A liquid separator
system having a
gas phase zone, an aqueous phase zone and a denser liquid zone is used to separate mixtures of fluids. The separator can be used for separating molten
sulfur from liquid
redox solution or reslurry water. The
system includes a vessel with a top part and a bottom part. The vessel has a larger
diameter at the top part than at the bottom part. The
system also includes an inlet for introducing a
redox solution or reslurry water and molten
sulfur, which is denser than
redox solution or reslurry water, into the vessel. An outlet near the bottom part of the vessel allows a flow of the molten
sulfur from the vessel. An interface control structure senses an interface level between the redox solution or reslurry water and the molten sulfur, and the interface control structure controls the flow of molten sulfur from the outlet. The interface control structure is adjusted to optimally alter the vertical height of the interface level within the vessel so that the
residence time of the molten sulfur in the vessel does not decrease as the sulfur production
throughput decreases, and so that the interface area of the molten sulfur and the redox solution is reduced as the sulfur
throughput decreases. A
pressure controller monitors the pressure in the vessel and adds or removes gas from a
gas phase zone in the vessel to maintain a predetermined pressure regardless of the vertical height of the interface.