阅读说明：本技术 一种含磷废料制备钙镁磷肥的方法 (Method for preparing calcium magnesium phosphate fertilizer from phosphorus-containing waste ) 是由 宋金容 宋芷昕 于 2019-10-30 设计创作，主要内容包括：本发明提供一种含磷废料制备钙镁磷肥的方法。该制备方法包括以下步骤：利用含磷废液、废渣与含钙、镁碱性物料进行混合；经旋窑、立窑高温煅烧冷却；粉碎混合烘干制备成为钙镁磷肥。该制备工艺简单,环保,解决了废铝刻液、抛光液的回收再利用问题,产品稳定,制备出的钙镁磷肥符合国家行业标准,具有较高的经济效益和社会意义。(The invention provides a method for preparing a calcium magnesium phosphate fertilizer from phosphorus-containing waste. The preparation method comprises the following steps: mixing phosphorus-containing waste liquid and waste residue with calcium-containing and magnesium-containing alkaline materials; calcining at high temperature in a rotary kiln and a vertical kiln, and cooling; pulverizing, mixing and drying to obtain the calcium magnesium phosphate fertilizer. The preparation process is simple and environment-friendly, solves the problem of recycling waste aluminum etching solution and polishing solution, has stable product, and the prepared calcium magnesium phosphate fertilizer meets the national industrial standard and has higher economic benefit and social significance.)

1. A calcium magnesium phosphate fertilizer is characterized by comprising the following raw materials: 30-80% of calcium and magnesium containing alkaline material, 0-30% of fuel and 20-70% of phosphorus containing material.

2. The calcium-magnesia phosphate fertilizer as claimed in claim 1, wherein the molar ratio of calcium to magnesium in the calcium-and magnesium-containing alkaline material is 0.5-3: 1, and specifically is one, two or more of limestone, dolomite, brucite, magnesite and serpentine; preferably, the fuel is one or two of coke and fly ash.

3. The calcium-magnesia phosphate fertilizer as claimed in claim 1, characterized in that the basic material containing calcium and magnesium is two or more of magnesium oxide, magnesium hydroxide, calcium oxide, calcium hydroxide, calcium carbonate and magnesium carbonate, and the molar ratio of calcium to magnesium is 0.5-3: 1.

4. The calcium magnesium phosphate fertilizer as claimed in claim 1, wherein the phosphorus-containing material is one of a phosphorus-containing waste liquid and a phosphorus-containing waste residue, wherein the phosphorus-containing waste liquid contains 20-75% of phosphoric acid, and the phosphorus-containing waste residue comprises the following components in percentage by weight: 10-40% of phosphorus pentoxide, 20-50% of calcium oxide, 0.5-20% of magnesium oxide, 2-20% of silicon oxide and the balance of water.

5. The calcium-magnesia phosphate fertilizer according to claim 1, wherein the phosphorus-containing waste liquid is an aluminum etching waste liquid generated in a process of manufacturing liquid crystal displays and a triacid polishing waste liquid used for chemical polishing of aluminum and aluminum alloys; the phosphorus-containing waste residue is phosphorus residue obtained by neutralizing reaction of phosphorus-containing waste liquid of an electronic plant and lime and filtering.

6. The process for the preparation of a calcium-magnesia phosphate fertilizer according to any one of claims 1 to 5, characterized by the following steps:

s1, adding 30-80% of basic materials containing calcium and magnesium and 5-30% of fuel, crushing until the particle size is 10-150 mm, and spraying 20-70% of phosphorus-containing waste liquid or adding 20-70% of phosphorus-containing waste residues;

s2, feeding the materials into a rotary kiln/blast furnace, introducing hot air, reacting at 400-1800 ℃ for 0.2-24 h, fully melting, overheating and discharging;

and S3, cooling, ball-milling, collecting a product, and packaging.

7. The method for preparing a calcium-magnesia phosphate fertilizer as claimed in claim 6, characterized in that the calcium-containing and magnesium-based material in S1 is one, two or more of limestone, dolomite, brucite, magnesite and serpentine; preferably, the particle size of the crushed calcium-containing and magnesium-containing alkaline material and the fuel in the S1 is 10-80 mm; preferably, the reaction temperature in the S2 is 600-1400 ℃.

8. The method for preparing a calcium-magnesia phosphate fertilizer according to claim 6, wherein the cooling in S3 is water spray cooling, air cooling or natural cooling, wherein the water spray cooling is followed by feeding into a rotary drying furnace for drying; the product collected in S3 includes the powder material milled by the ball mill and the dust collected by the cyclone and bag filter.

