Precautions for alternating steam and cooling water into the jacket of the reactor

This kind of operation is very common. If the temperature difference has no effect on the kettle (some glass lined kettles require that the internal and external temperature differences should not be greater than 90 degrees), as long as the operation is good, air hammer will not occur. The specific operations are as follows:; 1. Steam heating: close the jacket drain valve at the bottom of the bus and open the drain valve; Close the jacket vent valve; Open jacket steam inlet valve. 2. Stop heating: close jacket steam inlet valve; Close the drain valve at the bottom of the bus; Open the bottom jacket drain valve; Open the jacket vent valve again. (Wait for about one minute to completely drain the steam in the jacket) 3. Water cooling: first close the jacket vent valve, close the jacket drain valve, open the working water outlet valve on the kettle, and then open the working water inlet valve on the bottom jacket. Start cooling. 4. Cool to the target temperature and drain the water in the jacket: first close the water inlet valve and water outlet valve, then open the jacket drain valve at the bottom of the bus, open the jacket vent valve, and wait for the water in the jacket to be completely drained (the waiting time depends on the jacket capacity). This loop operates in this way.

Recently, two jacketed reaction kettles have to be installed. I have been thinking about this problem

If coils cannot be added to the reaction kettle, it is recommended that the reaction kettle be designed with two sets of spiral jackets, one for steam heating and the other for cooling water

You can add a heat exchanger (cooling) to the self circulation pipeline of the reactor. Whether it is vertical or horizontal depends on your working conditions and environmental realities

1. The switching of steam, circulating water and ice salt water is common in the fine chemical industry, and it can be switched after adding compressed air on the pipe bank and blowing it clean. 2. The heat transfer oil can be switched by using a cold and hot oil system, and the equipment overpressure caused by oil water mixing must be avoided. 2. The heat transfer oil must be used for heating and circulating water cooling, so it is necessary to design the jacket and inner coil at the same time

This problem can be solved by introducing compressed air or nitrogen into the jacket: after the cooling water is supplied, dry the cooling water pressure in the jacket with compressed air with lower pressure, and then inject steam. If necessary, compressed air or nitrogen shall also be supplied after steam supply.

After doing this, it is easy to leak the weld between the jacket and the tank body, and the temperature of the jacket needs to be lowered slightly.

If only external jacket is used, drain outlet shall be installed at the lowest point to drain water and steam before water supply. If possible, add an inner coil in the kettle, with steam flowing through the inner coil and water flowing through the jacket. Water hammer can be avoided. The latter method is more suitable for oil and water shared equipment.

If the jacket is heated by steam, the cooling water must be clean. If there is more mud, it will be difficult to heat. The position of the drain pipe mouth should be low to drain the water. Drain at the lower part of the steam pipe, warm the pipe before lowering the water carrying capacity and passing steam, and use a small amount of steam to slightly heat the jacket.

Why not add a coil? It's better to walk separately

In addition to the measures provided by Qing Chengjun, it is recommended to equip air blowing line on the jacket, and blow the cooling water before switching steam, and then supply steam.

First of all, ask the landlord, what is your reactor used for the device, and the process flow of the reactor in the device system? It seems that the operation of the reactor you are going to enter will be very difficult, and the production time of the materials to be reacted in the reactor may be slow

For your staged cold and heat exchange, you can consider kettle splitting reaction. Make a supporting hot reaction kettle, low reaction kettle, hot reaction kettle,,, and change these cold and heat exchanges into the transfer operation between kettles, which can better control the temperature of the hot reaction kettle and save energy consumption. At the same time, it will improve your production efficiency~save the cold and heat exchange time~

The same is true of our process, just for discussion. I think the steam pressure should be well controlled, and then the front row should be heated. Try to control the temperature by controlling the water

Purge and steam slowly. It's an old craft anyway. Such sudden cold and hot, operation is troublesome, potential safety hazards, equipment life, and inward leakage accidents are easy to occur. It is suggested that the reaction of different steps should be carried out in different kettles, and the containers should be switched by transferring materials.

Operation is troublesome, automatic control is difficult, and operation errors are easy to occur. If the cost is good, it is recommended to apply ethylene glycol hot oil.

The building owner must be able to add coils, which is of course the best. It may be limited by production conditions. There is no way but to use this old method. In this case, compressed air or nitrogen can be used when switching. It is easy to damage the reactor if you use this method for a long time.

How can such operation be required? Is it possible to use warm water to control temperature?

Are there any requirements for heating temperature, cooling temperature and time range of control temperature?

I also thought of looking forward to the expert's answer to this question! Can the heat transfer oil and cold water be switched in the jacket?