Manganese is a water contaminant present in both well and surface waters, with levels up to 3 ppm. Manganese, like iron, can be found in organic complexes in surface waters. In oxygen-free water, it is soluble. In the oxidized state, it is insoluble and usually in the form of black manganese dioxide (MnO2) precipitate. An alert level for potential [....]
A method of reporting the concentration or "equivalent" weight of an ion or substance in a given volume of water as milli-equivalents per liter. Meq/l is calculated by dividing the mg/l by the equivalent weight of the ion or substance. Reporting the concentration of ions as meq/l is popular by RO chemists for determining whether a water analysis is [....]
A method of reporting the "actual" weight (milligrams) of an ion or substance in a given volume of water (liter). For dilute solutions, mg/l and ppm are equivalent. For example, a 1,000 mg/l (ppm) sodium chloride solution would result in a residue of 1,000 mg of NaCl after evaporation of one liter of water. RO chemists use mg/l frequently [....]
Hydrogen sulfide is a gas that causes the noticeable "rotten egg" smell in feed waters, with a threshold odor level of 0.1 ppm and a noticeable offensive odor at 3-5 ppm. Hydrogen sulfide is readily oxidized to elemental sulfur by oxidants (e.g. air, chlorine or potassium permanganate). Sulfur acts as a colloidal foulant and has a history of not [....]
The solubility of sparingly soluble salts increases with increasing feed TDS. To account for this effect in calculating the solubility of a salt (e.g. calcium sulfate, barium sulfate, strontium sulfate or SDSI), the Ionic Strength of a water is calculated. The Ionic Strength of each ion is derived by taking the ppm concentration of each ion (as calcium carbonate) [....]
Conductivity is a measurement of the ability of water to transmit electricity due to the presence of dissolved ions. Absolute pure water with no ions will not conduct an electrical current. Conductivity is measured by a conductivity meter and is reported as micromhos/cm or microSiemens/cm. Conductivity is a convenient method of determining the level of ions in a water [....]