The liquefied gas inside the spherical tank contains alkali solutions/alkali residues or other substances, preventing the automatic water cut-off device from functioning properly

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In accordance with the safety inspection requirements for tank areas, automatic water cutters must be used instead of manual methods for dehydrating liquefied gas spheres. Automatic water cutters were installed as required; these devices use ultrasound to detect the oil-water interface at both high and low levels, thereby controlling the closure of the water inlet valve and the opening of the water cut-off valve. The water cutter removes water from the higher level to the lower level under low pressure. After being in use for a period of time, the water cutter stops functioning properly. Upon inspection, it was found that the liquefied gas contained certain alkaline substances, amine solutions, or alkaline residues – the exact nature of these substances is unknown. These substances remain between the water and liquid hydrocarbons inside the water cutting tank, and ultrasound cannot penetrate them (it is suspected that they are in an emulsified state). Over time, these substances accumulate in the tank and cannot return to the sphere tank, nor can they be removed from the tank, which is why the water cutter becomes ineffective. After emptying the water separation tank, waste material is discharged through the drain outlet at the bottom of the tank. In the initial stage, the discharged material is water containing certain solid impurities; it becomes clearer in the middle stage, and finally bubbles of polymer are discharged. I would like to know what this substance actually is, how such a condition arises, and whether this state also exists inside the water separator (since the pressure inside the water separator is the same as that in the tank during normal operation). The material discharged after emptying the water separator is shown in the images and videos