Disposal of Spent Phosphorus Sorption Materials

Abstract

This chapter discusses the disposal options for the spent PSMs after they have achieved their useful lifetime in a P removal structure. This includes (1) use of the spent PSMs as a soil P fertilizer, (2) use as a plant growth media, (3) assessing P availability in the spent PSMs, (4) potential P stripping from the PSMs and recharge, (5) land application of spent PSMs for purposes other than P fertility, (6) non-plant use of spent PSMs, and (6) safety considerations in beneficial re-use of spent PSMs. The majority of this discussion is on the land application of PSMs to soils, and any potential benefit that that the PSMs may have on soil quality and plant growth. The potential beneficial re-use of spent PSMs strongly depends on how stable the PSM-bound P is, and forms of P contained on it. A discussion on the economics of P-stripping and PSM regeneration is also included. Several tables consisting of safety characterization data from various by-product PSMs are shown.