Deaeration is based on two scientific principles. The first principle can be described by Henry's Law. Henry's Law asserts that gas solubility in a solution decreases as the gas partial pressure above the solution decreases.
The second scientific principle that governs Deaeration is the relationship between gas solubility and temperature. Gas solubility in a solution decreases when the temperature of the solution rises to saturation temperature. A deaerator utilizes both of these natural processes to remove dissolved oxygen, carbon dioxide, and other non-condensable gases from boiler feed water.
With these principles in mind, WTP Deaerators are designed with three-stage system of heating. |
| Application : |
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Removal of Dissolve gases like Oxygen & Carbon Dioxide from Boiler Make Up Water. |
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Deaerators are an integral and essential part of feed water heating systems in medium and high pressure boiler installations. |
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In modern low pressure boilers too, Deaerators are used to reduce the requirement of oxygen-scavenging chemical and thus minimize the solids content of boiler water. |
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| Effect of Dissolve Gases in the Boiler Make up water : |
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Threat of corrosion in boiler tubes and shelves, feed and condensate lines, heating systems, economizers etc. |
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As the solubility of gases decreases with increases in temperature, these gases are released in the boiler, thus presenting an immediate corrosion problem. They are carried over with steam to cause further problems in the condensate installation. |
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Addition of chemicals for corrosion control increases the dissolve solids in boiler water, thus resulting in increased
blow down and reduced thermal efficiency. |
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QUALITY OF DEAERATED WATER : |
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Carbon dioxide is reduced to levels not detectable by normal analytical procedures. |
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Oxygen residuals of 0.02 mg/L can be achieved. |
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Deaerator Head |
| Advantage of Deaerators : |
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Deaerator Head Internal Assembly |
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Steam – raising boilers and ancillary equipment are protected against corrosion. |
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Efficiency of boiler is improved. |
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Reduced solids concentration results in lower
blow down and reduced heat losses. |
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Deaerators offer a simple and economical means of removing oxygen and carbon dioxide using low pressure steam. |
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Requires very little maintenance. |
