United States of America, as Represented by the Secretary of Agriculture

North Carolina State University

Patrick G Hunt

Matias B Vanotti

Ariel A Szogi

A process for removing phosphorus from solid poultry or animal wastes involving (a) mixing solid poultry or animal wastes with water and acid at a pH lower that about 5.0 and higher than about 3.0 to form (i) a liquid extract that contains suspended solids of about 3.5 g/L and soluble phosphorus and (ii) a washed solid residue (having a N:P ratio of at least more than 4 expressed on an elemental basis), (b) separating the liquid extract from the washed solid residue to form separated liquid extract and separated washed solid residue, (c) mixing the separated liquid extract with an alkaline earth base to a pH of about 8.0 to about 11.0, (d) mixing the liquid extract with a flocculant to form (i) precipitated phosphorus solids with POcontent greater than about 10% and (ii) a liquid, and (e) separating the precipitated phosphorus solids from the liquid to form separated phosphorus solids and separated liquid. The process is conducted at a temperature greater than about 5&#xb0; C. and less than about 50&#xb0; C. The solid poultry or animal wastes are not pretreated prior to mixing the solid poultry or animal wastes with water and acid; such pretreatments include those that may cause the complete or partial loss of oxidizable organic carbon and nitrogen.

Process for removing and recovering phosphorus from animal waste

Wastewater treatment systems and processes for: removal of solids, pathogens, nitrogen, and phosphorus from municipal and agricultural wastewater include nitrification of wastewater and increasing the pH of the nitrified wastewater by adding a metallic-containing salt and hydroxide to precipitate phosphorus to form a useable effluent having a specified nitrogen:phosphorus ratio that is useful as a fertilizer or spray for remediation of contaminated soils. The presence of infectious microorganism such as enteropathogenic bacteria and picarnoviruses will be reduced in the useable effluent. The precipitated phosphorus is recovered and used to form useable phosphorus products.

Growing community of inventors

Florence, SC, United States of America

Patrick G Hunt