Page 273 - APPLIED PROCESS DESIGN FOR CHEMICAL AND PETROCHEMICAL PLANTS, Volume 1, 3rd Edition

Mechanical Separations 243

Decanter -

Light phase overflow

I I
Light phase
Drain interface
/ ,
for emulsion __ ,
J
Heavy phase

Light phase out

Figure 4-12. Gravity decanter basic dimensions. Adapted by permission, Schweitzer, P.A., McGraw-Hill Book Co. (1979) [32].

Vessel heads bend or tangent
lines
15'+2
z
15'
Partial baffle at interface clear
Inlet top by 0.3D and be 1'-6"
t ,.r·O"in/llnj vertical height only 4-trial outlet nozzles, one at
estimated interface
Min. 0.340 to 0.450
I=' Interface

0
0.550 to (")
Dispersion Band= 10%0
0.660 = c
II
7.34 ft
2" drain hole flush with floor
Tee on feed inlet
Velocity= 0.5-1'sec
Baffle, solid except top 6 .. with
Perforated underflow baffle, 1 .. pert. holes on 1.5<t_ 11
holes area approx = outlet areas Water phase out. Perforated
with min. W' holes, tee Baffle height at estimated baffle, set min. 6" off bottom,
Interface = 2-4 .. from bottom, 2 to 3 times nozzle diameter
sealed at bottom
Figure 4-13. Decanter for Example 4-1.