Liquid or solid sulfur is fed into pipelines insulated with steam coils and jackets, then delivered to the sulfur melting tank. The molten sulfur is subsequently pumped to the high-level tank and further conveyed to the sulfur burner by a submerged gear pump or a gear pump with steam-jacket insulation. By integrating a mass flow meter with a variable-frequency drive (VFD) on the gear pump, the flow rate of liquid sulfur is maintained at a stable and controlled rate.   Features: The WEIXIAN liquid sulfur gear pump resists clogging by impurities. With the flow rate regulated by a mass flow meter and VFD, delivery is stable and accurate. The system also enables online monitoring of operating parameters, offering maximum convenience for controlling SO₃ concentration, adjusting plant performance, and switching product grades.