All Models of Blocking
Filtration proceeds according to number of widely recognized mechanisms, which have their origins in early filtration studies (Grace, 1956), Comprising (Fig.2.10):
- Completely blocking
- Standard blocking
- Intermediate blocking
- Cake filtration
Physical and Chemical Cleaning
The main impact of the operating flux is on the period between cleaning, which may be by physical or chemical means, and usually both. In MBRs, physical cleaning is normally achieved either by backwashing (reversing the flow) and relaxation (we suggest 7-minutes working 1-minute stop).
MBR Membrane Cleaning Method:
| Working setting /Relaxation | Interval Working, 7minutes working 1-minute stop. With air bubbles continuing. | |
| Air Vibration Cleaning Method | Aeration Vibration | 0.15—0.2 Nm3 /m². Hour |
| Backwash by clean water | Frequency | 5 minutes/ Every 120—300 minutes |
| Time | 5minutes | |
| Cleaning flow rate | Doubles of output flow rate/ Back flushing around 30 LMH | |
| Clean water | Output water or clean water with cartridge filter | |
| Backwash by Chemical [ Maintenance cleans] CEB Cleaning | Frequency | l 1 time per week for Sodium hypochlorite (NaOCL) l 1 time every two weeks for Citric acid |
| Time | 0.5 hour (Dosing time 8 minutes, soaking 20 minutes, clean water flush 2 minutes) | |
| Chemicals | l 200～500ppm of Sodium hypochlorite <NaOCL>； | |
| Chemical Cleaning Method [ Recovery cleans, offline cleans] | Frequency | Every 3—6 months /time, or flow rate low than 80% of designed flow flux. |
| Time | 1 day | |
| Clean water with chemical | Output water or city water with cartridge filter filtration, add chemicals. | |
| Cleaning Method | Immerse the MBR Modular with Vibrating in the MBR Tank or chemical clean water tank. | |
| Chemical | l Sodium hypochlorite <Naclo>： 2000ppm | |
| Steps | 1. Pump the activated sludge to the aerobic tank, and discharge all the dead sludge. 2. Disassembly the MBR Modules from Frame skid if the Membrane completely blocked or have too much sludge between hollow fibers. 3. Use the Spray gun (the one for car wash or fire-fighting workable) flush on and between surface of hollow fibers. 4. Fix the MBR membrane to the Frame skid. 5. Add the Clean water with Chemical(NaOCl with 2000mg/L), the PH Around 11 (add some caustic soda adjust the PH) 6. The MBR Modular completely immersed in the liquid, and with Aeration 6 hours and discharge the wastewater. 7. Add the Clean water with Chemical 1％Citric acid < C6H8O7>, the PH Around 2; The MBR Modular completely immersed in the liquid, and with Aeration 6 hours 8. Add clean water flush the MBR modules. Done | |
Photo as your reference:
Hinada is a professional manufacturer of MBR Membranes & MBR System; we have a professional and skilled water treatment engineer’s team with years experience, we always do our best to offer quality service and products and promptly response.
