阅读说明：本技术 一种混凝土搅拌站废浆沉降剂及其制备方法和使用方法 (Waste slurry settling agent for concrete mixing plant and preparation method and use method thereof ) 是由 刘明 王军 张磊 高育欣 曾超 杨文� 王福涛 叶子 闫松龄 吴雄 于 2021-09-22 设计创作，主要内容包括：本发明公开了一种混凝土搅拌站废浆沉降剂及其制备方法和使用方法,属于混凝土搅拌站废浆沉降浓缩技术领域,该混凝土搅拌站废浆沉降剂包括以下质量份的原料：20～30份絮凝剂、10～20份密实剂和5～10份表面活性剂。本发明中的沉降剂加入到固含量为10％～35％废浆中沉降1～48h后可分离得到固含55％～60％的高固含废浆,简化了资源化利用固废过程,降低了企业的生产成本,具有良好的降本增效作用；可有效提升搅拌站废浆沉降效率,增加沉降后废浆固含,减小不同批次废浆沉降后固含差异,有助于废浆减量,实现搅拌站行业绿色生产。(The invention discloses a waste slurry settling agent for a concrete mixing plant and a preparation method and a using method thereof, belonging to the technical field of waste slurry settling and concentration of the concrete mixing plant, wherein the waste slurry settling agent for the concrete mixing plant comprises the following raw materials in parts by mass: 20-30 parts of flocculating agent, 10-20 parts of compacting agent and 5-10 parts of surfactant. The settling agent is added into waste slurry with solid content of 10-35% and settled for 1-48 h, and then high-solid-content waste slurry with solid content of 55-60% can be obtained through separation, so that the process of resource utilization of solid waste is simplified, the production cost of enterprises is reduced, and good cost reduction and effect enhancement effects are achieved; the settling efficiency of the waste slurry in the mixing plant can be effectively improved, the solid content of the settled waste slurry is increased, the solid content difference of the settled waste slurry in different batches is reduced, the waste slurry reduction is facilitated, and the green production of the mixing plant industry is realized.)

1. The waste slurry settling agent for the concrete mixing plant is characterized by comprising the following raw materials in parts by mass: 20-30 parts of a flocculating agent, 10-20 parts of a compacting agent and 5-10 parts of a surfactant;

wherein the flocculating agent is polyacrylamide or dimethyl diallyl ammonium chloride-acrylamide copolymer; the compacting agent is at least one of sodium polyacrylate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, maleic acid-acrylic acid copolymer and acrylic acid-acrylate-phosphoric acid-sulfonate quadripolymer.

2. The waste slurry settling agent for the concrete mixing plant according to claim 1, which comprises the following raw materials in parts by mass: 25 parts of flocculant, 15 parts of compacting agent and 7 parts of surfactant.

3. The concrete batching plant waste slurry settling agent as defined in claim 2, wherein said surfactant is an amino acid type gemini surfactant.

4. The concrete mixing plant waste slurry settling agent of claim 3, wherein said amino acid type gemini surfactant is

5. The concrete batching plant waste pulp settling agent as defined in claim 1 or 2, wherein said flocculant has a molecular weight of 1000 to 2000 ten thousand g/mol.

6. The concrete batching plant waste slurry settling agent according to claim 1 or 2, wherein said compacting agent has a molecular weight of between 100 and 500 ten thousand g/mol.

7. The concrete mixing station waste slurry settling agent of claim 1 or 2, wherein the total mass concentration of the flocculating agent, the compacting agent and the surfactant in the concrete mixing station waste slurry settling agent is 0.1-0.5%, and the balance is water.

8. A method of preparing a waste slurry settling agent for a concrete mixing plant according to any one of claims 1 to 7, comprising the steps of: dissolving a flocculating agent in water to prepare a solution with the concentration of 0.05-0.1%, then adding a surfactant, stirring to dissolve and clear, and then adding a compacting agent to prepare a solution with the total mass concentration of the flocculating agent, the compacting agent and the surfactant of 0.1-0.5%.

9. The method of using a waste slurry settling agent for a concrete mixing plant according to any one of claims 1 to 7, comprising the steps of: mixing the waste slurry settling agent of the concrete mixing plant and the waste slurry of the concrete mixing plant according to the mass ratio of 1: 100-1000, uniformly stirring, naturally settling for 1-48 h, and then separating supernatant liquid and lower-layer waste slurry through mechanical treatment.

10. The use method of the waste slurry settling agent for the concrete mixing plant according to claim 9, wherein the mass ratio of the waste slurry settling agent for the concrete mixing plant to the waste slurry for the concrete mixing plant is 1: 500-800.

Technical Field

The invention relates to the technical field of waste slurry sedimentation and concentration of a concrete mixing plant, in particular to a waste slurry sedimentation agent of the concrete mixing plant and a preparation method and a use method thereof.

