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Level Measuring Methods | MAGNESIUM AND ALKALINITY | Top 6 Methods to Measure or Monitor Fluid Levels

Direct methods used for level measurement in a tank or storage vessel are

  1. Based on direct visual observation of indicators like
  •    Gauge stick
  •    Hook gauge
  •    Gauge glass

2. Based on the position of a detectable material

  •    Float Gauge

3. Buoyancy methods:

  •    Float Gauge
  •    displacer gauge

Indirect methods for measuring the liquid level in storage containers

  1. Utilizing the hydrostatic head developed by the liquid
  •   Pressure gauge
  •   Air- Trap
  •   Diaphragm box method
  •   Air or Gas purge method
  •   Differential Pressure method

2. By using radioactive radiation

3. Electrical properties like capacitance, conductance, and resistivity can be use used for level measurement

4. By using the property of reflection of waves from the liquid surface.

The above class of methods is used for measuring the level of fluids that are stored in a storage vessel and container in chemical industries, their even advanced method is practised for accuracy and precision. The methods discussed are easy and cheaper to use a service. In an evaporator, the liquid level should be maintained at a certain depth in the heat region so that the rate of heat transfer which it was designed will be achieved, if the case liquid level drops the coil used for the heating purpose may fail. Even controlling the pumping operation a level control system will help to start and stop the pumping of fluid into the storage tank. The simple level control can be made easily with minimum accessories.



Procedure – the magnesium content in terms of CaCO3 shall be calculated by subtracting the calcium content (in terms of CaCO3) from the total hardness content (in terms of CaCO3)


The alkalinity is determined by titrating against Std acid. The different types of alkalinities are determined by using, separately phenolphthalein and methyl orange as an indicator in two titrations and phenolphthalein after the addition of barium chloride in the third titration.


1. Phenolphthalein indicator
2. Std HCL acid – 0.02
3. Barium chloride sol – 10%
4. Methyl orange indicator


a) Take 100ml of the sample contained in a porcelain basin, add 1ml of phenolphthalein indicator and if a pink colouration is obtained, titrate with Std HCl acid, stirring with a glass rod, till the disappearance of pink colour is. Preserver the titrated solution. b) Then add 3 drops of methyl orange indicator and continue the titration until the colour changes from yellow to orange. c) Determine the alkalinity of phenolphthalein of another 100ml aliquot of the sample after adding a crystal of sodium sulphate and 10ml of barium chloride solution and stirring well for 2min. Disregard any reappearance of the pink colour.


Alkalinity to phenolphthalein (p) mg/l = 10 V1

Alkalinity to methyl orange (m) mg/l = 10 V2

Alkalinity to phenolphthalein after addition of barium chloride, mg/l= 10V3


V1 = volume in ml of Std acid used in (a)

V2 = volume in ml of Std acid in (b)

V3 = volume in ml of Std acid in (c)

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Aanchal Gupta

Welcome to my website! I'm Aanchal Gupta, an expert in Electrical Technology, and I'm excited to share my knowledge and insights with you. With a strong educational background and practical experience, I aim to provide valuable information and solutions related to the field of electrical engineering. I hold a Bachelor of Engineering (BE) degree in Electrical Engineering, which has equipped me with a solid foundation in the principles and applications of electrical technology. Throughout my academic journey, I focused on developing a deep understanding of various electrical systems, circuits, and power distribution networks.

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