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Steam was generated in the catalytic steam generation system of a refinery, with the pressure reaching 3.7 Mpa; the steam drum was on the verge of overpressure, and it was necessary to integrate this steam into the system. At that time, the pressure in the system was 1.7 Mpa. The rapid integration led to a large amount of water being carried along with the steam, causing critical equipment downstream to stop operating (problems arose with the turbine). My analysis of this issue is as follows: 1. The catalytic drum is at a saturated state at 3.7 Mpa at this time, with a saturation temperature of 246°C; when it is suddenly connected to a system at 1.7 Mpa, the pressure drops sharply, causing the water in the drum to become supersaturated and vaporize rapidly. The saturation temperature of 1.7Mpa steam is 204°C. The water in the 3.7Mpa drum is severely supersaturated, with a supersaturation temperature difference of 42°C; this leads to rapid expansion, causing the drum’s liquid level to rise sharply, potentially reaching full capacity, and allowing large amounts of water to enter the system along with the steam. Once the boiler water has vaporized, the liquid level in the drum drops sharply, resulting in an inability to supply enough water and a decrease in the pressure of the feed water pump. This is the main reason for the problem. By checking the trends in drum pressure and liquid level, the issue will become clear. 2. Since the steam supply from the power boiler cannot ensure the operation of the catalytic condensing compressor, in order for the catalytic unit to operate, the steam generated by it must be superheated in a waste heat boiler before being fed into the medium-pressure steam system. At this time, the waste heat boiler should be connected to the system (either by opening the bypass valve or by ensuring that the main valve is open to a certain degree). The advantages of this approach are as follows: 1) The operating pressure of the catalytic steam drum is consistent with that of the system, which prevents large pressure differences from occurring. In this case, there are two separate pressure systems – the power steam pressure system is under control, while the pressure of the steam generated by the catalytic unit is not properly controlled; moreover, since the steam has no outlet and no venting mechanism, it inevitably increases the operational difficulties and risks associated with the catalytic steam drum. Only in this way can the problem of a blocked catalytic backpath be avoided. Only in this way can the problem of severely insufficient system steam pressure be avoided. 2) Steam passes through the spare furnace, which serves as a form of protection for the furnace tubes. At this time, by adjusting the flue gas bypass and main control valves, it is possible to ensure that the steam generated in the catalytic drum is superheated in the spare furnace to become superheated steam free of water. 3) The system is in a continuous flow state, which reduces the accumulation of condensate water between the catalytic steam drum and the waste heat boiler. 4) The temperatures on the steam and flue gas sides of the waste heat boiler can be controlled by adjusting the opening degrees of the flue gas dampers in the bypass and main circuits of the waste heat boiler. This company is in a special situation: the saturated steam generated by catalysis is not incorporated into the system, and medium-pressure steam cannot ensure the operation of the turbines in condensing steam turbine units. Therefore, the operation of removing the waste heat boiler from the system also presents problems (I personally am against removing the waste heat boiler; doing so increases the workload and makes system operation more difficult. Moreover, it must be reconnected to the system in order to ensure an adequate supply of steam for catalyst operation). Everyone, let’s discuss. Clarifying the discussion can prevent it from happening again.