Precautions for loading hydrogenation catalysts

Catalyst loading: 1 Prepare the tools for catalyst loading, scales, lifting equipment, lifting hoppers, filling hoppers, canvas bags, rope ladders, protective clothing, tape measures, record sheets, etc. 2 Choose a sunny day to load the catalyst; transport it to the site in advance and cover it with canvas. 3 The filled porcelain balls are transported to the site, and after inspection it is determined whether they need to be cleaned. If cleaning is necessary, they are rinsed with water, dried, and then arranged in categories. 4 Assign dedicated personnel for weighing, recording, lifting, leveling, and calculation. 5 The technicians mark the catalyst filling dimensions in the reactor according to the filling plan provided by the design institute or catalyst manufacturer. 6 Blind plates are installed at the inlet and outlet of the reactor to isolate it from the system. 7 Once all the internal components of the reactor have been installed, they must be inspected and verified by technical personnel. 8 The catalyst factory develops a loading plan and sends personnel to provide on-site support for the loading process. 2 Load the catalyst: 1 Organize the team to divide tasks (weighing, sieving, recording, loading). 2 Ground staff lift the ceramic balls to the reactor platform, pour them into the loading hopper, and load the various ceramic balls according to the specified dimensions. 3 Lift the catalyst to the reactor platform and install it. 4 Load the catalyst according to its loading height. 5 After the catalyst is installed, install the protective agent. 6 When loading the agent, install the internal components in order. 7 After the catalyst is loaded, immediately seal the reactor’s main cover, remove the blind flange, and wait for catalytic sulfidation. 8 Clean up the scene. 3 Precautions: Do not roll the catalyst on the ground to prevent it from breaking apart. When opening the containers of catalyst, keep 10 ml of sample in each container for catalyst analysis after mixing. After opening the barrel, decide whether to sieve it based on the condition of the catalyst. The catalyst must be loaded to the designed height. The catalyst is poured into the loading hopper and then introduced into the reactor; it must be done using canvas bags. When handling the catalyst, it is necessary to handle it gently, and the iron drums must not be rolled. Personnel involved in loading must strictly prevent other items from being brought into the reactor, such as keys, knives, wire, and lead wire. Persons entering the reactor must obtain a permit and wear dust masks. Before entering the reactor, a gas sample is taken from inside the reactor for analysis; only if it meets the requirements is entry permitted. The reactor must be isolated from the system by installing a blind flange. This post was last edited by grjq on 2008-3-2 11:22.]

1. Prevent the catalyst from coming into contact with water or humid air. 2. Avoid exposure to large amounts of toxic substances. 3. Prevent the catalyst from breaking. 4. If it is a pre-sulfurized catalyst, avoid exposing it to air. 5. Prepare a plan for loading the catalyst in advance. 6. Ensure that the internal components of the reactor are properly installed and have been inspected to confirm their suitability. 7. Check the dimensions of the ceramic balls and the catalyst before loading them. 8. Determine the appropriate amount of each type of catalyst and ceramic ball to be used, record the total amount of catalyst added, and compare this figure with the total amount of catalyst and ceramic balls remaining on site. 9. Fill the discharge pipes between the bed layers with ceramic balls

Chapter 16 Catalyst Loading Section 1 Preparation Work I. Conditions to be met before catalyst loading 1. The reaction system must be completely dry, and the reactor temperature must have dropped to normal levels (the temperature at any point in the reactor must be below 60°C). System compressed air displacement is complete; the oxygen content in the system is >20% (v). 2. The pressure in the reaction system has dropped to atmospheric level; there is no explosive gas in the system (the explosion gas analysis results are satisfactory), and the top cover of the reactor is ready to be opened. 3. Reactor safety isolation: (1) In accordance with the isolation plan, blind flanges are installed on all interfaces of the reactor or they are all opened, so as to completely isolate the reactor from the rest of the plant (blind flanges are shown in Table 1; isolation is illustrated in Figure 2). The large cover short section at the reactor inlet was removed to gain access; the feed line was blocked. The outlet stub was removed, and the outlet pipeline was sealed off; the lines for quench hydrogen, purge hydrogen, and pressure drop measurement were all sealed to prevent nitrogen or hydrogen from leaking into the reactor through the cold hydrogen interface or pressure drop interface. For areas that cannot be isolated using blind flanges but rather valves, after closing the valve, secure it with wire; if there is a vent valve, open it and attach a warning sign to that valve stating “Do not operate this valve during filling.” 