Selection of valves for solid powders
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Hello everyone, I’d like to ask for your advice. For a reactor with a capacity of 6000, we need to use pipes with a diameter of 150 to feed in powder material. After feeding the material, it’s necessary to close the valve and create a vacuum. What type of valve would be suitable for this purpose? The material must be resistant to acids and alkalis, and able to withstand temperatures of 180 degrees.
Use ball valves; any with a soft seal should work
Is the powder transported by pneumatic conveying? Or automatic feeding? Why is acid and alkali resistance needed? What is the negative pressure during vacuuming?
There are too few conditional parameters: feeding method, particle size, viscosity, pressure
I have coaxial valves at home that can be used to control powders; they offer two-way vacuum functionality. You can message me privately
First of all, thank you all. The material is in a form similar to caustic soda, available in powder and slab forms; it isn’t very sticky, but it still becomes sticky when exposed to moisture. The vacuum level required is below 5 millimeters.
What is a solid powder? Is it hard? Use a soft seal for those that are not very tall; use a hard seal for taller ones! But what is the vacuum level below 5 mm? Hard-sealed vacuum valves are very difficult to manufacture! It seems this valve needs to be replaced frequently! Ball valves with soft seals can be used in vacuum conditions, and the temperature requirements can also be met by RPTFE/PEEK. However, the powder is too hard, which causes the valve seats to wear out quickly, requiring frequent replacement! Moisture-induced stickiness can also damage the valve seat!
This depends on the hardness of the powder; the material should be chosen based on its resistance to acids and alkalis. Soft-seal or triple-eccentric butterfly valves can be used. But the valve used as a liner doesn’t seem suitable for vacuum conditions – is it resistant to acids and alkalis? Is there more liquid?
The poster should clarify whether the material is fed into the tank using gas or by manual pouring If it is only manual material pouring, a quick-release manhole is completely sufficient; there is no need to use a valve. I have previously been involved in the transportation of fine particles and materials at around 400 degrees Celsius, using two ball valves for that purpose. The effect is okay.
A hard-sealed ball valve can solve this issue, as it enables two-way sealing!
Apart from the unclear requirement regarding acid and alkali resistance, all other conditions are suitable for our company’s coaxial valves.