JPWO2019030403A5

JPWO2019030403A5 -

Info

Publication number: JPWO2019030403A5
Application number: JP2020506971A
Authority: JP
Publication date: 2022-11-22
Anticipated expiration: 2038-08-10

Description

この問題を解決するために、本発明は、冒頭で述べたような精製されたリン酸塩系の化合物の生成のためのカルシウムを含むリン酸塩源の酸攻撃のプロセスに関し、
ａ）第１の固形物と、第１の固形物が懸濁している第１の液相とを含む第１の懸濁液の形成を伴う、２０～１８０分の範囲の所定の期間におけるこのリン酸塩源の硫酸による酸攻撃工程であって、この第１の固形物が少なくとも硫酸カルシウム及び不純物を含み、この第１の液相がリン酸及び溶解したリン酸一カルシウムを含み、この攻撃は、硫酸から及び場合によりリン酸塩源からの硫酸塩とカルシウムとのモル比が０．６～０．８の間で含まれ、Ｐ_２Ｏ_５の含有量が６％未満である投入条件で行われる、酸攻撃工程と、
－ｂ）この第１の液相からのこの第１の固形物の分離を伴うこの第１のスラリーの第１の濾過工程と、
－ｃ）精製されたリン酸塩系の化合物のこの第１の液相からの回収工程と
を含む。
In order to solve this problem, the present invention relates to a process of acid attack of calcium-containing phosphate sources for the production of purified phosphate-based compounds as mentioned in the introduction,
a) this over a period of time ranging from 20 to 180 minutes with the formation of a first suspension comprising a first solid and a first liquid phase in which the first solid is suspended; a step of acid attacking a phosphate source with sulfuric acid, the first solid comprising at least calcium sulfate and impurities, the first liquid phase comprising phosphoric acid and dissolved monocalcium phosphate, the attack is a dosage condition in which the molar ratio of sulfate to calcium from sulfuric acid and optionally from a phosphate source is comprised between 0.6 and 0.8 and the content of P ₂ O ₅ is less than 6% an acid attack step carried out in
-b) a first filtration step of said first slurry with separation of said first solids from said first liquid phase;
-c) recovering the purified phosphate-based compound from this first liquid phase.

有利には、本発明によるプロセスは、
－第１の固形物及び第１の液相を含む第１の懸濁液の形成を伴う、２０～１８０分の範囲の所定の期間における、リン酸塩源の硫酸による１つ、２つ又は複数の攻撃タンクでの酸攻撃であって、第１の固形物は懸濁液中にあり、第１の固形物は少なくとも硫酸カルシウム及び不純物を含み、この第１の液相はリン酸及び溶解したリン酸一カルシウムを含み、この攻撃は、硫酸から及び場合により硫酸塩源からの硫酸塩とリン酸塩源中に存在するカルシウムとのモル比は０．６～０．８の間に含まれ、１つ又は複数の攻撃タンクのＰ_２Ｏ_５含有量は６％未満である投入条件で行われる、攻撃工程と、
－この第１の液相からのこの第１の固形物の分離を伴うこの第１のスラリーの第１の濾過工程と、
－精製されたリン酸塩系の化合物のこの第１の液相からの回収工程と
を含む。
Advantageously, the process according to the invention comprises
- with sulfuric acid of the phosphate source one, two or for a predetermined period of time ranging from 20 to 180 minutes with the formation of a first suspension comprising a first solid and a first liquid phase Acid attack in a plurality of attack tanks, the first solids being in suspension, the first solids comprising at least calcium sulfate and impurities, the first liquid phase comprising phosphoric acid and dissolved monocalcium phosphate, wherein the attack comprises a molar ratio of sulfate from the sulfuric acid and optionally from the sulfate source to calcium present in the phosphate source between 0.6 and 0.8. and _the attack step is carried out at charging conditions in which the _P2O5 content of the one or more attack tanks is less than 6%;
- a first filtration step of said first slurry with separation of said first solids from said first liquid phase;
- recovering the purified phosphate-based compound from this first liquid phase.

有利には、本発明によるプロセスは、
－第１の固形物及び第１の液相を含む第１の懸濁液の形成を伴う、２０～１８０分の範囲の所定の期間における、リン酸塩源の硫酸による１つ、２つ又は複数の攻撃タンクでの酸攻撃であって、第１の固形物は懸濁液中にあり、第１の固形物は少なくとも硫酸カルシウム及び不純物を含み、この第１の液相はリン酸及び溶解したリン酸一カルシウムを含み、この攻撃は、硫酸から及び場合により硫酸塩源からの硫酸塩とカルシウムとのモル比が０．６～０．８の間に含まれ、攻撃タンクのＰ_２Ｏ_５含有量は６％未満である投入条件で行われる、攻撃工程と、
－この第１の液相からのこの第１の固形物の分離を伴うこの第１のスラリーの第１の濾過工程と、
－精製されたリン酸塩系化合物のこの第１の液相からの回収工程と
を含む。
Advantageously, the process according to the invention comprises
- with sulfuric acid of the phosphate source one, two or for a predetermined period of time ranging from 20 to 180 minutes with the formation of a first suspension comprising a first solid and a first liquid phase Acid attack in a plurality of attack tanks, the first solids being in suspension, the first solids comprising at least calcium sulfate and impurities, the first liquid phase comprising phosphoric acid and dissolved The attack comprises monocalcium phosphate from sulfuric acid and optionally a sulfate to calcium molar ratio between 0.6 and 0.8 and the P ₂ O in the attack tank. ₅ content is less than 6%, the attack step is carried out at input conditions,
- a first filtration step of said first slurry with separation of said first solids from said first liquid phase;
- recovering the purified phosphate-based compound from this first liquid phase.

