2 /GE /
2008년 2월 16일
EDI EVOLUTION
Pretreatment Cation IX Anion IX Mixed Bed
Pretreatment Mixed Bed
Caustic Acid
R.O. EDI
R.O.
Caustic
Acid
Pretreatment
3 /GE /
2008년 2월 16일
Role of EDI in RO/EDI SystemsRO initial demineralization step> remove ionic impurities, particles, high molecular
weight organics> rejection relative to feed
– ca. 95-99% rejectionEDI final demineralization step> remove residual ionic and ionizable impurities> must meet absolute specifications (resistivity,
sodium, silica, boron) required by customer’s processes.
4 /GE /
2008년 2월 16일
MK-3 FeaturesThe MK-3 has been designed to provide the same performance as the MK-2E, with a few additional benefits.
New Features• No concentrate recirculation required • No Brine injection • Improved stack energy efficiency• Less susceptible to thermal damage
MK-2E Features continued with MK-3• No stack bolt tightening• Guaranteed not to leak• No salt bridging
5 /GE /
2008년 2월 16일
Ease of Operation• No Concentrate Recirculation loop to control• No Brine Injection to operate & maintain • Once through design = less complicated system
Lower Operating Cost• No Concentrate Pump• No Salt • Lower system operating power ~ 0.5 to 1.0 kWhr/1000gal
MK-3 Benefits
6 /GE /
2008년 2월 16일
Process Principles- EDI ProcessFeed
HSiOHSiO33-- COCO33
== OHOH--
HH++
ClCl--SOSO44== NONO33
-- HCOHCO33--
-
Anion Membrane
Cation Membrane
NaNa++CaCa++++ MgMg++++ Na+Na+
Anion Membrane
Cation Membrane
High Purity Water
CaCa++++ MgMg++++ NaNa++HH++
Anode Waste
Concentrate
Anode (+)
Cathode(-)
Cathode Waste
High Purity Water
Concentrate
HSiOHSiO33--
COCO33== OHOH--ClCl-- NONO33
-- HCOHCO33-- HSiOHSiO33
--SOSO44==
HH++
7 /GE /
2008년 2월 16일
MK-2E Flow Path
MK-3 Flow Path
Co-currentvs. Counter-Current
Brine Recirculationvs. Once Through
8 /GE /
2008년 2월 16일
PretreatmentReverse Osmosis Permeate required to minimize:> Scaling> Organic fouling> Particulate and colloidal plugging> Chemical cleaning
Other Possible Pretreatment Combines w/ RO treatment> MicroFiltration/UltraFiltration> Cartridge Filters (CF)> Degasification – Membrane/NaOH Injection/Forced Draft> UV TOC Destruct (UV)> Softeners
9 /GE /
2008년 2월 16일
Feed Water RequirementsParameter MK-2E Ionics EDI MK-3Total Exchangeable 25mg/l 25mg/l Anion (TEA as CaCO3)Conductivity ( NaHCO3) <28 µS/cm <40 µS/cm <43 µS/cm Hardness (as CaCO3) <0.50mg/l <0.25mg/l <1.0mg/l Silica <0.50mg/l <1.0mg/l <1.0mg/lTOC <0.50mg/l <0.5mg/l <0.50mg/lTotal Chlorine <0.05mg/l <0.1mg/l <0.05mg/lTemperature 5 – 38 deg C 10 – 40 deg C 5 – 38 deg CpH 5 – 9 4 - 10 4 – 11Fe, Mn, H2S <0.01mg/l <0.01mg/l <0.01mg/lTurbidity <1 NTU <1 NTUMax Voltage DC 400 600 300Max Amperage 4.5 10 5.2
Typically all EDI state approximately the same inlet feed water requirements.
