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Construction plan for the reactor head removal in the jet fuel hydrogenation reactor. Brief explanation of the reason for shutdown: Currently, the differential pressure in the reactor of the kerosene hydrogenation unit has reached 0.20 MPa (values under full-load operation). Single bed layer; the design can achieve 0.45 MPa), with a rapid upward trend. Following discussions, the company has decided to shut down the kerosene hydrogenation unit in the near future (from January 5 to 9, 2010) for a cleaning operation, in order to address the issue of high differential pressure in the reactor. The main tasks involved in this shutdown and top cleaning operation are as follows: 1. This top cleaning is carried out in a nitrogen-rich environment under anaerobic conditions; under these conditions, the protective agent located at the top of the reactor (1.3 tons, approximately 78 cm ； There is also 0.7 tons of ceramic balls, about 0.6m in length, to be removed (by opening the cover, taking out the bubble tray, and removing the accumulated scale) ； 2. Decide whether to remove the main agent and how much of it to remove, depending on the specific conditions of the catalyst bed ； 3. Blasting and purging of the reactor inlet pipeline ； 4. Treatment of flue dampers in the heating furnace ； 5. Open the raw material filter for cleaning and replace it with a new set of filter elements ； 6. Fill in the catalyst, protective agent, and some ceramic balls ； The construction mainly involves the reactor system; for isolation, only the reactor needs to be isolated. If it is necessary to blast and purge the pipelines in the reactor inlet section as well as the furnace tubes of the heater, it is required to open the shell-side outlet flange of heat exchanger E-101C, install a blind flange, and carry out the blasting at this location (or at the top of the reactor). 1 Requirements 1.1 Reactor isolation (1) The line from the reactor outlet to the inlet of reactor R-101 shall be isolated using a blind flange (DN250, 1 piece). (2) Isolate the outlet line of reactor R-101 with a blind flange (DN250, 1 piece). (3) Install blind plates in the appropriate locations as required (see the requirements for installing blind plates outlined in the shutdown plan). 1.2 Preparation work (1) Develop a detailed plan for removing the agent and an organizational implementation plan, and submit them to the relevant authorities for approval. (2) Before loading and unloading the catalyst in the reactor, the purging and displacement of the entire reaction system have been completed. (3) The emergency lighting in the work area should be properly installed; spare parts, rainproof tarpaulins, etc. should be brought to the site for use in emergencies. (4) Prepare the equipment needed for unloading, such as buckets, extension ladders, scales, tape measures, lighting and communication devices, catalyst lifting equipment, ventilation systems inside the reactor, isolation facilities, etc., as well as containers for storing used catalyst and ceramic balls. The personnel responsible for unloading should be equipped with protective gear (for oxygen-free operations). (5) Transport the catalysts and ceramic balls to the installation site, handle them gently, stack them in categories, and cover them with rainproof sheets if necessary for protection. The catalyst and ceramic balls need to be counted to ensure there is enough of them. At the same time, the catalysts and ceramic balls being shipped out are inspected (for the presence of factory certificates and inspection documents, to verify whether the goods match the quality inspection reports from the factory, and to check for any damage to the packaging). (6) Designate a specific person to inspect and supervise the oxygen supply, water supply, as well as communication and lighting facilities for those entering the reactor; no one shall enter the reactor to work until these facilities have been inspected and verified, and a permit for working inside the container has been issued. (7) Prepare in advance the reactor unloading and loading diagrams as well as various record forms. (8) Install the catalyst unloading and loading equipment on the top platform of the reactor. (9) Clean up the site, remove the reactor platform or any obstacles present, and keep the area clean. (10) Before opening the reactor lid, it must be ensured that the temperature inside the reactor is not greater than 60°C. (11) Construction workers with special operational qualifications, as recognized by the Mechanical Department, open the reactor cover in an oxygen-free environment and remove the diffuser and bubble tray at the top. Note: After removing the reactor cover, to prevent ferrous sulfide from catching fire spontaneously, it is necessary to promptly introduce pre-prepared special nitrogen hoses into the reactor to supply additional nitrogen. 