Problems with static mixers
Thread Content
I have two types of materials that need to be mixed and reacted in a static mixer; uneven mixing can easily lead to side reactions, and these side reactions release heat. I have two sets of these mixers; recently, one of them has given normal yields while the other has lower yields. In the mixer with lower yields, the temperature near the inlet is higher than that at the outlet (10 degrees higher than in the other set), whereas the temperature in the mixer with normal yields is more consistent throughout. The mixer is cylindrical; one material enters axially while the other enters radially, with the radial feed pipe being 200 mm away from the inlet end of the mixer. The two sets of mixers are homemade and have the same dimensions. However, the axial feed tube is inserted by drilling a small tube, so there may be variations in the position and number of holes. I would like to ask fellow sailors what the reason for this situation is. Is there any issue with the structure of the mixer?
As the flow rate of one of the materials decreased, the mixing temperature in one of the mixers increased; it is suspected that a side reaction is occurring. I would like to ask whether, in the case of static mixers, changes in flow rate can lead to such poor mixing performance Also, in the less optimal setup, the mixer goes through a 90-degree turn directly; is this a reasonable installation? But it was used for many years without this issue occurring; please help analyze it. I will definitely earn more points. 1# chenshsi
The depth of insertion of the axial tubule (or, in other words, the distance between the insertion end and the radial tube) has a significant impact on the mixing effect. 2# chenshsi
The two mixers were tested and no difference was found; the measurements were identical. It’s best to check the reasons for installation on site. If the above reasons are ruled out, then the issues with the flow and pressure measuring devices as well as the temperature control devices of the two sets of equipment need to be checked. If none of the above issues exist, it is best to check for differences in the operations and carefully examine any detailed problems.
The two sets of mixers are identical in terms of dimensions; the possible differences lie in the number and location of holes in the insertion tubes. Additionally, one set of mixers has an outlet that bends 90 degrees immediately. Both sets of mixers use material from the same storage tank, but the temperature of the mixture at the outlet of the mixer with an immediate 90-degree bend is 9–10 degrees higher than the temperature of the material at the inlet, and in some cases this difference can reach 20 degrees. The yield will also decrease significantly. It is said that the equipment has been in this condition for several years, but the concentration of one of the materials used in the past was 25% lower than it is now; in other words, the flow rate of that material has decreased by 25%. Does everyone think that this could lead to uneven mixing and the occurrence of side reactions? 4# yanzhg