How can I improve my FGD?

As regulations on FGD wastewater tighten, additional treatment is required. Often, this is chemically intense, and high cost. The best means to lower treatment costs is to reduce the volume of wastewater generated, usually by increasing internal recycle.

What is FGD wastewater?

Commonly used wet scrubber systems generates wastewater which contains high concentrations of ions with scaling potential, heavy metals, TSS and ammonia. This waste water stream needs to be treated before disposal and may even be re-used as process water.

How does an FGD scrubber work?

Wet FGD. The process of wet scrubbing typically utilizes an alkaline-based slurry of lime to scrub gases. A shower of lime slurry is then sprayed into a flue gas scrubber, where the SO2 is absorbed into the spray and becomes a wet calcium sulfite. One by-product of that sulfite is it can be converted to salable gypsum.

How can FGD be used to lower treatment costs?

The best means to lower treatment costs is to reduce the volume of wastewater generated, usually by increasing internal recycle. Internal recycle of FGD wastewater is limited by high chloride concentrations that inhibit sulfur dioxide absorption and can cause corrosion issues as chlorides are cycled up – this can be solved by the solution below:

When does FGD water need to be purged?

FGD water is recycled internally and then purged out of the system when chloride concentrations exceed a set level. High chloride concentrations inhibit SO 2 absorption from the flue gas and create corrosion concerns with wetted equipment. Chloride blowdown levels range with operations from 10,000 mg/L to as high as 30,000 mg/L.

How does flue gas desulfurization ( FGD ) work?

FGD water is recycled internally and then purged out of the system when chloride concentrations exceed a set level. High chloride concentrations inhibit SO 2 absorption from the flue gas and create corrosion concerns with wetted equipment.

What should chloride blowdown levels be in FGD?

Chloride blowdown levels range with operations from 10,000 mg/L to as high as 30,000 mg/L. Most FGD installations already include some wastewater treatment, typically referred to as ‘triple box’, wherein heavy metals and fluorides are removed via moderate pH (~pH 9) precipitation combined with polymer and coagulation, followed by a filter press.