Reverse Osmosis Design RO System Reverse Osmosis
- 1. RO SYSTEM
- 2. Fundamentals of RO What is Osmosis? The movement of a solvent (water in our case) across a semi permeable membrane from a solution of lower concentration to a solution of higher concentration that tends to equalize the concentrations of solute on the both sides of the membrane.
- 3. Osmosis
- 9. What will Reverse Osmosis remove from water? removing up to 99%+ of the dissolved salts (ions), particles, colloids, organics and bacteria from the feed water remove 100% of bacteria and viruses). An RO membrane rejects contaminants based on their size and charge. Any contaminant). RO system does not remove gases such as CO2 very well Reverse Osmosis is very effective in treating brackish, surface and ground water for both large and small flows applications. Some examples of industries that use RO water include pharmaceutical, boiler feed water, food and beverage.
- 10. Benefits of Using RO Energy Savings. Water Savings via increased Boiler cycles. Chemical Savings in the 25 to 50% range. Water reclamation via RO for reject water.
- 11. Membrane Processes Four common types of membranes: Reverse Osmosis Nano filtration Ultrafiltration Microfiltration
- 13. Pressure driven membrane processes
- 14. RO membrane
- 15. TYPES AND APPLICATIONS Cellulose Acetate membranes Polyamide and composite membranes
- 16. Cellulose Acetate membranes Dis-Advantage - Limited temperature - limitations PH (4-6) - High operating pressures - Silica rejection (80%)
- 17. Polyamide and composite membranes composite membranes - It consists of one polymer and has the advantage of obtaining less operational pressure with higher permeability Composite polyamide membranes (Thin film) - It consists of two polymer
- 18. TFC MEMBRANES Advantage - High temperature tolerance 45 digree - lower operating pressures - High PH range - low salts & silica passage Dis- advantage - Rough surface - Negative surface charge - Low chlorine tolerance
- 19. TFC MEMBRANES TYPES Seawater membranes. Brackish water membranes
- 20. Seawater Membranes Applications 1- High salinity : feed water TDS range (from 35,000 to 50,000 ppm) 2- Membranes Operation pressure: can go up to 1500 psi
- 21. Brackish Water Membranes TYPES 1- brackish, low energy membranes. Producing the same amount wit less pressure 2- brackish, high rejection membranes. 99.7 salt rejection which improve salt passage more than 67% 3- brackish low fouling membranes. neutral charge and feed spacer 31mil instead of 28 mil 4- brackish low differential pressure membranes. feed spacer reach to 34 mil 5- high productivity membrane modules Membrane surface aria 440ft2 instead of 365ft2 manufacturing chlorine treatment
- 22. Brackish water membranes Applications 1- Low salinity : feed water TDS range (from 4,000 to 5,000 ppm) 2- Membranes Operation pressure: can go up to 600 psi
- 23. R.O membrane modules Plate and frame modules. Tubular modules. Spiral wound modules. Hollow fine fiber modules
- 24. Spiral Wound
- 25. Spiral Wound
- 26. Spiral Wound
- 28. Customer Data Feed Water Type and Analysis Specify Water Quality and Quantity Needed After RO Treatment Indoor Or Outdoor Plant Operation Hours Daily Application
- 29. MEMBRANE FOULING CONSIDERATIONS Depending On Feed Water Source - Suspended solids - Dissolved matter
- 30. Suspended Solids Inorganic Particles Colloids Biological Debris Such as Microorganisms and Algae - The Turbidity and SDI should not exceed 1 NTU and 3 SDI units.