10 /GE /
2008년 2월 16일
New StacksMK-3 MK-3Pharm MK-3Mini
SAP P/N 3018626 3020056 3018627
Nominal Flow Rate 15 gpm 18 gpm 5 gpmFlow Rate Range 7.5 – 20gpm 7.0 – 20gpm 2.5 – 6.5gpm
Recovery 87 – 95% 87 – 95% 85 – 95%
Nominal Electrode Flow 0.35gpm
Typical Power Consumption 0.5 – 1 kWhr/1000gal
Concentrate Flow Counter current or co-currentDirection
Inlet Pressure 70 – 100psi
11 /GE /
2008년 2월 16일
E-Calc & Feed Water RequirementsMost important design factors that can be adjusted: feed ionic load (TEA), overall flow rate of system, flow rate per stack, silica guarantee & temperatureNew for the MK-3 E-Calc:
1. Basic PFD – showing projected flows and pressures2. Predicted maximum product Na, Cl & SiO2
concentrations as well as Product Outlet pressure.
E-CALC MK-3 rev 3.xls
12 /GE /
2008년 2월 16일
Design of GEMK3 Standard SystemsMechanical System Components
• E-Cell MK-3 StacksTM
• Hard Piping to stacks• Concentrate flows counter current to Dilute flow• Valves for isolation, control and sampling• Grounding
Electrical System Components
• Rectifier – 300VDC Maximum Output with Individual Current Monitoring• PLC – GE Fanuc – standard AB or Junction Box - optional• Instrumentation:
Basic Systems Premium SystemsPressure Gauges Pressure TransmittersRotameters with flow switches Flow Transmitters – All flowsFlow Transmitter on Dilute Out Resistivity sensorResistivity sensor DCS Interface
13 /GE /
2008년 2월 16일
Design of GEMK3 Standard Systems
Why are the GEMK3 systems designed with the Concentrate stream flowing counter current to the Dilute stream?
• Systems are designed for any hardness level feeding into the system – provides the largest amount of flexibility.
Why are the MK-3 stacks capable of having the Concentrate stream flowing in both counter-current and co-current to the Dilute Stream?
• Counter-current concentrate flow allows the MK-3 to have a much higher hardness tolerance
• Counter-current is the standard design• Co-current flow is only allowable if system is being fed with a double pass RO. • Provides some flexibility to retrofit current MK-1 and MK-2 series systems.
14 /GE /
2008년 2월 16일
Design of GEMK3 Standard SystemsWhat GEMK3 Standard System can not do:•Run co-current concentrate flow•Be used in Sanitary/Pharmaceutical applications•Be Hot Water sanitized•Use Stainless steel piping
For the above designs, the E-Cell system is a custom design.
When quoting a system requiring the above, please do not use the GEMK3 nomenclature.
Currently only have standard 60Hz, ANSI designs, we are continuing to work on 50Hz and DIN designs.
18 /GE /
2008년 2월 16일
Limitations of All EDI
Number 1 reason EDI systems fail in the field is feed water hardness.
> High hardness leads to scaling which can lead to thermal damage.
> System needs to be cleaned in a timely manner.> To minimize scaling, the MK-3 can operate in
counter current mode – all standard GEMK3 systems operate in counter current mode
19 /GE /
2008년 2월 16일
Limitations of All EDI
Number 1 reason EDI systems produce poor product quality in the field is high CO2 in the feed water.
> The resin within the stack can be overwhelmed > Most people only measure conductivity into the EDI
system, but fail to measure CO2.> Ensure that a proper projection is completed on the
feed water.> Check CO2 at regular intervals.
20 /GE /
2008년 2월 16일
Feedwater must be RO direct-coupled quality
Physical, biological and chemical contamination must be prevented
> Physical: PVC shavings; metal shavings; dirt; dust; pollen; welding debris; resin beads/fines
> Chemical: oxidizers such as chlorine; polyvalent cations, such as iron, manganese
Sources of contamination: open storage tank, degasifier, or softener without filtration before E-Cell
Limitations of All EDI – Feed Water