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During the conversion reaction, at a constant temperature, the higher the reaction activation energy, the faster the reaction rate; the higher the pressure, the faster the reaction rate; the higher the catalyst activity, the faster the reaction rate. Fill in: ‘Slower, Faster, Unchanged’. The main catalyst in the hydrogenation reactor is ( ), the conversion catalyst is ( ), and the medium-conversion catalyst is ( ). During the conversion reaction, excessive fluctuations in the water-to-carbon ratio, along with a sudden decrease in the amount of water vapor, can cause ( ). The negative pressure in the furnace has a significant impact on the combustion efficiency of the converter; the lower the negative pressure, the greater the amount of residual air in the furnace, and thus the higher the thermal efficiency of the converter. The negative pressure in the converter furnace chamber is controlled at ( ). Minor carbon deposition on the converter tubes can be removed by ( ). After an emergency shutdown, to prevent carbon deposition, it is necessary to replace ( ) promptly. The drum blowdown is divided into ( ) blowdown, also known as continuous blowdown, which is mainly used to remove ( ) ； Adjust the steam quality, reduce the salt content in the steam, and prevent the formation of ( ) in the steam drum. The drum ( ) drainage, also known as top discharge, is primarily used to remove substances from the drum ( ). Soda water azeotrope phenomenon: The liquid level indicated by the drum level gauge fluctuates violently, making it difficult to determine the actual level; in some cases, there may even be steam pipeline () phenomena, and the temperature of the conversion catalyst bed () – in severe cases, this can lead to damage to the catalyst (). Combustion control of the converter burner: the flame shape should be (), the flame length must be controlled at (), to prevent () phenomena and extend the service life of the converter tubes. The flame length in the converter furnace should be kept as consistent as possible; the furnace temperature is ( ), and the color of the furnace flame is ( ). When the conversion reactor tubes suffer from severe carbon deposition, the resistance of these tubes increases, while the surface temperature of the tubes rises; in some cases, red spots or a red color on the tube surface may appear. To increase the conversion rate of the conversion reaction, it is possible to raise the ( ) of the reaction – temperature, pressure, or the water-carbon ratio. To increase the rate of the conversion reaction, it is possible to increase the ( ) of the reaction – pressure, the water-carbon ratio, or the hydrogen concentration. The zinc oxide reaction is a ( ) phase reaction. Gas-liquid phase B, liquid-solid phase C, gas-solid phase. The blower and exhaust fan are started to create a negative pressure in the furnace of -1 to -5 mm of water column; the negative pressure in the conversion furnace refers to the pressure in the () section of the conversion furnace. For the upper section B, middle section C, and lower section, the nitrogen circulation in the converter is used to raise the temperature; steam is only added once the specified temperature is reached, and this temperature is determined by ( ). A. The specified temperature in the process workshop B. The saturation steam temperature at that pressure C. Furnace temperature 6. The main mode of heat transfer in the converter furnace is ( ) A. Radiation B. Conduction C. Convection 7. The reason why the burner mouth turns red is ( ) A. Small primary and secondary air valves B. Low pressure of the fuel gas C. Clogged burner 8. The reason for installing a flame arrester at the high-point vent of PSA3 is ( ) A. To prevent flames from returning into the process pipelines B. To filter out mechanical impurities and avoid dust pollution of the environment C. To prevent flames from being generated during the discharge of process gas The outlet temperature of the converter furnace and the fuel gas pressure are regulated by PIC61419 in a cascade configuration; this temperature sensing point is located at ( ) A. Upper part of the furnace B. Lower part of the furnace C. Gas collection duct The furnace temperature in the converter furnace does not change much, while the temperature in the convection section rises. This is mainly due to ( ) A. Complete combustion of the fuel gas in the furnace B. Insufficient air in the furnace C. Secondary combustion in the convection section of the converter furnace 11. Wear ( ) when working with dust. A Cotton gauze mask B Filtered dust mask C Gas mask 12. Persons suffering from ( ) diseases shall not engage in dust-exposed work. A. Active pulmonary tuberculosis B. Chronic cholecystitis C. Fatty liver 13. The factors that do not influence the development of silicosis are ( ). A. Content of free silica B. Dust concentration C. Personal preferences. 14. Among the 13 legally recognized pneumoconiosis diseases in China, which one poses the most serious health risks? A. Cotton and linen dust disease B. Grain dust disease C. Silicosis. 15. The condition under which a low-pressure container containing media with an extremely high or high degree of toxicity is classified as category three is ( ). A. PV≥0.2MPa B. PV≥0.5MPa C. PV≥10MPa. III. True or False questions (1 point per question, total 10 points). 1. The raw materials for hydrogen production consist of dry distillation gas, coke oven gas, low-decomposition gas, and natural gas; when the temperature of the conversion furnace remains constant and the flow rate of the process gas stays unchanged, the amount of hydrogen produced also remains unchanged. ( ) 2. The raw gas processed by the advanced desulfurization tower is considered qualified when its sulfur content is less than 0.1 PPm. ( ) 3. The process requirement is that the CO content at the outlet of the variable-reactor should be <3 (V)%. ( ) 4. Process parameters for deionized water: conductivity ≤0.2 μs/cm, hardness ≤2 μMol/L, iron ≤2 μg/Kg, copper ≤5 μg/Kg, pH=8.8–9.3, chloride ions <5 mg/L, oil content <0.3 mg/L. ( ) 5. Process parameters for 3.5 Mpa steam: temperature ≥249°C, pressure ≥3.5 Mpa; iron ≤20 μg/Kg, copper ≤5 μg/Kg, sodium ≤15 μg/Kg, SiO2 ≤20 μg/Kg. ( ) In hydrogen production, once there is a disruption in the supply of feed material and steam is introduced alone, causing oxidation of the catalyst, the temperature used for hydrogen reduction should be higher than the temperature used during oxidation. ( ) 7. A centrifugal pump is mainly composed of an impeller, shaft, suction chamber, volute, shaft seal box, and mouth ring. （ ） 8. When the centrifugal pump is in standby mode, there is no need to rotate it frequently. ( ) 9. When using a centrifugal pump, attention should be paid to the oil level in the oil tank; the oil level should be kept within the range of 1/2 to 2/3 when refilling oil. ( ) 10. When shutting down a centrifugal pump, first turn off the motor, and then close the outlet valve. （ ） IV. Term Explanations (3 points per question, 15 points in total) 1. Hydrogen corrosion: Hydrogen embrittlement: Compression ratio: 4. Continuous sewage discharge: Catalyst poisoning: Short-answer questions (20 points in total) Briefly describe the procedures for handling an outage of a single raw gas compressor (7 points). Briefly explain the causes and symptoms of sulfur poisoning in conversion catalysts (3 points). Describe the measures to take when the amount of steam used in startup decreases during the commissioning process (10 points)