Presentation on theme: "What is Ultrafiltration Ultrafiltration (UF) is a variety of membrane filtration in which hydrostatic pressure forces a liquid against a semipermeable."— Presentation transcript:
What is Ultrafiltration Ultrafiltration (UF) is a variety of membrane filtration in which hydrostatic pressure forces a liquid against a semipermeable membrane. Suspended solids and solutes of high molecular weight are retained, while water and low molecular weight solutes pass through the membrane. This separation process is used in industry and research for purifying and concentrating macromolecular (103 - 106 Da) solutions, especially protein solutions. Ultrafiltration is not fundamentally different from reverse osmosis, microfiltration or nanofiltration, except in terms of the size of the molecules it retains.
Your in-home waterworks Ultrafiltration membranes have long been employed by laboratories, hospitals, and municipalities to deliver high-quality water. FreshPoint now offers ultrafiltration on a smaller scale for your home, filtering all water at the point it enters your house. Depending on the properties of your local water, additional systems may be required to address issues such as iron staining, odor, or hardness. Often the best solution to ensure clean water throughout your house is to use a combination of technologies. How will you know whats best for your house? Your local water expert can help analyze your water and determine which combination is best for your particular needs.
How does FreshPoint work? Water enters the system from the bottom port, flowing into the straw-like hollow fibers inside the vessel. As water passes through the walls of the fiber, particles as small as 0.025 microns, including sediment, turbidity, and cysts, are trapped in the pores of the membrane, removing them from your water supply. After passing through the membrane, clean water flows up through the large perforated center channel. From there the clean water enters your existing plumbing system, reaching every point of use throughout your home. The system will periodically run through a self cleaning cycle to flush trapped particles from the porous fibers. This serves to maximize the systems filter capacity and extend the life of the membranes.
Common Questions Q. I have a filter on my kitchen sink. Why do I need anything more? A. Faucet filters (one type of Point of Use, or POU, filter) remove certain contaminants from your water. However, they do not remove everything. You may need additional filtration to address the issues specific to your water supply. Also, keep in mind that a POU filter works only at the faucet where its installed. FreshPoint provides clean water at every faucet throughout your house. Q. My water tastes and smells fine. Why should I have it tested? A. Although appearance, taste, and odor are strong indicators that your water may not be clean, they are not the only indication of trouble. Not all contaminants cause your water to taste or smell bad. Many go undetected. Professional lab tests are the best way to learn whether your water is clean. Call your local water expert to find out which tests are most important in your area.
Common Questions Q. What will happen to my water pressure? A. One of the unique advantages of hollow-fiber membranes is their ability to filter very small particles while providing high flow rates throughout your home. As local water conditions change, so do local plumbing codes. Be sure to consult your local water expert to determine what size system is right for your home and your family. Q. Will the FreshPoint system increase my water usage? A. Unlike traditional backwash filters, the FreshPoint system uses fewer than 4 gallons of water during the fl ush cycle. This means less waste and more clean, filtered water. Q. How often does the whole-house filter need to be changed? A. The life of the filter element depends on many factors including the local water quality, other water systems in the plumbing, and how much water is used. When applied correctly, the FreshPoint system should provide three to five years of clean, filtered water before the element needs to be replaced.
FreshPoint Applications Known problem waters – The FreshPoint is NSF certified for removal of cysts (NSF 53), turbidity (NSF 53), and particulate removal (NSF 42, class I) Pre-Filter – Installed prior to one-time-use specialized filters and other sensitive equipment. Barrier Filter – Provides barrier on clean water supplies against compromises to the water system – Note - This product is not certified as microbiological purifier and should not be applied as stand-alone disinfection solution for microbiologically unsafe water.
FreshPoint Ultrafiltration System The system can be applied to solve known water problems including high turbidity, suspended solids, and certain microbiological contaminants. It can also serve as a flushable prefilter to extend the life of media filters downstream. > 98% reduction of 0.025 micron particles* > 99.99% (> 4 Log) reduction of 0.065 micron particles* Forward-flush and back-flush cleaning cycles provide extended filter life in a wide range of applications. * Performance based on MS-2 (25 nm) and PRD-1 (65 nm) virus particle tests
FreshPoint Ultrafiltration System Proprietary high-flow hollow fiber membrane module (32mm permeate tube) Professional-grade housing, controller and flush valve Metered self-cleaning cycle flushes only when needed Day override feature flushes module daily with fresh water when system is not in use Peak flow rates up to 10 gpm (2271 L/h)
FreshPoint Membrane Technology Removes turbidity, cysts, and other particles down to 0.025 micron in size Requires only normal line pressure to operate Protects during power outages or intermittent power Retains natural mineral content of the water High surface area and tolerance to plugging Low pressure drop / High ow rates Protection not susceptible to common substances in the water, such as hydrogen sulde (H2S), natural organic matter (NOM) and total dissolved solids (TDS)
FreshPoint Membrane Technology Multi-bore membrane structure combines seven single capillaries into one resistant structure, maximizing membrane integrity and eliminating the potential for fiber breakages. Unlike traditional hollow fiber capillaries, the FreshPoint membranes are encased by a foam support structure located in between the capillaries. The foam structure provides a permeabilty that is approx. 1000 times higher than the filtration surface so that an equal distribution throughout the whole cross section of the fiber can be guaranteed. The inner layer of the seven capillaries represents the very thin active ultrafiltration surface.
