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Fouling is any particles that are able to "cling" to the surface of the plate, but can be removed relatively easily by mechanical means such as hydro blasting or scrubbing with a soft bristle brush. Fouling can usually be taken care of during a typical maintenance cycle. 

Scaling is a very different phenomenon from fouling. Scaling occurs when a mineral film coats the entire surface of a heat exchanger. The most common forms of scale are usually from calcium-based salts such as calcium sulfate or calcium carbonate. They belong to a family of salts referred to as "reverse soluble salts". Reverse soluble salts act in the opposite way. As temperature increases, their solubility decreases in water. So, when you heat a water-based stream containing these salts, the salts begin to plate out onto the heat transfer surfaces. Once this happens, the heat transfer performance of your heat exchanger will decrease quickly. Scale cannot be removed by hydro blasting or your typical scrubbing. The only reliable way to remove these types of scale is by acid cleaning the plates. The scale has to be dissolved and carried away from the plate surface.

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In addition to that, most water source used in heat exchanger are not pretreated. Therefore, causing the hard water to deposit calcium carbonate that causes scaling. So a proper water pretreatment could prevent the fouling and scaling altogether. And preventive maintenance should be the best.. 

 

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On 5/10/2017 at 7:11 PM, Haris Shahid said:

Fouling is any particles that are able to "cling" to the surface of the plate, but can be removed relatively easily by mechanical means such as hydro blasting or scrubbing with a soft bristle brush. Fouling can usually be taken care of during a typical maintenance cycle. 

Scaling is a very different phenomenon from fouling. Scaling occurs when a mineral film coats the entire surface of a heat exchanger. The most common forms of scale are usually from calcium-based salts such as calcium sulfate or calcium carbonate. They belong to a family of salts referred to as "reverse soluble salts". Reverse soluble salts act in the opposite way. As temperature increases, their solubility decreases in water. So, when you heat a water-based stream containing these salts, the salts begin to plate out onto the heat transfer surfaces. Once this happens, the heat transfer performance of your heat exchanger will decrease quickly. Scale cannot be removed by hydro blasting or your typical scrubbing. The only reliable way to remove these types of scale is by acid cleaning the plates. The scale has to be dissolved and carried away from the plate surface.

Great..thank you!! Please continue answering the other questions as well.!

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Fouling is due to suspended solid which  get cling with operational object without any chemical reaction. Like clay, sand

 

Scaling is due to desolve solid like calsium , magnesium which get react with operational object.

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