- 31. Dissolved Matter Highly Soluble Salts, Such as Chlorides, Sparingly Soluble Salts, Such as Carbonates, Sulfates, and Silica - Positive values of LSI indicate the possibility of calcium carbonate precipitation
- 32. Company Offer 1- Process Description 2- Membrane Projection 3- Chemical Consumption 4- Equipment List 5- Power Consumption List 6- Instrumentation list 7- Cable List 8- Power Components List
- 33. Company offer 9- Controller List 10- Process and Instrumentation Diagram (PID) 11- Mechanical Drawings 12- Electrical Drawings 13- Data Sheets
- 35. Water Problems Water Problems Feed Water Requirements Media Treatment Chemical Treatment Suspend Solids (TSS) NTU < 1 or SDI < 3 (5 max) Depth Filter Inject Coagulants/ Flocculants Chlorine (Oxidizers) 0 ppm Carbon Filter Sodium Meta Bisulfite (SBS) (inject 2 x Cl conc.) Hardness Softened Water Softener Antiscalant (~ 5 ppm) Bacteria 0 counts Ultra Violet Light or Ozone Chlorine
- 36. Water Problems Water Problems Feed Water Requirements Media Treatment Chemical Treatment Iron, Hydrogen Sulfide Fe (2+), 4 ppm Fe (3+), 0.1 ppm Manganese Green Sand 1) Chlorinate 2) Filter 3) Dechlorinate Silica Will precipitate at ~150 ppm NA 1) Special Antiscalant Dispersant. 2) Reduce RO Recovery Other Problematic Minerals
- 37. Equipment For Reverse Osmosis Desalination Systems •Pretreatment System •Reverse Osmosis System •Post Treatment System
- 38. Pretreatment Steps - The Pretreatment Process May Consists Of All Or Some Of The Following Treatment Steps: Removal Of Large Particles Using a Coarse Strainer. Water Disinfection With Chlorine. Clarification With Or Without Flocculation. Clarification and Hardness Reduction Using Lime Treatment. Media Filtration. Reduction Of Alkalinity By pH Adjustment. Addition Of Scale Inhibitor. Reduction Of Free Chlorine Using Sodium Bisulfite Or Activated Carbon Filters. Water Sterilization Using UV Radiation. Final Removal Of Suspended Particles Using Bag Filter and Cartridge Filters.
- 39. Pretreatment System Pumps Tanks Valves Filtration Chemicals Dosing Pumps Mechanical Mixer Pipe Size Instrumentation
- 40. Pretreatment Pumps Intake pump - VFD Feed pump - VFD BW pump - Suitable Dosing pump - Complete Dosing Set
- 41. Pretreatment Tanks Raw Water Tank Filtrated Sea Water Tank Dosing Tank
- 42. Pretreatment Valves Low Pressure pipe and fittings shall be schedule 80 PVC Butterfly Valves Ball Valves NR Valves Pressure Relief Valves
- 43. Pretreatment Filtration Screen - manual /auto Clarifier - Lamella Settler, Dissolved Air Flotation , Polymer Preparation and Coagulant Dosing Station Deep Filters - Sand, Activated Carbon, Softener, Iron Removal and Re-mineralization Filter Fine Filters - Bag and Cartridge Ultra-Filtration - In-Out/Out In
- 44. Pretreatment Chemicals Disinfection Coagulation Coagulation and Flocculation De-Chlorination Scale Inhibitor Ph adjustment
- 47. Pretreatment Pipe (Type/Size) Low Pressure pipe and fittings shall be schedule 80 PVC
- 48. Pretreatment Instrumentation Level switch (Low/High) all tanks including dosing tank Conductivity Meter feed water pH Meter feed water ORP Meter feed water Pressure Switch (Low/High) all pumps Pressure Gauge (Mechanical /Transmitter) Diff Pressure Switch pre-filtration Flow Meter (Mechanical /Digital) feed water
- 50. Equipment for Reverse Osmosis Desalination Systems •Pretreatment System •Reverse Osmosis System •Post Treatment System
- 51. Reverse Osmosis System Membranes Pressure Vessel Pumps Tanks Valves Energy recovery Pipe (Type /Size) Instrumentation
- 53. The Steps to Design a Membrane System Step 1: Consider feed source, feed quality, feed/product flow, and required product quality Step 2: Select the flow configuration and number of passes Step 3: Select membrane element type Step 4: Select average membrane flux Step 5: Calculate the number of elements needed Step 6: Calculate number of pressure vessels needed Step 7: Select number of stages Step 8: Select the staging ratio Step 9: Balance the permeate flow rate Step 10: Analyze and optimize the membrane system
- 54. Projection
- 55. Understanding The Difference Between Stages In a Reverse Osmosis (RO) System Difference between a 1 and 2 stage RO System: In a one stage RO system, the feed water enters the RO system as one stream and exits the RO as either concentrate or permeate water the second stage. The permeate water is collected from the first stage is combined with per meate water from the second stage. Additional stages increase the recovery from the syste m. Notice: RO System with Concentrate Recycle With an RO system that can’t be properly staged and the feed water chemistry allows for it , a concentrate recycle setup can be utilized where a portion of the concentrate stream is f ed back to the feed water to the first stage to help increase the system recovery.