9. The process for the preparation of a calcium-magnesia phosphate fertilizer according to any one of claims 1 to 5, characterized by the following steps:

s1, adding 30-80% of alkaline materials containing calcium and magnesium, and adding 20-70% of phosphorus-containing waste liquid or phosphorus-containing waste residue;

s2, mixing the materials by a double-shaft mixer for 0.2-10 minutes, uniformly mixing, and then sending the mixture into a rotary drying furnace to react for 30-60 minutes, wherein the temperature of a furnace head is 600-800 ℃, and the temperature of a furnace tail is 40-80 ℃;

and S3, cooling, ball-milling, collecting a product, and packaging.

10. The method for preparing a calcium-magnesia phosphate fertilizer according to claim 9, characterized in that the basic materials containing calcium and magnesium in S1 are two or more of magnesium oxide, magnesium hydroxide, calcium oxide, calcium hydroxide, calcium carbonate and magnesium carbonate, and the molar ratio of calcium to magnesium is 0.5-3: 1.

Technical Field

The invention relates to the technical field of industrial waste liquid treatment, in particular to a method for preparing a calcium magnesium phosphate fertilizer from phosphorus-containing waste.

Background

In recent years, the semiconductor industry has been rapidly developed, the materials of aluminum and aluminum alloy are widely used, and a large amount of phosphorus-containing wastes are generated in the manufacturing process, such as aluminum etching waste liquid generated in the manufacturing process of liquid crystal displays and the like, and triacid polishing waste liquid used for chemical polishing of aluminum and aluminum alloy. At present, the research on recycling of waste aluminum etching solution and polishing solution is less, and the waste aluminum etching solution and the polishing solution are treated by adopting an incineration method, so that the resource is wasted and the environment is polluted. Phosphorite is a material basis for manufacturing phosphate fertilizers and fine chemical products, is an important strategic resource, and tends to be poor due to the non-regenerability of the phosphorite. Therefore, the recycling of the phosphorus-containing waste liquid is very important.

The preparation of the phosphorus compound fertilizer by using the waste etching liquid and the low-grade phosphorite as raw materials comprises the steps of decomposing the low-grade phosphorite by using the aluminum etching waste liquid to prepare the phosphorus compound fertilizer, recycling the waste liquid and the low-grade phosphorite, and generating waste residues. CN 200810241481.X comprehensive utilization method of chemical polishing waste phosphoric acid reports that calcium hydrophosphate is prepared by neutralizing waste phosphoric acid with lime milk, but has the defect of generating a small amount of sludge. The 'CN 201710393298.0 chemical polishing waste phosphoric acid treatment method and fertilizer preparation method' reports that potassium dihydrogen phosphate is obtained by repeatedly distilling and filtering by using a neutralizing agent and a precipitating agent, and the method has a complex process and cannot fully utilize waste liquid.

The existing distillation or extraction method can only treat the aluminum etching waste liquid with less impurities and the sulfuric acid-containing triacid polishing waste liquid, the treatment is not thorough, the complete separation cannot be realized, the process is complex, the cost is high, and the solid phosphorus-containing waste residue cannot be treated. The method for preparing the phosphorus compound fertilizer is adopted to treat the phosphorus-containing waste liquid, waste residues are generated, the waste liquid is not completely utilized, and the solid phosphorus-containing waste residues cannot be treated.

Disclosure of Invention

The first purpose of the invention is to provide a calcium magnesium phosphate fertilizer prepared by using phosphorus-containing waste liquid and slag.

The second purpose of the invention is to provide a preparation method of the calcium magnesium phosphate fertilizer.

In order to realize the first purpose, the invention provides a calcium magnesium phosphate fertilizer. The raw materials comprise: 30-80% of calcium and magnesium containing alkaline materials, 0-30% of fuel and 20-70% of phosphorus containing waste liquid and slag.

The molar ratio of calcium to magnesium in the calcium and magnesium containing alkaline material is 0.5-3: 1;

the calcium-containing and magnesium-containing alkaline material is one, two or more of limestone, dolomite, brucite, magnesite and serpentine;

preferably, the calcium-containing and magnesium-containing alkaline material is two or more of magnesium oxide, magnesium hydroxide, calcium oxide, calcium hydroxide, calcium carbonate and magnesium carbonate;

the fuel is one of coke and fly ash;

the fly ash contains silicon dioxide, and can be used as a fuel and a silicon source of a calcium magnesium phosphate fertilizer.

