What are the reasons for the low yield of brine produced by Kai Membrane?
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This post was last edited by sunjl1981 on 2013-1-6 at 22:23. What are the reasons for the low yield of brine produced by the membrane distillation process? How do you deal with this issue? # hcbbs
This post was last edited by TF123 on 2009-12-12 at 13:18. The moderator’s rating comment is not true; I have been wronged. Due to previous issues with sulfate removal, our brine system now produces only a very small amount of brine, enough to support low-load operation of a single electrolyzer. The KAI membrane supplier is helping to find a solution, but no solution has been determined yet. We ask all experienced users to analyze the reasons and help resolve this issue. :handshake
What is the filtration pressure? There’s also this thing. How many years have you been using your membranes? And why are you asking so many questions about saline? I’m in this shift too
Haha, you have more questions; you asked several times about just one of my questions. We already have many problems with saltwater. I wasn’t in this department before, and now I have to learn from scratch; please give me a lot of help. The filtration pressures reached 0.09, 0.1, and 0.085 MPa respectively ； I’ve been using it for almost four years, and this is the first time I’ve encountered this issue; it’s about to cause a shutdown of the entire system. Please help analyze it!
The surface of the removed membrane was adhered to by a sticky substance, and pickling was ineffective. It may be that the addition of an excess amount of barium ions from the clarification tank after removing sulfate ions caused barium sulfate to adhere to the system; it could also be that poor performance of the filter press led to barium sulfate entering the system. To facilitate sludge removal, a certain amount of flocculant, namely sodium acrylate, is added before filtration. The current hypothesis is that it is this substance that enters the system and causes stronger adhesion. If anyone knows, please help analyze it; it’s urgent. :handshake
1. The Kay membrane filter needs to be pickled as soon as possible. I’ve encountered this situation; we washed it over a dozen times in one day, and each unit had to be pickled every 3 hours. The air flotation tank definitely performs poorly and causes turbidity; identify the cause and address it as soon as possible
With such high pressure, the water volume must be low. Sodium polyacrylate is an organic flocculant, and KAI membranes are most sensitive to organic substances. . . The problem is quite serious. Take a sample of that sticky substance and analyze it to determine what solvent can be used to remove it. Try organic solvents such as alcohol. I’m not sure what condition our membranes will be in after 4 years of use; they should probably need to be replaced by then, as their designed lifespan is only 3 years.
Sorry, I’m a newbie and didn’t see what was said on floor 5
I’m not very familiar with Kay membranes. Since they are made of tetrafluoroethylene, if they can withstand concentrated sulfuric acid or nitric acid, I wonder whether they could be used to carbonize organic substances in the presence of concentrated acids and to dissolve inorganic substances
Based on what the poster said, it can be inferred that the issue is not related to the Kay membrane filter; the problem lies mainly with the flotation tank and the clarification tank. In terms of the clarification tank, a large amount of sodium polyacrylate is added in order to obtain clean water, but this does not yield satisfactory results. The excess sodium polyacrylate, along with sediment particles, ends up in the subsequent processing stages. The mixing effect of air and water in the flotation tank is not optimal, and the excess sodium polyacrylate and sediment particles are not completely removed before reaching the Kay membrane. This results in a sticky layer forming on the surface of the membrane, blocking its channels – and this blockage cannot be removed through backwashing; the only solution is to disassemble the filter for repair. Therefore, in future production, one should not strive to achieve high standards in a certain process by adding large amounts of additives, thereby exceeding the capacity limits of the equipment and achieving the opposite result.
Can we use ferric chloride as a flocculant and diluted sodium hypochlorite solution for foaming?