阅读说明：本技术 一种磷石膏用改进剂的制备方法 (Preparation method of improver for phosphogypsum ) 是由 沈焱 钱佳佳 时磊 郑媛媛 于 2021-08-26 设计创作，主要内容包括：本发明公开了一种磷石膏用改进剂的制备方法,包括步骤为：对天然石膏进行球磨,将磨细的天然石膏进行浸泡得到天然石膏混合水溶液；采用水热法煅烧所述天然石膏混合水溶液,得到改性组分；将所述改性组分与硬脂酸钙、磷酸三丁酯、气相二氧化硅混合,得到磷石膏用改进剂。通过上述方式,本发明将磷石膏掺入改性剂后可以提高磷石膏的软化系数,使软化系数大于0.98,有效提高了磷石膏的性能,能够实现磷石膏更广泛的应用。(The invention discloses a preparation method of a modifier for phosphogypsum, which comprises the following steps: ball-milling natural gypsum, and soaking the ground natural gypsum to obtain a natural gypsum mixed aqueous solution; calcining the natural gypsum mixed aqueous solution by a hydrothermal method to obtain a modified component; and mixing the modified component with calcium stearate, tributyl phosphate and fumed silica to obtain the improver for the phosphogypsum. By adopting the mode, the softening coefficient of the phosphogypsum can be improved after the phosphogypsum is doped with the modifier, the softening coefficient is larger than 0.98, the performance of the phosphogypsum is effectively improved, and the phosphogypsum can be widely applied.)

1. The preparation method of the improver for the phosphogypsum is characterized by comprising the following steps: (1) ball-milling natural gypsum, and soaking the ground natural gypsum to obtain a natural gypsum mixed aqueous solution; (2) calcining the natural gypsum mixed aqueous solution by a hydrothermal method to obtain a modified component; (3) and mixing the modified component with calcium stearate, tributyl phosphate and fumed silica to obtain the improver for the phosphogypsum.

2. The preparation method of the improver for phosphogypsum, as claimed in claim 1, is characterized in that, the ball milling in the step (1) is carried out by a ball mill.

3. The preparation method of the improver for phosphogypsum as claimed in claim 1, wherein the ball milling in the step (1) is to ball mill the specific surface area of the natural gypsum to 6000-6500 m²/kg。

4. The preparation method of the improver for phosphogypsum as claimed in claim 1, wherein the natural gypsum after ball milling in the step (1) is sieved by a 400-mesh sieve, and the balance is not more than 0.5%.

5. The method for preparing the improver for phosphogypsum according to claim 1, wherein the soaking in the step (1) is soaking in succinic acid.

6. The preparation method of the improver for phosphogypsum, as claimed in claim 5, wherein the succinic acid in step (1) is 4-7% by mass.

7. The method for preparing the improver for phosphogypsum as claimed in claim 1, wherein the soaking time in step (1) is 23-28 hours.

8. The preparation method of the improver for phosphogypsum as claimed in claim 1, wherein the calcination in step (2) is carried out at a temperature of 550-700 ℃, a pressure of 0.4-0.6MPa and a time of 5-7 hours.

9. The preparation method of the improver for phosphogypsum, as claimed in claim 1, wherein in step (3), the contents of the modifying component, the calcium stearate, the tributyl phosphate and the fumed silica are, by parts, 65-75 parts of the modifying component, 6-10 parts of the calcium stearate, 10-15 parts of the tributyl phosphate and 8-13 parts of the fumed silica.

10. The preparation method of the improver for the phosphogypsum as claimed in claim 1, wherein the improver for the phosphogypsum is added in an amount of 0.5-1.5% of the mass of the phosphogypsum.

Technical Field

The invention relates to the technical field of building materials, in particular to a preparation method of a modifier for phosphogypsum.

Background

Phosphogypsum refers to solid waste residue generated when phosphorite is treated by sulfuric acid in phosphoric acid production, and the main component of the phosphogypsum is calcium sulfate. The main component of the phosphogypsum is CaSO₄·2H₂O, and in addition, various other impurities. The phosphogypsum is generally powdery, generally has the colors of grey white, grey yellow, light green and the like, and also contains organic phosphorus and sulfur fluorine compounds. The building phosphogypsum and the product which are prepared by dehydrating the phosphogypsum and take the beta-hemihydrate gypsum as the main component are effective ways for recycling the phosphogypsum and the product, and simultaneously can achieve the aim of eliminatingConsuming a large amount of phosphogypsum waste residue. The existing phosphogypsum has low softening coefficient, poor performance and poor application effect.

Disclosure of Invention

The invention mainly solves the technical problem of providing a preparation method of the improver for the phosphogypsum, which can improve the softening coefficient of the phosphogypsum.

In order to solve the technical problems, the invention adopts a technical scheme that: the preparation method of the improver for the phosphogypsum comprises the following steps: (1) ball-milling natural gypsum, and soaking the ground natural gypsum to obtain a natural gypsum mixed aqueous solution; (2) calcining the natural gypsum mixed aqueous solution by a hydrothermal method to obtain a modified component; (3) and mixing the modified component with calcium stearate, tributyl phosphate and fumed silica to obtain the improver for the phosphogypsum.

