Method and device for producing nano calcium carbonate by microwave drying

Abstract

The invention discloses a method for producing nano calcium carbonate by microwave drying. The method is carried out according to the following steps: (1) preparing Ca(OH)2 raw refined slurry; (2) preparing boiled calcium carbonate slurry; (3) preparing an activated calcium carbonate filter cake; (4) pelletizing; (5) carrying out microwave drying; and (6) crushing and sieving to prepare a nano calcium carbonate product. A device for producing nano calcium carbonate by microwave drying comprises a pelletizer, a feeding hopper, a conveyor belt, a transmission mechanism, a tunnel type microwave drying box, a microwave generator, a discharge hopper and a moisture removal mechanism. The method and the device are adopted to produce nano calcium carbonate, so that time of drying operation in a production process of the nano calcium carbonate can be greatly shortened, the energy consumption is lowered, the agglomeration of the nano calcium carbonate is weakened and the dispersion is improved, and thus, the quality of the nano calcium carbonate is improved; the prepared nano calcium carbonate has the advantages of small grain size, low agglomeration strength, a great specific surface area, small hardness and good dispersion; and moreover, the heating time is short, so that the whiteness of the nano calcium carbonate can be improved.

Description

technical field

[0001] The invention relates to the technical field of nano-calcium carbonate production, in particular to a method and device for producing nano-calcium carbonate by microwave drying. Background technique

[0002] Nano-calcium carbonate is a new type of ultra-fine solid powder material developed in the 1980s, with a particle size between 0.01 and 0.1 μm. Due to the superfineness of nano-calcium carbonate particles, its crystal structure and surface electronic structure change, resulting in quantum size effects, small size effects, surface effects and macroscopic quantum effects that ordinary calcium carbonate does not have. It can be widely used in plastics, Rubber, paint, ink, sealing adhesive materials, coatings and other fields.

[0003] Due to the strong hydrophilic groups on the surface of nano-calcium carbonate, the affinity between nano-calcium carbonate and polymers is poor, and nano-calcium carbonate has extremely high free energy and polarity. Ha...

Examples

Embodiment 1

[0025] A method utilizing microwave drying to produce nano-calcium carbonate is implemented according to the following steps:

[0026] ①Preparation of Ca(OH) 2 Raw seminal pulp: calcined with limestone to obtain calcium oxide, which is digested with water to obtain Ca(OH) 2 Raw pulp, then aged, sieved to remove impurities, and prepared Ca(OH) 2 seminal plasma;

[0027] ②Calcium carbonate cooked pulp: adjust Ca(OH) 2 The temperature and mass percent concentration of raw seminal plasma, temperature is controlled at 20 ℃, and mass percent concentration is controlled at 10%, then Ca(OH) 2 Raw seminal pulp is added to the bubbling carbonization tower reactor and CO 2The gas is carbonized by bubbling and carbonized, and the carbonization is stopped when the pH of the slurry is less than or equal to 7.5, and the calcium carbonate cooked slurry is obtained;

[0028] ③Preparation of active calcium carbonate filter cake: add surface treatment agent to the calcium carbonate cooked p...

Embodiment 2

[0033] A method utilizing microwave drying to produce nano-calcium carbonate is implemented according to the following steps:

[0034] ①Preparation of Ca(OH) 2 Raw seminal pulp: calcined with limestone to obtain calcium oxide, which is digested with water to obtain Ca(OH) 2 Raw pulp, then aged and sieved to remove impurities to obtain Ca(OH) 2 seminal plasma;

[0035] ②Calcium carbonate cooked pulp: adjust Ca(OH) 2 The temperature and mass percent concentration of raw seminal pulp, temperature is controlled at 8 ℃, and mass percent concentration is controlled at 5%, then Ca(OH) 2 Raw seminal pulp is added to the bubbling carbonization tower reactor and CO 2 The gas is carbonized by bubbling and carbonized, and the carbonization is stopped when the pH of the slurry is less than or equal to 7.5, and the calcium carbonate cooked slurry is obtained;

[0036] ③Preparation of active calcium carbonate filter cake: add surface treatment agent to the calcium carbonate cooked pulp,...

