Catalyst loading is a core pre-commissioning procedure for chemical reaction units. The loading quality directly impacts reactor bed pressure drop, fluid distribution and catalytic efficiency, and even determines the long-term stable operation of the whole unit. To avoid loading defects and eliminate potential safety hazards, standardized pre-loading inspections must be fully implemented before formal loading of fresh catalysts.
First, conduct quality inspection on the catalysts themselves. Verify that the model, specification and batch number of catalysts match the design documents to prevent wrong or mixed loading. Check the integrity of catalyst packages for damage, moisture, caking and pulverization. Any deteriorated or unevenly sized catalysts due to moisture shall be rejected. Randomly sample catalysts to inspect their appearance; intact pellets without excessive fine dust are required. Sieving is adopted when necessary to remove impurities so as to avoid bed blockage and excessive pressure drop during operation. In addition, check certificates of analysis and test reports to confirm key indicators including mechanical strength, activity and particle size distribution comply with process design requirements.
Second, carry out internal inspection of the reactor. Thoroughly clean the reactor interior to remove residual welding slag, rust, debris and oil stains from construction, ensuring a completely clean internal space. Inspect the reactor inner wall, support gratings, sieve plates and packing screens. Confirm gratings are free of deformation, damage and excessive gaps, and screens are tightly attached without holes or breakages to prevent catalyst leakage and fluid maldistribution. Meanwhile, check internal dimensions and marked reference lines of bed height for accurate control of loading depth. Close all equipment manholes after inspection to avoid secondary foreign matter falling into the reactor.
Finally, inspect pre-loading supporting conditions and tools. Check loading tools such as funnels, hoses, buckets and screening equipment to guarantee they are clean, dry, intact and free of contaminants. Confirm on-site ventilation, dust-proof and anti-static facilities are functional, fire fighting equipment is complete and effective, and the working area is tidied up. Verify the process status of the unit: the reactor has been depressurized, cooled down and fully purged with qualified gas detection results, complying with confined space operation and loading safety regulations. Catalyst loading can only be initiated after all inspection items pass and relevant records are fully filed.