Urgent question: What aspects does the control loop for this position involve?
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The Human Resources Department organized an important exam, and the workshop provided a syllabus; one of the requirements was to describe the control circuits for one’s own position. Our workshop is equipped with a 5000 NM3/H dry gas hydrogen production unit, and the design of such units is roughly similar. Could those who have experience explain this to us?
Generally, you are expected to answer regarding the important and distinctive control loops of this device, such as the water-to-carbon ratio proportional control loop, the cascade control loop for selecting the outlet temperature of the converter, and the three-element control loop for the steam drum. Additionally, the program control of PSA can also be included. If it’s a fill-in-the-blank question, this is roughly the right way to answer it; in simple cases, it’s necessary to briefly explain the control principle and its function. For example, a cascade control loop is used for regulating the outlet temperature of the converter. The converter uses two types of fuel: PSA purge gas (primary) and system fuel gas (secondary). During startup and shutdown, system fuel gas is used as the fuel, while during normal operation, PSA purge gas serves as the primary fuel with system fuel gas used as a supplement. In both cases, control is achieved by linking the outlet temperature of the converter to the pressure (flow rate) of the system fuel gas.