The standard configuration of the cooling PP reactor is 10MPA, that is, 100 atmospheric pressure. The cooling PP reactor of 20MPA or 30MPA can be customized. As for the pressure of the reactor, it should be selected according to the experimental conditions. The bigger the worse. Each cooling PP reactor has a safety valve and alarm control system, so safety can not be considered. On the other hand, the greater the external pressure is, the thicker the kettle wall is, the heavier the pressure is, the larger the corresponding pressure measuring range is, and the more inaccurate the manometer's marketability is. If the pressure is large, and it needs to be read accurately, it is recommended to buy a digital manometer. However, the digital manometer has a large dial and an unattractive appearance, and the cost is higher than the pointer manometer. Then, let's understand the matters needing attention in the process of cooling the PP reactor together!
What should I pay attention to when heating and cooling the PP reactor?
During the use of cooling PP reactor, the heating and cooling operation should be careful. It is forbidden to conduct fast cooling and fast heating operation on the reactor to avoid cracking or damage of the reactor tank due to high temperature.
After the operation, it can be cooled by water (heating reaction) or air cooling. The tight thread seal of the needle valve can be achieved by turning the needle valve slightly to make the cover close contact. Do not use excessive force to avoid damaging the sealing surface.
After the reaction, first cool down, release the high-pressure gas in the kettle, reduce the pressure to normal pressure, loosen symmetrically and evenly, and remove the bolts. Pay special attention to the protection of the sealing surface when removing the cover.
At the end of each operation, please remove the residue from the kettle body and lid. All sealing surfaces of the cooling PP reactor need to be cleaned and dried frequently. It is not allowed to clean with hard objects or soft objects with rough surface.
When disassembling the agitator for cleaning, the reactor heat transfer jacket in the form of cooling PP reactor jacket heat exchange is generally made of ordinary carbon steel, which is a simple and convenient container that forms a sealed space outside the reactor barrel. The jacket is equipped with inlet and outlet of water vapor, cooling water or other heating and cooling media. When the heating medium is water vapor, the inlet pipe is close to the upper end of the jacket, and the condensate is discharged from the bottom; When the heat transfer medium is liquid, the inlet pipe is set at the bottom, and the liquid enters from the bottom and flows out from the top, so that the heat transfer medium fills the whole casing space.
For large vessels, in order to obtain better heat transfer effect, spiral guide plates are set in the jacket space, which can reduce the flow area of the fluid in the jacket, improve the flow speed of the fluid, and avoid short circuit, but the structure is complex. When the diameter of the kettle is large or the pressure of the thermal medium used is high, the semi-circular spiral pipe or spiral angle steel welded structure is often used to replace the jacketed structure. This can not only increase the flow rate of the heat transfer medium and improve the heat transfer effect, but also increase the strength and rigidity of the external pressure resistance of the reactor. In order to improve the heat transfer efficiency, the upper end of the casing is provided with a non-condensable gas outlet. The spacing between the jacket and the cylinder adopts different values according to the nominal diameter of the vessel, generally 25~100mm. The height of the jacket is determined by the heat transfer area, which is determined by the process requirements. However, please note that the jacket height is generally not lower than the liquid feed height. In order to ensure sufficient heat transfer, it is necessary to be about 50-100mm higher than the liquid level in the vessel. With the increase of the volume of the reaction equipment, the heat transfer problem suddenly appears. The jacket is not enough. The reactor is often equipped with additional heat transfer plates. The heat transfer plate can not only increase the heat transfer area, eliminate the heat, but also strengthen the mixing effect, and play the role of destroying the vortex control flow pattern. There are many structural types, such as D-shaped baffle, finger plate, sleeve type, annular tube, elliptical tube plate, etc. The heat transfer coefficient of baffle is much larger than that of sleeve. Among them, the cooling water flow rate is large, the pipe wall is thin, and the material supply coefficient on the baffle surface is also large, so the overall heat transfer coefficient is large. However, when using the heat transfer baffle, it is necessary to consider the structure and cleaning issues, and the baffle should be placed below the liquid level. Because the gas-liquid interface is easy to scale.
General process specification for mechanical processing of cooling PP reactor:
1. When operating the reaction kettle, carefully check the instructions in the drawings and process documents, keep the process documents clean and complete, process the parts in strict accordance with the design drawings (process procedures and technical requirements), and do not change at will.
2. The operator shall check the borrowed measuring tools according to the process requirements, and contact the shift leader in time if there is any doubt about whether the tools meet the process and use requirements.
3. Before processing, the operator should check or spot check the blank of the reaction equipment. After preliminary processing, check the relevant dimensions of the process and confirm whether the margin meets the process requirements.
4. The first article inspection of the workpiece, if not specified by the process, should be carried out in free state, and should not be pressed on the fixture or machine tool workbench or other pressure on it for inspection. After changing the tool, it also needs to be inspected.
5. For the continuous processing process or process, the operator can carry out self-inspection according to the process and process, and entrust the quality inspector to assist in the inspection if necessary to avoid batch scrapping.