Preferably, the fuel accounts for 5-30%;

the phosphorus-containing material is one or two of phosphorus-containing waste liquid and phosphorus-containing waste residue;

the phosphorus-containing waste liquid is aluminum etching waste liquid generated in the manufacturing process of liquid crystal display and the like and triacid polishing waste liquid used for chemical polishing of aluminum and aluminum alloy;

the phosphorus-containing waste residue is phosphorus residue obtained by neutralizing reaction of phosphorus-containing waste liquid of an electronic plant and lime and filtering.

The content of phosphoric acid in the phosphorus-containing waste liquid is 20-75%;

the phosphorus-containing waste residue comprises the following components:

the content of phosphorus pentoxide is 10-40%,

the content of calcium oxide is 20-50%,

the content of magnesium oxide is 0.5-20%,

the content of silicon oxide is 0.5-20%,

the balance of water.

In order to achieve the second object, the invention provides a preparation method of a calcium magnesium phosphate fertilizer. The method comprises the following specific steps:

s1, adding 30-80% of basic materials containing calcium and magnesium and 5-30% of fuel, crushing until the particle size is 10-150 mm, and spraying 20-70% of phosphorus-containing waste liquid or adding 20-70% of phosphorus-containing waste residues;

s2, feeding the materials into a rotary kiln/blast furnace, introducing hot air, reacting at 400-1800 ℃ for 0.2-24 h, fully melting, overheating and discharging;

and S3, cooling, ball-milling, collecting a product, and packaging.

The calcium-containing and magnesium-containing alkaline material in the S1 is one, two or more of limestone, dolomite, brucite, magnesite and serpentine;

the cooling in the S3 is water spray cooling, air cooling or natural cooling, wherein the water spray cooling is carried out and then the water spray cooling is sent into a rotary drying furnace for drying;

the product collected in S3 includes the powder material milled by the ball mill and the dust collected by the cyclone and bag filter.

Preferably, the particle size of the crushed S1 is 10-80 mm;

preferably, the temperature in the furnace in S2 is kept between 600 and 1400 ℃.

In another aspect, the invention provides another method for preparing a calcium magnesium phosphate fertilizer. The method comprises the following specific steps:

s1, adding 30-80% of alkaline materials containing calcium and magnesium, and adding 20-70% of phosphorus-containing waste liquid or phosphorus-containing waste residue;

s2, mixing the materials by a double-shaft mixer for 0.2-10 minutes, uniformly mixing, and then sending the mixture into a rotary drying furnace to react for 30-100 minutes, wherein the temperature of a furnace head is 400-800 ℃, and the temperature of a furnace tail is 40-80 ℃;

and S3, cooling, ball-milling, collecting a product, and packaging.

The basic material containing calcium and magnesium in the S1 is one, two or more of magnesium oxide, magnesium hydroxide, calcium oxide, calcium hydroxide, calcium carbonate and magnesium carbonate.

The cooling in the S3 is water spray cooling, air cooling or natural cooling, wherein the water spray cooling is then sent into a rotary drying furnace for drying;

the product collected in S3 includes the powder material milled by the ball mill and the dust collected by the cyclone and bag filter.

The reaction equation in the preparation process is as follows:

2H₃PO₄+3CaCO₃→Ca₃(PO₄)₂+3CO₂↑+3H₂O↑

2H₃PO₄+3MgCO₃→Mg₃(PO₄)₂+3CO₂↑+3H₂O↑

CaO+MgO+2SiO₂→MgSiO₃+CaSiO₃

Ca(H₂PO₄)₂+2CaO→Ca₃(PO₄)₂+2H₂O↑

2H₃PO₄+3CaO→Ca₃(PO₄)₂+3H₂O↑

2H₃PO₄+3MgO→Mg₃(PO₄)₂+3H₂O↑

the invention has the beneficial effects that:

the invention provides a preparation method of a calcium magnesium phosphate fertilizer. Compared with the existing treatment of phosphorus-containing waste liquid and waste residue, the method has the advantages of wide treatment range, high reaction speed, utilization rate of 100 percent, simple process, environmental protection and strong operability.

In the first method, the phosphorus-containing waste liquid and the waste residues can be subjected to neutralization reaction by using ore raw materials such as limestone and the like, so that the cost is low; in the second method, the reaction is carried out by utilizing the calcium oxide and magnesium oxide reagents of the finished product, and the reaction rate is higher.

Detailed Description

In order to more clearly and completely describe the technical scheme of the invention, the invention is further described in detail by the specific embodiments, and it should be understood that the specific embodiments described herein are only used for explaining the invention, and are not used for limiting the invention, and various changes can be made within the scope defined by the claims of the invention.