Understanding TDS in Water Quality

Total dissolved solids TDS in water indicate the concentration of inorganic and organic substances present in a dissolved form. Measured in parts per million (ppm) or milligrams per liter (mg/l), TDS plays a crucial role in assessing water quality and its suitability for various applications.

WATER PURIFIER

5/8/20241 min read

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TDS includes a variety of substances, such as:

Salts: sodium, potassium, calcium, magnesium, and chloride.
Metals: iron, lead, copper, and others.
Organic Matter: Dissolved organic compounds, nutrients, and contaminants.

Sources of TDS

TDS can originate from various sources, including:

Natural Sources: Minerals leaching from soil and rocks, organic materials from plant decay.
Human Activities: Agricultural runoff, industrial discharges, sewage, and water treatment processes.

Measurement

TDS is typically measured using:

Conductivity Meters: Since dissolved solids increase water's conductivity, these devices estimate TDS based on conductivity readings.
TDS Meters: Specific devices designed to provide a direct TDS measurement.

Importance of TDS

Water Quality Indicator: High TDS levels can indicate poor water quality and potential contamination. Low TDS levels are often preferred for drinking water.
Taste: TDS can affect the taste of water; some dissolved minerals may enhance flavor, while others may impart unpleasant tastes.
Effects on Health: While some dissolved solids are essential minerals, excessive concentrations can pose health risks and affect water's suitability for drinking and industrial use.

Acceptable TDS Levels

Drinking Water: Generally, TDS levels below 500 ppm are considered acceptable for drinking water; levels above this may affect taste and quality.
Irrigation and Industrial Use: Tolerance levels can vary significantly based on specific applications and crop types.
Home Appliances: High TDS levels (>500 mg/litre) result in excessive scaling in water pipes, water heaters, boilers, and household appliances such as kettles and steam irons. Such scaling can shorten the service life of these appliances.

How Can Water Purifiers Remove TDS?

A water purifier can use reverse osmosis (RO). RO uses a semi-permeable membrane to separate contaminants from water. Water pressure forces water through the membrane, allowing only pure water to pass while leaving behind dissolved salts, heavy metals, and other impurities. to remove the dissolved solids in the water that are responsible for elevated TDS levels. Reverse osmosis removes virtually all dissolved substances, including many harmful minerals, such as salt and lead. It also removes healthy minerals, such as calcium and magnesium; hence, RO purifier manufacturer companies started adding different mineral filters to add essential minerals back to filtered water.