Benefits of Amended Silicates over Activated Carbon
Amended Silicates for Mercury Control have many benefits over activated carbon, as shown in the tables below.
Challenges of Activated Carbon
| Activated Carbon (PAC & BPAC) for Hg Control |
| Only Adsorbs Mercury - It also Desorbs Mercury - All Hg will eventually leach |
| Mercury Must be Oxidized by a Halogen (Bromine, Chromine, or Iodine) First |
| Limited to Low Sorbent Utilizations - i.e., Typically < 0.2% |
| FLAMMABLE and EXPLOSIVE - Silo Fires have been a problem in the U.S |
| Often Requires Halogen Addition to Coal to Help Oxidize the Mercury - Corrosion!!! |
| Contaminates the Fly Ash so that it Cannot be Used in Concrete - Difficult to Treat |
| PAC & BPAC are Poisoned by SO3 / H2SO4 - Often Requiring Hydrate Injection |
| Hydrate/Trona Injection Capture Halides Which increases BPAC Rate 3-4 Times |
| Combined with Halogen (Br or I) Injection, Contaminates Waste Water |
| BPAC Causes Severe Corrosion of Storage Silos, Including Structural Damage |
While Amended Silicates are not hindered by any of those challenges listed above for activated carbon, Amended Silicates do have many additional benefits. Check out the benefits in the table below:
Benefits of Amended Silicates
| Amended Silicates for Hg Control |
| Non Carbon, mineral based products |
| Relatively captures both Hg0 and Hg2+ |
| Stabilizes all metals in the fly ash - reduces leaching |
| NOT FLAMMABLE NOT CORROSIVE |
| No Halogens in the Products - Does NOT Need Halogens |
| Preserves fly ash sales - Eliminates liability of landfills |
| Compatible with Hydrate/Trona Injection |
| Tolerant to SO3 / H2SO4 |
| Small Carbon Footprint |