Technology Overview
The illustrative design layout of FBC.
Fluidized bed crystallization (FBC) uses silica sand as carriers and crystallization seeds to recover metal salts or inorganic ions from wastewater in crystalline forms. Properly controlled upward flow maintains pellets bed, seed and adhesively grown crystals, in a fluidized state. Control of chemical reagent addition provides appropriate super- saturation for crystal formation. Pellets are discharged when the size is grown up to 1 to 2 mm in diameter and settled by gravity at the bottom.
Applications & Benefits
- Effectively removing inorganic ions from wastewater.
- Reducing sludge production by 75%, and hence lowering the cost of disposal.
- Recovering valuable resources in crystalline form, and hence making profit from residue treatment, as well as complying with the environmental mandate code.
Fluorine contained wastewater, conventionally treated by precipitation process, which generates large amount of sludge, can be treated by FBC. Other wastewater treatment such as water softening and heavy metal removal also can be successfully carried out by FBC reactors.
ITRI's FBC technology has been successfully applied to many cases, including seven cases for fluoride recovery (five in semiconductor industry, two in TFT-LCD industry); two cases for ammonium removal (TFT-LCD); two cases for calcium removal (one in water softening and one in petrochemical wastewater reuse); and one case for heavy metal removal (PCB industry) . In summary, the FBC has been successfully carried out and proven its capability for the following water treatments,
- Fluoride-containing wastewater.
- Arsenic-containing wastewater.
- Water softening.
- Phosphate/ammonium removal.
- Heavy metal removal from wastewater.
Full-scale applications of FBC.