Liquid-solid separation problem
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Question: How to solve the liquid-solid separation problem? Material condition: the salt particles are very fine (turning into a powder after drying), and the viscosity of the liquid is 3.0 or higher. I’ve tried centrifugation, pressure filtration, and suction filtration, but none of these methods worked well. I hope experts can offer some guidance: handshake :handshake
Question: How to solve the liquid-solid separation problem? Material condition: the salt particles are very fine (turning into a powder after drying), and the viscosity of the liquid is 3.0 or higher. I’ve tried using a centrifuge, pressure filtration, and suction filtration, but none of these methods yielded good results. I hope experts can offer some guidance: handshake :handshake The liquid-to-solid ratio is 3:1; only 80% of the liquid can be obtained after filtration, and the filter cake has a high moisture content. What methods can be used to obtain a filtrate with a purity of over 95%, with the moisture content in the filter cake being less than 5%? This post was last edited by alkoxysilane on 2008-1-29 at 15:15.]
If the solid phase proportion is greater than that of the liquid phase, it is recommended to use a sedimentation centrifuge; for fine materials, centrifugal pressing should be considered
Is a sedimentation centrifuge a regular centrifuge?
When precipitating salts, optimize the process to produce larger particles, which makes separation easier; focusing solely on separation machinery may not yield satisfactory results.
If the material can be pumped, a diaphragm filter press can be used (such as domestic brands: Jingjin filter presses, Shandong Zhongda Beilait filter presses). German Klin high-pressure filters (Shanghai office), etc. It is best to have the prototype provided by the filter press manufacturer conduct a test in order to determine the effectiveness of the test, obtain relevant data, and facilitate model selection.
By using a pump for circulation, the brine sludge is filtered in a vibrating filter (plate and frame filter); the filtered brine sludge forms a filter cake on the filter screen, while the clear liquid proceeds to the next stage of processing. Our company uses equipment from Jueneng Company, and we also employ new-type scraper-type thin-film evaporators
It depends on the performance criteria that your product needs to meet; filter presses are generally used for this purpose, and there are no issues with sludge types
The effects are not good; in what specific ways is that manifested? What situation do you mainly want to improve? The original poster didn’t explain things clearly, making it impossible to judge.
I went to Jueneng to check, but nothing suited me; my materials are mainly solids that account for a large proportion of the weight.
Mainly, the moisture content of the filter cake is too high, and there is excessive loss of filtrate!
With filter pressing, firstly, it’s not possible to ensure airtightness – the material cannot come into contact with air. Additionally, the filter residue is difficult to remove, requiring frequent replacement of the filter plates
The key to solving the problem is to change the nature of the product. Improving the process and increasing the size of the salt crystals will yield twice the result with half the effort. If it’s an inorganic salt, it shouldn’t be difficult to produce in large quantities.
Salt is potassium chloride; do you have any good suggestions?
If it is potassium chloride from soft potash-magnesium fertilizers, separation is indeed difficult; centrifuges of the XR1200 type are widely used, and sedimentation screw discharge centrifuges are also employed. For cases where the crystals are large, HR two-stage piston-driven centrifuges can be used. In regions such as Sichuan, Hunan, and Shanxi, methods such as adding crystal seeds and slow cooling can be considered to increase crystal size
Freezing cooling is employed based on solubility. In the crystallizer process, the temperature of the cooling water can reach 5 degrees. We can continue to discuss the specific process
You can try a horizontal spiral discharge sedimentation centrifuge
I’m not very familiar with crystals. Could you explain it in more detail? In my case, what substances can be added to increase the size of salt particles?
One can try using a diaphragm box filter press; by applying pressure through the diaphragms, it is possible to further increase the solid content of the filter cake and reduce losses in the filtrate.
I’ve never used a diaphragm chamber filter press; I’ll go check it out in a bit. Thank you for your suggestion
The recommended diaphragm-press type plate and frame filter press applies additional compression from compressed air within the diaphragm after filtration by a conventional filter press, thereby significantly reducing the moisture content of the resulting filter cake.