Dry flue gas cleaning
ANDRITZ dry flue gas cleaning systems meet the requirements for complying with the world’s strictest emissions legislation, the desire for low consumption of additives, the need for minimal residues, and the installation simplicity of a compact design.
ANDRITZ dry flue gas cleaning systems are well proven one-step cleaning solutions in a very compact design. They are equally suited to be used downstream of coal and oil-fired boilers, as well as biomass, RDF, or domestic and industrial thermal waste treatment plants.
ANDRITZ' dry flue gas cleaning technologies are based on two main applications
- TurboSorp is the ideal solution for flue gas cleaning systems in biomass plants, RDF-fired boilers, or Energy-from-Waste plants and other industrial applications.
- Turbo CDS is the right choice for flue gas cleaning downstream of oil or coal-fired boilers.
Our dry flue gas cleaning processes are based on well-proven circulating fluidized bed technology. The flue gas flows through a turboreactor from the bottom to the top and then enters a downstream particulate control device, which can be either a fabric filter or an electrostatic precipitator. Fly ash from incineration and fresh additives are dosed into the turboreactor, while a large part of the solid material from the reactor is fed back to the fluidized bed as recirculate. Water is also injected to lower the flue gas temperature and achieve higher separation performance.
If needed, activated carbon serves to provide excellent heavy metal and dioxin removal. As a result of advanced process management with regard to the operational temperature, solids recirculation, and the dosed additives, material consumption and the quantities of residue are kept to a minimum. The end product of the process is a dry, powdery residue which – depending on its composition – can be landfilled or used as filler (e.g. road construction) after stabilization.
Low investment and maintenance cost
TurboSorp and Turbo CDS systems are noteworthy for their compact designs. This allows for easier and lower cost installation in a plant. Fluidized bed technology does not employ rotating or wear parts, reducing the initial investment cost and the on-going maintenance costs. Due to the simplicity of the design of the system components, high levels of availability are typically achieved.
In certain cases, especially for smaller plants and for optimized investments, a dry sorption process based on lime or sodium bicarbonate is an interesting alternative to CFB-based flue gas cleaning technology. The process features a reactor, where the dry powdered additive is injected and mixed with the flue gas, and a downstream fabric filter.
Sodium bicarbonate for efficiency and low residue levels
The sodium bicarbonate process is used wherever residue quantities must be kept as small as possible. Due to the very high reactivity of sodium bicarbonate, only a small amount of it is required. The process is virtually independent of temperature and maximizes energy recovery.
Key features of the ANDRITZ dry flue gas cleaning system
- Proven technology with excellent references
- Removal of all pollutants in one step (dust, SO2, SO3, HCl, HF, dioxines, furanes, PCBs, heavy metals)
- Compact design, easy retrofitting
- Low maintenance costs, simple aggregates
- Operation above dew point, no corrosion
- Low sorbent consumption due to recirculation
- High separation efficiency and low emissions