To design this system in Excel, you must solve for three primary architectural metrics: Column Diameter (
[Workbook Structure] ├── Tab 1: Cover & Instructions (Version control, scope) ├── Tab 2: Design Dashboard (User inputs, primary outputs, safety factors) ├── Tab 3: Calculations Engine (Formulas, unit conversions, iterations) └── Tab 4: Engineering Data (Packing factors, chemical properties, steam tables)
Step-by-step cells calculating gas density, flooding velocity, design velocity, and column diameter.
Key Inputs
You can build custom formulas tailored to specific chemical reactions or waste streams 1. scrubber design calculation excel best
NTU=ln(yinyout)×(11−youtyin) (Simplified for dilute systems)cap N cap T cap U equals l n open paren the fraction with numerator y sub i n end-sub and denominator y sub o u t end-sub end-fraction close paren cross open paren the fraction with numerator 1 and denominator 1 minus the fraction with numerator y sub o u t end-sub and denominator y sub i n end-sub end-fraction end-fraction close paren (Simplified for dilute systems)
, this tool is the gold standard for estimating capital and annual operating costs based on waste gas composition and pollutant properties. Spray Tower Rating Spreadsheet : Developed by experts like Meloni Marco
NTU=ln(yin−yin*yout−yout*)NTU equals l n open paren the fraction with numerator y sub i n end-sub minus y sub i n end-sub raised to the * power and denominator y sub o u t end-sub minus y sub o u t end-sub raised to the * power end-fraction close paren
Usually water or a chemical reagent solution (e.g., NaOHcap N a cap O cap H for acid gases). Liquid Density ( ρlrho sub l ) and Viscosity ( μlmu sub l ): Needed for hydraulics and pressure drop equations. Performance Target Removal Efficiency ( To design this system in Excel, you must
Designing a scrubber—whether it's a wet scrubber for industrial gas cleaning or a simpler air scrubber
): Used to determine the hydrodynamic behavior and pressure drop across the packing. Defines the equilibrium curve for gas absorption. Packing Characteristics
-axis): Use standard generalized pressure drop correlation (GPDC) equations to solve for
The choice of packing directly affects column sizing. Packing materials come in random shapes (e.g., Pall Rings, Raschig Rings, Saddles) or structured corrugated sheets. Every packing style has a specific , measured in ft-1f t to the negative 1 power m-1m to the negative 1 power Fpcap F sub p provides more surface area but increases pressure drop. Fpcap F sub p allows higher gas velocities but requires a taller column. Spray Tower Rating Spreadsheet : Developed by experts
A basic sheet is good. The sheet includes these power features:
The most critical step in packed tower design is ensuring the gas velocity is high enough for efficiency but not so high that it causes flooding. Usually 50-70% of flooding velocity 2. Tower Diameter ( Dtcap D sub t ): Calculated using the formula C. Mass Transfer and Height Calculation
Finding the templates is the key to automating repetitive sizing steps, verifying flooding limits, and predicting pressure drops. Why Use Excel for Scrubber Design?
HTU considers the packing-specific mass transfer coefficients ( kGk sub cap G kLk sub cap L