5. Clearly mark the fresh water, nitrogen, instrument air, and industrial air lines at the top of the reactor to prevent their accidental mixing. Blind plates are installed for isolation at the points where the instrument air and nitrogen streams intersect in the device. 6. The electric winch, vacuum pump, and air compressor for air supply have all operated normally during testing. 7. Install temporary lighting on-site; provide 24V lighting inside the reactor to ensure operations at night. 8. The catalyst loading plan should be placed on site, along with appropriate signage. (The catalyst loading plan is shown in Table 6.) II. Preparatory work for catalyst loading 1. The catalyst loading plan and the implementation plan must be approved in advance. Coordinate all departments to ensure proper cooperation and provide training for the personnel responsible for loading. Board management is implemented at the loading site. 2. The specialized equipment for loading the agent, as well as the personal protective equipment for the operators, are ready, as shown in Table 5. 3. A dedicated person shall be fully responsible for loading the reactor and oversee the operations on site. 4. Safety supervisors shall be stationed at the charging site to inspect and verify the oxygen supply, gas supply, as well as communication and lighting facilities for personnel entering the reactor for work. They shall also check the validity of the work permits for entering the reactor, thereby fulfilling their responsibilities for ensuring safety during such operations. Be on duty at the site during the gas protection ambulance loading process. 5. Before entering the reactor, contact the laboratory to conduct the necessary testing and analysis. The laboratory analysis items are listed in Table 2. 6. Check that the hopper and feed base are clean and free of debris; ensure that the sliding plates move smoothly, and that the canvas feed tube is properly connected. 7. The catalysts should be delivered to the site in advance and arranged neatly as required. The requirements for transporting and placing the catalyst are as follows: (1) Deliver the catalyst to the site on time in accordance with the loading schedule, unload it using a forklift, arrange it by type, and cover it with tarpaulins. Falling and collisions are strictly prohibited. (2) Catalysts should be arranged reasonably according to the same model, the same production batch number, and the order of installation, and distinguished with identification tags; they must not be placed randomly. (3) When storing catalysts on-site, measures should be taken to protect them from rain and moisture. Cylindrical catalysts should be placed neatly on a higher concrete surface near the reactor, and covered with rainproof sheets. For bagged catalysts, wooden pallets must be placed on a raised concrete surface near the reactor, waterproof sheets laid down, the catalysts then stacked on top of these pallets, and covered with rainproof sheets to prevent soaking due to rain or leaks from the equipment. (4) When stacking catalysts on-site, it is essential to properly plan the working space for cranes, forklifts, and personnel during loading to avoid chaos in the loading process. (5) Once the catalyst sealing tank is opened, it should not be left exposed to the air for an extended period of time; the tank lid should be opened according to the demand from the next hopper. After opening the plastic bag inside the barrel, the catalyst should be immediately poured into the hopper for loading. The catalyst that was not loaded on that day should be repackaged and stored in a barrel. (6) Stop loading operations in rainy weather. A temporary rainproof tarpaulin should be installed on top of the reactor platform, while the reactor inlet and the material holder should be covered with iron lids and tarpaulins. (7) Open the reactor head cover and protect the sealing surfaces of all high-pressure flanges in the reactor; any damage to them is strictly prohibited. The reactor inlet sealing surface is protected with rubber gaskets. 8. The interior of the reactor is purged with industrial air; the reactor’s vacuum pumping system is activated to remove the gases inside. Work can only begin once it is confirmed that the oxygen level in the reactor is below 20%, and that there are no flammable or toxic gases present. The operators can also wear compressed air respirators to remove the internals at the reactor inlet at the reactor mouth. 