# ما الفرق بين كلا من scaling و fouling و deposition و precipitation



## ويندوز مان (18 سبتمبر 2012)

السلام عليكم

ما الفرق بين كلا من

scaling
و 
fouling
و 
deposition
و 
precipitation

منتظر الرد ضروري


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## ويندوز مان (20 سبتمبر 2012)

بعد بحث طويل في كتاب شركة DOW 
Filmtec technical manual
للتحمبل
http://www.dow.com/scripts/litorder.asp?filepath=/609-00071.pdf

أولا Scaling
تعريفه ص148


Scaling is a water chemistry problem originating from the precipitation and deposition of sparingly soluble salts. The typical scenario is a brackish water system operated at high recovery without proper pretreatment. Scaling usually starts in the last stage and then moves gradually to the upstream stages. Waters containing high concentrations of calcium, bicarbonate and/or sulfate can scale a membrane system within hours. Scaling with barium or with fluoride is typically very slow because of the low concentrations involved.​


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## ويندوز مان (20 سبتمبر 2012)

اضافة اخري بالنسبة للـ Scaling

العناصر التي تسبب Scaling هي Ca HCo3 SO4 Ba Sr S

الــ Scaling يحدث في نهاية الغشاء من ناحية خروج الماء(عند زيل الغشاء ) المالح ويكون له ملمس خشن مثل ملمس الورقة التي عليها رمل

ص 139

Open a pressure vessel at the concentrate side: scaling feels like sanding paper to the touch. 


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## ويندوز مان (20 سبتمبر 2012)

تعريف أخر للـ Scaling

ص 162

The build-up of precipitated salts on a surface, such as membranes, pipes, tanks, or boilercondensate tubes ​
تراكم الأملاح المترسبة على سطح الأغشية والأنابيب والخزانات وأنابيب المرجل​


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## haider2012 (5 أكتوبر 2012)

شكرا على المجهود الرائع


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## maidi (7 أكتوبر 2012)

وهذه الإضافة منقولة :

Fouling is the accumulation of unwanted material on solid surfaces to the detriment of function. The fouling material can consist of either living organisms (bio-fouling) or a non-living substance (inorganic or organic). Fouling is usually distinguished from other surface-growth phenomena in that it occurs on a surface of a component, system or plant performing a defined and useful function, and that the fouling process impedes or interferes with this function.
Other terms used in the literature to describe fouling include: deposit formation, encrustation, crudding, deposition, scaling, scale formation, slagging, and sludge formation. The last six terms have a more narrow meaning than fouling within the scope of the fouling science and technology, and they also have meanings outside of this scope; therefore, they should be used with caution.
Fouling phenomena are common and diverse, ranging from fouling of ship hulls, natural surfaces in the marine environment (marine fouling), fouling of heat-transfer components through ingredients contained in the cooling water or gases, and even the development of plaque or calculus on teeth, or deposits on solar panels on Mars, among other examples.
This article is primarily devoted to the fouling of industrial heat exchangers, although the same theory is generally applicable to other varieties of fouling. In the cooling technology and other technical fields, a distinction is made between macro fouling and micro fouling. Of the two, micro fouling is the one which is usually more difficult to prevent and therefore more important.

Fouling , i.e., formation of a deposit layer (scale) on a solid surface, e.g., in a boiler; in particular, a kind of micro fouling as crystallization of salts
Deposition (chemistry), molecules settling out of a solution
Deposition (sediment), material (like sediment) being added to a landform
Precipitation (chemistry), the condensation of a solid from a solution during a chemical reaction​والشكر لكل من يساهم - ويضيف - مع من طرح الموضوع للإفادة ، شكراً للسيد ويندوز مان


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## محمد بعتى (17 نوفمبر 2013)

scale is a deposit of mineral salt consist maily os CaCo3 with solubility decrease when temperature increase


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## جمال بشر (15 فبراير 2015)

شكرا جزيلا


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