Abstract: Traditional oxygen lance nozzles for electric arc furnace (EAF) employ conventional conical designs, which severely constrain particle acceleration and focusing during supersonic gas–solid jet (SGSJ) operations, ultimately resulting in a weak gas–solid jet. To address these limitations and enhance the impact force of EAF oxygen lances, three nozzle profile designs for the Raoult nozzle are investigated. The objective is to optimize the phosphorus removal kinetics in the molten pool by modifying the oxygen jet morphology and lime powder injection method. Through numerical simulation, an SGSJ model was established for three distinct nozzle profiles (Conical Line, Vitosinski curve, and Bicubic curve). This revealed the interaction mechanisms between gas and solid phases within the supersonic jet under different nozzle geometries, yielding the following results: (1) The double-cubic-curve nozzle (Nozzle 1) formed a stable jet core region, exhibiting superior gas acceleration performance and flow stability compared to the other two nozzles; (2) The smooth streamlined design optimized energy exchange between the gas and solid phases. Nozzle 1 achieved the highest average particle velocity at the outlet, indicating superior momentum transfer efficiency and particle acceleration capability; (3) Nozzle 1 exhibits stronger vorticity and shear effects within the flow channel, with significant velocity slip between gas and solid phases. In contrast, the conical nozzle (Nozzle 3) experiences energy loss and premature particle velocity decay due to abrupt geometric changes; (4) Nozzle 1 delivers superior initial acceleration, core flow stability, and overall jet quality, though particle velocity decay at the jet’s trailing edge occurs faster than in Nozzle 3. Overall, the double-quadratic nozzle outperforms other designs in achieving efficient gas acceleration, maximizing initial particle kinetic energy, and ensuring core flow stability.