How to Inspect MBR in Operation?

Compared with traditional treatment methods, the Membrane Bioreactor (MBR) has the advantages of better treatment effect and less land occupation due to its advantage technology. In recent years, it has developed rapidly in the field of sewage treatment in the world. In the process of daily use, it is necessary to do maintenance to ensure the normal and stable operation of the membrane bioprocessor, extend the service life of the MBR membrane module, and reduce the operating cost of the membrane bioreactor to realize more value.

1. Aeration Situation

Regularly check whether the amount of aeration air meets the standard amount, and check whether the aeration is uniform. Once the aeration is found to have obvious unevenness or the aeration volume does not meet the specified value during the inspection, necessary measures shall be taken in time to avoid serious situations.

2. Transmembrane Pressure Difference

Regularly check the changes in the transmembrane pressure difference, if the transmembrane pressure difference suddenly shows an upward trend, it indicates that the membrane is blocked, which is generally caused by abnormal aeration state or deterioration of sludge. Once this happens, perform proper chemical cleaning of the membrane module immediately, and then check whether the transmembrane pressure difference is normal. It is generally required to install a negative pressure gauge at a suitable position between the water outlet of the MBR membrane and the inlet of the self-priming pump to record the transmembrane pressure difference.

3. The Smell and Color of Activated Sludge

The normal activated sludge smell is unpleasant and its color is generally dark brown and the sludge has agglomeration characteristics. If the appearance of the sludge and its smell are abnormal, check the data of MLSS, PH, water temperature, DO, sludge viscosity, BOD load and other data in time to determine the cause and solve it in time.

4. MLSS Value and Sludge Settling Performance

If the normal effluent index can not be reached, the MLSS range needs to be adjusted. When the MLSS value is lower than the normal value, timely take reasonable measures such as putting in seed sludge or stopping the discharge of sludge. When the MLSS value is higher than the normal value, take necessary measures such as increasing the sludge discharge volume to the retention tank to restore the MLSS value to normal. The sedimentation performance of the sludge has a great influence on the MBR membrane. If the sedimentation performance is not good, it is easy to cause the membrane flow to decrease. At this time, measures must be taken to improve the sedimentation performance of the activated sludge.

5. PH Value

The PH value in the normal membrane bioreactor is in the range of 6-8. If the value can not be reached in actual use, an appropriate amount of acidic or alkaline substances can be added to the sewage treatment to adjust the PH value is within a reasonable range and to ensure the normal operation of the membrane bioreactor (MBR). When adding alkaline substances, we recommend not to add lime water as much as possible, which will easily cause the inorganic salt of the membrane to scale.

6. Water Temperature and Water Level

The normal water temperature in the Membrane Bioreactor (MBR) should be between 15~40℃. If the water temperature rises or drops abnormally during actual use, cooling or heat preservation measure should be taken in time to ensure the normal operation of the system. The MBR water level must be higher than the MBR membrane stent. If the water level is lower than the MBR membrane stent, it will affect the normal operation of MBR.

7. DO Value

The normal DO value of the membrane bioreactor should be above 1mg/l. When this value is not met, the maximum aeration rate is not exceeded. If the dissolved oxygen is too low, it will affect the metabolic rate of the microbes inside the flocs and the biochemical treatment effect. Therefore, appropriate measures such as adjusting aeration conditions must be taken in time to ensure the normal DO value.

In the daily use of the membrane bioreactor (MBR membrane), the above aspects must be inspected in time, and the operation status must be recorded. When problems are found, correct and effective measures shall be taken to adjust in time to ensure the stable and efficient operation of the membrane bioreactor and the effluent quality to meet the requirements.