9. Remove the reactor channel plate. The steel ladder used to descend into the bundled reactor must have each section securely fixed and verified. Install lighting inside the reactor; the required voltage for the lighting is 24 volts. Install the vacuum tube and air supply tube. 10. Mark the catalyst filling height: After entering the reactor, technicians measure and mark the filling heights of the ceramic balls and various catalysts using a fluorescent pen or colored chalk. 11. Other loading equipment and facilities are in place. (1) The catalyst loading hopper at the top of the reactor has been installed; a 600×1000 mm wooden board is placed inside the hopper to prevent the catalyst from being damaged. Sufficient space is left between the bottom of the hopper and the reactor inlet to allow personnel or equipment to easily enter the reactor. Install the filler in the canvas tube and insert the baffle. Also, prepare a spare canvas tube for replacement in case of wear or breakage. (2) Organize the vacuum hose and air hose; the end of the vacuum hose should be equipped with a screen to prevent catalyst particles from being drawn into the vacuum system. The air hose inside the device should have its end facing upward (not downward into the catalyst bed); it is recommended to use compressed and dried air from the atmosphere as the air source. Under no circumstances should a nitrogen-containing air source be used as a backup air supply in case of a failure. (3) Connect the anti-static grounding wire when loading the agent, in order to discharge any static electricity generated. (4) The two feed hoppers on the ground are in place. III. Final inspection of the reactor and its internal components prior to loading 1. The following steps are to be carried out by experienced professional technicians. Note: Only after the reactor meets the entry requirements and a confined space work permit is issued can work be carried out inside the reactor. 2. Use a magnet to verify that the internal components and inner walls of the reactor are all made of austenitic stainless steel (non-magnetic). 3. Check that the thermocouple sleeves on the reactor are properly installed, securely supported, and undamaged; coloring inspections can be carried out on key areas. 4. Check that the inlet distributor is installed correctly. 5. Carefully inspect each bed layer in the reactor, and check that the reactor walls and internal components are clean; visually ensure that there is no dust, rust, or debris on the reactor’s perforated plates and gas lift plates. The support mesh is intact; the gaps between the porous disk and the vessel walls are filled with asbestos rope, with these gaps being less than 1.2 mm to prevent the catalyst from entering the distribution disk. Use a flashlight to shine on the side of the support mesh and visually check that all mesh openings are unobstructed; if not, clean them thoroughly with an iron brush. Use a flashlight to check that the small orifice in the cold hydrogen tube nozzle is not blocked; otherwise, use a thin wire to clear it. 6. Check the reactor cold hydrogen loop; the internal flanges are tightly sealed. 7. Check the discharge port of the reactor to ensure that the cover is properly installed on the port, and that there is no water or other debris in the discharge port; then secure the blind flange to the discharge port using bolts. 8. Check and confirm that the bubble caps of each layer’s distributor are tightened properly. 9. After assembly, check all key bracket connectors and take photos for reference. 10. The reactor must be kept clean and dry, free of water accumulation, dirt, waste, or any unrelated substances. A final inspection should be carried out before the catalyst is loaded; a vacuum cleaner or cotton balls can be used to remove any small debris. In addition, all tools brought into the reactor must be checked after they are removed from it, as it is strictly prohibited to leave tools inside the reactor. Section 2: Catalyst Loading I. Steps for Catalyst Loading 1. Procedures on the ground (1) In accordance with the catalyst loading plan, and under unified command and coordination, place the catalyst in barrels on the concrete surface near the reactor. Use manual labor and a forklift to transfer these barrels onto a scale for weighing, with a dedicated person responsible for keeping track of the weights. Then, manually load the catalyst into the feed hopper on the ground (a 600×1000 mm wooden board should be placed inside the hopper to prevent the catalyst from being damaged). Use a crane or electric hoist to lift the feed hopper to the loading hopper at the top of the reactor. Throughout the loading process, the quality of the catalyst should be checked regularly, and samples should be taken and retained. (1) Slowly open the plug at the bottom of the feed hopper to unload the catalyst into the packing hopper at the top of the reactor. After the catalyst has been unloaded, it is transported to the ground using a crane or electric hoist, after which the next process is repeated. Note: The falling distance of the catalyst between the two hoppers should be as short as possible to prevent fragmentation. 