What should be noted when using a microreactor?

　　What are the structural features of a microreactor?

　　I. Work Pressure

　　Microreactors operate at high working pressures. The pressure inside the reactor is generated by chemical reactions or rising temperatures, resulting in significant pressure fluctuations and occasional operational instability. Sudden pressure spikes can sometimes exceed the normal pressure by several times; therefore, most reactors are classified as pressure vessels.

　　II. Operating Temperature

　　Small reactors operate at relatively high temperatures. Generally, chemical reactions proceed under specific temperature conditions; therefore, the reactor must be capable of withstanding both pressure and temperature. The common methods for achieving high temperatures are as follows:

　　1. Water heating.

　　It can be used when the required temperature is not high, and its heating system comes in two types: open and sealed.

　　2. Steam heating.

　　When the heating temperature is below 100°C, steam at a pressure lower than atmospheric pressure can be used for heating. In the temperature range of 100°C to 180°C, saturated steam is recommended; at higher temperatures, superheated steam under high pressure can be used.

　　3. Heating with other media

　　If the process requires operation at high temperatures or necessitates avoiding high-pressure heating systems, mineral oil (275–300), a benzene-ether mixture (boiling point 258), molten salts (140–540), and liquid lead (melting point) can be used.

　　4. Electric heating.

　　Wrap the resistance wire around a temporary insulator positioned a few distances away from the reactor vessel’s insulation layer or the reactor itself, thereby creating a tiny air gap between the resistance wire and the reactor body.

　　If you want to achieve high temperatures using the first three methods, you’ll need to add clamps to the floating body. This is because the temperature range can be quite large, causing thermal expansion and contraction in both the float’s clamps and its outer casing, which in turn generates differential thermal stress. When using electric heating, the equipment is lightweight and easy to control in terms of temperature. It doesn’t require pumps, furnaces, chimneys, or other complex facilities, making operation straightforward and low-risk with relatively low costs. However, the operational costs are higher than those of other heating methods, and the thermal efficiency is below 85%. This method is best suited for applications where the heating temperature is below 400°C and electricity prices are low.

　　IV. Hybrid Structure

　　Microreactors are typically used for chemical reactions. To ensure that the reaction proceeds uniformly and rapidly, thereby improving work efficiency, corresponding stirring devices are usually installed in the reaction chamber, which in turn pose challenges related to dynamic sealing and leak prevention for the drive shaft.

　　V. Small Reactor Operations

　　Most microreactors operate in a batch mode, and sometimes, to ensure product quality, they need to be cleaned after each run. The top of the reactor is equipped with a quick-access inspection port and a handhole, facilitating sampling, volume measurement, reaction monitoring, and internal equipment inspection.

　　What should be noted when using a microreactor?

　　A reaction vessel is a type of reaction equipment; pay attention during operation. Otherwise, it may be damaged for various reasons and forced to halt production. There are many aspects that require careful attention when operating a reactor.

　　First, operate the reaction unit strictly in accordance with the rules and regulations.

　　Second, before operation, carefully check for any discrepancies. During normal operation, keep the top cover and terminal blocks of the board open to prevent electric shock. It is strictly forbidden to manipulate the belt pressure. While conducting the pressure test using nitrogen, closely monitor the changes in the pressure gauge. Once the test pressure is reached, immediately shut off the nitrogen valve. The heating rate must not be too fast, and pressurization should also be carried out gradually. In particular, the stirring speed must be allowed to increase only at a slow rate. When the float is heated to high temperatures, avoid direct contact with it to prevent burns. After the experiment is completed, first allow the system to cool down. To prevent damage caused by excessive temperature differences and pressure fluctuations, do not subject the system to rapid cooling. At the same time, promptly disconnect the power supply.

　　After using the reactor simultaneously, be sure to perform regular maintenance so that only the high-pressure section can enjoy a longer service life.