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WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER CONSERVATION MEASURES
WATER CONTAMINANT LEVELS
WATER FILTERS, HOME USE
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PUMP REPAIR GUIDE
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PUMP SHORT CYCLING
WATER SOFTENERS & CONDITIONERS
WATER TANK REPAIR PROCEDURES
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WELL CHLORINATION & DISINFECTION
WELL FLOW RATE
WELL WATER PRESSURE DIAGNOSIS
WELL YIELD IMPROVEMENT
WINTERIZE A BUILDING
Here we explain how to install, use, & repair or maintain drinking water chlorinators or chlorine injection systems or alternatively, reverse osmosis systems or RO systems as two options for correcting unsanitary or unsatisfactory drinking water.
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This series of articles explains many common water contamination tests for bacteria and other contaminants in water samples. We describe what to do about contaminated water, listing common corrective measures when water test results are unsatisfactory.
We include water testing and water correction measures warnings for home owners and especially for home buyers when certain conditions are encountered, with advice about what to do when these circumstances are encountered.
A typical very effective treatment system for water contaminated by a persistent source bacterial contamination involves the injection of chlorine into the water supply, a holding tank to permit sufficient exposure time and concentration for the chlorine to do its work, and a post-processing charcoal filter to remove the chlorine from the water as it leaves the system.
[Click to enlarge any image]
Besides bacteria what else will a chlorinator remove from drinking water?
Chlorine treatment water purification systems will also remove modest levels of sulphur, sulphur generating bacteria, and other odors.
If the water has a high level of sediment, pre-filtering may be necessary to avoid clogging the charcoal with debris. There is an operating cost as the charcoal filters need to be changed periodically.
Also see WATER TREATMENT EQUIPMENT DISINFECTION - separate article
OPINION: A water treatment specialist will often test your water at no charge in order to develop a profile of the contaminants or aesthetic contaminants in water and thus to recommend a specific water treatment system.
This "free water test" service is a great deal for building owners and buyers so long as they realize that the water treatment company wants to sell water treatment equipment.
Some of our readers indicate that they were mistrustful of calling a company that sells water treatment equipment to ask for advice. Although we have encountered a few aggressive sales people, we have never found a water treatment company professional who gave dishonest advice about what was found in drinking water and what water treatment options can be provided.
Only a very foolish water salesman would be dishonest about what's in the water, but some companies may be reluctant to outline all of the treatment alternatives. If you're in doubt have some independent water tests done before spending on a costly system. If we had to live with bacteria in our water supply, this would be our treatment system of choice.
How does reverse osmosis water treatment work?
Reverse osmosis (RO) systems take advantage of the ability of water molecules to pass through a filter cellulose acetate semi-permeable membrane which at the same time keeps out many other (non-dissolved non-chemical) contaminants. "Semi permeable" means that the membrane is in effect an ultra fine filter whose openings pass water at a molecular level, leaving other larger molecules behind.
Water pressure (usually at 40 psi or more) forces water molecules through the membrane, leaving behind certain water contaminants including bacteria and sediment. Water on the output side of the filter has been treated or purified, depending on the capacity of the particular RO system.
Our photo ( left) shows a small point of use (POU) reverse osmosis water purifier installed below a kitchen sink. (Also notice that the corroded trap needs to be replaced.)
What contaminants do reverse osmosis water treatment systems remove?
RO filters themselves do not remove aesthetic contaminants such as dissolved chemicals, odors or bad tastes in the water supply. For this reason some reverse osmosis water treatment systems include additional stages of pre or post filtering to remove bacteria, chemicals, odors, tastes.
Reverse Osmosis Water Treatment System Clogging
Watch out for water high in bacterial contamination. Reverse osmosis systems are not usually recommended for water supplies that are high in bacterial contamination because bacteria build-up on the input side of the RO filter tend to block and clog the system.
Watch out: also for water supplies high in sediment, debris, chemicals, odors, or bad tastes. To avoid clogging the RO system a pre-filter to remove sediment may be needed, and to avoid chemical, taste, or odor complaints, a post-processing charcoal filter system may also be needed.
Reverse osmosis (RO) water purifiers (see sketch at below left) will remove nearly all water contaminants and also remove minerals from water leaving it soft. These systems do not discharge salt into the drain system, though they do discharge four gallons of waste water for every gallon of purified water produced.
Because the design and capacity of various RO systems varies, only if a reverse osmosis system is registered and listed as a water purifier, can it be relied on to handle bacterial contamination in the water supply.
Disposal of Reverse Osmosis Water Purifier Concentrate
As it becomes high in contaminants, water on the input side of the RO filter is flushed to a disposal location.
See REVERSE OSMOSIS CONCENTRATE WASTE DISPOSAL for a discussion of the effects of disposing of reverse osmosis water treatment equipment wastewater - RO concentrate - into septic tanks and drainfields.
OPINION: this method works well for some contaminants, as a point-of-use system. RO wastes quite a bit of water and does not address some chemical contaminants.
We don't know (yet) which uses more discharge water - a water salt-based water softener or an RO system. That's because the quantity of water "wasted" by a reverse osmosis system depends on the quantity of water that is demanded from its output side.
Also see WATER SOFTENERS & CONDITIONERS for more details.
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