NOVELTY - Penicillin sodium production waste liquid is purified and sodium is recovered by evaporating penicillin production waste liquid to evaporate extraction agent and obtain concentrated raw material liquid with sodium sulfate concentration of 40-50 g/L, adding activated carbon, adsorbing to remove impurities, performing solid-liquid separation to obtain liquid phase which is decolored solution, evaporating decolored solution to obtain concentrated decolored solution with sodium sulfate concentration of 130-150 g/L, adding alkali to adjusting pH to 7-7.5, and filtering precipitate.    USE - Purification of penicillin sodium production waste liquid and recovery of sodium sulfate (claimed).    ADVANTAGE - Purification of penicillin production waste liquid and recovery of sodium sulfate reduces protein content in penicillin wastewater, treatment difficulty, and cost, recovers pigment, organic matter, and sodium sulfate, and has small device floor area, high efficiency, and low power consumption and wastewater discharge amount.    DETAILED DESCRIPTION - Penicillin sodium production waste liquid is purified and sodium sulfate is recovered by evaporating penicillin production waste liquid to evaporate extraction agent and obtain concentrated raw material liquid with sodium sulfate concentration of 40-50 g/L, adding activated carbon, adsorbing to remove impurities, performing solid-liquid separation to obtain liquid phase which is decolored solution, evaporating decolored solution to obtain concentrated decolored solution with sodium sulfate concentration of 130-150 g/L, adding alkali to adjusting pH to 7-7.5, filtering precipitate to obtain alkali treatment solution, adding eluting agent, crystallizing, performing solid-liquid separation, recrystallizing solid to obtain high-purity sodium sulfate crystals, sending separated liquid to solvent recovery tower, recovering eluting agent, and treating tower bottom liquid in biochemical pool.    DESCRIPTION OF DRAWING(S) - The drawing shows a flowchart for the purification of penicillin production waste liquid and recovery of sodium sulfate. (Drawing includes non-English language text).