2. Operating procedures for the top and interior of the reactor: (1) An air extractor is installed at the reactor inlet to continuously remove the catalyst dust generated within the reactor, thereby creating convection and ensuring a favorable environment for loading the catalyst. The hose should be suspended in the reactor at a height of 0.5–1 m above the workers’ heads (approximately 2 m above the catalyst surface), to prevent the vacuum hose from being pulled down onto safety helmets, clothing, etc. (2) Lower the ladder and lighting equipment to maintain an appropriate level of brightness inside the reactor for the operators to work in. As loading proceeds, keep the ladder at an appropriate distance above the reactor’s material surface to facilitate the replacement of workers and routine inspections. (3) Following the filling dimension lines marked in advance by the technical staff, the filler shall tighten and connect each section of the metal filling tube located behind the slide valve under the filling hopper (if canvas hoses are used, they must be tied securely, and the hoses must be long enough) ； As the catalyst level rises, the excess portion can be cut off with scissors); finally, a canvas tube about 1.5 meters long is installed below the pipe. Depending on the rise in the catalyst level, the metal tubes can be removed section by section to maintain an appropriate filling height of the catalyst. The canvas tube must be filled completely with catalyst to prevent it from breaking due to falling from a height. (3) Prepare two sets of specialized fresh air breathing equipment at the top of the reactor, as well as a set of common tools, life-saving ropes and other life-saving supplies. Inside the reactor, on the upper trays of the bed layer, prepare two sets of specialized fresh air breathing equipment and one set of emergency lights. If night work is required, be prepared with lighting tools such as flashlights. (4) Two charging personnel wear fresh air breathing equipment, communication devices (walkie-talkies), gloves, protective shoes, special coveralls, and safety ropes tied around their waists. The two of them descend into the reactor simultaneously to check the height of the slide valves installed on the canvas pipes inside the reactor, as well as the height of those canvas pipes relative to the loading surface, and to check the tightness of the pipes. They also examine the clarity and accuracy of the markings inside the reactor. When the operator in the reactor wants to stop catalyst loading, the canvas pipe opening can be secured using a convenient steel clip or soft rope. (5) Before starting to load the catalyst into each bed layer, the catalyst discharge pipe must be carefully filled with ceramic balls. For details on the packing of ceramic balls and catalysts, refer to the catalyst packing diagrams for each reactor (Figure 1). (6) After loading the catalyst into each bed, it is necessary to check and confirm that the catalyst discharge pipe of the upper bed is inserted 500 mm below the catalyst level in the lower bed, to ensure that the discharge pipe does not become empty due to the drop in the catalyst level after operation begins. (7) When loading the catalyst into the reactor, the person responsible for this task first firmly holds the lower end of the canvas hose to ensure that the hose is filled with catalyst. The loader should avoid standing directly on the surface of the catalyst and should stand on a 500×500 mm wooden board to reduce catalyst fragmentation. The catalyst flowing out of the canvas hose must be distributed evenly across the entire cross-section of the reactor; it cannot be simply poured in the middle of the material surface. While one person is loading the catalyst, another uses a wooden rake to level the surface of the catalyst, ensuring it is spread evenly so that no area has a buildup of more than 100 mm. In addition, special attention should be paid to the distribution of catalyst around the thermocouple sheaths and the reactor walls, to ensure even and proper packing and prevent channeling from occurring in those areas after operation begins. The filler should walk on the wooden boards placed on the surface of the catalyst (boards measuring 50×100–120 cm), in