Professional Metered Controller Metered self-cleaning cycle flushes only when needed, using less than 10 gallons per flush cycle (1 min. flush) Day override feature flushes module daily with fresh water when system is not in use Environmental cover is suitable for indoor or outdoor applications. Bright 7 digit VFD display with user panel utilizing LED status/programming indicators. A regeneration lockout input is available. Diagnostic display for Totalized Flow, Instantaneous Flow Rate, Days Since Last Flush, Prior Service Volume, Previous Days Water Usage Programmable Auxilliary relay
FreshPoint System Less Controller In order to offer a system that provides the maximum flexibility in design and application, the FreshPoint system is also offered in a less-controller version. This version is simply a housing, membrane element, brackets, and solenoid valve. This system can be triggered to flush from the auxilliary relay of any Fleck softener or filter control with XT or NT controls. The flush can also be triggered off a differential pressure switch or using manual ball valves. In this configuration, the FreshPoint systems can also be configured to operate in parallel plumbing to provide higher flow rates, with the flush triggered from a single meter and controller
High Pressure Housing The high-performance industrial fiberglass housing is pressure rated to 300 psi. Inside the housing, the membrane is sealed with double radial o-rings, minimizing the potential for leak paths. Quick-connect end caps allow the membrane to easily be removed for cleaning or replacement.
Pretreatment Guidelines Pretreatment is a key factor in maximizing ultrafiltration membrane integrity and element life. In all municipal and well water applications, a 50-10 um pre-filter is recommended to protect the membrane. When high iron or magnesium content are present additional oxidation and filtration are recommended. When feed water is surface water, a multimedia filter is strongly recommended. In some instances flocculation may also be used before sand or multimedia filtration. If a sand or multimedia filter are applied prior to the FreshPoint, a screen at 50-100 um is required to ensure that sand leaked from sand or multimedia filter cannot reach the surface of UF membrane. Chlorination or ultraviolet sytems may also be used for post- filter disinfection.
Service Cycle During service operation the membrane will filter particles down to.025 microns (25 nanometer) at flow up to 10 gpm*. To maximize membrane capacity and service life, a metered flushing cycle is controlled using an advanced controller and high-performance turbine meter. The self-cleaning forward and backflush cycle are initiated when the programmed capacity of the membrane is reached. * Flow Rate @ 15 psi drop
Service Cycle Closed / Back Pressure Open Pressure Tank Outlet Inlet Drain
Backflush Cycle In order to avoid clogging of the membranes, a backflush sequence is necessary at periodic intervals. The backflush sequence forces the filtrate in "reverse direction through the membrane to loosen particles from the surface and rinse off sediment build-up. Filtrate
Back Flush Cycle Closed / Back Pressure Open Pressure Tank Outlet Inlet Drain
Forward Flush Cycle A Forward Flush, in which raw water passes through the capillaries at a high speed, scours particles from the membrane surface and rinses them from the system. Conducted directly after a Backflush, this process thoroughly removes particles from the membrane surface and removes the loose particles from the fibers.
Forward Flush Cycle Closed / Back Pressure Open Pressure Tank Outlet Inlet Drain
Flush Settings The FreshPoint should to be flushed on a schedule dependent on the quality of water being treated. Default Factory Settings: – Flush Frequency: 100 gallons – Flush Duration: 0.5 minutes – Day Override: 1 day These settings may need to be adjusted based on the analysis for the water treated and practical experience with fouling. In all installations, the FreshPoint is should be set to flush after 24 hours without a flush, regardless of the volume flowed. A post-ultrafilter pressure tank is recommended to ensure sufficient flow and pressure to the home during a flush cycle. The backflush surge tank will perform the same function.
Plumbing Guidelines Assess the household water use, especially peak water draw. The standard single-element FreshPoint is sized for 10 gpm peak capacity flow. Water draw in the house that exceeds peak capacity will have the effect of reduced pressure and volume delivery at the open taps. All three FreshPoint housing ports on the system (inlet, filtrate or outlet, and drain) are 3/4 NPT connections, and the plastic meter is a 1 NPT connection. A 10 gpm flow control is included to be installed on the inlet of the FreshPoint to ensure the membrane operates in an efficient manner. A 7 gpm flow control is included to be installed on the drain line to maximize water efficiency and assure proper flushing rates are achieved. Ensure the drain selected has the capacity for this flow rate.
Plumbing Guidelines If fouling potential is high, it is recommended that a backflush tank is installed. The installation of a pressure tank aids in the flushing process of the membranes, thereby extending the membrane life. The pressure tank should be sized based on flushing volume requirements (5-10 gallons is typically recommended). For all installations without a backwash tank, a post-ultrafilter pressure tank is recommended to maintain household pressure during a flush cycle. The system must be protected from possible back contamination by the installation of an air gap between the FreshPoint drain connection and the drain line.
