Flue gas desulfurization (FGD) wastewater treatment project

Project Overview:

The desulfurization wastewater is mainly the discharge water from the absorption tower in the process of the wet desulfurization of boiler flue (limestone/gypsum method) produced by the combustion of coal in power generation facilities.

In order to maintain the material balance in the slurry circulation system of the desulfurization device, to prevent the concentration of chlorine exceeding the specified value, and to ensure the quality of the gypsum, a certain amount of wastewater must be discharged from the system, which is mainly from the gypsum dehydration and cleaning system. The impurities contained in the wastewater mainly include suspended solids, supersaturated sulfites, sulfates and heavy metals, which are among the first type of pollutants that shall be strictly controlled by the requirements of national environmental standards. Desulfurization wastewater is one of the most difficult pollutants to treat in wastewater treatment in power plants.

The project’s challenges:

1. High concentration of calcium sulfate andcalcium sulfite

2. High suspended solids concentration

3. Unstable and intermittent desulfurization wastewater

4. High hardness and low alkalinity

Solution: Our Treatment Process

This was a transformation project. The previous treatment method was a physicochemical method. The heavy metals and suspended solids of the main pollutants in the desulfurization wastewater were precipitated by adding chemical agents. The sediment was separated by a clarifier. The effluent was discharged. The sludge was discharged through the plate frame machine, and then was transported out of the plant. This treatment process required the addition of a large amount of medicament, requiring a lot of space and making it very difficult to operate.

Our transformative treatment method: The sesalting part of the equipment is treated with DTRO system. The new system can achieve the treatment requirements of desulfurization wastewater, recycled waste liquid drainage from clean water neutralization pond, and recycled waste liquid in fine treatment neutralization pond.

The advantages of Jinzheng’s Treatment System:

1. Simple pretreatment

2. High recovery rate and low energy consumption

3. Low chemical operation costs

4. A long service life for the membrane and separately replaceable membrane disk

5. High system reliability, high effluent quality and stable separation performance

6. Small footprint, flexible and compact modular unit with high mobility