A salinometer is a device designed to measure the

salinity Salinity () is the saltiness or amount of salt (chemistry), salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensio ...

, or dissolved

salt In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as r ...

content, of a solution. Since the salinity affects both the

electrical conductivity Electrical resistivity (also called volume resistivity or specific electrical resistance) is a fundamental specific property of a material that measures its electrical resistance or how strongly it resists electric current. A low resistivity in ...

and the

specific gravity Relative density, also called specific gravity, is a dimensionless quantity defined as the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for solids and liquids is nea ...

of a solution, a salinometer often consist of an ec meter or

hydrometer A hydrometer or lactometer is an instrument used for measuring density or relative density of liquids based on the concept of buoyancy. They are typically Calibration, calibrated and Graduation (instrument), graduated with one or more scales suc ...

and some means of converting those readings to a salinity reading. A salinometer may be calibrated in either micromhos, a unit of

, (usually 0-22) or else directly calibrated for salt in 'grains per gallon' (0-0.5). A typical reading on-board ship would be 2 micromhos or 0.05 grains per gallon. A reading of twice this may trigger a warning light or alarm.

Applications

Fresh water generators (

Evaporators An evaporator is a type of heat exchanger device that facilitates evaporation by utilizing conductive and convective heat transfer, which provides the necessary thermal energy for phase transition from liquid to vapour. Within evaporators, a ci ...

) use salinometers on the distillate discharge in order to gauge the quality of the water. Water from the evaporator can be destined for potable water supplies, so salty water is not desirable for human consumption. In some ships, extremely high quality distillate is required for use in water-tube boilers, where salt water would be disastrous. In these ships, a salinometer is also installed on the feed system where it would alert the engineer to any salt contamination. The salinometer may switch the evaporator's output from fresh-water to feed-water tanks automatically, depending on the water quality., pp. 212-213 The ''higher'' quality (lower salinity) is required for the

boiler feedwater Boiler feedwater is the water which is supplied to a boiler. The feed water is put into the steam drum from a feed pump. In the steam drum the feed water is then turned into steam from the heat. After the steam is used, it is then dumped to the ...

, not for drinking.

References

External links

History of the development of salinometers

Modern oceanographic salinometers
Measuring instruments {{Measurement-stub

Applications

See also

References

External links