Multi-Pollutant Synergistic Control | Semi-Dry Desulfurization (SDA)

🌊 Volumetric & Thermal Capacity

• 📉 Gas Volume: 10,000 to 2,300,000 m3/h
• 🌡️ Max Gas Temp: Up to 260 °C
• 🌫️ Inlet Dust Density: 1 to 2000 mg/Nm3
• ⚖️ Casing Pressure: -6000 to +6000 Pa

🎯 Purification Performance

• ✅ Desulfurization Efficiency: > 95%
• ✅ Outlet Emission: < 35 mg/Nm3
• ✅ Operating Resistance: 800 to 1500 Pa
• ✅ Droplet Size: Ultra-fine 60 μm

🏭 Target Heavy Industries

• ⚡ Utility Boilers: Medium & Small Units
• 🔥 Waste Incineration: Multi-acid gas removal
• ⚗️ Industrial Kilns: High dust & variable loads
• 💧 Zero Liquid Discharge: Arid/Strict environments

The SDA Working Principle

The core principle relies on the explosive contact between an atomized alkaline slurry (usually Calcium Hydroxide) and high-temperature flue gas. This achieves rapid evaporation and drying, executing a gas-liquid-solid three-phase acid-base neutralization in milliseconds.

Because the water evaporates entirely before the droplets hit the reactor wall, no wastewater is generated. All reaction products are solid powders, subsequently captured by a downstream bag filter.

Core Chemical Reactions:

• Slurry Prep: CaO + H2O → Ca(OH)2
• Main Desulfurization: SO2 + Ca(OH)2 → CaSO3 / CaSO4 + H2O
• SO3 Removal (Plume Elimination): Ca(OH)2 + SO3 + H2O → CaSO4·2H2O↓
• Halogen Control: 2HCl + Ca(OH)2 → CaCl2 + 2H2O
  2HF + Ca(OH)2 → CaF2 + 2H2O

Internal Component Architecture

The BLSSDA series utilizes highly advanced fluid dynamics to ensure perfect droplet-to-gas contact:

• Central Gas Distributor: Located at the absorber roof. Flue gas enters via upper and lower paths through outlet guide vanes, creating a counterclockwise swirl. This ensures thorough mixing and prevents “wall-wetting”. A baffle prevents dust deposition.
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• Rotary Atomizer (Patented): The absolute core of the SDA process. High-speed centrifugal force shears the lime slurry into extremely fine 60 μm droplets, multiplying the specific surface area exponentially for rapid SO2 absorption.
• Pneumatic Ash Conveying System: Captured fly ash and unreacted calcium are pneumatically conveyed from the bag filter back to the Circulating Ash Silo. This ash is remixed with water to form fresh slurry.

30% – 50% Reagent Savings

Unreacted lime in the dried product forms nuclei inside each new slurry droplet during recirculation. New absorbent continuously deposits on these nuclei, drastically increasing the lime surface area. This recirculation slashes fresh reagent consumption by up to 50%.

Zero Liquid Discharge (ZLD)

By utilizing the sensible heat of the flue gas to evaporate the slurry carrier water, the system produces a completely dry powder byproduct. This eliminates the need for multi-million dollar wastewater treatment plants required by wet scrubbers.

No Tail-End Corrosion

Because the gas exits the absorber and baghouse well above the acid dew point (typically > 75°C), there is absolutely no condensation of sulfuric acid in the downstream ductwork or stack. Expensive anti-corrosion linings (like glass flake or titanium) are entirely unnecessary.

The Wastewater and Plume Crisis of Wet FGD

Operating traditional wet scrubbers introduces massive compliance headaches. Not only do they produce toxic heavy-metal laden wastewater that is increasingly illegal to discharge, but they also cool the gas below the dew point. This results in highly visible, highly regulated “blue plumes” composed of fine SO3 aerosols. Semi-Dry SDA chemically binds these aerosols into dry solid salts, rendering your stack exhaust completely invisible and dry.