Additional Water Treatment Devices It is preferable to treat the water ahead of softeners, iron filters, and other water treatment devices, as the removal of particulates generally improves their performance. Installation ahead of them is not a necessity in most cases. Installation downstream of a chlorinator runs the risk of oxidative attack of the membrane, shortening the membrane life depending on chlorine level, time of contact and temperature. The FreshPoint can withstand a continuous dose of 1.0 mg/L (or ppm) of free chlorine, but continuous exposure to higher level of free chlorine or other oxidizing chemicals can shorten the life of the membrane.
Membrane Maintenance The FreshPoint must be kept in a wetted condition. Once installed or during service and maintenance activities, do not allow the FreshPoint to sit completely drained for extended periods (greater than 12 hours). Failure to do so may damage the system. If the FreshPoint is drained or out of service for an extended period of time, the installer/dealer should put a preservative into the system to keep the membrane wetted and prevent microbial growth. A 0.1% sodium bisulfite solution is recommended. A 0.1% sodium bisulfite solution would be 1 gram of sodium bisulfite added to one liter of water (approximately ten liters are required). Prior to putting the FreshPoint back into service, the system should be flushed and sanitized per the instructions in the Installation section of this service manual.
Integrity Testing Introduction This is a simple pressure-hold or vacuum-decay test designed to identify gross defects in the membrane, or element/device seals. General The test requires that the membrane be both fully wet-out (all pores full of water) and is more sensitive if the device is drained. The more parts of the entire device that is tested, the better – in order to include seals as potential source of leaks. This test does not require the visual detection of a bubble, instead it measures the loss of pressure or vacuum over time via a gauge. A certain amount of pressure loss will occur in an intact system from simple diffusion of air through the water trapped in the membrane pores (baseline decay). But much more will occur from membrane flaws or broken seals. A rapid loss compared to an integral device is the indication of a leak. Standard values for leaks and baseline decay should be set with experience. The procedure below covers only positive pressure use, but is easily modified to allow vacuum use. Vacuum instead of positive pressure allows testing of devices with only one side drained. Vacuum use also reduces chance of contamination by materials or microbes in the pressurized air. To prevent contamination, use either a clean air source or a 0.2 micron filter on the air source.
Integrity Testing Equipment Pressurized air source (15-20 psig, with 3+ scf of volume) with pressure regulator. Gauge (0-15 psig or more, with sensitivity to 0.5 psi) mounted in line between the valve and either the feed or drain port connection. Positive shut off valves (a quality ball valve works well), one mounted between air source and gauge and others on the plumbing connected to both side ports. Stopwatch, or watch with second hand. Procedure 1. Orient the device vertically. 2. Assure the membrane is fully wet by having recently operated it to at least 15 psid trans- membrane pressure. 3. Drain the device on both the filtrate and feed side (10-15 minutes) 4. Carefully pressurize the feed side (fiber lumens) to a 15 psig. 5. Close the valve between air source and gauge, simultaneously begin measuring time. 6. Note the pressure at 60, 120 and 180 seconds. Record. 7. Relieve air pressure before disconnecting Pass/Fail The system should hold pressure to 14.5 to 15.0 psi after two minutes of decay.
Membrane Cleaning Procedure Perform complete backflush. Set up cleaning system as shown in Schematic 1 – Pump and plumbing should be chemically compatible Determine pressure vs flow curve of fouled membrane Determine if cause of fouling is Inorganic or Organic – Inorganic - use acid (HCl, H2SO4, or citric acid)(minimum pH of 1) – Organic - use NaOH (maximum pH of 13) – May consider using Hydrogen Peroxide or Chlorine if an acid and/or base is not sufficient. Schematic 1
Membrane Cleaning Procedure Make up cleaning solution per table 1 – (approximately 20L) – (5 gallons = 18.9 liters) Start pump to circulate cleaning solution through the membrane – (Start at about 2 gpm) Circulate cleaning solution through membrane for 1 hour – (may want to stop the pump and let the cleaning solution soak periodically) Rinse Disinfect system with chlorine using approximately 200mg/L Rinse Determine pressure vs flow curve of restored membrane Repeat as needed Estimated Chemical Addition for selected cleaner (20 Liters DI water) CleanerChemical AdditionFinal pH or conc. NaOH80 grams NaOH13 H2O233.4 mL 30%H2O2 500mg/L HCl166mL conc. HCl1 H2SO456mL conc. H2SO41 Citric AcidNA1 NaOCl80 mL bleach200 mg/L Assume pure solid NaOH Assume 30% H2O2 solution Assume Concentrated HCI solution (conc. HCl = ~ 12N) Assume concentrated H2SO4 (conc. H2SO4 = ~ 36 N) Assume pure solid citric acid Assume household bleach NaOCL (as active chlorine) Make 0.1N of all basic and acidic solutions Table 1
FreshPoint Ultrafiltration System The PENTEK FreshPoint Ultrafiltration System provides complete point-of-entry filtration proven to reduce turbidity, particulates and cysts for safer, cleaner water at every tap. The system employs flushable hollow fiber ultra-filtration membrane technology to filter impurities as small as 0.025 microns.