Precautions for Using Laboratory Reactors

　In the daily use and management of laboratory reactors, failure to follow operating procedures can lead to serious accidents such as personnel injuries and equipment malfunctions. These incidents may include reactor explosions, explosions of reaction products, and releases of toxic substances. So, let’s now take a closer look at the precautions for using laboratory reactors!

　　Precautions for Using Laboratory Reactors

　　1. Sealing performance

　　The laboratory reactor is a precision piece of equipment; therefore, to avoid damage caused by various types of impacts, special attention is paid to the sealing conical surfaces. When installing the lid, first place the reactor vessel body, then push the reactor lid into position. The sealing is achieved through contact between the conical surfaces and the sealing ring, and the lid should be carefully fitted onto the vessel body. When tightening the main bolts, ensure even distribution of force and prevent the lid from tilting to one side. To achieve a good seal, do not exceed the specified tightening torque, and tighten the bolts gradually in multiple stages, symmetrically and diagonally. The sealing effect is attained by pressing the components tightly against each other as the main bolts are tightened. If the sealing surface is damaged, it must be repaired promptly to restore proper sealing performance and prevent further damage or accelerated wear of the sealing surface. All threaded connections must be lubricated with oil or a mixture of oil and graphite during assembly. If necessary, the components should be re-machined for repair.

　　2. Sealed operation

　　The inlet and outlet valves of the laboratory reactor are sealed with needle valves. To close them, simply turn the valve needle gently to press down on the sealing surface, ensuring a tight seal. Please avoid applying excessive force, as this could damage the sealing surface.

　　3. Heating and Pressurization Test

　　Before using the laboratory reactor vessel, a heating and pressurization leak-test must be conducted. The use of oxygen and other flammable or explosive gases is strictly prohibited. Heating and pressurization should be carried out gradually. The heating rate should be no more than 80 degrees per hour. During the trial run, air or nitrogen can be used as the test medium; however, an inert gas must be employed. The pressure should be increased in increments of 20% of the working pressure, with each increment held for 5 minutes before proceeding to the next step. Once the test pressure is reached, hold it for 30 minutes to thoroughly check for leaks. The test pressure should be set at 100–105% of the working pressure. If a leak is detected, reduce the pressure, carefully tighten the nuts and fittings, and then connect the reactor’s inlet valve to the compressor (or high-pressure pump) using a connecting pipe. Pressurization should be performed in two separate stages; under no circumstances should nuts and fittings be tightened while the vessel is under high pressure.

　　4. Cooling process

　　During reactions in laboratory reactors, rapid cooling and rapid heating are prohibited to prevent cracks from forming in the reactor vessel due to excessive thermal stress. After the reaction is complete, loosen the bolts symmetrically and evenly before removing them. When opening the lid, pay special attention to protecting the sealing surface; lift the lid uniformly. First, allow the reactor to cool down—either by circulating water for cooling (in exothermic reactions) or by air cooling—and then release any high-pressure gas inside the reactor until the pressure drops to atmospheric level. This precaution prevents damage to the sealing gasket caused by collision between the lid and the reactor body.

　　5. Subsequent processing

　　After each operation, remove any residual materials from the reactor body and reactor lid. All sealing surfaces of the autoclave should be carefully cleaned and dried. Do not use hard objects or soft materials with rough surfaces for cleaning.

　　Maintenance of Laboratory Reactors

　　Regular inspections ensure that safety devices such as safety valves, rupture discs, pressure gauges, and thermometers are accurate, sensitive, and easy to use. Properly mark the red line on the pressure gauge to prevent any internal leakage from the rupture disc; ensure that there is no abnormal vibration or noise inside the reactor vessel.

　　Check the operating temperatures of various components, including the gearbox, motor, and bed bearings. The typical temperature is 40°C, with a maximum allowable temperature of 60°C. (It’s normal if you can hold your hand on the surface for more than 8 seconds.)

　　Ensure that all inlet and outlet valves of the reactor are fully functional, and any issues should be addressed promptly.

　　The flange and base of the reaction vessel must not have any loose bolts. The safety guard must be intact and reliable.

　　The reactor body itself should not exhibit cracks, deformation, bulging, perforations, corrosion, or leaks.

　　Maintain good equipment hygiene, free of oil stains, and ensure the equipment’s original color is clearly visible.

　　Regularly inspect the condition of internal components such as agitators and coil tubes, tighten any loose bolts, and replace relevant parts as necessary.

　　The above is a summary of the precautions for using laboratory reactors. If you’d like to learn more, feel free to contact us anytime!