Sperta System
MBR Offline Cleaning I

How to Do Offline Chemical Cleaning For MBR Membranes

Table of Contents

When operating MBR for a long time, there exists an irreversible and polluted solid layer. Backwash and online cleaning methods may not work, and the TMP did not reduce. It is necessary to do offline chemical cleaning. Its flux can recover by offline chemical cleaning.

Step 1: Remove the suction tube and the aeration tube from the MBR module. Then take the MBR module out of the tank. 

Step 2: Use a nozzle to clean and remove the activated sludge attached to the surface of the fibers.

Step 3: Take the MBR elements out of the module and immerse the elements in a prescribed chemical solution tank. Stay for 6-12 hours.

Step 4: Take out the MBR element from the immersion cleaning tank and wash it thoroughly with water to remove the chemical solution. 

Step 5: Install the MBR on the MBR module after cleaning.

Step 6: Connect the aeration pipe and put the module in the tank. Stop the filtration, just let the aeration run for more than 30 minutes, and then start the filtration.

Step 7: Before discharging the chemical solution, reduce the sodium hypochlorite with sodium thiosulfate (Na2S2O3 NH2O), and then discharge.

Step 8: If there is a large amount of inorganic scale on the surface of the MBR after sodium hypochlorite washing, acid washing is also needed.

MBR Offline Cleaning I

The chemicals used in offline chemical cleaning are shown in the below chart.

Main pollutantDetergentUse ConditionsCleaning time
Metal oxide, calcium-containing scale0.5% Citric acid /
0.2% Hydrochloric acid
pH=24~8h
Fatty acids, proteins, polysaccharidesAlkali (0.5mol/L NaOH) and 200 mg/L oxidizing agentpH=104~8h
Bacteria, biomacromoleculeAlkali (0.1mol/L-0.5mol/L NaOH) and 200mg/L oxidizing agent /
Enzyme preparation, surfactant (0.1%-2%) /
1000-2000mg/L NaClO, 1%-3% Alkali
pH=104~8h
Kevin Chen

Kevin Chen

Hi, I'm the author of this post and have been in this field for over 5 years. If you have questions regarding the MBR membrane products or want to purchase the MBR membrane, please feel free to contact me by email. kevin@spertasystems.com

Like this article?

Share on Facebook
Share on Twitter
Share on Linkdin
Share on Pinterest

More to explorer

How to Calculate Carbon Source Dosage

How to Calculate Carbon Source Dosage?

Calculating the carbon source dosage in wastewater treatment is very important, aimed at supplementing the organic carbon needed for microbial growth and promoting biodegradation. Here are two different calculation methods:

Can MBR Membrane Bioreactor be Backwashed?

Can MBR Membrane Bioreactor be Backwashed?

MBR hollow fiber membrane is a kind of MBR membrane bioreactor, which can be backwashed. The following will tell you about the backwashing knowledge of hollow fiber MBR membranes.

Need MBR Membrane for your plants?
Get The Latest Updates

Subscribe To Our Newsletter

No spam, notifications only about new article updates regarding MBR membrane Technologies.

Sperta System

Ask For A Quick Quote

We will contact you within 6 hours, please pay attention to the email with the suffix “@spertasystems.com”.