Water Treatment

At EDS Pumps and Water Treatment Ltd we employ Certified Water Specialists who are trained and certified to analyze water test results. A Certified Water Specialist can make effective recommendations for treatment and custom-design a system that best meets your needs.

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The Importance of a Water Analysis

That's why a water test is necessary. Our in-house water testing lab can provide a quick analysis of many of the factors to be considered. As well, there are many government-approved labs for water testing where a full Potability Test can be performed. These results are used to design the most effective system for that particular set of water quality issues.

Always ask for a current Certificate of Potability for any property you are purchasing that has a well. Many financial institutions now require this certification before a mortgage is approved.

Chlorides & Sulfates

Almost all natural water supplies contain chlorides and sulfates. In small amounts, they are not significant, but in large concentrations they can cause problems. Low to moderate amounts add palatability to drinking water and are desirable for that reason. However, excessive concentrations make water unpleasant to drink.

Sulfates have a laxative effect and medicinal taste. Large quantities can also indicate that the water is extremely hard, has large amounts of sodium salts or acidity. Chlorides present in large quantities give water a salty taste -- brackish and briny. Both chlorides and sulfates contribute to the total mineral content and add to the electrical conductivity of water. They can be easily and substantially removed using reverse osmosis, deionization or distillation.

Corrosion

Corrosion is the eating away of metals due to electromechanical action. Oxygen causes rust to form on many types of metal. Acidic water can also cause corrosion. Galvanic corrosion occurs when two pipes of dissimilar metals are joined directly without the use of a pipe fitting designed to insulate different metals from one another.

Factors, such as temperature, can exacerbate water that tends to corrode. Temperature can increase the rate of corrosion three to four times the normal rate when the temperature of the water is increased from 60 F to 140 F.

Corrosive water can be treated in a number of ways. A neutralizer uses calcite and corosex to neutralize the acidic quality of water. Polyphosphates are used to form a thin, tight film on pipe walls that works almost like a glass coating keeping water away from metals that may corrode. This can be done in two ways. The first method uses a chemical feed pump to inject a chemical into the water to neutralize it. The second method uses a small tank that combines polyphosphates with calcium and magnesium. A mixing tank is advised to allow for an even dosage of polyphosphates.

Iron/Manganese: Ferrous, Ferric & Bacteria

Iron in water is a very common water quality issue and most common in groundwater sources rather than shallow wells. Where quantities of iron are found, it almost always indicates that manganese, too, is present. As there are three types of iron that can be present in water, it is prudent to determine which type, as they may be treated differently and some types are harder to remove than others.

Ferrous Iron: Iron that remains dissolved in the water when exposed to the air. Usually detected by the reddish-brown tinge it gives to water.

Ferric Iron: Iron that forms particles when exposed to the air. Usually detected as small black particles when water is allowed to settle.

Organic Iron or Iron Bacteria: Iron bacteria forms reddish-brown growths that may clog pipes and reduce flow rates. They can be detected in water that has been allowed to settle and appear as a reddish-brown "slug". This bacteria is not considered harmful, but it is not at all pleasant to drink.

Iron and manganese will often present themselves as staining on fixtures that is very difficult to remove. It may also indicate that the water is extremely acidic. It can cause bad taste and odours. Often, if organic iron or iron bacteria is present, it will clog pipes and reduce flow rates. For these reasons, the type of iron present should be determined as their treatment methods vary.

Iron and manganese can be treated in three different ways, depending on the type present and the quantity. Ion exchange water softeners and conditioners can be used if if the amount of iron and manganese is low -- less than 5.0 ppm.

The oxidation and filtration method uses an oxidizing agent -- usually chlorine or potassium permanganate -- that is added to the water. The process converts the ferrous iron into ferric iron -- remember ferric is the solid state of iron -- allowing for the iron to be filtered out through a resin bed. This type of water treatment is commonly called an iron filter.

The third method to remove iron and manganese from water is called sequestration, a process that uses polyphosphates in pot feeders or solution feeders. This method is not as common as the use of a softener or iron filter.

pH - Alkalinity & Acidity

The pH of water describes the hydrogen-ion activity. The pH scale ranges between 0 and 14 with 7 being neutral, less than 7 acidic and greater than 7 alkaline or base. Water with a pH of 10 is ten times as alkaline as a pH of 9. It is an exponential function. Alkaline water may be due to the presence of one or more ions, such as hydroxides, carbonates and bicarbonates. Strongly alkaline waters have an objectionable "soda" taste and feel "slippery". Alkaline water can cause excessively dry skin. Troublesome amounts of alkalinity can be removed by reverse osmosis.

Acidic water can cause serious corrosion of metal pipes and metal fixtures, and if low enough, will give a "sour" taste to water. A pH of between 5 and 7 can be treated with a neutralizer. As the water moves through the bed, it reacts with the filter material -- usually a mixture of calcite and corosex. Operating costs for this type of filter are nominal. Water with a pH lower than 5.0 is normally treated with an injected solution of soda ash that raises the pH to between 7.0 and 8.0.

Sodium

Sodium salts are present to some degree in all natural waters. Sodium is extremely soluble and increases its solubility as water temperature rises. Sodium salts do not form scale when heated nor do they produce curd when combined with soap.

High concentrations of sodium indicate there is a high total mineral content and tend to increase the corrosive action of water. In very high concentrations, sodium salts give water an unpleasant taste. They can also hamper the operation of water softeners in the removal of hardness.

Reverse osmosis and deionization remove sodium from water.

Staining

Staining is considered to be an aesthetic problem and does not usually make water unsafe to drink. Staining can be caused by a number of different factors. Red/brown staining on sinks, fixtures and clothing is usually caused by excessive iron in the water.

Blackish staining on fixtures and laundry is caused by excessive manganese in the water.

Yellowish cast to water and yellow staining on fabrics, fixtures, china and laundry is caused by tannins. Greenish or bluish stains on porcelain sinks and a blue-green cast to water is caused by copper.

Water spots on glassware and silverware is caused by hard water.

Treatment options are dependent on the mineral present that is causing the staining.

Tannins

Probably one of the most difficult to treat of the water quality issues, tannins are caused by water passing through rotten vegetable matter. The water picks up the colour and transfers it to the water. EDS Pumps & Plumbing Ltd has developed its own method of tannin removal. For more information, see Tannin Filters.

Total Dissolved Solids (TDS)

Total dissolved solids (TDS) is the weight of solids per unit volume of water which are in true solution.

A high TDS can indicate that there is a high concentration of sodium. A reverse osmosis system is useful to remove a high TDS caused by high sodium.

Multi-media filtration would be used with a high TDS caused from sediment and suspended solids.

Turbidity

Turbidity is the measure of the amount of light absorbed by water caused by suspended matter in the water. High turbidity does not necessarily make the water unsafe to drink; however it may not be all that appealing. Turbidity is caused by inorganic matter, such as clay, rock flour and silt, and organic substances like microorganisms, vegetable or animal matter.

Mechanical filtration will remove almost all forms of turbidity. Generally, these filters are installed at point-of-use rather than point-of-entry as they can cause a serious pressure loss.

Multi-media filtration is also effective to remove turbidity and produce a high-quality filtered water at a faster flow rate than conventional sand filtration.