After the new RO membrane was installed, the water production volume was very low, and the pressure difference for the concentrated water inlet was only 1 kilogram
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After the new RO membrane was installed, the water production volume was very low, at only about 60% of the designed flow rate. Moreover, the pressure difference for the concentrated water stream was only 1 kilogram, while the inlet pressure was 10 kilograms. Please offer some advice
Contact the manufacturer in advance. Check from the installation perspective
A concentrate pressure of 0.9 MPa is already quite high; it is recommended to check the details related to the membrane installation, such as whether the pipes have been cleaned properly
Check whether there have been any changes in the quality of the incoming water compared to the design values; if not, it means the performance of the membrane does not meet the requirements
Check the inlet pressure – what is the setting for the high-pressure pump pressure switch?
I am a membrane tube with 4 membranes; there are two membrane tubes connected together
There are two sets of membranes; the first set works very well, while the second set performs poorly. The membranes are installed randomly
May I ask about the pressure of the feed water pump, the outlet pressure of the high-pressure pump, the inlet pressure of stage 1, the inlet pressure of stage 2, and the outlet pressure of the concentrated water? Also, which company manufactures the membranes? There’s also the current inflow volume, output volume, and conductivity of the inlet and outlet water
This post was last edited by I am Wind0 on 2016-10-10 at 15:06. The outlet pressure of the high-pressure pump is 10 bar; there is only one stage in the system. The pressure of the produced water is 1 bar, while the pressure of the concentrated water is 9 bar. Dow membranes are used, with a water production volume of 7.2 tons and a concentrated water volume of 3 tons. The conductivity of the inlet water is 40, while that of the outlet water is around 2.0
Bro, your system has two membrane tubes connected in series, with each membrane tube having 4 membranes. It is recommended to use a 211 arrangement, which would be better. As you mentioned, with 7.2% for the produced water and 3% for the concentrated water, the production rate is 72% and the desalination rate is 95%. This is actually sufficient; there are no major issues with the system. You said the water production pressure is 1 kilogram; that’s quite high backpressure. Is the water tank too tall? Pressure buildup is something to be avoided in reverse osmosis; failing to eliminate backpressure will have negative effects on future operation, and I think this is the real problem.