Treatment method of ferrous waste hydrochloric acid

• Main Authors: WANG ZHENPING, ZHAO MING, YU XUEFENG, LIU HUAN
• Format: Patent
• Language: English
• Published: 12.08.2015
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; CLEANING OR DEGREASING OF METALLIC MATERIAL BY CHEMICALMETHODS OTHER THAN ELECTROLYSIS; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; COMPOUNDS THEREOF; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

The invention provides a treatment method of ferrous waste hydrochloric acid. The method comprises the following steps: (1) enabling the ferrous waste hydrochloric acid to react with plenty of scrap iron until complete solute in the solution is ferrite ferrous chloride; (2) concentrating and crystallizing the ferrous chloride solution obtained from the step (1) through a multi-stage vacuum distillation device and a single-stage vacuum distillation device, so as to obtain a ferrous chloride crystal; (3) calcining the ferrous chloride crystal obtained from the step (2) through a rotary kiln, decomposing to obtain hydrogen chloride gas, water vapor and a ferric oxide solid, collecting the ferric oxide solid to obtain a ferric oxide product, and exhausting mixed gas containing the hydrogen chloride gas, the water vapor, a little of ferric oxide dust and combustion tail gas; and (4) cooling the mixed gas obtained from the step (3) through a heat exchanger to form hydrochloric acid droplets.