The Low Efficiency of Simple Dry Injection

Many plants attempt basic dry sorbent injection (DSI) to avoid wet scrubbers, only to find they cannot consistently hit the new < 35mg/Nm3 mandates because dry powder reaction kinetics are too slow. SDA solves this by introducing water *as a vehicle* for the reaction. The liquid phase provides the optimal environment for instantaneous mass transfer, achieving wet-scrubber efficiencies (>95%) while still delivering a dry end-product.

Waste-to-Energy & Incinerators

Municipal and hazardous waste incineration generates extreme spikes of HCl, HF, and SO2. The SDA process excels here, providing rapid, simultaneous neutralization of all acid gases before the baghouse.

Medium/Small Utility Boilers

For coal or biomass boilers where massive limestone-gypsum wet scrubbers are economically unviable or where the site lacks the massive footprint required for wastewater infrastructure.

Steel & Coking

Ideal for coking exhaust and specific sintering processes. Keeping the gas temperature elevated after desulfurization perfectly sets up the exhaust for downstream SCR denitrification.

For over 20 years, Ever-power has been the trusted engineering authority in heavy industrial air purification. Designing an SDA system requires mastering precision atomization, thermodynamics, and pneumatic conveying. It is a science we have perfected.

• ✔️ Full Value-Chain Integration: We are true EPC contractors. We deliver Process Engineering ➔ Manufacturing ➔ Turnkey Site Installation ➔ Intelligent Commissioning.
• ✔️ Patented Atomization Technology: We utilize top-tier proprietary rotary atomizers (integrating Niro technology) that reliably produce the critical 60 μm droplets necessary for instantaneous evaporation without wall-wetting.
• ✔️ Proven by Industry Giants: Our bespoke SDA systems successfully safeguard the compliance of massive conglomerates, including Tongchuan Shengwei, Shanshui Group, and major municipal waste facilities.

The Cost of Obsolete Wet Systems

• Wastewater Nightmare: Wet scrubbers produce highly toxic wastewater. Building and operating a Zero Liquid Discharge (ZLD) treatment facility can cost millions annually.
• Corrosion Maintenance: Acid dew point condensation ruthlessly destroys ID fans, ductwork, and stacks, causing catastrophic replacement costs and extended plant downtime.

The Ever-power Upgrade ROI

• Zero Wastewater OPEX: No slurry dewatering, no vacuum filters, and no wastewater treatment. The operational and maintenance savings alone justify the CapEx rapidly.
• 30-50% Reagent Reduction: Our automated pneumatic ash conveying system recirculates unreacted lime back into the slurry. This maximizes chemical utilization, slashing your daily quicklime (CaO) procurement costs by up to half.

🇨🇳 Shenyang Municipal WTE (China)

Application: Waste-to-Energy Incinerator Exhaust

Challenge: Lethal spikes of HCl and HF gases causing severe corrosion, coupled with strict zero-liquid-discharge municipal limits.

Solution: Retrofitted with the Ever-power SDA system. The atomized lime instantly neutralized the acid spikes. The dry ash was safely captured by the bag filter, ensuring 100% dry compliance.

🇮🇳 Tata Sub-Processing Unit (India)

Application: Medium-Scale Coking Plant

Challenge: Required simultaneous removal of SO2 without dropping the gas temperature too low, to allow downstream SCR denitrification to operate efficiently.

Solution: Installed the BLSSDA Series. Achieved SO2 < 25 mg/Nm3. The semi-dry process maintained gas exit temperatures above 140°C, perfectly protecting and feeding the SCR catalyst.

🇧🇷 Sao Paulo Bio-Refinery (Brazil)

Application: Large Biomass Boiler

Challenge: High ambient humidity and space constraints made building a wet scrubber settling pond impossible.

Solution: The compact SDA reactor was installed directly upstream of their existing baghouse. The pneumatic ash recirculation reduced their lime consumption by 40%, boosting overall plant profitability.

🇩🇪 Bavaria Heavy Industries (Germany)

Application: High-Temperature Industrial Kiln

Challenge: Previous pure-dry injection struggled with low reactivity and failed to meet the new EU <35mg/Nm3 SO2 limits.

Solution: Switched to Ever-power’s Semi-Dry system. The introduction of the liquid phase (atomized slurry) exponentially boosted the reaction kinetics. Guaranteed compliance was achieved immediately.