Hello Mohsen,This is a ...
Published by Soloman Prince, Plant General Manager at FAPCO
Hello Mohsen,
This is a question answered with multiple questions:
- What is the position of this membrane in the pressure vessel? Usually scaling issues show up first in last membrane of vessel
- Recommend checking the composition of this deposits
- Is this happening for all membranes or just those in certain location? Lead or rear side?
- What is the increase in a) salt passage, b) differential pressure c) feed pressure (or reduction in flow if feed pressure constant). These three factors together give a very good clue as to the possible type of the problem.
In general, having weight increase at this early stage is sign of very bad problems. Judging from the picture, scaling problem.
Either something solid already present in the feed (like clay for example) or scaling are the explanations that could explain such rapid increase.
check if there was an interruption in the dosing of antiscalant - it is recommended to check the obvious first.
Weight of membranes after put in operation should be weight of the new membrane + slight increase because of the wetting.
It can be easily checked by soaking a new membrane in water, then letting it drain for 30 minutes and weight.
My feeling is that should only be half a kilo more than a bagged new membrane.Based on your answers to the above I can suggest some thing.