PORTABLE
WATER TREATMENT PRODUCTS - Options in Application and Technology
The range of portable water treatment products
has expanded significantly over the last several years. Much
of this expansion is due to the increased variety of technologies
and media available in the market. These technologies have enabled
manufactures to produce products with greater reduction capabilities.
Although new technologies and media have enabled
manufacturers to improve product performance there has been
little change in either the types of products or the basic applications.
Water bottles, gravity feed/pour through devices and hand held
pump/filter units continue to be used to replace bottled water,
during outdoor recreational activities and travel and for emergency
preparedness. In addition, sometimes 'questionable' quality
of bottled water and concerns about chemicals leached from plastic
containers has further increased the demand for this type of
product.
FOR MORE INFORMATION ABOUT
PORTABLE WATER FILTRATION SYSTEMS:
PORTABLE
WATER FILTRATION TECHNOLOGIES
There are multiple technologies and media currently
used in portable water treatment devices, some are common and
some are new. Each is used to address a specific contaminant
or water problem. In many cases several of these technologies
are used in conjunction with one another to create the end product.
Spun Polypropylene is used as a filter
to reduce sediment,
dirt and turbidity that may be present in the water source.
It is also useful as a pre-filter to protect a secondary stage
of treatment such as ceramic, porous molded plastic, carbon
block and/or membrane.
Porous Plastic technology can be applied
in a variety of ways, contingent upon the finished products
micron rating;
to reduce sediment, as a spacer between media layers, or as
a method of mechanically reducing cysts and bacteria. (I've
explained micron rating in my article...we may have to mix and
match a bit.)
Granular Activated Carbon is used to improve
taste and odor by reducing chlorine, industrial chemicals and
a multitude of organic contaminants. Additives to GAC may help
to reduce lead, some forms of heavy metals and additional contaminants.
GAC can also be used as Pre and Post Filtration for other technologies
and as a method for removing chlorine or iodine after disinfection.
Carbon Blocks perform the same function
as GAC. In addition, based upon micron rating, carbon blocks
have cyst and bacteria removal capabilities via mechanical filtration.
Ceramics will mechanically filter waterborne
pathogens such as cysts and bacteria. Their effectiveness in
a given application is dependent upon the choosing the right
micron rating for the application. Various micron ratings are
available.
KDF is generally used to compliment other
methods of treatment. It has a high capacity to remove chlorine
and selectivity for such contaminants as lead, arsenic, cadmium,
mercury, calcium carbonate and magnesium. In addition it is
bacteriostatic.
Membranes are in use or are being evaluated
for use in portable devices. Their sub-micron pore sizes enable
them to eliminate cysts, bacteria and in some cases viruses.
Sediment pre-filtration is necessary to protect the small pores
from clogging.
Iodinated Resin has proven to be an excellent
method of eliminating bacteria and virus from raw water. Though
effective, these resins have specific operating parameters.
Use outside of these parameters will negatively impact the products
effectiveness. A post media is used in conjunction with iodinated
resin to eliminate the concern of iodine or iodide in the product
water.
Ion Exchange Resins are used to remove
selected contaminants. Resins are manufactured with this selectivity
in mind. For example, a specific ion exchange resin is produced
to remove nitrates.
PORTABLE
WATER DEVICES
Pour Through/Gravity Feed Units
These units vary widely in size. One of the smaller
units is an 8 oz. inverted cup using carbon to improve taste
and odor. This unit has a 50 gallon capacity. An example of
the larger unit would be a terra cotta or stainless counter
top unit using ceramics with media capable of reducing a multitude
of contaminants including cysts, bacteria, lead, chlorine and
other heavy metals. The most versatile, durable and portable
of these large units is the Outback. This system breaks down
for storage and travel. It uses filters and chloro tabs to remove
bacteria, cysts, virus, chlorine and organic matter. The large
units have a 2,500 gallon capacity and replaceable components.
Many of the higher end products have been tested to ANSI/NSF
Standard 53 by credible independent laboratories.
Bottles
There are several portable bottle units on the
market. There is a broad range of performance and price - the
higher price not necessarily indicative of higher levels of
performance. Some bottles do their job using a single filter.
To achieve the same result others require that the filtration
component be changed once or even twice during a single use.