本発明の１つの特定の実施形態では、本発明によるプロセスは、
－第１の固形物及び第１の液相を含む第１の懸濁液の形成を伴う、２０～１８０分の範囲の所定の期間における、このリン酸塩源の硫酸による攻撃タンクでの酸攻撃であって、第１の固形物は懸濁液中にあり、第１の固形物は少なくとも硫酸カルシウム及び不純物を含み、この第１の液相はリン酸及び溶解したリン酸一カルシウムを含み、この攻撃は硫酸から及び場合によりリン酸塩源からの硫酸塩とリン酸塩源中に存在するカルシウムとのモル比は０．６～０．８の間に含まれ、攻撃タンクのＰ_２Ｏ_５含有量は６％未満である、攻撃工程と、
－この第１の液相からのこの第１の固形物の分離を伴うこの第１のスラリーの第１の濾過工程と、
－精製されたリン酸塩系の化合物のこの第１の液相からの回収工程と
を含む。
In one particular embodiment of the invention, the process according to the invention comprises
- Acidification of this phosphate source in an attack tank with sulfuric acid for a predetermined period of time ranging from 20 to 180 minutes with the formation of a first suspension comprising a first solid and a first liquid phase. a first solid in suspension, the first solid comprising at least calcium sulfate and impurities, the first liquid phase comprising phosphoric acid and dissolved monocalcium phosphate; , this attack is comprised from sulfuric acid and optionally from the phosphate source with a molar ratio of sulphate to calcium present in the phosphate source between 0.6 and 0.8, the P ₂ of the attack tank an attack step, wherein the _O5 content is less than 6%;
- a first filtration step of said first slurry with separation of said first solids from said first liquid phase;
- recovering the purified phosphate-based compound from this first liquid phase.

Claims

1. A process of acid attack of a calcium-containing phosphate source for the production of a phosphate-based purified compound, comprising:
a) for a predetermined period of time ranging from 20 to 180 minutes with formation of a first suspension comprising a first solid and a first liquid phase in which said first solid is suspended an acid attack step using sulfuric acid of said phosphate source, said first solid comprising at least calcium sulfate and impurities, said first liquid phase comprising phosphoric acid and dissolved monocalcium phosphate; Said attack is from said sulfuric acid and from said phosphate source with a molar ratio of said sulfate to calcium from said phosphate _source in the range of 0.6 to _0.8 ; an acid attack step, conducted at input conditions where the content is less than 6%;
b) a first filtration step of said first suspension first slurry with separation of said first solids from said first liquid phase;
c) recovering the purified phosphate-based compound from said first liquid phase.

2. The process of claim 1, wherein said acid attack occurs in one, two or more attack tanks.

3. The process of claim 1 or 2, wherein said predetermined period of time is less than 120 minutes.

4. Process according to claim 2 or 3, wherein the _P2O5 content in the liquid phase in _the one or more attack tanks is less than 5%.

A process according to any one of claims 2 to 4, wherein said attack is carried out at said one or more attack tank temperatures of 90°C or less.

A process according to any one of claims 2 to 5 , wherein the sulfuric acid is dilute sulfuric acid before being added to the attack tank(s).

7. The process _of claim 6, wherein said dilute sulfuric acid is characterized by a _H2SO4 concentration of 13 wt% or less.

The method of claims 1-7, wherein the molar ratio of sulfate from said sulfuric acid and from said phosphate source to said calcium present in said phosphate source is in the range of 0.68 to 0.78. A process according to any one of paragraphs.

The process of any one of claims 1-8, further comprising adding a base to said first suspension prior to filtration.

forming a second suspension comprising a second solid of suspension in a second liquid phase prior to said step in which said phosphate-based purification compound is recovered from said first liquid phase; and adding a base to said first liquid phase after filtration, with filtration of said second suspension to separate said second solids in suspension from said second liquid phase. wherein said second phosphate-based purification compound is recovered from said second liquid phase from said first liquid phase having a lower content of said second solids. 10. The process of any one of 1-9.

A process according to any one of claims 1 to 10, wherein said first solid separated from said first liquid phase is recycled by introducing it into said first suspension.

The phosphate source containing _the calcium is conventional phosphate rock, phosphate rock with low _P2O5 content, ash, sludge from waste water treatment plants, bone ash, pig manure, poultry manure, sludge from waste water treatment plants. and any feedstock characterized by a phosphate content _of _P2O5 with a phosphate content of less than 30% by weight relative to the total weight of the feedstock ;
Process according to any one of the preceding claims, wherein the conventional phosphate rock has a typical P ₂ O ₅ content of more than 25 wt%.

The process of any one of claims 1-12, wherein the purified phosphate-based compound is monocalcium phosphate MCP, dicalcium phosphate DCP, or phosphoric acid .

A process according to any one of claims 10 to 13, wherein said second liquid phase is recycled by introducing it into said one or more attack tanks.