| 摘要 |
The process for purifying active carbon used in pressure filters for condensate treatment, especially in the chemical, petrochemical and papermaking industries, involves () a first phase of filling the filter with demineralised water, continuously circulating a 2 wt.% hydrochloric acid solution at 40-95 deg C through the active carbon until the hydrometric value has stabilised (preferably about 10 h), discharging the hydrochloric acid solution from the filter and rinsing the filter and recirculation circuit with 5-10 volumes of demineralised water per volume of active carbon at 90 deg C; and a second phase of continuously circulating a 2 wt.% caustic soda solution at 90-95 deg C through the active carbon until the silica concentration has stabilised, emptying the filter, rinsing with 4-10 volumes of demineralised water per volume of active carbon at 90 deg C and open circuit rinsing while checking the pH, silica content and hydrometric value, before reusing the filter for treating condensates. Also claimed is the apparatus for carrying out the above process. |