order to minimize the risk of the catalyst being crushed due to pressure. After filling several hoppers with catalyst, the surface of the catalyst must be carefully leveled and its height measured; technicians then calculate the filling density and compare it promptly with the filling diagram. When the level of the catalyst is less than 400 mm from the bottom of the canvas hose, cut the hose short and continue with the catalyst loading; be sure to remove all canvas debris from inside the reactor at this time. The vacuum tube should rise as the operator and the material level increase. When the catalyst level reaches about 900 mm above the riser tray, a wooden rake must be used to push the catalyst to the sides, creating a concave surface so that the catalyst bed can be filled as completely as possible. The typical loading rate is about 2–2.5 m3 per 20–25 minutes; too fast a loading rate results in too low a catalyst packing density as well as the generation of large amounts of static electricity. (8) During the reactor charging process, any excess ladders, vacuum tubes, ventilation pipes, lighting wires, and anti-static copper wires must be removed from the reactor at all times. Note: Lighting wires and anti-static copper wires should be kept from getting wrapped around the ladder. (9) After installing the second or third bed layer, clean all the tools used for each bed layer and put them together in one place. Use a vacuum tube, air duct, or cotton ball to carefully remove the catalyst and dust from each layer of the disk. (10) Contact the relevant personnel to install the reactor internals; each bolt must be cleaned thoroughly and evenly coated with a high-temperature anti-seize agent, while the nuts should also be cleaned, and threading may be performed if necessary. After installing the inner components in each layer, technicians must conduct inspections to verify whether the components are deformed, whether the bolt holes are of appropriate size, whether the levelness meets the requirements, and whether there is any damage to the catalyst support plates, in order to prevent the catalyst from falling into the inner components. (11) When installing at the top of a bed layer, it is necessary to use scale baskets; these baskets should be placed evenly and uniformly, with ceramic balls (or catalysts) used to fill them. Catalysts (or ceramic balls) must not be placed inside the scale baskets. Finally, each scale basket should be connected together using steel wire. (12) Seal the reactor cover, remove all isolation blind plates, and seal the catalyst discharge port.  Before sealing the reactor lid, ensure that no equipment (rakes, wooden boards, ladders, tarpaulins, tools) is left inside the reactor.  Remove the material holder, and tidy up all other items, putting them back in their proper places.  Install the internal component channels, and inspect and confirm them.  Before sealing the reactor cover, the metal gaskets and the sealing surfaces of the flange grooves must be carefully inspected and cleaned to ensure they are in good condition and free of dirt. When sealing the cover, technicians provide on-site guidance to tighten the flange strictly in accordance with the sealing requirements, and use calipers for inspection to prevent misalignment. II. Safety measures, requirements, and precautions for catalyst loading 1. Ensure that the reactor is isolated as required to meet safety conditions. 2. The personnel responsible for loading the material must wear full-body suits, as well as fresh air breathing equipment, protective goggles, gloves, and safety shoes. Try to avoid direct contact with the catalyst, and those loading it should wear safety ropes. 3. Strictly conduct “three-gas” analysis in the reactor in accordance with regulations, and personnel entering the reactor must hold a confined space work permit. As long as there are people working inside the reactor, it is necessary to ensure the proper operation of the air evacuator. 4. The personnel working inside the reactor and the supervisors stationed on top of the reactor must maintain constant communication through sound, visual signals, and walkie-talkies at all times. Two operators work in the lower reactor at a time, and each operation lasts no more than 30 minutes. 5. Personnel operating electric cable cars must receive specialized training. During the transport of catalyst in the hopper, it is strictly prohibited to have anyone standing at the bottom or in the surrounding area. 6. The site must be equipped with medical personnel as well as life-saving equipment such as stretchers and ventilators. 7. The relevant responsible persons and technical staff shall record the catalyst loading report for the day (Form 3) and the catalyst loading record sheet (Form 4)