Guidelines for safe operation and maintenance of solid feeding devices in reaction vessels

Solid feeding device for reaction kettleIt is a key equipment for achieving precise and safe feeding of solid materials into reaction vessels, mainly composed of feeding ports, conveying components (such as screw conveyors, vacuum feeders), sealing mechanisms, dust removal devices, and control systems. Its core function is to avoid problems such as dust leakage and deviation in feeding amount during the feeding process, ensuring the stability of the reaction process and the safety of operators. It is suitable for various reaction kettle systems in industries such as chemical, pharmaceutical, and food that require solid feeding. ​

1、 Preparation before operation

Material inspection: Confirm that the type, purity, and particle size of the solid material to be added meet the process requirements, and there are no lumps, impurities, or moisture phenomena; If the material is prone to moisture absorption and dust, it is necessary to prepare for moisture and dust prevention in advance (such as using sealed packaging bags or pre crushing agglomerated materials). ​

Equipment inspection

Appearance inspection: Check whether the sealing cover of the feeding port is intact, whether the conveying pipeline is damaged or blocked, and whether the filter bag of the dust removal device (such as bag filter) is clean and undamaged. ​

Function check: Start the control system and test whether the conveying components (screw/vacuum feeding) run smoothly and without abnormal noise; Check the sealing performance of sealing mechanisms (such as mechanical seals and packing seals) to ensure no leakage; Verify the accuracy of the weighing module (if any), and control the error within the allowable range of the process (usually ≤± 0.5%). ​

Safety preparation: Operators need to wear protective equipment (dust masks, protective gloves, anti-static work clothes); Clean up debris in the feeding area to ensure smooth emergency access; Check the ventilation and explosion-proof facilities (such as explosion-proof lamps and combustible gas detectors) on site for normal operation. ​

2、 Standard Operating Procedure

（1） Manual feeding (suitable for small batches, materials without special dust requirements)

Close the feed valve of the reaction kettle, open the dust removal system of the feeding device, and maintain a negative pressure state (negative pressure value ≥ -5kPa) to prevent dust diffusion. ​

Slowly open the sealing cover of the feeding port and pour the pre treated solid material evenly into the feeding hopper to avoid blockage caused by excessive feeding at once. ​

Activate auxiliary conveying components (such as vibration feeders), control the material feeding speed (usually ≤ 50kg/min according to the reactor volume), observe the flow state of the material in the conveying pipeline, and avoid stagnation. ​

After the feeding is completed, turn off the auxiliary conveying components and keep the dust removal system running for 5-10 minutes to remove residual dust in the pipeline; Subsequently, close the dust removal system, tightly seal the feeding port, and record the feeding amount, time, and equipment operation. ​

（2） Automatic feeding (suitable for large quantities and high-precision materials)

Enter parameters such as feeding amount (deviation between set value and process requirements ≤ ± 0.1%), conveying speed, etc. on the control system interface, start the equipment self-test program, and confirm that there are no faults in the weighing module, conveying motor, sealing valve, and other components. ​

After passing the self check, the system automatically opens the sealing valve, dust removal system, and conveying components, and the material enters the weighing module for measurement through the material bin; When the actual feeding amount reaches the set value, the system automatically closes the conveying components and sealing valves, completing precise feeding. ​

After feeding, the system automatically starts the pipeline blowing program (compressed air blowing or negative pressure suction) to remove residual materials; After the blowing is completed, generate a feeding record report (including feeding amount, time, and equipment operating parameters), and the operator needs to verify the report and sign for confirmation. ​

3、 Safety precautions

It is strictly prohibited to open the sealing cover of the feeding port or touch the moving parts of the conveying components (such as spiral blades) during equipment operation to prevent mechanical injury; If maintenance is required, the power and gas sources of the equipment must be cut off first, and a "No Operation" warning sign must be hung. ​

For flammable and explosive materials, the feeding device needs to be grounded (grounding resistance ≤ 4 Ω) to avoid static electricity accumulation; At the same time, it is prohibited to use open flames in the feeding area, and the sealing of explosion-proof components (such as explosion-proof motors and junction boxes) should be checked regularly. ​

If there is a pipeline blockage during the feeding process, the equipment should be stopped first, and the blocked material should be cleaned through "reverse blowing" or "manual dredging holes". It is strictly prohibited to forcefully start the equipment to prevent motor overload damage. ​

Operators must undergo professional training and be qualified before they can take up their posts. They should be familiar with the location of the emergency stop button of the equipment (usually set next to the feeding port and the control system interface). In case of abnormal situations such as dust leakage or abnormal equipment noise, they should immediately press the emergency stop button, troubleshoot the problem, and then restart. ​

4、 Maintenance requirements

Daily maintenance: Check the sealing gasket of the feeding port for aging or damage before feeding, and replace it promptly if there are any problems; Clean the dust on the surface of the filter bag of the dust removal device to ensure the breathability of the filter bag (resistance ≤ 1500Pa); Check the lubricating oil level (such as the bearings of the conveying motor), and if it is insufficient, replenish the corresponding type of lubricating oil (refer to the equipment manual). ​

Regular maintenance: Calibrate the weighing module weekly and verify the measurement accuracy using standard weights (accuracy ≥ 0.01kg). If the deviation exceeds the allowable range, professional personnel should be contacted for adjustment; Check the sealing condition of the pipeline connections every month, tighten loose bolts to prevent material leakage; Disassemble and inspect the sealing mechanism (such as mechanical seals) every quarter, and replace worn seals (such as dynamic and static rings). ​

Long term maintenance: Conduct comprehensive disassembly and maintenance of equipment every year, replace aging conveying components (such as spiral blades and conveyor belts), and electrical components (such as sensors and contactors); Perform software updates and parameter calibration on the control system to ensure long-term stable operation of the equipment; Establish equipment maintenance records, recording the maintenance time, content, and replacement part models for easy traceability.