In a preferred embodiment of the present invention, the ball milling in step (1) is performed by using a ball mill.

In a preferred embodiment of the present invention, the ball milling in step (1) is to ball mill the specific surface area of the natural gypsum to 6000 to 6500m²/kg。

In a preferred embodiment of the invention, the natural gypsum after ball milling in the step (1) is sieved by a 400-mesh sieve, and the balance is not more than 0.5%.

In a preferred embodiment of the present invention, the soaking in step (1) is soaking in succinic acid.

In a preferred embodiment of the present invention, the succinic acid in the step (1) is 4 to 7% by mass of succinic acid.

In a preferred embodiment of the present invention, the soaking time in step (1) is 23 to 28 hours.

In a preferred embodiment of the present invention, the temperature of the calcination in step (2) is 550-700 ℃, the pressure is 0.4-0.6MPa, and the time is 5-7 hours.

In a preferred embodiment of the present invention, in the step (3), the contents of the modifying component, the calcium stearate, the tributyl phosphate and the fumed silica are, by parts, 65-75 parts of the modifying component, 6-10 parts of the calcium stearate, 10-15 parts of the tributyl phosphate and 8-13 parts of the fumed silica.

In a preferred embodiment of the invention, the addition amount of the improver for the phosphogypsum is 0.5-1.5% of the mass of the phosphogypsum.

The invention has the beneficial effects that: according to the preparation method of the improver for the phosphogypsum, the softening coefficient of the phosphogypsum can be improved after the modifier is doped into the phosphogypsum, so that the softening coefficient is larger than 0.98, the performance of the phosphogypsum is effectively improved, and the phosphogypsum can be widely applied.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The first embodiment is as follows:

the preparation method of the improver for the phosphogypsum comprises the following steps:

(1) ball milling natural gypsum by a ball mill to make the specific surface area of the natural gypsum ball-milled to 6300m²Kg, the balance of the 400-mesh sieve is not more than 0.5 percent;

(2) fully soaking the ground natural gypsum in succinic acid with the mass fraction of 5% for 24 hours to obtain a natural gypsum mixed aqueous solution;

(3) calcining the natural gypsum mixed aqueous solution by a hydrothermal method at the calcining temperature of 600 ℃, the calcining pressure of 0.5MPa and the calcining time of 6 hours to obtain a modified component, wherein the modified component is in a powder shape;

(4) fully mixing 700kg of modified components with 80kg of calcium stearate, 120kg of tributyl phosphate and 100kg of fumed silica to obtain a modifier for phosphogypsum;

(5) the mixing amount of the improver for the phosphogypsum is 1 percent of the mass of the phosphogypsum, and after the improver for the phosphogypsum is mixed, the softening coefficient of the phosphogypsum is 0.99.

Example two:

the preparation method of the improver for the phosphogypsum comprises the following steps:

(1) ball milling natural gypsum by a ball mill to ensure that the specific surface area of the natural gypsum is 6000m²Kg, the balance of the 400-mesh sieve is not more than 0.5 percent;

(2) fully soaking the ground natural gypsum in succinic acid with the mass fraction of 7% for 23 hours to obtain a natural gypsum mixed aqueous solution;

(3) calcining the natural gypsum mixed aqueous solution by a hydrothermal method at the temperature of 550 ℃, under the pressure of 0.6MPa for 7 hours to obtain a modified component, wherein the modified component is in a powder shape;

(4) fully mixing 650kg of modified components with 100kg of calcium stearate, 100kg of tributyl phosphate and 130kg of fumed silica to obtain a modifier for phosphogypsum;

(5) the addition amount of the improver for the phosphogypsum is 1.5 percent of the mass of the phosphogypsum, and after the improver is added, the softening coefficient of the phosphogypsum is 0.993.

Example three:

the preparation method of the improver for the phosphogypsum comprises the following steps:

(1) ball milling natural gypsum by a ball mill to make the specific surface area of the natural gypsum ball-milled to 6500m²Kg, the balance of the 400-mesh sieve is not more than 0.5 percent;

(2) fully soaking the ground natural gypsum in succinic acid with the mass fraction of 4% for 28 hours to obtain a natural gypsum mixed aqueous solution;

(3) calcining the natural gypsum mixed aqueous solution by a hydrothermal method at 700 ℃, 0.4MPa and 5 hours to obtain a modified component, wherein the modified component is powdery;

(4) fully mixing 750kg of modified components with 60kg of calcium stearate, 150kg of tributyl phosphate and 80kg of fumed silica to obtain a modifier for phosphogypsum;

(5) the mixing amount of the improver for the phosphogypsum is 0.5 percent of the mass of the phosphogypsum, and after the improver for the phosphogypsum is mixed, the softening coefficient of the phosphogypsum is 0.989.

The invention has the beneficial effects that:

the modifier is prepared by the preparation method of the improver for the phosphogypsum, and the softening coefficient of the phosphogypsum can be improved by doping the phosphogypsum into the modifier, so that the softening coefficient is larger than 0.98;

secondly, the modifier is prepared by the preparation method of the improver for the phosphogypsum, and the modifier effectively improves the performance of the phosphogypsum and can realize wider application of the phosphogypsum.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.