I would like to ask, how can sulfur buildup in various parts of the pipeline be resolved? Reason?

Could the original poster be more specific? In which pipes of which sections is sulfur present? Is it the sulfur recovery section? The liquid sulfur pipelines in the sulfur recovery section are steam-heated to prevent sulfur from condensing.

Found in various locations such as CO2 and O2 pipelines in coal chemical industries

If there is low-pressure steam, it can be purged.

Use steam to blow through the pipeline or apply pipeline heating for insulation in order to facilitate dissolution

So what is an appropriate temperature for the condensed steam?

Solid sulfur: specific gravity: 2.046 t/m3, melting point: 120°C, boiling point: 444.6°C, critical point: 1041°C, specific heat: 0.71 J/g·K, heat of fusion: 1.7175 Kj/mol, heat transfer coefficient: 0.00269 W/cm·K, heat of combustion: 2.241 Kcal/g (solid monoclinic) and 2.221 Kcal/g (solid orthorhombic); heat of atomization: 279 Kj/mol. Temperature (°C), Sulfur form, Density (KG/M3), Relative density (%), Relative volume (%)
Greater than 114.5: Liquid, 1799, 100, 100
114.5: Amorphous solid sulfur (γ-sulfur), 1920, 106.7, 93.7
114.5–95.5: Monoclinic solid sulfur (β-sulfur) (melting point 119°C), 1960, 108.9, 91.8
Less than 95.5: Orthorhombic solid sulfur (α-sulfur) (melting point 112.8°C), 2070, 115.1, 86.9
Therefore, using steam at a pressure of 0.3 MPa is generally sufficient. You had better consider the thermal expansion of your pipeline.