- 56. Understanding the difference between passes in a Reverse Osmosis (RO) system Single Pass RO vs Double Pass RO with a double pass RO, the permeate from the first pass becomes the feed water to the second pass (or second RO) which ends up producing a much higher quali ty permeate because it has essentially gone through two RO systems. a double pass system also allows the opportunity to remove carbon dioxide gas from the permeate by injecting caustic between the first and second pass.
- 59. Codeline (Pentair) pressure vessel 4" CodeLine Membrane Housings - End Port / End Entry 20 bar - 41 bar - 68 bar - Side Port / Side Entry 20 bar - 31 bar - 41 bar 8" CodeLine Membrane Housings - End Port / End Entry 20 bar - 31 bar - 41 bar - 68 bar - 82 bar - Side Port / Side Entry 10 bar - 20 bar - 31 bar - 41 bar - 68 bar - 82 bar
- 60. RO System Pumps HP Pump - VFD 2nd Pass HP pump - VFD Booster Pump - VFD Flushing Pump Cleaning Pump - VFD
- 61. The Different Between Soft Starter and VFD Soft Starters is a solid-state device that protects AC electric motors from damage caused by sudden influxes of power by limiting the large initial inrush of current associated with motor startup. They provide a gentle ramp up to full speed and are used only at startup (and stop, if equipped). Variable Frequency Drives (VFD) is a motor control device that protects and controls the speed of an AC induction motor. A VFD can control the speed of the motor during the start and stop cycle, as well as throughout the run cycle.
- 62. RO System Tanks Suck Back Tank Flushing Tank Cleaning Tank
- 63. RO System Valves Butterfly Valves - shall be of 316 stainless steel construction with Teflon seat, body seal and stem seal. 3 Way Valves Ball Valves NR Valves Concentrate Valve - The reject- control valve shall be a 300# rated stainless steel single seat globe valve, with socket weld ends.
- 64. RO Energy Recovery PX Turbocharger
- 66. How It Works?
- 67. Turbocharger
- 68. How It Works?
- 70. Post-Treatment Pipe (Type/Size) Low Pressure pipe and fittings shall be schedule 80 PVC
- 71. Post-Treatment Instrumentation Level switch (Low/High) all tanks including dosing tank Conductivity Meter product line pH Meter product line Chlorine sensor product line Pressure Switch (Low/High) all pumps Pressure Gauge (Mechanical /Transmitter) Flow Meter (Mechanical /Digital) product line
- 73. Electrical Control Panel - The panel shall contain all the control logic circuitry for the R.O. system, wells, and post-treatment and distribution systems, with all switches, indicators, etc. mounted on the door. The following switches and indicator lights are required as a minimum: Main Power Breaker Main Power Indicator light Control Power Indicator Light Well Selector - ON/OFF/AUTO Plant Selector - ON/OFF/AUTO Distribution Pumps Selector - ON/OFF/AUTO RO Feed Pump Low Suction Pressure Indicator Light RO Pump High Discharge Pressure Indicator Light Low Feed pH Indicator Light
- 74. Company Offer 1- Process Description 2- Membrane Projection 3- Chemical Consumption 4- Equipment List 5- Power Consumption List 6- Instrumentation list 7- Cable List 8- Power Components List
- 75. Company offer 9- Controller List 10- Process and Instrumentation Diagram (PID) 11- Mechanical Drawings 12- Electrical Drawings 13- Data Sheets
- 78. Anti-Scalant
- 82. Equipment List
- 86. Cable List
- 88. Controller List
- 89. Process and Instrumentation Diagram (PI&D)
- 94. Data Sheets
- 104. What We Commission? Process Mechanical- Rotating equipment (pumps and motors), chemical feed systems, tanks, and piping/piping accessories, valves Electrical- Switchgear, generators, motor controls, low voltage distribution equipment Instrumentation and Controls for Process Equipment (HVAC/R is also commissioned but is outside the scope of this presentation)
