Spray Dryer Absorber - The process has been applied to flue gas
cleaning at industrial plants.
More than 25 years ago, Niro innovated spray drying, and put it to work
absorbing the acid gases present in combustion gases. The Niro Spray Drying
Absorption - SDA - process has since its commercial recognition in the late
1970's been installed at more than 100 locations, primarily at coal-fired power
generating stations and at waste incinerators. Since the early 1980's, the
technology has found similar and widespread application in North America and in
Europe, just as the process has gained a strong foothold in the Far East during
the 1990's.
Today, the Niro SDA process has developed into a mature and
very versatile technology which has found application in combustion plants
ranging from small household waste incinerators to large coal-fired boilers.
The process has also been applied to flue gas cleaning at industrial plants.
This cleaning is often combined with a treatment of effluent or other waste
streams.
The Niro SDA process for flue gas cleaning is very simple as
it basically consists of the SDA module, a down-stream fabric filter, a reagent
preparation system and a product handling system.
Hot,
untreated flue gas, when introduced into a spray dryer absorption chamber
contacts a fine spray of reagent slurry. A significant part of the acidic
components in the flue gas are rapidly absorbed into the alkaline droplets,
water being evaporated simultaneously. Control of gas distribution, slurry flow
rate and droplet size ensure that the droplets are dried to a fine powder
before they touch the chamber walls of the spray dryer absorber.
A
portion of the dry product, consisting of fly ash and reaction product, drops
to the bottom of the absorption chamber and is discharged. The treated flue gas
flows to a particle separator, where the remaining suspended solids are
removed. Outlet gases from the particulate separator pass on to the stack by
means of an induced draft fan.
SPECIAL FEATURES:
- High acid gas removal efficiencies
- High plant availability
- Low capital cost
- Low power consumption
- Low operating and maintenance cost
- Low water consumption
- Utilize low water quality
NIRO SDA REFERENCES:
- Total plants built: 112
- Total number of absorbers: 230
- Total number of atomizers: 326
- Process installed at 10.400 MWe and 4.300 MWt power plant capacity
- Process installed at more than 100 incineration lines worldwide