The crux with the mist ( 3)

When designing an aerosol separator unit, a number of questions arise.

How many elements are required for a defined gas volume flow ?

How should the installation position be ?

Which arrangement pattern is chosen?

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As a rule of thumb the capacity of a standard demister element is approx. 1000 Nm3/h ?per m length of an element. An element with standard length of 120“ has an capacity of round about 3000 Nm3/h.

The pressure drop is depending linear with the gas volume flow. The (dP * V ) is the expense for the aerosol separation, also pressure drop costs some plant capacity.

From that point of view a comparision of total cost of ownership?is worth to be reviewed.Investment cost cover cost of elements , housing,construction etc.?combined with operation costs( pressure drop and loss of capacity.) over n years ( n typical 4 years) lead to an diagram like <diag1>

When energy costs are double as high the optimum shift towards more elements.<diag2>

Regarding the installation position the are 2 options: standing or hanging.<diag3>

Standing?arrangement has slightly lower invest cost ( only one drain ) compared with the hanging version with a drain at each element and an optional collector.

From operational view I personally prefer the hanging version. When removing used elements after some years It is much easier and safer than the standing version.

The next question ist the arrangment pattern of the elements. That task can be seen also as an mathematical optimization (packing ) problem ( circle within surrounding circle ). Such problems are solved since some decades.– Be inspired by looking at the www.packomania.com?homepage.

There You?can see the optimal solutions for a given numer of elements. <diag 4>

With such a solution You can arrange maximal numbers of elements in a given outer diamenter, or choose min. outer diameter for a given number of elements , this way minimizing the cost for the housing.

Note: the cost in € are some years old and not actual !

There is also a fundamental difference between investment cost and operation cost

Investment cost are created at the beginning of the life cycle , operation cost are running during lifetime, when the investment costs are forgotten.

Nowadays You can feel it.

#aerosol separation # sulfuric acid