关键词: 炼油装置, 锅炉汽包, 液位测量, 平衡容器, 电容液位计

Abstract: The accurate measurement of boiler drum liquid level and the prevention of liquid level exceeding the limit are important prerequisites to ensure the stable operation of the boiler and affect the safety of the device. The balance vessel type differential pressure liquid level gauge is often used to measure the boiler drum liquid level in oil refining unit. Based on the measurement principle of the balance vessel and the physical characteristics of saturated water and saturated steam in the boiler drum, the defects of the balance vessel that is easily affected by the ambient temperature and cannot be measured under all working conditions are analyzed. This paper introduces the measuring principle of multi-stage capacitance level gauge. From the point of view of preventing common cause failure of similar instruments, it is suggested that the multi-stage capacitive liquid level gauge with automatic compensation function be used as an effective supplementary means for boiler drum liquid level measurement in oil refining unit.

Key words: oil refining unit, boiler drum, liquid level measurement, balance vessel, capacitance level gauge