The invention relates to a method for the industrial preparation of phosphoric acid from an aqueous suspension comprising water and particles of at least one phosphate material dispersed in the presence of at least one additive of the anionic polymer type. Phosphoric acid is obtained by treating this suspension with at least one strong acid. The polymer is obtained by polymerization reaction of at least one acid selected from acrylic acid, methacrylic acid and salts thereof. The invention relates to the use of this anionic polymer as well as the method for improving the rheology of the suspension and the hydrodynamics of the reaction medium in which the reactions for the manufacture of phosphoric acid take place.

The invention relates to a method for the industrial preparation of phosphoric acid from an aqueous suspension comprising water and particles of at least one phosphate material dispersed in the presence of at least one additive of the anionic polymer type. Phosphoric acid is obtained by treating this suspension with at least one strong acid. The polymer is obtained by polymerization reaction of at least one acid selected from acrylic acid, methacrylic acid and salts thereof. The invention relates to the use of this anionic polymer as well as the method for improving the rheology of the suspension and the hydrodynamics of the reaction medium in which the reactions for the manufacture of phosphoric acid take place.

In the manufacture of phosphoric acid from ore, the typical ore comprises minerals containing phosphorus and calcium along with varied amounts of other elements. Certain ores have substantial iron content which needs to be removed in order to produce quality phosphoric acid product. An improved method and associated chemical processing plant are disclosed for removing this iron. The method involves both reducing and adding oxalic acid to wet process phosphoric acid produced using an otherwise conventional manufacturing process. Iron oxalate precipitate is created which can then conveniently be separated therefrom.

In the manufacture of phosphoric acid from ore, the typical ore comprises minerals containing phosphorus and calcium along with varied amounts of other elements. Certain ores have substantial iron content which needs to be removed in order to produce quality phosphoric acid product. An improved method and associated chemical processing plant are disclosed for removing this iron. The method involves both reducing and adding oxalic acid to wet process phosphoric acid produced using an otherwise conventional manufacturing process. Iron oxalate precipitate is created which can then conveniently be separated therefrom.

A mixing tee assembly suitable for phosphate acid attack reaction is described. The mixing tee assembly comprises an outer pipe having a mixing end and a tee end, wherein a tee structure is formed near the tee end to connect with additional piping; an inner pipe comprising a nozzle end connected to a nozzle and a open end; wherein the inner pipe is lined with a corrosion-resistant material on its inside surface; wherein when the inner pipe is assembled within the outer pipe, the nozzle extends beyond the mixing end of the outer pipe by at least ⅓ of the inside diameter of the outer pipe.

A mixing tee assembly suitable for phosphate acid attack reaction is described. The mixing tee assembly comprises an outer pipe having a mixing end and a tee end, wherein a tee structure is formed near the tee end to connect with additional piping; an inner pipe comprising a nozzle end connected to a nozzle and a open end; wherein the inner pipe is lined with a corrosion-resistant material on its inside surface; wherein when the inner pipe is assembled within the outer pipe, the nozzle extends beyond the mixing end of the outer pipe by at least ⅓ of the inside diameter of the outer pipe.

Methods for removing heavy metals from a phosphoric acid solution produced in a wet process for manufacturing phosphoric acid, comprising treating the wet-process phosphoric acid solution with a small amount of a solid adsorbing material and a complex reagent to form a heavy metal complex-contaminated solid adsorbing material, and removing the contaminated solid adsorbing material to yield a treated phosphoric acid solution having a low heavy metal content.

Methods for removing heavy metals from a phosphoric acid solution produced in a wet process for manufacturing phosphoric acid, comprising treating the wet-process phosphoric acid solution with a small amount of a solid adsorbing material and a complex reagent to form a heavy metal complex-contaminated solid adsorbing material, and removing the contaminated solid adsorbing material to yield a treated phosphoric acid solution having a low heavy metal content.

An agitator or mixer installed in a solid-liquid-gas/slurry reactor in which gas removal from the slurry and foam destruction is promoted. The reaction mixer includes a vessel and an agitator assembly. The vessel is for containing the solid-liquid-gas mixture and defines two mixing zones within a given volume; a first mixing zone and a second mixing zone located above the first mixing zone. The agitator assembly is positionable within the vessel and comprises a rotatable shaft and a first and second impeller coupled to the shaft. The first axial impeller is locatable within the first mixing zone and is configured to pump the liquid in a downward direction along a vertical axis of rotation. The second impeller is locatable within the second fluxing zone and is configured to pump the liquid in an upward direction along the vertical axis of rotation.

Process for recovering phosphorus from ashes coming from combustion plants that are fed with renewables and/or waste materials as solid fuel, comprising a phase of mixing said ashes coming from combustion plants that are fed with renewables and/or waste materials as solid fuel with a sulfuric acid solution, in order to extract the phosphorus therein contained; a system for carrying out said process is also described.