Questions about sphere tank level?
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Could someone with expertise in storage and transportation give some advice regarding high liquid levels in spherical tanks? The liquid levels in the two newly put into service propylene storage tanks do not match the actual inventory levels. Here’s what’s happening: 3,000 tons of propylene were sent to these tanks from the upstream manufacturer, and the liquid level readings indicate that the total amount in the tanks is 2,300 tons. In reality, 600 tons of propylene were delivered, so the actual inventory should be 2,300 + 600 = 2,900 tons. This is 100 tons less than the 3,000 tons stated by the upstream manufacturer. I’m not sure where the discrepancy comes from; checks on the servo-level gauges in the tanks suggest that such a large error shouldn’t occur. Could anyone please offer some suggestions?
I’m wondering why a mass flow meter isn’t used to calculate the inflow and outflow
When the temperature of propylene changes, both its volume and density change
Can volume and density change by so much? Is the servo level gauge broken?
Not all 3,000 tons will be unloaded; some will remain in the storage tanks. Has this been taken into consideration?
The original poster did not take into account the errors caused by density; temperature compensation is necessary. Our factory uses differential transformers to measure liquid levels, and changes in the density of the raw materials have a significant impact on the liquid level as well
The method of measuring mass using liquid level is no longer used in many factories. Measured with a mass flow meter, with temperature and pressure compensation, and the data is fed into a computer. Mass flow meters are used for both feeding and discharging. Moreover, it is necessary to consider whether the measurement method used by upstream manufacturers is accurate. The measurement system error of upstream manufacturers will result in a positive error.
There are mainly two types of issues: 1. Trade measurement requires high precision, which is usually achieved using high-precision flow meters or weighing methods, such as mass flow meters. The ball tank level gauge is primarily used for auxiliary monitoring only, and cannot serve as the main means or method for measurement. 2. What type of level gauge is used for the spherical tank, and does its accuracy meet the requirements? Has it been regularly calibrated?