The present invention relates to a chemical phosphoric acid production unit, comprising: a reactor for the production of phosphoric acid, a receiving device (2) for receiving phosphogypsum obtained after filtration of phosphoric acid produced in the reactor, a discharge system (1) for discharging phosphogypsum from the receiving device (2).

The chemical unit is mainly characterised in that the discharge system (1) comprises a chute (3) of which the inlet (4) is located inside the receiving device (2) and is arranged so as to communicate with said receiving device (2), and a flap (6) moveable around an axis of rotation (7), said flap (6) being able to open according to a predetermined angle () corresponding to a predetermined section (13) for the passage of a fraction of phosphogypsum through the inlet (4) of the chute (3), and to close in order to prevent the passage of phosphogypsum into the chute.

The present invention relates to a chemical phosphoric acid production unit, comprising: a reactor for the production of phosphoric acid, a receiving device (2) for receiving phosphogypsum obtained after filtration of phosphoric acid produced in the reactor, a discharge system (1) for discharging phosphogypsum from the receiving device (2).

The chemical unit is mainly characterised in that the discharge system (1) comprises a chute (3) of which the inlet (4) is located inside the receiving device (2) and is arranged so as to communicate with said receiving device (2), and a flap (6) moveable around an axis of rotation (7), said flap (6) being able to open according to a predetermined angle () corresponding to a predetermined section (13) for the passage of a fraction of phosphogypsum through the inlet (4) of the chute (3), and to close in order to prevent the passage of phosphogypsum into the chute.

A process for recovering phosphorus from phosphoritic materials in a top submerged lance furnace or a fuming furnace is disclosed. The process employs a mixture of combustion agents to produce reducing conditions in the slag bath and post-combustion oxidising conditions in the headspace of the furnace. The process involves smelting a mixture of a phosphoritic material and a carbonaceous material in the furnace to produce a molten slag in the slag bath and phosphorus vapour in the headspace, wherein the post-combustion oxidising conditions in the headspace favours retention of ferrous oxides in the molten slag to minimise deportment of phosphorus to a ferro-phosphorus alloy; The phosphorus vapour in the headspace is subsequently oxidised to produce phosphorus pentoxide, which is subsequently passed from the headspace to a reactor to recover a phosphoric acid solution.

A process for recovering phosphorus from phosphoritic materials in a top submerged lance furnace or a fuming furnace is disclosed. The process employs a mixture of combustion agents to produce reducing conditions in the slag bath and post-combustion oxidising conditions in the headspace of the furnace. The process involves smelting a mixture of a phosphoritic material and a carbonaceous material in the furnace to produce a molten slag in the slag bath and phosphorus vapour in the headspace, wherein the post-combustion oxidising conditions in the headspace favours retention of ferrous oxides in the molten slag to minimise deportment of phosphorus to a ferro-phosphorus alloy; The phosphorus vapour in the headspace is subsequently oxidised to produce phosphorus pentoxide, which is subsequently passed from the headspace to a reactor to recover a phosphoric acid solution.

A substrate treating apparatus includes a circulating line having a treating tank for storing a phosphoric acid aqueous solution, a circulating pump for feeding the phosphoric acid aqueous solution, a heater for circulation for heating the phosphoric acid aqueous solution, a filter for filtering the phosphoric acid aqueous solution, the circulating line causing the phosphoric acid aqueous solution discharged from the treating tank to flow in order of the circulating pump, the heater for circulation and the filter, and returning the phosphoric acid aqueous solution from the filter to the treating tank. The apparatus also includes a branch pipe branching from the circulating line between the heater for circulation and the filter for extracting the phosphoric acid aqueous solution from the circulating line, and a concentration measuring station connected to the branch pipe for measuring silicon concentration in the phosphoric acid aqueous solution by potentiometry.

A substrate treating apparatus includes a circulating line having a treating tank for storing a phosphoric acid aqueous solution, a circulating pump for feeding the phosphoric acid aqueous solution, a heater for circulation for heating the phosphoric acid aqueous solution, a filter for filtering the phosphoric acid aqueous solution, the circulating line causing the phosphoric acid aqueous solution discharged from the treating tank to flow in order of the circulating pump, the heater for circulation and the filter, and returning the phosphoric acid aqueous solution from the filter to the treating tank. The apparatus also includes a branch pipe branching from the circulating line between the heater for circulation and the filter for extracting the phosphoric acid aqueous solution from the circulating line, and a concentration measuring station connected to the branch pipe for measuring silicon concentration in the phosphoric acid aqueous solution by potentiometry.

It is introduced that a device of manufacturing lithium sulfate comprising: a reaction body in which a reaction of lithium phosphate and sulfuric acid is performed, the reaction body being divided into an upper space and a lower space; a pressurizer for applying pressure to the inside of the reaction body; a stirrer disposed in the upper space for stirring the lithium phosphate and sulfuric acid to produce a mixture containing lithium sulfate and phosphoric acid; and a filter disposed inside the reaction body and separating the filtrate containing the phosphoric acid into the lower space by filtering the mixture.

Embodiments described herein provide systems and methods for a phosphate processing system with integrated sub-systems, such as a phosphoric acid plant, precipitation system, crystallizer system, rinsing system, granulation system, pond water system, organics removal system, and/or exhaust treatment system. Such sub-systems can be integrated with each other by using one or more output streams from one or more sub-systems as one or more input streams for one or more sub-systems. In some embodiments, the phosphate processing system can produce phosphoric acid, struvite containing fertilizer, fertilizer using recycled struvite, magnesium or fluoride containing compositions using recycled magnesium or fluoride, and other components using phosphoric acid collected from a phosphoric acid and gypsum composition or using sludge collected from a waste stream, for example.

Disclosed is a composite pellet used as a raw material in a kiln process for the production of phosphoric acid, which is of a core-shell structure with an inner ball encapsulated with a shell, the inner ball mainly consists of a inner ball material and a binding agent, and the shell mainly consists of a cladding material and a binding agent; the inner ball material mainly consists of a carbonaceous reductant powder, and phosphate ore powder and silica powder, the inner ball is combined with the shell through the binding agent to form the core-shell shaped structure. The preparation of the composite pellets comprises the steps of preparing the inner ball, preparing the cladding material, forming, drying and solidifying composite green pellets etc. The composite pellets prepared by the present invention have a smaller range of formulation fluctuation, more stable quality, higher strength and better performance.

Disclosed is a composite pellet used as a raw material in a kiln process for the production of phosphoric acid, which is of a core-shell structure with an inner ball encapsulated with a shell, the inner ball mainly consists of a inner ball material and a binding agent, and the shell mainly consists of a cladding material and a binding agent; the inner ball material mainly consists of a carbonaceous reductant powder, and phosphate ore powder and silica powder, the inner ball is combined with the shell through the binding agent to form the core-shell shaped structure. The preparation of the composite pellets comprises the steps of preparing the inner ball, preparing the cladding material, forming, drying and solidifying composite green pellets etc. The composite pellets prepared by the present invention have a smaller range of formulation fluctuation, more stable quality, higher strength and better performance.