Embodiment 3

[0041] A method utilizing microwave drying to produce nano-calcium carbonate is implemented according to the following steps:

[0042] ①Preparation of Ca(OH) 2 Raw seminal pulp: calcined with limestone to obtain calcium oxide, which is digested with water to obtain Ca(OH) 2 Raw pulp, then aged, sieved to remove impurities, and prepared Ca(OH) 2 seminal plasma;

[0043] ②Calcium carbonate cooked pulp: adjust Ca(OH) 2 The temperature and mass percent concentration of raw seminal pulp, temperature is controlled at 25 ℃, and mass percent concentration is controlled at 12%, then Ca(OH) 2 Raw seminal pulp is added to the bubbling carbonization tower reactor and CO 2 The gas is carbonized by bubbling and carbonized, and the carbonization is stopped when the pH of the slurry is less than or equal to 7.5, and the calcium carbonate cooked slurry is obtained;

[0044] ③Preparation of active calcium carbonate filter cake: add surface treatment agent to the calcium carbonate cooked pu...

technical field

[0001] The invention relates to the technical field of nano-calcium carbonate production, in particular to a method and device for producing nano-calcium carbonate by microwave drying. Background technique

[0002] Nano-calcium carbonate is a new type of ultra-fine solid powder material developed in the 1980s, with a particle size between 0.01 and 0.1 μm. Due to the superfineness of nano-calcium carbonate particles, its crystal structure and surface electronic structure change, resulting in quantum size effects, small size effects, surface effects and macroscopic quantum effects that ordinary calcium carbonate does not have. It can be widely used in plastics, Rubber, paint, ink, sealing adhesive materials, coatings and other fields.

[0003] Due to the strong hydrophilic groups on the surface of nano-calcium carbonate, the affinity between nano-calcium carbonate and polymers is poor, and nano-calcium carbonate has extremely high free energy and polarity. Ha...

Examples

Embodiment 1

[0025] A method utilizing microwave drying to produce nano-calcium carbonate is implemented according to the following steps:

[0026] ①Preparation of Ca(OH) 2 Raw seminal pulp: calcined with limestone to obtain calcium oxide, which is digested with water to obtain Ca(OH) 2 Raw pulp, then aged, sieved to remove impurities, and prepared Ca(OH) 2 seminal plasma;

[0027] ②Calcium carbonate cooked pulp: adjust Ca(OH) 2 The temperature and mass percent concentration of raw seminal plasma, temperature is controlled at 20 ℃, and mass percent concentration is controlled at 10%, then Ca(OH) 2 Raw seminal pulp is added to the bubbling carbonization tower reactor and CO 2The gas is carbonized by bubbling and carbonized, and the carbonization is stopped when the pH of the slurry is less than or equal to 7.5, and the calcium carbonate cooked slurry is obtained;

[0028] ③Preparation of active calcium carbonate filter cake: add surface treatment agent to the calcium carbonate cooked p...

Embodiment 2

[0033] A method utilizing microwave drying to produce nano-calcium carbonate is implemented according to the following steps:

[0034] ①Preparation of Ca(OH) 2 Raw seminal pulp: calcined with limestone to obtain calcium oxide, which is digested with water to obtain Ca(OH) 2 Raw pulp, then aged and sieved to remove impurities to obtain Ca(OH) 2 seminal plasma;

[0035] ②Calcium carbonate cooked pulp: adjust Ca(OH) 2 The temperature and mass percent concentration of raw seminal pulp, temperature is controlled at 8 ℃, and mass percent concentration is controlled at 5%, then Ca(OH) 2 Raw seminal pulp is added to the bubbling carbonization tower reactor and CO 2 The gas is carbonized by bubbling and carbonized, and the carbonization is stopped when the pH of the slurry is less than or equal to 7.5, and the calcium carbonate cooked slurry is obtained;

[0036] ③Preparation of active calcium carbonate filter cake: add surface treatment agent to the calcium carbonate cooked pulp,...

Embodiment 3

[0041] A method utilizing microwave drying to produce nano-calcium carbonate is implemented according to the following steps:

[0042] ①Preparation of Ca(OH) 2 Raw seminal pulp: calcined with limestone to obtain calcium oxide, which is digested with water to obtain Ca(OH) 2 Raw pulp, then aged, sieved to remove impurities, and prepared Ca(OH) 2 seminal plasma;

[0043] ②Calcium carbonate cooked pulp: adjust Ca(OH) 2 The temperature and mass percent concentration of raw seminal pulp, temperature is controlled at 25 ℃, and mass percent concentration is controlled at 12%, then Ca(OH) 2 Raw seminal pulp is added to the bubbling carbonization tower reactor and CO 2 The gas is carbonized by bubbling and carbonized, and the carbonization is stopped when the pH of the slurry is less than or equal to 7.5, and the calcium carbonate cooked slurry is obtained;

[0044] ③Preparation of active calcium carbonate filter cake: add surface treatment agent to the calcium carbonate cooked pu...

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