Selection of filters for special requirements
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I’m currently working on a project involving intermediates that are produced from starting materials; these are intermediates subject to GMP regulations. The product is in liquid form and highly acidic. Material compatibility tests have been conducted, and it was found that even 316L stainless steel can be corroded by this substance. Other requirements for the filter are as follows: Filtration temperature: 90℃ ； The solid to be separated is activated carbon accounting for 5% of the product’s weight ； A 0.45μm sterilization filter is required after the activated carbon filter ； The batch size of the product is 1000 kg. In a situation like this, how should one choose a filter?
Due to its high acidity and 90-degree temperature, PP filter tanks are basically unsuitable, as they tend to deform and crack easily. We use titanium-lined filter presses here; filter cloths, filter paper, and filter bags are used inside to filter activated carbon
At such high temperatures and with strong acidity, titanium materials are not resistant to corrosion either; it is recommended to use enamel-coated filters or graphite-modified polypropylene filters (with a sufficiently large filtering area, as otherwise high pressure can cause deformation). The requirements for the filter cloth are also quite high; you can try using polypropylene filter cloth! ! !
Using a ceramic filter element will definitely work
Thank you all for your help. It seems that activated carbon filters are a good solution, but what about sterilization filters? Is there any suitable equipment available?
The difficulty in your problem lies in how to separate out the solids, which account for 5% of the total weight. Such a high solid content is better suited for filter presses or centrifugal separators, but neither type of equipment is resistant to corrosion, nor are there any temperature constraints.
A PES material is more suitable for .45 sterilization filters
Is it manufactured by a factory, or does it need to be custom-made? I’ve found a manufacturer that can carry out Halar spraying and can also meet our requirements.
The introductions from those upstairs were really simple! I’m new to this and don’t quite understand it! !
The impurity content is too high; plate and frame filtration or centrifugation are the only options. However, temperature and corrosion factors make these methods unsuitable. It is recommended to use large-scale basket filters lined with fluoropolymer for staged filtration. If cooling is not possible, PFA filter elements combined with fluoropolymer-lined filters must be used
I’d like to share my personal opinion: perhaps it would be worth considering the use of filters made of graphite or those with PTFE (PFA) linings, in terms of the filtering pores