- 105. Pre-Start-Up Checklist Corrosion resistant materials of construction are used for all equipment from the supply source to the membrane including piping, vessels, instruments and wetted parts of pumps All piping and equipment is compatible with designed pressure All piping and equipment is compatible with designed pH range (cleaning) All piping and equipment is protected against galvanic corrosion Media filters are backwashed and rinsed New/clean cartridge filter is installed directly upstream of the high pressure pump Feed line, including RO feed manifold, is purged and flushed, before pressure vessels are connected Chemical addition points are properly located Check/anti-siphon valves are properly installed in chemical addition lines
- 106. Provisions exist for proper mixing of chemicals in the feed stream Dosage chemical tanks are filled with the right chemicals Provisions exist for preventing the RO system from operating when the dosage pumps are shut down Provisions exist for preventing the dosage pumps from operating when the RO system is shut down If chlorine is used, provisions exist to ensure complete chlorine removal prior to the membranes Planned instrumentation allows proper operation and monitoring of the pretreatment and RO system Planned instrumentation is installed and operative Instrument calibration is verified Pressure relief protection is Installed and correctly set Provisions exist for sampling raw water, feed, permeate and concentrate streams from each stage and the total plant permeate stream
- 107. Pressure vessels are properly piped both for operation and cleaning mode Pressure vessels are secured to the rack or frame per manufacturer’s instructions Precautions as given in Loading of Pressure Vessels (Section 4.1 & 4.2), are taken Membranes are protected from temperature extremes (freezing, direct sunlight, heater exhaust, etc.) Pumps are ready for operation: aligned, lubricated, proper rotation Fittings are tight Cleaning system is installed and operative Permeate line is open Permeate flow is directed to drain (In double-pass systems, provisions exist to flush first pass without permeate going through the second pass) Reject flow control valve is in open position Feed flow valve is throttled and/or pump bypass valve is partly open to limit feed flow to less than 50% of operating feed flow
- 108. RO Troubleshooting
- 110. 1- Common Failures - Reverse Osmosis Systems
- 113. Chemical Cleaning
- 114. 2-Replacing Reverse Osmosis Membrane Elements shut down and drained remove both of the vessel end-caps. The elements can then be removed in their normal direction of flow. The U-Cup brine seals and the inter-connector O-Rings can be sparingly lubricated with glycerin to aid fitting. After element replacement is completed, any gaps should be limited with shims. The end caps can then be installed and the reverse osmosis system started. system should be filled with low-pressure water prior to starting the high-pressure pump. Any new elements should be rinsed to drain to remove any residual preservative chemicals.
- 115. 3- Replacing O-Rings - Reverse Osmosis Systems Commonly Cause abrasion and Failure Of The O-Rings That Seal The Inter-Connector To The Element Permeate Tube. A sudden Increase In Permeate Conductivity.
- 116. 4-Probing - Reverse Osmosis Systems To help identify problems affecting reverse osmosis systems. Probing involves inserting flexible tubing through one of the vessel permeate connections as a means of diverting the permeate from a specific area within the elements. This water is then tested for conductivity with a portable meter.
- 117. 5-Profiling a Reverse Osmosis Array the ability to isolate the problem to a particular location within the system provides valuable information as to the precise nature of the problem. This will help to determine the remedial action which may include cleaning, O-ring replacement, RO membrane element replacement etc.
- 118. 6- Shimming - Reverse Osmosis Systems This occurs because the pressure drop across the elements can cause them to compress Fouling or high flow rates can also result in significant movement, mostly when the reverse osmosis system starts-up.
- 125. Thank You