Engineering application of internal circulation denitrification reactor for reverse osmosis concentrated water treatment

Abstract

Internal circulation（IC） denitrification reactor was designed on the basis of IC anaerobic reactor，and the engineering application was investigated for the reverse osmosis concentrated water treatment. The results showed that the IC denitrification reactor exhibited a rapid start and stable running. The effluent TN ranged from 1.89 mg/L to 14.0 mg/L with an average of 4.65 mg/L when the influent TN were from 18.7 mg/L to 39.0 mg/L with an average of 26.6 mg/L，which was lower than the required 15 mg/L by Standard B of Table1 in Comprehensive Wastewater Discharge Standards for the Yellow River Basin in Shanxi Province （DB 61/224-2018）. The effluent suspended solids mass concentration was lower with an average mass concentration of 18.6 mg/L，and the effluent COD of the subsequent recirculation biofilter was 35.4 mg/L，stably controlled below 50 mg/L，which showed a perfect comprehensive treatment effect. Moreover，the IC denitrification reactor had a small footprint，simple process，and a direct water treatment cost of 1.36 yuan/m3，which had significant economic benefits.

Keywords

• internal circulation
• denitrification reactor
• reverse osmosis concentrated water