turbidity rises above acceptable limits.

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Air Scouring: In order to maintain optimal performance and to prevent irreversible fouling, UF
membranes require cleaning at regular intervals.
Membrane aeration blowers provide low pressure air into the bottom of the membrane module
for air scouring. Air scour cleanings for the membranes incorporate a series of air scouring,

draining, and refilling to remove debris from the membrane surface and restore performance.
Maintenance Clean: Air scours alone are not sufficient to fully recover performance of the UF
membranes. Over time, a gradual decrease in membrane permeability is observed due to
irreversible fouling from adsorption on the membrane surface and within the pore structure. In
order to recover this performance, maintenance cleans are automatically performed at regular
intervals and consist of chemical soaking combined with air scouring. Although feed water can
be used for maintenance cleans, filtrate from the filtered water pond is recommended for this
application due to a lower amount of suspended solids and lower chlorine demand. The
chemicals used for maintenance cleans consist of hydrochloric acid (HCl) and sodium
hypochlorite (NaOCl). Sodium hypochlorite is used to oxidize organic foulants and acid is to
remove inorganic scaling. The waste from maintenance clean is discharged to chemical waste
pond and then to waste after neutralization.
As stated above, maintenance cleans are performed at pre-programmed intervals. However,
maintenance cleans can also be triggered by high TMP, which would result in situations where
the feed water is highly fouling (i.e. inordinately high levels of suspended solids). Typical
maintenance clean intervals range from 1-2 times per day. Frequency is dependent on feed water
quality as well as operational parameters.

Recovery Clean: At intervals determined by membrane performance and performance recovery
via air scouring and maintenance cleans, recovery cleans can be performed to remove foulants
that are not removed by the above mentioned methods. Recovery cleans are an aggressive
cleaning intended to restore the permeability of the membranes to near new levels.
Recovery cleans consist of aggressive air scouring and chemical backwashes combined with
extended chemical soaking at elevated concentrations. Elevated temperatures may also be used to
increase cleaning efficiency. Recovery clean frequency is site specific, but typically ranges from
monthly to semi-annually.
Service:
Inlet Flow:
Equipment:

Retention Times:
Transfer By:

Removal of particulates using a clarification process and
chemical aids
572 m3/h (Inst. Max, each)
UF Feed Pumps – Qty: 3 x 50%
Auto Strainers – Qty: 3 x 50%
UF Trains – Qty: 3 x 50%
Filtered Water Pond – Qty: 1 x 100%
UF Air Blowers – Qty: 2 x 100%
UF Cleaning Pumps – Qty: 2 x 100%
Filtered Water Pond: at least 20 minutes
Pumps to Filtered Water Pond for filtrate
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Next Process:

Gravity drain to Waste water ponds for UF waste
SWRO

Please find the typical deail UF cleaning procedure in Appendix. A.

4.1.3.

SWRO Units
During normal operation, the recovery is monitored by the flow transmitters at permeate and
reject lines. The recovery is automatically adjusted by reject control valve if it varies due to inlet
water condition changes. The conductivity analyzer continuously monitors the permeate
conductivity. If the conductivity of permeate is higher than preset value then, the permeate dump
valve opens after a time delay and permeate is allowed to drain for some time until conductivity
is restored to a value below the high conductivity alarm setpoint. If this does not occur, then the
unit shuts down and goes into flushing cycle.
The work exchanger type energy recovery device (ERD) exchanges the residual pressure from
the SWRO concentrate stream, boosting the filtered seawater supply pressure. As there are some
hydraulic losses in the membrane system and ERD, a booster pump is used to make up these
losses thereby producing the required influent pressure to the RO train.
The SWRO high pressure pumps and ERD booster pumps are VFD controlled to maintain a
constant permeate flow regardless of the feed water temperature or membrane age. The
concentrate control valve on the ERD is controlled by its own flow loop to maintain constant
recovery. These two (2) control loops ensure that the membrane flux rates and system recovery is
maintained in accordance with manufacturers recommendations.
RO cleaning is required to be done once every 3 to 6 months depending upon the conditions of
the RO feed water. When the normalized differential pressure across the RO membranes exceeds
15%, the PLC initiates a warning for operator in order to plan for system shut-down and cleaning.
RO cleaning or CIP starts by preparing alkali or acid solution using RO permeate un-chlorinated
water, turn on the heater inside the CIP tank, recirculation of the chemical solution until
temperature reaches 35°C and pH adjustment is finalized, and recirculation thru one stage of the
RO. Each stage of the RO should be cleaned separately, and the chemical solutions used for
cleaning the previous stage shall be discarded and fresh solution is prepared for the next stage.
The complete cleaning cycle has two steps for RO Unit. In the first step, the RO CIP Pumps
recirculate the solution through the fouled RO train, where each membrane gets cleaned
thoroughly. In second step, RO CIP Tank is filled with service water where it is pumped through
the RO train to flush the RO High Pressure Pump and the entire RO unit. The flushing ensures

that all residual RO cleaning solution from the RO vessels and feed/reject piping has been
flushed to drain.
Service:
Inlet Flow:

Dissolved solids removal for Serivce water application
340.7 m3/h (each)
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Equipment:

Vessel Arrangement:
Permeate Flow:
Transfer By:
Next Process:
4.1.4.

