Issues with the pressure gauge in the slurry coal gasification lockhopper

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There are several pressure and differential pressure gauges on the slurry gasification lockhopper, used to measure the pressure in the lockhopper as well as the pressure difference between the gasifier and the lockhopper. However, I remember that in Texaco’s previous design, two gauges were used to measure the pressure in the lockhopper, while one gauge was used for measuring the pressure difference. However, currently, the designs of most plants use only one gauge to measure the lockhopper pressure. Please discuss whether this approach is appropriate Let me share my own opinion first: I think doing this is inappropriate. Since the lock-hammer pressure fluctuates periodically, it is around 6.5 MPa at high pressure and 0.2 MPa at low pressure; in both cases, a certain level of measurement accuracy is required. For a pressure gauge, its measurement accuracy is best at around 2/3 of its range; in other words, it has higher accuracy either at high pressures or at low pressures, and it is not possible to maintain high accuracy at both extremes. Therefore, it is better to use two gauges in order to measure the pressure in the lockhopper.