Centrifuge installation issues

It’s “quite” large, which can easily lead to catalyst loss.

The verticality of the cyclone separator’s assembly has a significant impact on the recovery of catalysts when the unit is put into operation. According to the requirements of SH3504, after the assembly and welding of the cyclone separator, the allowable deviation in its verticality is 5 mm.

It has a certain impact; during installation, make sure the cyclone unit is as vertical as possible, and that the material legs are also vertically aligned. But I believe that the requirements specified in the standards are a bit too strict; everyone knows that in these two types of devices, the temperature is high, so what happens as a result of thermal expansion? Only the Great Sage knows.

When installing the centrifuge, it is necessary to ensure its verticality. The requirements for installing the feed legs are not as strict, but it is essential that the bottom of these feed legs penetrate into the dense-phase bed or that wing valves be installed; otherwise, catalyst loss will occur.

A centrifuge is used to separate catalysts by means of centrifugal force; as is known, there are horizontal three-stage centrifuges, which consist of multiple smaller centrifuges inside. Therefore, the centrifuge cylinder does not need to be installed vertically, but the middle section and the cone section must be concentric, which is under the control of the manufacturer. The ash hopper does not have to be concentric with the centrifuge. The support legs can be angled and not installed vertically. However, the flap valve must be installed vertically, as the sealing of its valve plate relies on gravity. The centrifuge should be installed as vertically as possible to ensure even stress distribution and avoid uneven stress on the welds when the device is in operation at high temperatures. In a hot state, the centrifuge is in a form that cannot be seen; however, when a large number of centrifuges are together, they should not shake much. Otherwise it would have broken long ago. But if the tension rods of the leg are not welded firmly, the leg will break off; there are photos of this on the forum.

Yes, this issue deserves sufficient attention, because if the installation quality is poor, it can lead to catalyst loss. The problem of catalyst loss is a key factor that affects the long-term operation of catalytic devices, and the quality of the separator’s installation is also a very important aspect

The standard requirement for the verticality of a cyclone separator’s installation is less than 5 mm, but this is difficult to achieve in practice. During installation, we aim to keep the deviation within 10 mm. In fact, as long as the verticality deviation is not too large, it has no impact on the cyclone’s performance. What’s important is to consider how any deviation in the separator’s structure might affect the angle of the flap valve when it is in operation. The flap valve and the pipe section extending about 1000 mm above it must be installed with proper verticality; otherwise, due to the high expansion coefficient of 0Cr18Ni9 material when heated, the installation angle of the flap valve may change, which in turn can affect the cyclone’s efficiency. The straight sections of the leg are equipped with fixing bands, which also requires that the leg be vertical; otherwise, the expansion of the leg when it is hot will be affected. In my opinion, the verticality of the leg should be maintained within 10 mm.