SWRO Feed Pump – Qty : 4 x 33%
Cartridge Filters – Qty: 4 x 33%
High Pressure Pump – Qty: 3 x 33%
RO Train – Qty: 3 x 33%
RO Pressure Vessels – Qty: 108 (36 per train)
RO Membranes – Qty: 756 (252 per train)
1st stage: 36 vessels

1st stage: 153.3 m3/h (each)
Pumps to plant & fire water storage tank /SWRO permeate
tank and BWRO
BWRO

BWRO Units
The primary objective of the BWRO membrane filtration system is to treat feed water relatively
high in dissolved solids to a quality acceptable for use as feed for the Mixed Bed Polisher (MBP)
unit. This includes the removal of small suspended particles that may have passed through the
upstream treatment processes.
The BWRO system consists of pressure vessels installed in trains for space savings and ease of
operation. The membrane material is constructed of polyamide thin film composite, which
provides good structural integrity and salt rejection.
The SWRO permeate is boosted to the feed pressure by the high pressure pumps and is fed to the
BWRO membranes. When water, at high-pressure, is fed to BWRO membranes, almost pure
water (permeate) passes through the membrane while salts are retained on the concentrate side.
Permeate from each BWRO unit is delivered to the downstream MBP units and rejects is
returning to SWRO feed.
Service:
Inlet Flow:
Equipment:

Vessel Arrangement:
Permeate Flow:
Transfer By:
Next Process:
4.1.5.

Dissolved solids removal prior to mixed bed demineralizer
71.3 m3/h (each)

BWRO Feed Pump – Qty: 2 x 100%
Cartridge Filters – Qty: 2 x 100%
High Pressure Pump – Qty: 3 x 50%
BWRO Train – Qty: 2 x 50%
BWRO Pressure Vessels – Qty: 10 (5 per train)
BWRO Membranes – Qty: 70 (35 per train)
1st stage: 3 vessels
2nd stage: 2 vessels
1st stage: 38.5 m3/h
2nd stage: 23.6 m3/h
Pumps to Degasifier basin and Mixed Bed Polisher
Mixed Bed Polisher

Mixed Bed Polisher Units
The normal operation cycle of Mixed Bed Polisher (MBP) units is 168 hrs. During this cycle,
conductivity, silica and flow at outlet of MBP unit are continuously monitored. If the
conductivity, silica and totalizer are not within preset limit, then the working unit is taken out of
service, and is regenerated until all conditions are met. During the regeneration process, the other
unit will be put in operation mode because there is a break tank (degasifier basin) between the
RO and the mixed bed units which the break tank water shall be consumed during 18 minutes of
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fast rinse (from MBP projection). Currently, the tank has 20 min retention time for the case of
one MBP unit is in operation and other unit is in regeneration (fast rinse).

From the service cycle to the end of the regeneration steps, the regeneration process consists of
the following:
1.

Service

2.

Backwash

3.

Settling

4.

Regeneration

5.

Displacement Rinse

6.

Drain

7.

Air Mix

8.

Settling

9.

Slow refill

10.

Fast refill

11.

Fast Rinse

12.

Back to Service

These steps will describe in details in the control philosophy, all other steps follow the traditional
steps implemented for typical mixed bed regeneration. Acid (Hydrochloric acid) and caustic is
used to regenerate the mixed bed.
1.

Backwash: The BW inlet & outlet valves open allowing BWRO permeate water from
the main header to BW the vessel. The backwash water source is used from Demin
water.

2.

Settling: The step is right after shutdown backwash. Backwashed and mixed resin shall
be separated by different density, more dense cation resin bids shall be settled faster
than anion resein bids.

3.

Caustic / Acid injection : The regeneration process is simultaneous and it’s a block flow:
Diluted caustic flows downward while diluted acid flows upward. Chemical wastes are
collected in the middle regenerant collector and is diverted to the chemical waste pond.

4.

Displacement Rinse : Displacement rinse will occur the same way as regeneration using
the demineralized water to displace all acid & caustic.

5.

Drain : The purpose of this step is to lower water levl of resin surface in the vessel
through intermediate collector for proper mixing.

