FGD Wastewater Treatment

FGD Wastewater

What is FGD Wastewater?

Coal-fired power plants produce sulfur dioxide (SO2) air pollution, which can be reduced by flue gas desulfurization (FGD) systems. FGD wastewater has a lot of calcium sulfate, as well as metals and chlorides. Cybertig can improve FGD water cycles by removing chlorides selectively, or eliminate FGD wastewater completely.

Sulfur dioxide (SO2) is a harmful gas that contributes to acid rain and respiratory problems. Coal-fired power plants are major sources of SO2 emissions, as coal contains sulfur impurities that are released when burned. To reduce SO2 pollution, power plants use flue gas desulfurization (FGD) systems, which spray a chemical solution into the exhaust gas to capture and remove the SO2 molecules. However, this process also generates a large amount of wastewater, which contains high levels of calcium sulfate (gypsum), metals (such as mercury, arsenic, and selenium), and chlorides (salt).

FGD wastewater poses a challenge for power plants, as it cannot be discharged directly to the environment without proper treatment. The wastewater can damage aquatic ecosystems, contaminate drinking water sources, and corrode pipes and equipment. Moreover, the wastewater is often saturated with gypsum, which makes it difficult to treat with conventional methods. Therefore, power plants need to find effective and economical ways to manage their FGD wastewater.

The treatment

Cybertig, a Turkish company that specializes in water treatment technologies, offers a range of solutions for FGD wastewater treatment. One of them is a novel system that can remove up to 90% of chlorides from FGD wastewater, using a membrane technology. This technology uses an electric field to separate and transport monovalent ions (such as sodium and chloride) across a membrane, while rejecting divalent ions (such as calcium and sulfate). By removing chlorides selectively, Cybertig can enable power plants to recycle most of their FGD wastewater internally, reducing the need for external disposal and freshwater intake.

Another solution that Cybertig offers is zero liquid discharge (ZLD), which means that no liquid waste is left after the treatment process. ZLD is achieved by using a combination of evaporation, crystallization, and solidification technologies to remove all the water and salts from the FGD wastewater, producing dry solids that can be reused or disposed of safely. ZLD is the most environmentally friendly option, as it eliminates any liquid discharge and minimizes the waste volume.

Different solutions

Cybertig can also provide other options for FGD wastewater treatment, such as:

Physicochemical methods: These methods use chemical reactions, precipitation, coagulation, flocculation, filtration, and adsorption to remove metals, sulfates, and other contaminants from the FGD wastewater.
Electrochemical methods: These methods use electrodes, electric currents, and electrolysis to remove metals, sulfates, and other contaminants from the FGD wastewater.
Biological methods: These methods use microorganisms, such as bacteria, fungi, and algae, to degrade or transform organic and inorganic contaminants in the FGD wastewater.
Spray drying methods: These methods use hot air to evaporate the water from the FGD wastewater, forming fine droplets that are then collected as dry powder.

Cybertig can select the best technologies to match the customer requirements, depending on the characteristics of the FGD wastewater, the environmental regulations, and the economic feasibility. Cybertig has the expertise and experience to provide customized and integrated solutions for FGD wastewater treatment.