Limestone wet scrubbing system for flue gas desulfurization

How does limestone wet scrubbing work?

When limestone is added to the flue gas, it reacts with the sulfur dioxide present to form calcium sulfite. The calcium sulfite is then converted to calcium sulfate by reaction with oxygen in the air. The calcium sulfate is then scrubbed from the flue gas by contact with water.

The benefits of limestone wet scrubbing

When limestone wet scrubbing is used for flue gas desulfurization, it can provide a number of benefits. For one, the process can achieve a high degree of sulfur removal efficiency. Additionally, limestone wet scrubbing can be used to control both particulate matter and acid gases. Finally, the process can help to minimize the release of mercury into the environment.

The disadvantages of limestone wet scrubbing

When limestone is used for wet scrubbing, it must be ground into a very fine powder so that it can react with the flue gas. This process requires a lot of energy and can produce large amounts of waste material. Additionally, the limestone slurry can become very acidic and corrosive, which can damage equipment. Finally, wet scrubbing systems are typically very expensive to operate and maintain.

How to build a limestone wet scrubber

A wet limestone scrubber is a type of air pollution control device that is used to remove sulfur dioxide (SO2) from exhaust gases. The SO2 removal process occurs when the exhaust gas contacts the surface of the wet limestone. As the gas flows over the surface of the limestone, the SO2 reacts with the water to form calcium sulfite (CaSO3). The calcium sulfite is then removed from the exhaust gas by a dust collector.

There are two types of wet limestone scrubbers: forced oxidation and natural oxidation. In a forced oxidation wet limestone scrubber, oxygen is injected into the scrubber to help promote the reaction between the SO2 and limestone. In a natural oxidation wet limestone scrubber, room air is used to provide the necessary oxygen for the reaction.

The following steps are involved in building a wet limestone scrubber:

1. Prepare an absorption solution by dissolving powdered or slurry-based lime in water.

2. Introduce the flue gas to be treated into the bottom of the absorption tower.

3. The flue gas rises through the tower and comes into contact with falling drops of absorption solution.

4. As the flue gas reacts with the absorption solution, SO2 is removed from the gas and forms calcium sulfite in solution.

5. The calcium sulfite-laden solution is collected at the bottom of the tower and sent to a waste treatment system where it is solidified and disposed of.

6. The treated flue gas is discharged from the top of the tower.

What is a limestone wet scrubbing system?

A limestone wet scrubbing system is a process used to remove sulfur dioxide (SO2) from flue gas. The system uses a slurry of limestone and water to absorb the SO2 from the flue gas. The slurry is then recirculated back to the scrubber where it absorbs more SO2.

How does it work?

The process of wet scrubbing with limestone is well-suited to flue gas desulfurization (FGD) because it can remove sulfur dioxide (SO2) from the exhaust of coal-fired power plants, as well as other industrial sources, while also providing a number of other benefits.

The basic process involves passing the flue gas through a spray of limestone slurry, which absorbs the SO2 in the gas. The limestone slurry is then passed through a series of separators where the SO2-laden water is separated from the clean limestone particles and can be further treated.

Wet scrubbing with limestone is an effective and widely-used FGD technology because it:

-Can achieve high removal efficiencies of SO2 (up to 99%)

-Is relatively low in cost

-Is flexible in terms of operating conditions and can be easily adapted to different types of flue gas streams

-Produces a wastewater stream that can be easily treated before being discharged

What are the benefits of using a limestone wet scrubbing system?

Wet scrubbing systems for flue gas desulfurization (FGD) using limestone as the reagent are well-proven and cost-effective. When compared to other FGD technologies, wet scrubbing systems offer certain advantages:

1. Low capital cost: Wet scrubbing systems are relatively straightforward and require less equipment than other FGD technologies. This results in a lower overall investment cost.

2. High removal efficiency: Wet scrubbing systems can achieve very high levels of SO2 removal, up to 99%. This is important for compliance with increasingly stringent emissions regulations.

3. Modularity: Wet scrubbing systems can be easily expanded or modified to meet changing needs. This flexibility is important as power plant operations and regulations evolve over time.

4. Low operating costs: The reagents used in wet scrubbing (limestone and water) are readily available and inexpensive. Additionally, wet scrubbing systems have low power requirements, resulting in lower overall operating costs.

How to choose the right limestone wet scrubbing system for your needs

There are a few key things to keep in mind when choosing a limestone wet scrubbing system for flue gas desulfurization (FGD). The first is the sulfur dioxide (SO2) removal efficiency that you need. There are a variety of different types of FGD systems, and each has its own removal efficiency.

The second factor to consider is the size of the system. The larger the system, the more expensive it will be. However, you may need a larger system if you have a higher SO2 emissions rate.

Finally, you need to consider the maintenance requirements of the system. Some systems require more maintenance than others. Make sure you understand the maintenance requirements before making your purchase.

Conclusion

The limestone wet scrubbing system is an effective way to remove sulfur dioxide from flue gas. It can be used in a variety of settings, including power plants and other industrial facilities. The system works by passing the flue gas through a chamber containing limestone slurry. The sulfur dioxide reacts with the limestone, and the resulting solution is then passed through a filter to remove any solid particles.