ABSTRACT
This chapter discusses the removal of phosphorus by chemical precipitation. It first discusses the natural occurrence of phosphorus, followed by a discussion on the modes of removal of the element. The chemical reactions of removal, unit operations of removal, chemical requirements, optimum pH range of operation, and sludge production are all discussed. The chemical precipitation method employed uses alum, lime, and the ferric salts, FeCl
and Fe
(SO
)
.
