ABSTRACT
This chapter illustrates the theory for precipitation–crystallization technology. It discusses important control measure that leads to the success in the technology, and presents a detailed study of the technology for lead removal. The chapter provides several important case studies to further illustrate the technology. The surface precipitation plays a key role in the operation of the treatment system, which is illustrated in the precipitation–crystallization for lead ion removal. Crystallization is the result of three processes: crystal nucleation, crystal growth, and secondary changes in the resulting crystal suspension by such mechanisms as agglomeration, aging, and recrystallization. In addition, the researchers developed a mathematical model for the calcium phosphate precipitation–crystallization system. The multistage system included a bioreactor to oxidize ferrous iron, an fluidized bed reactor for the precipitation of ferric iron as a coating media, and a carbonate bed for the pH adjustment/control. Zhou and co-workers developed a precipitation–crystallization process for removing copper, nickel, and zinc from industrial wastewater.
