Spray Dryer Absorber (SDA) is an air pollution control device used to control sulfur dioxide (SO2) and acid gas emissions in industrial processes. It is a type of dry scrubber that uses a combination of dry and wet processes to remove pollutants from exhaust gas streams.
In a spray dryer absorber, a fine mist of a chemical absorbent solution, such as lime or sodium carbonate, is sprayed into a high-temperature gas stream containing SO2 and other acid gases. The solution reacts with the acid gases and neutralizes them, forming solid particles that are collected in a baghouse or an electrostatic precipitator.
SDA is particularly effective in controlling emissions from coal-fired power plants and industrial boilers, which are significant sources of SO2 and acid gas emissions. It can achieve up to 98% removal efficiency for SO2, making it a popular choice for industries that need to comply with strict emissions regulations.
One of the advantages of SDA is its high reliability and low maintenance requirements. It can operate continuously without the need for frequent shutdowns or replacements of parts, which helps reduce downtime and operational costs. Additionally, SDA is a flexible technology that can be easily retrofitted into existing industrial processes.
However, SDA also has some limitations. It requires a significant amount of energy to heat the gas stream to the required temperature for efficient absorption, which can increase operating costs. The chemical absorbents used in SDA can also produce solid waste, which requires proper disposal.
SDA is a proven technology for controlling SO2 and acid gas emissions in industrial processes, particularly in the power generation and industrial boiler sectors. Its high efficiency, reliability, and flexibility make it a popular choice for industries that need to comply with strict emissions regulations while maintaining reliable and efficient operations.