6.

Air mixing : Blowers will deliver air to mix the resin after the vessel being drained after
drain.

7.

Settling : Air mix will continue, and it will stop suddenly to let the bed collapse after the

resin has mixed for some time.

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8.

Slow refill : preventing to separate mixed resin after mixing, slow demin water is
induced into the vessel through middle distributor. The air is vented from the vessel
during the filling.

9.

Fast refill : Once water level above certain level in the vessel, vessel is filling by MBP
feed pump from feedwater.

10. Fast rinse: The water will flow through the bed the same way as in the service flowrate
until conductivity of the water have reached the set-point required to put the bed back in
service. Once the MBP is regenerated, the vessel will be placed in standby mode and
ready for the next service cycle.
Service:
Inlet Flow:
Equipment:

Time between regenerations:

Chemicals
used
for
regeneration:
Backwash flowrate:
Backwash duration:
Air mixing velocity:
Total regeneration time:
Transfer By:
Next Process:

4.1.6.

Produce high quality process water for boiler feed
62 m3/hr (each)
Mixed Bed Polisher – Qty: 2 x 100%
MBP Regeneration /backwash pumps – Qty: 2x100%
Air Blowers – Qty: 2 x 100%
168 hours (7 days)
33% Hydrochloric acid (HCl)
45% Sodium Hydroxide (NaOH)
29 m3/hr
30 minutes
60 m/hr
< 4 hours
Hydraulics to Mixed Bed Polisher And Demineralized water
tank
Demineralized Water Storage tank

Potable Water System

Potable Water takes water from the plant & fire water storage tank by potable water feed pumps.
This water is treated by passing the water through activated carbon filters and dosed with Sodium
Hypochlorite for disinfection purposes.
The plant will optimize the applied chlorine dosing level based on the residual chlorine at the end
of the distribution line which depends on potable water demand and quality of water.
The plant will also monitor the chlorine level at the end of the distribution line and apply the
dosing requirement of the sodium hypochlorite to maintain residual chlorine in the potable water
line.
The effluent water from the potable water tank is monitored by a set of instrumentation which
consists of pH, residual chlorine, and conductivity. If the any of the readings is not within limits,
then the activated carbon inlet valves will close.
Service:
Inlet Flow:
Equipment:
Chemical Dosing rate:
Backwash rate:

Treat SWRO permeate for potable use
6 m3/hr (each)
Activated Carbon Filters – Qty: 2 x 100%
Sodium hypochlorite (NaOCl): 0.5 liters/h
6 m3/hr

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Backwash duration:
Backwash frequency:
Transfer By:
Next Process:

5.

10 minutes
Based on elapsed time or differential pressure
Filtrate to potable water tank
Potable Water Tank

Description of Chemical Storage & Filling
The storage tanks serve to store hydrochloric acid (33%) and caustic solution (45%) used for
water treatment plant (Pretreatment, RO, MBP, potable water and chemical waste neutralization
systems).

Typcial chemical filling procedure shall be recommendded as followings,
1.

Protective safety goggles face shield, protective suit, and rubber gloves must be worn
when working on the equipment or manually pumping chemical solution.

2.

The chemicals supplier, before beginning the filling process requires the authorized user
to give confirmation by his signature that release into a working plant will not constitute
a danger and will witness the filling process upon completion.

3.

The storage tanks and pipework shall be checked at initial filling by carrying out
successfully hydrostatic tests and checks with water.

4.

The filling into the storage tank shall be depending on the site condition; using own tank
lorry pump or using transfer pump

5.

The fillinig connection has to be identified for each chemical solution.

6.

The relative isolation valves shall be opened after connection accordingly, then the
discharge pump to be turned on.

7.

Operator must check the level of storage tank and discharge pump to be turned off, then
the relative valves to be closed out and hose to be disconnected.

Note that food grade chemical is required for potable water treatment only and industrial grade
chemical is recommended for others chemcial treatments.

6.

Instrument and Controls

6.1.

Instruments
Typical instruments necessary for the safe and efficient operation of the plant will be provided as
followings, however please refer to the Instrument List (NS2-YL00-P0GCF-120001) and Piping
& Instrument Diagram (NS2-XG02-P0GCF-120001) for the further details.
1.

Flow transmitter on inlet water supply for total amount of feed.

2.

Flow transmitter on product water of MBP for total amount of product.

3.

Level transmitter on each pond / storage tank

4.

Turbidity analyzer upstream / downstream of a lamellar clarifier.

5.

Turbidity / pH analyzer downstream of UF system

6.

pH / Cl2 / ORP / Conductivity / SDI analyzer upstream of SWRO

7.

Flow transmitter at SWRO permeate and concentrate

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