1High temperature and high pressure reactorPreparation before startup: Ensure the safety of equipment and personnel
Equipment inspection and cleaning
Sealing inspection: Check whether the kettle body, kettle cover, and sealing ring are intact, without cracks or wear. When installing the cover, tighten the main bolts diagonally multiple times to avoid tilting and sealing failure.
Valve and pipeline inspection: Ensure that the inlet valve, exhaust valve, pressure gauge, and explosion-proof membrane pipe openings are unobstructed and free from material blockages. If blockage is found, it needs to be disassembled, cleaned, and reinstalled.
Cleaning and drying: Clean the inner wall, stirring blade, cooling coil, and joint surface of the kettle with ethanol, then rinse and dry with distilled water to prevent cross contamination.
Security Attachment Verification
Check if the safety valve, pressure gauge, and temperature sensor are within their valid calibration period to ensure their sensitivity and reliability.
Test whether the alarm system (such as over temperature and over pressure alarms) is normal and whether the interlocking device is effective.
Environmental and personnel requirements
Two or more people are required to collaborate in the experiment, and it is strictly prohibited to work alone.
Ensure good ventilation, turn on the ventilation fan, and avoid the accumulation of flammable gases.
2、 Startup operation: Standardize processes to reduce risks
Sealing and pressure testing
Sealing operation: Place the kettle body into the heating furnace, slowly close the lid to avoid collision of the sealing surface. After adding the gasket, use a torque wrench to tighten the bolts in a cross symmetric manner multiple times (new kettle 70-100N · m, old kettle 100-150N · m).
Pressure test: Slowly increase the pressure with inert gas (such as nitrogen) to the test pressure (100-105% working pressure), hold for 5 minutes every 20% working pressure, hold for 30 minutes after reaching the test pressure, and check for leaks. If the pressure drops by more than 0.05 MPa, it is necessary to check for leaks (such as interfaces, needle valves, thermometer probe sockets), tighten them, and retest the pressure.
Feeding and gas replacement
Feeding restrictions: The solvent must not exceed the allowable feeding coefficient of the inner tank, and the use of low boiling point volatile reagents (such as acetone and benzene) is strictly prohibited.
Gas replacement: Inject nitrogen gas repeatedly 3-5 times to remove air from the kettle. If hydrogen gas needs to be introduced, the nitrogen gas should be emptied first, and then slowly filled with hydrogen gas to the reaction pressure to avoid static electricity causing explosions.
Heating and mixing control
Heating rate: not exceeding 80 ℃/hour, adjust the set temperature step by step to prevent local overheating.
Stirring start: First turn on the cooling water, then start stirring, with a speed of>100rpm/min to ensure uniform dispersion of the material.
3、 Operation monitoring: real-time response to abnormal situations
parameter monitoring
Pay close attention to changes in temperature, pressure, and rotational speed, especially be alert to sudden pressure increases. If the pressure is too high, immediately cool down or vent from the exhaust valve (hydrogen needs to be discharged outdoors).
Record key parameters such as current and voltage for later analysis.
Sampling standards
Sampling during the reaction should ensure that the system is homogeneous. After stopping stirring, let it stand for 10 minutes before sampling. Take a sample approximately 20 milliliters after the first discharge to avoid any residual material in the pipeline affecting the results.
emergency response
Leakage: Immediately turn off the power and heating equipment, evacuate personnel, ventilate and reduce pressure.
Overpressure: Relieve pressure through exhaust valve or safety valve to ensure unobstructed pressure release channel.
Fire: Use dry powder fire extinguishers and strictly prohibit using water to extinguish flammable liquid fires.
4、 Shutdown operation: Safety termination reaction
Cooling and pressure reduction
Turn off the heating system, let it cool naturally or let it cool down to room temperature with cooling water.
Slowly release the pressure inside the kettle, and it is strictly prohibited to quickly reduce the pressure, which may cause equipment damage or reagent splashing.
Open the kettle and clean it
After ensuring normal temperature and pressure inside the kettle, loosen the bolts symmetrically and lift the kettle cover evenly to avoid damage to the sealing surface.
Clean the kettle and electrodes with ethanol to remove residue and prevent corrosion.
Equipment maintenance
During long-term shutdown, drain the refrigerant and water source, and keep away from corrosive substances.
Regularly inspect the sealing ring, mixing blade, and bearing components, and replace worn parts.
5High temperature and high pressure reactorRisk prevention and control: eliminate accidents from the source
Material Management
It is strictly prohibited to use substances with low self ignition point and flash point (such as low flash point Class A flammable liquids) to avoid leakage and the formation of explosive mixtures.
Control the amount of catalyst, add it evenly, and prevent the reaction from getting out of control.
Equipment maintenance
Regular maintenance to prevent mechanical impurities from falling into the kettle and improve maintenance quality.
Check the electrical system to ensure good grounding and prevent static electricity accumulation.
personnel training
Strengthen operational skills training and familiarize oneself with emergency response procedures (such as leak and fire handling).
Strictly follow the operating procedures and eliminate illegal operations (such as opening a kettle under high temperature and pressure).