Transcript Document

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.
Filtration Spectrum
Atomic Mass Unit (amu) also
known as dalton (Da)
100
10000
108
1000000
109
Cell
fragments
Fulvic acids
Humic acids
Bacteria
Cryptosporidium
oocysts
Virus
Aqueous
salt
Giardia lamblia
cysts
Sugar
molecule
Fresh Point System
Metal
ion
Human
hair
Clay particles
Colloidal Silica
Suspended Solids Test (TSS)
Organic debris and bacterial flocs
Colloidal material
Silt particles
0.0001
0.001
0.01
0.1
Particle Size, µm
1.0
10
100
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 what’s 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 system’s 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 it’s
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 flow rates
• Protection not susceptible to common
substances in the water, such as hydrogen
sulfide (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.
FreshPoint Operation
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 postfilter 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
Outlet
Pressure
Tank
Drain
Closed /
Back Pressure
Open
Inlet
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
Outlet
Pressure
Tank
Drain
Closed /
Back Pressure
Open
Inlet
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
Outlet
Pressure
Tank
Drain
Closed /
Back Pressure
Open
Inlet
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
Permeate
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.
•
DRAIN
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 transmembrane 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
•
U440
10 gpm Flow
Control
INLET
The system should hold pressure to 14.5 to 15.0 psi after two minutes of decay.
Pressure Gauge
Air Tank/Air
Supply
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.
U440
Tank
Pump
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
–
•
Circulate cleaning solution through membrane
for 1 hour
–
•
•
(Start at about 2 gpm)
(may want to stop the pump
and let the cleaning solution
soak periodically)
Estimated Chemical Addition for selected cleaner
(20 Liters DI water)
Cleaner
Chemical Addition
Final pH or conc.
NaOH
80 grams NaOH
13
H2O2
33.4 mL 30%H2O2
500mg/L
HCl
166mL conc. HCl
1
H2SO4
56mL conc. H2SO4
1
Citric Acid
NA
1
NaOCl
80 mL bleach
200 mg/L
Table 1
•
Assume pure solid NaOH
Rinse
•
Assume 30% H2O2 solution
•
Assume Concentrated HCI solution (conc. HCl = ~ 12N)
Disinfect system with chlorine using
approximately 200mg/L
•
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
•
Rinse
•
Determine pressure vs flow curve of restored
membrane
•
Repeat as needed
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.