2 Catalyst skimming 2.1 Specific steps (1) As per the skimming plan, it is necessary to remove the ceramic balls at the reactor inlet, the protective agent (1.3 tons, approximately 78 cm in length), as well as the upper 200 mm of space above the main catalyst (the exact amount of main catalyst that needs to be removed will depend on the specific circumstances). (2) The personnel responsible for removing the agent should wear protective clothing and oxygen masks, and first enter the reactor to remove the bubble distribution tray. (3) Prepare empty barrels for sorting used porcelain balls and catalysts. First, remove the porcelain balls from the top, check for any clumping, and record the removal height. (4) Calculate the discharge height of the ceramic balls, and then determine the empty height for discharging the catalyst based on whether there is caking at the top of the catalyst; if there is no caking or crushing, 200 mm of discharge distance together with the ceramic balls is sufficient ； If the caking at the top is severe, the discharge height is determined based on the situation. 2.2 Precautions: (1) Before personnel responsible for removing the agent enter the reactor, it is necessary to verify that the temperature inside the reactor is appropriate (by adding some dry ice if needed) and that the gas composition is suitable (with nitrogen protection); otherwise, entry into the reactor is strictly prohibited. (2) It is necessary to ensure the safety of the personnel responsible for removing the agent, and oxygen supply as well as first-aid measures must be properly implemented. (3) The unloaded used porcelain balls and catalysts should be managed uniformly; they must not be placed or discarded casually. (4) Organize personnel to keep accurate records of the height of the unloaded ceramic balls and catalyst. 3 Catalyst Loading 3.1 Preparatory Work for Catalyst Loading (1) Place the catalyst in barrels on the ground near the reactor; use manual labor or a forklift to transfer these barrels onto a scale for weighing and recording the weight. Then, load the catalyst into a feed hopper placed on the ground, and use a crane or electric hoist to lift this hopper up to the loading hopper at the top of the reactor. (2) The feeding funnel at the top of the reactor and the canvas feeding tube inside the reactor must be installed in advance; finally, the catalyst is fed into the reactor through the top funnel and the canvas tube. (3) The catalyst can be loaded using an electric hoist for lifting. 3.2 Catalyst Loading (1) Before loading the reactor, verify once again the loading dimensions (marks) of the ceramic balls and catalyst. (2) Use a suction device to draw the dust generated during unloading out of the reactor, thereby creating convection and ensuring a favorable environment for loading. (3) Maintain an appropriate lighting level inside the reactor for the operators to work. (4) Use a forklift to transport the catalyst in barrels to the scale for weighing; record the weight, and then load it into a feed hopper on the ground. After loading, use a crane to lift the feed hopper to the top of the reactor and unload the catalyst into the loading hopper fixed at the top of the reactor. (5) Add the catalyst and protective agent as required by the filling diagram; after adding each type of agent, level it out and take measurements. (6) Add the ceramic balls at the top of the reactor layer by layer, in accordance with the specified specifications and dimensions. After adding each type of ceramic ball, level it out, conduct inspections, and record the amount of each type of ceramic ball added. (7) Place the scale inhibitor in the top porcelain ball, and use the porcelain ball for partial filling. Then install the distribution plate and inlet distributor; once the internal components have been installed, remove any debris promptly. (8) Install the top cover of the reactor. (9) Promptly organize the quantities of various catalysts and ceramic balls of different specifications to be used. 3.3 Precautions (1) The catalyst should be handled and unloaded as gently as possible to avoid breaking it. (2) Catalyst loading should be carried out on a dry, sunny day. (3) Be careful to protect the flange surface of the reactor head and the gaskets; apply two layers of rubber protective rings on the head and the flange cover. (4) The container should be opened only before loading the catalyst. The loading process should be carried out as quickly as possible within acceptable limits, in order to reduce the time the catalyst is exposed to the atmosphere and thus minimize moisture absorption by the catalyst. (5) Catalysts that are scattered on the ground or contaminated must not be placed into the reactor. (6) Free-fall height of the catalyst during loading