Each plate provides a horizontal footprint projection calculated by its geometric area multiplied by the cosine of its angle.
Re=ρf⋅vmean⋅Rhμcap R e equals the fraction with numerator rho sub f center dot v sub m e a n end-sub center dot cap R sub h and denominator mu end-fraction Rhcap R sub h
cause sludge to accumulate on the plates, leading to severe fouling. Angles steeper than 60∘60 raised to the composed with power reduce the effective horizontal settling area. Typically ranges from
( A_proj = \fracQSOR ) (Q = flow rate in m³/h; SOR in m³/m²·h) lamella clarifier design calculation pdf downloadl better
Asingle=L⋅W⋅cos(θ)cap A sub s i n g l e end-sub equals cap L center dot cap W center dot cosine open paren theta close paren
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N=145.291.5≈97 platescap N equals 145.29 over 1.5 end-fraction is approximately equal to 97 plates Typically ranges from ( A_proj = \fracQSOR )
Divide the total required effective surface area by the projected area of a single plate to find the total number of channels needed (
Spreads incoming flow uniformly across the plate width, often using deflector plates or perforated walls to reduce turbulence.
Plates can be easily retrofitted into existing square or rectangular tanks to expand treatment capacity. 2. Core Engineering Formulas and Variables Core Engineering Formulas and Variables Atotal=Qv0cap A sub
Atotal=Qv0cap A sub t o t a l end-sub equals the fraction with numerator cap Q and denominator v sub 0 end-fraction Atotalcap A sub t o t a l end-sub = Total effective settling area ( m2m squared = Design flow rate ( = Surface overflow rate ( Step 3.2: Calculate the Effective Settling Area per Plate ( Apcap A sub p
▲ Clarified Effluent Out │ ┌───┴───────────────────┐ │ ││ ││ ││ ││ │ ◄── Effluent Launders (V-Notch Weirs) │ / / / / / / / / │ │ / / / / / / / / │ ◄── Inclined Lamella Plates (45° - 60°) │/ / / / / / / / │ │ │ ◄──┼─────────────────────────┼── Raw Water Influent In │ │ │ │ │ ▼ ▼ │ │ ╲ ╱ │ │ ╲ ╱ │ ◄── Sludge Hopper (Conical/Pyramidal) └───────▒▒▒▒▒▒▒▒▒─────────┘ ▼ Sludge Discharge
Plate thickness, spacing, total plate count, width, length, and angle.
Feed water must enter evenly across the entire width of the plate pack. Uneven distribution creates preferential flow paths (channeling), causing localized high velocities that disrupt settling.
Here are some common formulas used in lamella clarifier design calculations: