阅读说明：本技术 一种促凝剂及其制备方法和用途 (Coagulant and preparation method and application thereof ) 是由 李帆 戚婷婷 冉秀云 肖文韬 陈红霞 贾严严 于 2018-07-27 设计创作，主要内容包括：一种促凝剂及其制备方法和用途。所述促凝剂包括磷石膏和助磨剂；所述助磨剂为糖。所述促凝剂通过将磷石膏和助磨剂混合,研磨制备得到。该促凝剂能够有效缩短石膏板的初凝时间、终凝时间,更加高效；并且采用工业副产物磷石膏作为原料,实现了固体废弃物的再利用,是磷石膏资源化利用的一条途径。(A coagulant and its preparation method and application are provided. The coagulant comprises phosphogypsum and a grinding aid; the grinding aid is sugar. The coagulant is prepared by mixing phosphogypsum and a grinding aid and grinding. The coagulant can effectively shorten the initial setting time and the final setting time of the gypsum board, and is more efficient; and the industrial by-product phosphogypsum is used as a raw material, so that the reutilization of solid waste is realized, and the method is an approach for the resource utilization of the phosphogypsum.)

1. A set accelerator comprising phosphogypsum and a grinding aid.

2. The setting accelerator according to claim 1, wherein the grade of phosphogypsum is greater than 80%;

optionally, the moisture content of the phosphogypsum is below 0.5%.

3. The setting accelerator of claim 1, wherein the grinding aid is a sugar;

optionally, the sugar is an industrial sugar;

optionally, the water content of the grinding aid is less than 0.5%.

4. The setting accelerator according to any of claims 1 to 3, wherein the weight ratio of grinding aid to phosphogypsum is from 1 to 10: 100.

5. The setting accelerator according to any of claims 1 to 3, wherein the setting accelerator has an average particle size of not more than 20 μm.

6. A process for preparing an accelerator according to any one of claims 1 to 5, which comprises the steps of: mixing the phosphogypsum and the grinding aid, and grinding to obtain the coagulant.

7. The method of claim 6, further comprising: drying the phosphogypsum and the grinding aid until the water content is lower than 0.5 percent before mixing the phosphogypsum and the grinding aid.

8. The method of claim 6 or 7, wherein the grinding comprises grinding a coagulant to an average particle size of no greater than 20 μ ι η;

optionally, the grinding time is 20 min-40 min;

optionally, the rotation speed of the grinding is 300-500 r/min;

optionally, the temperature of the milling is below 45 ℃.

9. Use of the setting accelerator according to any of claims 1 to 5 or the setting accelerator prepared according to the process of any of claims 6 to 8 for the preparation of paper-faced gypsum board.

10. The use according to claim 9, wherein the coagulant is added in an amount of 0.1 to 2 parts by weight based on 100 parts by weight of the added gypsum clinker in the raw material for producing the paper-faced gypsum board.

11. The use of claim 10, wherein the raw materials for preparing the paper-surface gypsum board further comprise water, a binder, a water reducing agent and a foaming agent, based on 100 parts by weight of the added gypsum clinker, the added amount of the water is 55-85 parts by weight, the added amount of the binder is 0.4-1 part by weight, the added amount of the water reducing agent is 0.05-0.5 part by weight, and the added amount of the foaming agent is 0.1-1 part by weight.

12. The use according to claim 11, wherein,

the binder is selected from any one or more of native starch, modified corn starch and modified tapioca starch;

optionally, the water reducing agent is selected from any one or more of polycarboxylic acid water reducing agents and naphthalene water reducing agents;

optionally, the foaming agent is selected from any one or more of surfactant foaming agents, and is further optionally selected from any one or more of sodium lauryl sulfate and fatty acid foaming agents.

Technical Field

The present application relates to, but is not limited to, the field of building materials, and in particular, but not limited to, a method for the preparation of an accelerator and its use.

Background

The paper-surface gypsum board is one of the most widely used green building materials in China. The production and consumption of gypsum boards during the 'twelve five' period show an increasing trend, more than 20% of each year is achieved, and the production of gypsum boards in China exceeds 35 hundred million square meters in 2015.

Setting accelerators are required to be added to complete the setting during the gypsum board production process. The coagulant used in the prior art is gypsum powder, the particle size of the gypsum powder is large, generally 0.01-0.02 mm, the specific surface area is small, and the particle size is only 6000-7000 cm²And about/g. Therefore, in the production of gypsum plasterboards, the amount of accelerator added must be increased in order to exert its normal accelerating effect.

The production rate of modern gypsum board factories is as high as 180m/min, and in order to meet the production requirements, more efficient and stable coagulants are required.

The phosphogypsum is an industrial byproduct in the process of preparing phosphoric acid by a wet method, about 5 tons of phosphogypsum are generated when 1 ton of phosphoric acid is produced, and the accumulated storage amount of the phosphogypsum in China currently exceeds 3 hundred million tons. Particularly, as the year is 2018, the country collects 25 yuan/ton of solid waste environment protection tax to pollution discharge enterprises, so that the utilization of the phosphogypsum, a regenerated gypsum resource, is not slow.

Disclosure of Invention

The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

Gypsum is currently the most widely used coagulant. However, the initial setting time and final setting time of the gypsum board slurry are still long, and in order to solve the problems, the application aims to provide a high-efficiency gypsum board accelerator. On the basis of careful research on the prior art, the inventor of the application finds that the phosphogypsum is adopted to prepare the coagulant, so that the initial setting time and the final setting time of a gypsum board can be effectively shortened, the efficiency is higher, and the recycling of the phosphogypsum can be effectively realized.

The present application provides a set accelerator comprising phosphogypsum and a grinding aid.

The phosphogypsum generally contains impurities such as silicon and the like, the silicon hardness is high, and the phosphogypsum can play a part of the role of a grinding aid and improve the coagulation accelerating effect during preparation. Other impurity components in the phosphogypsum have low content and no adverse effect on the paper-surface gypsum board product. The phosphogypsum is used as the coagulant raw material, pretreatment such as impurity removal is not needed, and the process is simple and the effect is obvious while industrial byproducts are effectively utilized.

In some embodiments, the grade of the gypsum may be greater than 80%; the water content of the phosphogypsum can be lower than 0.5 percent.

The water content of the raw materials is controlled, the phenomenon of ball sticking is avoided, and the input-output ratio is improved.

In some embodiments, the grinding aid can be a sugar; the sugar can be industrial sugar; the water content of the grinding aid can be lower than 0.5 percent.

Because the hardness of the sugar is higher, the sugar is adopted as the grinding aid, so that the addition amount of the grinding aid can be reduced, and the production cost is reduced.

In some embodiments the weight ratio of grinding aid to phosphogypsum can be 1-10: 100.

In some embodiments, the coagulant average particle size may be no greater than 20 μm.

The smaller the particle size of the setting accelerator, the better the setting accelerator effect, and in the present application, the setting accelerator having an average particle size of not more than 20 μm can obtain a good setting accelerator effect.

The present application also provides a process for preparing an accelerator, comprising the steps of: mixing the phosphogypsum and the grinding aid, and grinding to obtain the coagulant.

In some embodiments, the method further comprises: before mixing the phosphogypsum and the grinding aid, drying the phosphogypsum and the grinding aid until the water content is lower than 0.5 percent.

In some embodiments, the grade of phosphogypsum may be greater than 80%.

In some embodiments, the grinding aid can be a sugar; the sugar may be an industrial sugar.

In some embodiments the weight ratio of grinding aid to phosphogypsum can be 1-10: 100.

In some embodiments, the average particle size of the coagulant resulting from milling may be no greater than 20 μm; the grinding time can be 20 min-40 min; the rotation speed of the grinding can be 300-500 r/min; the temperature of milling may be below 45 ℃.

At high temperatures, the grinding aid may melt and agglomerate, resulting in deterioration of accelerator performance, and therefore the temperature of grinding can be controlled below 45 ℃.

The application also provides the application of the coagulant or the coagulant prepared by the preparation method in the preparation of the gypsum plasterboard.

In some embodiments, the coagulant may be added in an amount of 0.1 to 2 parts by weight based on 100 parts by weight of the gypsum clinker in the raw material for producing the paper-faced gypsum board.

In some embodiments, the raw materials for preparing the paper-surface gypsum board may further include water, a binder, a water reducing agent and a foaming agent, wherein the water may be added in an amount of 55 to 85 parts by weight, the binder may be added in an amount of 0.4 to 1 part by weight, the water reducing agent may be added in an amount of 0.05 to 0.5 part by weight, and the foaming agent may be added in an amount of 0.1 to 1 part by weight, based on 100 parts by weight of the gypsum clinker.

In some embodiments, the binder may be selected from any one or more of native starch, modified corn starch, and modified tapioca starch; the water reducing agent can be selected from any one or more of polycarboxylic acid water reducing agents and naphthalene water reducing agents; the foaming agent may be selected from any one or more of surfactant based foaming agents, for example may be selected from any one or more of sodium lauryl sulfate and fatty acid based foaming agents.

Compared with the prior art, the application has the beneficial effects that:

1. according to the coagulant, grinding aid sugar is added for grinding, so that the initial setting time and final setting time of the gypsum board can be effectively shortened, and the efficiency is higher;

2. the coagulant of the application adopts the industrial by-product phosphogypsum as a raw material, realizes the reutilization of solid waste, and is a way for the resource utilization of the phosphogypsum;

3. the application of the coagulant facilitates the preparation process of the paper-surface gypsum board.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. The objectives and other advantages of the application may be realized and attained by the structure particularly pointed out in the written description and claims hereof.

Detailed Description

Hereinafter, embodiments of the present application will be described in detail to make objects, technical solutions and advantages of the present application more apparent. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.