Flue Gas Desulphurisation (FGD)

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FGD Gas Dust and Flow Monitoring: In industrial processes such as the combustion of coal, oil, waste, and metal ore production, significant quantities of sulfur dioxide (SO2) are generated. This compound poses risks to human health and contributes to environmental degradation.


To mitigate these impacts, Flue Gas Desulphurisation (FGD) technologies have been developed to remove SO2 from flue gases before their release into the atmosphere. These advancements are crucial in reducing emissions from coal-fired power plants worldwide, which are either currently equipped with SO2 scrubbers or in the process of retrofitting them to comply with stringent environmental standards.


The core principle behind most SO2 control methods involves spraying an alkali sorbent into the flue gas. This sorbent reacts with acidic SO2, as well as with other acidic gases like hydrogen chloride (HCl) and hydrogen fluoride (HF), neutralizing them and rendering them less harmful to the environment.


The resulting reaction products are managed using various methods depending on the type of FGD system employed. In Dry FGD systems, they are captured in dust filters. Wet FGD systems use gypsum slurry in a sump to precipitate and remove pollutants. Alternatively, Sea Water FGD systems treat and dispose of the reaction products safely into the sea after appropriate treatment.


Limestone, lime, and hydrated lime are the most commonly used sorbents in the desulphurisation process due to their effectiveness in neutralizing acidic components of flue gases. These materials play a critical role in reducing SO2 emissions and improving air quality, contributing to healthier environments and sustainable industrial practices.

What we do

In order to control FDG systems, these processes require monitoring throughout. CODEL offer a range of products that can monitor both input and output gases, flow & dust emissions reliably and accurately using the very latest technology

Wet limestone FDG with open spray tower
Semi-Dry FGD, circulating dry scrubber

Suitable Products

The DCEM2100 is a dual-pass transmissometer configured for the continuous measurement of opacity and dust concentration in flue gases.

Opacity / Dust

CODEL’s unique flow monitors measure the velocity of stack gases using a highly accurate time of flight measurement that is derived from a cross correlation analysis of the infra-red emissions of the turbulent gas.

Gas Flow

The GCEM40 analyser is an in-situ device which is cost-effective, low maintenance and designed both for process control and emissions monitoring.

CO, NOx, SO2, HCl, CH4, CO2 & H2O

The GCEM40E hot extractive multi-channel gas analyser is CODEL’s industry-proven continuous emissions monitor for difficult applications

CO, NOx, SO2, HCl, CH4, CO2 & H2O

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