Process Design Of Resource Recycling Of Non-ferrous Metallurgy Waste Acid

Non ferrous metallurgical waste acid is an inevitable pollutant in metallurgical process,it contains heavy metals,acids,suspended solids and other impurities,which harm to the environment,animals,plants and even to the human body.This project aims at the harm of colored metallurgical waste acid,and puts forward the technological scheme of recycling and reusing about waste acid.Firstly,the optimum conditions for removal of fluoride and chloride ion were determined,which used the concentration and defluorination of acid.The principle is to combine fluorine and chlorine ions with hydrogen ions and go out with the steam After experimental test,when the acid concentration was above 40%,the removal rate was above 85%.According to the process,it can be divided into four parts:The vulcanization unit,the three effect evaporation unit,the deep concentrated remove of fluoride and chlorine ions unit and the absorption unit.The vulcanization unit adopts the reaction mode of single tower batch and the whole continuous.Each tower after the reaction of liquid through the pump again to the tower and ensure the full reaction,making sure the heavy metal is settled thoroughly.The three effect evaporation unit condensed the purified acid after the vulcanization reaction to 40%,and sent it to the deep concentrated removal of fluoride and chlorine unit.The acid concentration to 60%?70%,steam as heat source of three effect evaporation.The unreacted hydrogen sulfide gas and condensate from The three effect evaporation unit generated into absorption unit for alkali absorption.After the process has been determined,the initial selection and material selection of the equipments have been done by means of calculation and HTRI software simulation,and the material energy calculations of the system were did,the final reuse of the acid content of the material can reach the standard of reuse.Then the technical and economic evaluation of the system was carried out.Compared with the traditional neutralization method,the benefit is obviously improved and the zero emission is achieved in the environment because of resource reuse.Finally,the safety problems were easily occurred,which proposed preventive and protective measures to ensure safe operation.