Seek a heating and sulfidation scheme for the 6.2 MPa shift catalyst cycle method

The conversion catalyst used by our company is a cobalt-molybdenum series conversion catalyst with cobalt and molybdenum as the active components, MgO-AL2O3 as the ternary support, and non-metallic additives. The manufacturer supplies it in its oxidized state; before use, it needs to be reduced in a reactor to be sulfided, converting CoO and MoO3 into CoS and MoS2 with conversion activity, so that it can be used as an industrial catalyst. II. Basis for Compilation 1) PID diagrams from Tianchen Engineering Institute, as well as the actual construction conditions of on-site equipment and pipelines ； 2) “Specifications for Commissioning of Large and Medium-Sized Units in the Chemical Industry” ； 3) Qilu Petrochemical Keli Company provides the “QCS-01 Catalyst Operation Manual”. III. Organizational command structure: Team leader: Deputy team leader: On-site commander: Operator IV. Conditions to be met prior to vulcanization: 1) All relevant equipment and pipelines have undergone strength and airtightness tests, and have been cleaned and purged successfully. 2) All relevant control valves and check valves are properly installed and function accurately. 3) The relevant instruments and electrical systems have passed inspection, and the DCS meets the conditions for catalyst heating and vulcanization. 4) The relevant monomer commissioning has been completed. 5) The communication equipment, tools, fire-fighting, and gas protection equipment required for driving are already ready. 6) Clean up the site; in particular, flammable and explosive materials must not be left there. 7) Check the condition of the blind plates; those that are near the pumps or in areas where there is movement should be inspected carefully. 8) Verify that the surface thermometers on the converter and the thermocouples inside it have been calibrated properly, with an error of no more than 10°C, and that they are ready for use. 9) Re-check all records and files to confirm that all tasks are accurate and that the conditions for vulcanization are met. 10) Catalyst loading in the shift converter is complete, the manholes have been sealed, the shift converter is airtight, and the purging of the shift converter has been successful. The sulfidation plan has been approved, and the operators are familiar with the operating procedures and precautions. 11) Water, electricity for sulfidation, low-pressure nitrogen at 0.45 MPa, a nitrogen heating furnace, and instrument air are all available. 12) The record reports are complete, and the temperature rise curve has been drawn. 13) The temperature at the lowest point of the catalyst bed shall be ≥220°C, and the temperature difference within the catalyst bed shall be ≤50℃ ； Nitrogen flow rate at elevated temperature: 5000-20000 NM3/h ； 14) H2S at the outlet of the water scrubber ≥ 0.24%. 15) The temperature of the converter has been raised to the temperature required for sulfidation and maintained at that level for over 6 hours. V. Requirements for vulcanization: The heating and maintaining of a constant temperature in the conversion furnace must be carried out strictly in accordance with the rates specified by the manufacturer ； There is sulfur penetration at the converter outlet, and the sulfur content no longer changes; at this point, sulfidation can be considered complete. When the total sulfur content at the R2001 inlet is equal to that at the outlet, it can be considered that sulfidation of the entire system is complete; this condition should be maintained for 2 hours. VI. Steps and Methods for Sulfidation 1. Opening and closing of valves in the system process and insertion/removal of blind flanges ① Open the following blind flanges: the DN150 low-pressure nitrogen line leading to the start-up water-gas pipeline; the blind flange at the F2001 outlet of the start-up water-gas pipeline leading to R2001A/B; and the blind flange for the shifted gas at the R2001 outlet. ② Close the following valves: EV2001 and its branch lines, AV2001 and its branch lines, TV2003 and its branch lines, TV2006A/B and their branch lines, the inlet valve for water gas at E2002, the inlet valves R-2001A/B, the balance valve for the converted gas from E2002 to the heat recovery system, the two vent valves for the water gas at the outlet of E2002 that lead to the flare, the high-point vent valve on the water gas pipeline feeding F2001, the large valve leading from T2001 to the low-temperature methanol washing unit, and the drain isolation valves from each water gas separator to V2007. 2. Sulfidation route: Water gas → Water gas waste heat boiler I → First water separator → Steam superheater → Shift converter A/B → Medium-temperature heat exchanger → Shift conversion waste heat boiler → Second water separator → Medium-pressure boiler feedwater heater I → Low-pressure waste heat boiler I → Third water separator → Deionized water heater I → Shift gas water cooler → Ammonia scrubbing tower for shift converters → PV2008 → Flaring for fire suppression. 3. Method: Process gas sulfidation. (1) Determine the hydrogen sulfide content in the process gas; it is preferable that this content be ≤ 30.2% (V/V). (2) When the catalyst bed temperature reaches 200°C–220°C, the wet process gas is added to nitrogen (ratio: wet process gas:nitrogen = 1:3), and together they are fed into the start-up furnace for heating, with the reactor inlet temperature being controlled at 200°C–220°C. As the temperature of the catalyst bed increases, the flow rate of the process gas is increased, while the amount of nitrogen is reduced accordingly; when the ratio of process gas to nitrogen is 3:1, it is not advisable to increase the flow rate of the process gas any further ； Control PIC2008