The most common performance claims are those of improved taste
and odor. This is achieved using a simple carbon filter that
fits inside the bottle. Other bottles are capable of bacteria
and cyst removal/reduction through the use of carbon blocks,
porous molded plastic or ceramics. Finally, in some cases the
bottles can reduce viruses through the use of membrane and/or
iodinated resin. There are several bottles that offer replaceable
filters while others have filters permanently affixed to the
unit, a straw or to the filter cap. One product actually opens
from the bottom of the bottle, allowing it to be used as a bottle
and as a pour through/gravity feed unit in conjunction with
a larger container. Again, third party testing is a critical
consideration when evaluating these products.
Pump/Filter Combinations
Pumps and pump/filter combinations usually use
a technology such as Carbon blocks, ceramics, porous plastic
elements or membranes to effectively remove protozoan cysts
and bacteria. It is generally a good idea to incorporate some
type of pre-filter to eliminate particulate that are larger
than the pore size that could cause premature clogging of the
filter. These products are used primarily in the outdoor specialty
markets. Because this application may entail challenging a product
with high levels of contaminants in 'worst case conditions'
the issue of performance testing becomes very important.
PRODUCT
VERSATILITY
Many of the available portable products can be
used in a multitude of applications. Within each product type
are individual products that are capable of producing potable
water from non-potable raw water sources, either by significantly
reducing bacteria or cysts or sediment etc. They can also be
used in non-traditional ways, both inside and outside the home
and in emergency or survival situations. A sports bottle can
be used to replace bottled water while at school, while traveling
or during any recreational activity. Some are designed specifically
to filter water for babies while others can double as gravity
feed treatment/filtration devices to fill larger water containers.
Some have capacities of as little as 25 gallons and some have
capacities as high as 200 gallons. Some remove only chlorine
while some have proven effective against bacteria, cysts and
virus. Countertop gravity flow devices can replace bottled water
without the connection to the faucet. They can treat, filter
and cool the water and are easily emptied and moved. There are
those that have the same range of performance characteristics
as sports bottles. Although their applications differ due to
their size their capacity is higher than that of a sports bottle.
Combination pump/filter units are useful in both outdoor and
emergency situation where the user might need to capture water
from streams, rivers, lakes, or other suspect water sources.
TESTING
Though virtually all of the technologies used
in portable filtration devices are also used in larger (Counter
top or Whole House) systems the amounts of media used are significantly
smaller, hence the portable systems generally have a much lower
performance capacity. Many of the devices using mechanical filtration
have capacities similar to their larger counterparts. In the
event that the product is to be used as a water purifier and
listed as such, the product must pass the stringent performance
evaluation required by the EPA. For all of these reasons it
is critical to ensure that portable units have been sufficiently
tested and evaluated by an independent third-party laboratory
and that the test results support any claims made by the manufacturer
and are available for general distribution to the buyer.
WHAT PORTABLE
PRODUCT DO I CHOOSE?
Use the following process to weed out the good
from the not so good.
Identify need:
What contaminant do you want to remove? What are the problems
in water supply in question (chlorine, lead, cysts, bacteria)?
Identify media or technology:
What technology is necessary to improve aesthetics and/or remove
contaminants.
Identify application:
Which type of product (or combination of products) will produce
the water you need (bottle, gravity feed system, etc). Once
this is decided focus on products using this technology or media
combination and making claims to remove the contaminants you
have identified.
Verify application given its operating parameters:
Make sure the product will work properly in the environment
where you will use it. For example, a water bottle using iodine
to remove bacteria will not be effective when used in freezing
temperatures by cross country or downhill skiers. It only 'works'
within a certain range of temperatures. Products may be rendered
less effective by a variety of conditions. These should be clearly
stated in the operating parameters furnished by the seller.
Verify the veracity of claims:
Ask the seller or the manufacturer to send you copies of third
party tests done by reputable labs showing the product can and
has performed in accordance with claims.
Evaluate ease of use:
Will product meet claims and be easy to use in the environment
of its intended use (outdoors, in an emergency situation, etc.)
Evaluate capacity in terms of need:
Will the product produce enough potable water to meet the your
needs in its intended application
Evaluate value versus price:
Don't assume that the higher price buys a 'better' product.
Competing products often use identical technology and differences
in price can be the result of fancy packaging or presentation.
Portable Water Filtration Systems and replacement
filters are available by contacting us:
1 (877) 377-9876
