| Backwash parameters |
Backwashing mode |
Air-water backwash |
| Design backwash frequency |
48 times/day |
| Scrubbing air pressure during backwashing |
≤150KPa |
| Backwash flux |
1~1.5 times of water production flux |
| Backwash gas flow |
8~12 Nm3/h (each) |
| Backwash operation mode |
30min per cycle |
| Maintenance cleaning |
Maintenance cleaning method |
Circulating flushing of low concentration citric acid or sodium hypochlorite solution |
| Maintenance cleaning time |
50min (including flushing time) |
| Citric acid frequency |
Once/1~3 days |
| Sodium hypochlorite frequency |
Once/1~3 days |
| Cleaning flow |
1~2m3/branch membrane module |
| Maintenance cleaning concentration |
300 ~ 500ppm |
| Restorative cleaning (chemical cleaning) |
Chemical cleaning method |
Alternating circulating flushing of citric acid solution and NaOH sodium hypochlorite solution |
| Chemical cleaning time |
90 ~ 180min |
| Pickling frequency |
Once/30~90 days/set (PH=2) |
| NaOH+sodium hypochlorite cleaning frequency |
Once/30~90 days/set （PH=10） |
| Circulating flow |
1~3m3/formwork assembly |
| Chemical cleaning concentration |
1000 ~ 3000ppm |
| Optimum temperature range of dosing cleaning solution |
20 ~ 30℃ |
