ReACT™ (Regenerative Activated Coke Technology) is an advanced multipollutant technology that achieves simultaneous capture of SOx, NOx and mercury in one vessel.
The process was first developed in the 1970s in Germany, was subsequently advanced and commercialized in Japan where ReACT™ has been implemented at three large scale coal-fired power plants and at several steel mill and refinery applications:
- The J-Power 2 x 600 MW Isogo plant is the world’s lowest emissions coal-fired power plant.
- EPRI demonstration testing at Valmy station yielded results confirming the Isogo operation.
Hamon Research Cottrell offers ReACT™ under a license agreement from J-Power Entech.
Typical Performance at J-Power Isogo (since 2002):
|Pollutants||Emissions Permit||Operating Results|
|Efficiency||Inlet Concentration||Outlet Concentration|
|SOx||10 ppm (0.025 lb/MMbtu)||>98%||<410ppm
|NOx||13 ppm (0.02 lb/MMbtu)||10% to 50%||<20ppm
|Particulate||5 mg/Nm3 (0.004 lb/MMbtu)||>95%
(w/ backend ESP)
Three Stage Process
1) Adsorption - In the adsorber, flue gas and ammonia pass through a slowly moving bed of activated coke. The activated coke adsorbs SOx and mercury at high efficiency and reduces NOx as a co-benefit.
Activated Coke (AC) is produced from coal and activated by steam. It has high mechanical strength against abrasion and crushing and high specific surface area for adsorption.
2) Regeneration - AC with adsorbed SOx and mercury is conveyed to the regenerator. Here, sulfuric acid or ammonium salts in the AC are thermally desorbed and decomposed to form a sulfur-rich gas steam for by-product recovery by thermal desorption.
After desorption the AC is cooled and passed through a vibrating screen to remove undersized particles. Replacement AC is added to the system, and the regenerated AC returns to the adsorber for use.
3) By-product recovery - The sulfur-rich gas from the regenerator is converted into a marketable sulfuric acid.