Page 97 - Separation process engineering

Horizontal flash drums (Figure 2-15) are used for large flow rates because additional disengagement area
is formed by making the column longer and horizontal columns are cheaper than vertical ones.

(2-69a)

Figure 2-15. Horizontal flash drum

If we arbitrarily choose h/D = constant C and solve for diameter D, we obtain

(2-69b)

If the ideal gas law is valid, the molar density and the mass density ρv are,

(2-69c)

Equation (2-69b) becomes

(2-69d)

The value of u is found from Eq. (2-64) with (Blackwell, 1984)

(2-69e)
where K is determined from Eq. (2-65).
vertical
The typical range for h/D is from 3 to 5. Horizontal drums are particularly useful when large liquid surge