Venturi Scrubber Design Online
| Parameter | Typical Range | Remarks | |-----------|---------------|---------| | Throat velocity | 50–120 m/s | Lower for sticky dust, higher for submicron | | L/G ratio | 0.5–2.5 L/m³ | Higher for hydrophilic particles | | Throat length | 0.3–1.5 m | Longer increases efficiency but ΔP rises | | ΔP | 5–25 kPa | Industrial median: 12 kPa | | Cut diameter (d50) | 0.5–2 µm | Achievable with v_t > 80 m/s | | Pressure recovery | 50–70% | Depends on diffuser angle |
The Diverging SectionIn the final section, the duct diameter increases again. This slows the gas down and allows the liquid droplets, now containing the captured pollutants, to coalesce and grow larger. This deceleration helps recover some of the pressure energy lost in the throat before the stream enters a separator. Critical Design Parameters venturi scrubber design
For each particle size fraction (e.g., 0.1, 0.5, 1, 2, 5 µm). Include Cunningham correction for dp < 1 µm. | Parameter | Typical Range | Remarks |
Venturi Scrubber is frequently the premier choice. But a Venturi scrubber isn't just a pipe with water sprayed into it. Its performance relies on precise, physics-based design. This post dives into the key components, design principles, and engineering considerations for designing an effective Venturi system. What is a Venturi Scrubber? A Venturi scrubber is a wet cleaning device that uses the "Venturi effect" to clean gas streams. By forcing air through a constricted "throat," the gas velocity increases dramatically, breaking scrubbing liquid (usually water) into tiny droplets. These droplets collide with and capture particulates, which are then separated from the clean air in a downstream cyclonic separator. Core Design Principles & Structure A robust Venturi scrubber design includes three main stages: Converging Section: The duct narrows, accelerating the gas velocity. Throat Section: The narrowest point where scrubbing liquid is injected. This is the heart of the scrubber where atomization and maximum gas-liquid contact occur. Diverging Section: The duct widens, allowing the mixture to slow down, allowing the liquid droplets (now containing particulates) to coalesce. 1. The Throat Velocity (The Key Driver) Throat velocity is the most crucial design variable. High-energy Venturi scrubbers operate at very high velocities (often 100-400 ft/s or more) to maximize particle collision and agglomeration. Too Low: Insufficient atomization, resulting in poor removal efficiency. Too High: Excessive pressure drop (higher energy costs). 2. Pressure Drop ( Δ Critical Design Parameters For each particle size fraction
High-grade stainless steel is a standard choice for general applications. For highly acidic environments, designers often turn to fiberglass reinforced plastic (FRP) or specialized alloys like Hastelloy. In cases where the gas is highly abrasive, such as in cement or mining plants, the throat section may be lined with silicon carbide or ceramic tiles to prevent erosion. Advantages of the Venturi Design
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