Removal of Heavy Metal Ions from Industrial Wastewater Based on Chemical Precipitation Method

With the acceleration of urbanization and the rapid development of industry and agriculture, a large number of industrial wastewater containing heavy metal is produced. Heavy metal ions are not easily degraded and are highly harmful. Removal of heavy metal ions in industrial wastewater is the main way to reuse wastewater. The method for removing heavy metal ions from industrial wastewater based on chemical precipitation method is proposed in this paper, which utilizes instruments and reagents to fuse metal ion solution and industrial wastewater by preparing heavy metal ion solution, industrial wastewater and adsorbent. Calcium hydroxide is placed in the industrial wastewater solution to cause the direct chemical reaction with the heavy metal ions therein. Through a series of processes such as decomplexation reaction, sedimentation, and detection of heavy metal ion concentration, the precipitate that is hardly soluble in water is finally formed, and it is absorbed by the biofilm adsorbent. The experimental results show that pH value, reaction time, adsorbent dosage and initial concentration of metal ions have great influence on the proposed method. The removal ability of heavy metal ions can be improved by adjusting the influencing factors, which provides the theoretical basis for practical application of heavy metal industrial wastewater.