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Pre-conversion Catalyst Manual This manual contains the instructions for loading, starting up, and shutting down the pre-conversion catalyst. Reforming catalysts are used to carry out steam reforming of hydrocarbon feedstocks in adiabatic reactors, converting the higher hydrocarbons in the feedstock into a mixture of H2, CO, CO2, and CH4. The catalyst is placed in a steel tank with a nominal capacity of 200 liters. Inside the barrel, a polyethylene inner bag protects the catalyst from moisture. The steel tank is equipped with a removable lid. If the following guidelines are followed, the catalyst in the steel tank can be stored indoors for many years. Steel drums should be transported as gently as possible, and it is best to transport them in an upright position without rolling. Before storage, it is necessary to check all steel cylinders for any damage caused during transportation. If any sand holes or cracks are found, it is necessary to find a way to seal them, such as by filling them with material. This is very important for preventing the catalyst from coming into contact with air and respiring, as well as for preventing the catalyst from getting wet. It is highly recommended to store the barrels in a well-ventilated warehouse. The barrels should be stored in dry and corrosion-resistant conditions. If the storage environment is very humid, the drum should be checked regularly. Protect by repainting when necessary. Outdoor storage: If storage must take place outdoors, the storage period will inevitably be shortened. It is necessary to protect the drum thoroughly from rain and moisture in the ground during storage. Stacked steel drums should be placed on logs or pallets. And cover it with plastic or canvas to keep it waterproof and dustproof. They should be placed on concrete sleds or similar objects to protect them from potential floods. Safety instructions for handling and loading: Dust from catalysts contains compounds that can irritate the skin, eyes, and respiratory system. Therefore, the processing should aim to minimize dust formation. Protection of personnel: Masks, gloves, and full-body protective clothing are used to protect those who handle the catalyst from exposure to catalyst dust. Rain protection: It is necessary to prevent the catalyst and the interior of the reactor from getting wet due to rain. The screening area and the top access hole of the reactor need to be covered with protective cloth. Screening: It is usually not necessary to screen the catalyst. If the drum is handled roughly during transportation, it may be necessary to screen the catalyst at the bottom of the drum. Screen size: Choose a screen with openings of 1 mm. The filtering operation must be carried out carefully. The sieve should be easy to tilt, at an angle sufficient to allow the catalyst to move easily. To minimize catalyst wear, avoid vigorous shaking of the sieve; the catalyst can be manually screened using a rake. Air soot blowing: Use clean and dry compressed air to blow away dust and fine particles. Catalyst stability: Upon delivery, the catalyst was pre-reduced, but it remains stable only in air at temperatures below 70°C (160°F). If, for some reason, the catalyst in the tank is heated above this temperature (for example, by high-temperature radiation), it may begin to oxidize in the presence of air. The oxidation process is accompanied by the generation of heat. If this occurs, the appropriate course of action is to tighten the lid or replace it in order to reseal it and prevent further air from entering, then reopen it after the bucket has cooled down. During loading, the bottom of the reactor must be completely sealed to avoid a chimney effect inside the reactor. As an additional safety measure, nitrogen connection nozzles are provided to purge from the bottom of the reactor. After checking the bottom support of the reactor, a layer of 100 mm (4” / 1/2”) alumina balls along with a catalyst grid, or a 1” alumina ball bed with a wire mesh is placed at the bottom of the reactor. Due to the volatility of silica under steam conversion conditions, all bottom support balls must be of the alumina type. Then, the catalyst is loaded into the reactor using a catalyst loading tool. To prevent breakage during loading, a slide arranged with hoses is used so that the catalyst descends by no more than 1 meter (3 feet). Do not pour all the catalyst into one pile; instead, mix it evenly by tilting it from time to time. The most convenient way to load it is to have personnel enter the reactor, pass the catalyst barrel to them, or have them guide the loading hose. In this way, the catalyst surface can always be maintained at a reasonable level. People in the reactor should not step directly on the catalyst; instead, they should use \"snow shoes\" or stand on wooden planks to distribute their weight. And carefully remove any foreign objects. Fresh air supply: Any personnel working inside the reactor must be equipped with breathing apparatus, and the reactor should have a life support system connected to the air outside the reactor. Top protection: It is recommended to place a layer of alumina balls with a diameter of 100–200 millimeters (4–8 inches) and a thickness of 1 unit on top of the catalyst, so as to protect the catalyst from being disturbed by turbulent gas flow and to aid in the distribution of the feed gas. If necessary, a floating screen or wire mesh can be placed between the balls and the catalyst, so as to easily separate the alumina balls from the catalyst during the next catalyst replacement and unloading process. Due to the volatility of silica under the steam conversion process conditions, all the top ceramic balls must also be of alumina type. Nitrogen protection: After loading is complete, the reactor should be isolated from the outside environment and maintained under a slight positive pressure of nitrogen to prevent process gases, steam, and condensates from entering, as well as moist air from entering from the atmosphere. Commissioning: The catalyst has been pre-reduced, so no reduction is required during commissioning. However, it must be started and stopped in accordance with the design procedure to prevent the catalyst from being oxidized. Under normal circumstances, reducing an oxidized catalyst requires high temperatures and recirculation equipment; such equipment is either not built into the production unit or additional air circulation devices are needed. Furthermore, oxidation and re-reduction processes will shorten the catalyst's active life. Therefore, catalyst oxidation should be avoided during operation. The above procedures serve as standard guidelines and can be adjusted according to the actual conditions of the factory.