Flue Gas
De-Sulfurization (FGD)

Flue Gas De-Sulfurization (FGD)

Your trusted partner in advanced Flue Gas Desulfurization (FGD) solutions. At RIECO, we harness the power of innovation, engineering excellence, and rigorous research to deliver world-class Flue Gas Desulfurization (FGD) systems. We’re mitigating harmful emissions such as Sulfur Dioxide (SO2), Nitrogen Oxides (NOx), Mercury, Dioxins, and Furans, all while crafting a future that harmonizes industry and environment.

With nearly half a century's experience in the air pollution control equipment and systems business, we have a legacy of creating eco-friendly industrial solutions. Notably, RIECO pioneered the installation of the first lime based wet FGD in India in 1998.

As a prominent flue gas desulfurization manufacturer, we grant advanced solutions for FGD (flue gas desulfurization). Through meticulous spray nozzles, we treat flue gases in the FGD wet limestone process. Aiming at emissions from burning fossil fuels and coal fired power stations, our system eliminates sulphur dioxide (SO2 emissions) and produces calcium-containing compounds, bestowing eco-friendly landscape.

Our high-performance FGD solutions are meticulously engineered to align with stringent norms from both local and central pollution control boards. At RIECO, we don't just aim for compliance; we inspire industries to spearhead the journey towards sustainable progression.


Wet Scrubbing (Limestone FGD) Systems
  • The most common type of FGD system.
  • Flue gas is passed through a spray of limestone slurry, which reacts with the SO2 to form gypsum, a useful byproduct.
  • Features -

    • High Efficiency: Capable of removing up to 95% or more of the SO2.
    • Byproduct Utilization: Produces gypsum which can be commercially sold for wallboard manufacturing, cement additive, etc.
    • Flexible: Can handle variable sulfur content in fuel.
Dry Scrubbing Systems
  • Lime or limestone in a powdered form is injected directly into the flue gas.
  • Reaction products are collected along with fly ash by the particulate control system.
  • Often used for smaller installations and where water usage is a concern.
  • Features -

    • Water Economy: Consumes less water compared to wet systems.
    • Compact: Generally, requires less space.
    • Ease of Retrofit: Can be easier to retrofit into existing plants due to its smaller footprint.
Dual Alkali Systems
  • Uses two alkaline substances: one to scrub the flue gas and another to regenerate the spent scrubbing liquid.
  • Effective in handling high-sulfur fuels.
  • Features -

    • Reduced Scaling: Reduced risk of scaling in the scrubber, as regeneration occurs outside the scrubbing loop.
    • Optimal for High-Sulfur Fuels: Capable of handling fuels with high sulfur content.
    • Less Corrosive: The system can be less corrosive than other methods.
Circulating Fluidized Bed (CFB) Scrubbers
  • Uses the principles of fluidization, with lime or limestone as the scrubbing medium.
  • Offers advantages in handling variable sulfur fuels and gives high removal efficiencies.
  • Features -

    • Fuel Flexibility: Can handle varying sulfur contents efficiently.
    • High Removal Rates: Comparable to wet systems in SO2 removal efficiency.
    • Temperature Tolerance: Can operate at elevated temperatures, potentially reducing energy costs.
Electrostatically Enhanced Systems:
  • Incorporate electrostatic precipitators to aid in the collection of particulates and enhance SO2 removal.
  • Often combined with other FGD systems for improved efficiency.
  • Features -

    • Improved Particulate Removal: Enhances the removal of particulate matter along with SO2.
    • Reduction in Equipment: Can combine functions, potentially reducing the need for separate equipment.
    • Improved Collection: Can improve the efficiency of downstream equipment.
Sorbent Injection Systems
  • Directly injects alkaline materials (sorbents) into the flue gas.
  • Suitable for applications that require moderate levels of SO2 removal or as a retrofit to existing systems.
  • Features -

    • Simplicity: Less complex compared to some other FGD systems.
    • Retrofit Friendly: Suitable for adding to existing systems for SO2 reduction enhancement.
    • Quick Implementation: Faster to install and commission than more complex systems.


Our expertise lies in designing, engineering, and supplying gas cleaning plants and FGDs for both wet and dry applications. Key features and benefits of our FGD systems are as follows:

  • Proven Technology: Our FGD systems employ technology from reputed companies in Europe and the USA, ensuring reliable and efficient operations.
  • Versatile Wet System: Depending on the situation, our wet system can be offered with various reagents like lime, limestone, sodium carbonate, and caustic soda.
  • Useful Byproducts: Our lime/limestone-based system produces useful byproducts like gypsum, promoting circular economy principles.
  • Specially Designed Spray Tower: Our spray towers minimize material build-up, ensuring low downtime for the plant.
  • Dry Injection System: This system can be used for direct furnace injection, or duct injection prior to a baghouse or Electrostatic Precipitator (ESP), depending on duty conditions.
  • Efficient Reactor Design: Our specially designed reactor, positioned upstream of the baghouse, facilitates efficient mass transfer and neutralization of SO2.
  • Dry System Reagents: Our dry system employs reagents such as sodium carbonate, lime, and activated carbon to absorb various contaminants, in addition to SO2.
  • Multistage FGD: We offer multistage FGD solutions based on the inlet conditions.
  • Proven Equipment Designs: Our designs and experience extend to key equipment required for an FGD such as baghouses, ESPs, wet scrubbers, and more.

With RIECO, you get a partner with proven industry experience, technological excellence, and a commitment to sustainable and efficient industrial operations.

Why Rieco?

As your global partner, we fully immerse ourselves
in your process challenges.
48 +
Years of Experience
40 +
6000 +
Successful Installations
300 +
Strong Team
5 +
Global Partnerships
Manufacturing Facilities
Global Presence
We’re there for you
West Indies
United Kingdom
Saudi Arabia
Sri Lanka
Feel free to ask us anything you have in mind,
we are happy to answer
Enquire Now
Back to Top
Enquire Now

Enquire Now