Background

The waste slurry of the concrete mixing plant is the residual product after cleaning the mixing main machine of the mixing plant, the inner part of the concrete mixing truck drum and separating concrete residual materials and separating sand and stones by a sand-stone separator. The waste slurry consists of solid slag (solid particles) and clear liquid, wherein the solid slag mainly comprises partial unhydrated gelled materials, hydration products, a small amount of solid particles such as stone powder, mud and the like; the waste slurry clarifying solution is a supernatant liquid of waste slurry after standing for a period of time, the pH value of the supernatant liquid is alkaline, in addition, the waste slurry containing soluble inorganic salts, additive ions and the like of concrete is a main kind generated by waste of a mixing plant, and the disposal of the waste slurry is not favorable, so that the environmental pollution is easily caused. Therefore, how to realize zero emission of the waste slurry of the mixing plant is an urgent problem to be solved in green production of the test mixing plant.

The waste slurry of the concrete mixing plant contains a large amount of sandstone aggregate and powder with certain hydration activity, and has recycling value. At present, the treatment of the waste slurry by the mixing plant is mainly to separate out supernatant liquor and lower layer waste slurry solid by natural sedimentation. In order to accelerate the sedimentation rate, inorganic flocculants such as polyaluminium chloride and polyaluminium sulfate or organic flocculants such as polyacrylamide are often added in the sedimentation process. However, the method cannot increase the solid content of the settled waste slurry, the solid content difference of the settled waste slurries of different batches is large, so that the waste slurry is difficult to recycle, and even clear water is often required to be added into a settling pond, so that the reduction is not realized, and the waste slurry is increased. In addition, because the standing time of the waste slurry after sedimentation in the actual production process is uncertain, when the standing time exceeds 7 days or longer, the waste slurry settled at the lower part is easy to harden, and the subsequent discharging of the waste slurry is influenced.

Disclosure of Invention

In view of the above disadvantages, the present invention provides a concrete mixing plant waste slurry settling agent, a preparation method and a use method thereof, which can effectively improve the waste slurry settling efficiency of a mixing plant, increase the solid content of the waste slurry after settling, reduce the solid content difference of the waste slurry after settling in different batches, contribute to waste slurry reduction, and achieve the purpose of green production in the mixing plant industry.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a waste slurry settling agent for a concrete mixing plant, which comprises the following raw materials in parts by mass: 20-30 parts of a flocculating agent, 10-20 parts of a compacting agent and 5-10 parts of a surfactant;

wherein the flocculating agent is polyacrylamide or dimethyl diallyl ammonium chloride-acrylamide copolymer; the compacting agent is at least one of sodium polyacrylate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, maleic acid-acrylic acid copolymer and acrylic acid-acrylate-phosphoric acid-sulfonate quadripolymer.

Further, the waste slurry settling agent for the concrete mixing plant comprises the following raw materials in parts by mass: 25 parts of flocculant, 15 parts of compacting agent and 7 parts of surfactant.

Further, the surfactant is an amino acid type gemini surfactant.

Further, the amino acid type gemini surfactant is preferably one of the following two structures:

furthermore, the molecular weight of the flocculant is 1000-2000 ten thousand g/mol.

Furthermore, the molecular weight of the compacting agent is 100-500 ten thousand g/mol.

Further, the total mass concentration of the flocculating agent, the compacting agent and the surfactant in the waste slurry settling agent of the concrete mixing plant is 0.1-0.5%, and the balance is water.

The invention also provides a preparation method of the waste slurry settling agent for the concrete mixing plant, which comprises the following steps: dissolving a flocculating agent in water to prepare a solution with the concentration of 0.05-0.1%, then adding a surfactant, stirring to dissolve and clear, and then adding a compacting agent to prepare a solution with the total mass concentration of the flocculating agent, the compacting agent and the surfactant of 0.1-0.5%.

The invention also provides a use method of the waste slurry settling agent for the concrete mixing plant, which comprises the following steps: mixing the waste slurry settling agent of the concrete mixing plant and the waste slurry of the concrete mixing plant according to the mass ratio of 1: 100-1000, uniformly stirring, naturally settling for 1-48 h, and then separating supernatant liquid and lower-layer waste slurry through mechanical treatment.

Further, the parameters of stirring in the using method of the waste slurry settling agent of the concrete mixing plant are as follows: the stirring speed is 100-200 rpm; the stirring time is 5-10 min.

Further, the mass ratio of the waste slurry settling agent of the concrete mixing plant to the waste slurry of the concrete mixing plant is 1: 500-800.

The solid content of the waste slurry of the concrete mixing plant before sedimentation is 10-35%, and the solid content of the waste slurry after sedimentation is 55-60%.

In summary, the invention has the following advantages:

1. the invention provides a waste slurry settling agent for a concrete mixing plant, which is compared with the existing waste slurry settling agent, the existing waste slurry settling agent is mainly an inorganic or organic flocculating agent, is added into the waste slurry to enable particles to quickly settle after flocculation, but an agglomerated structure in the original waste slurry is also settled along with the particles, and water contained in the agglomerated structure is not released, so that the settling speed is only accelerated by adding the flocculating agent compared with a blank without adding the flocculating agent, and the solid content of the waste slurry after final settling balance is not increased. The compacting agent sodium polyacrylate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, maleic acid-acrylic acid copolymer and acrylic acid-acrylate-phosphoric acid-sulfonate in the waste pulp settling agent prepared by the invention have certain adsorption and dispersion effects on particles in the waste pulp, can break the aggregation structure of waste pulp particles, release more free water, and then rapidly settle under the flocculation effect of polyacrylamide or dimethyl diallyl ammonium chloride-acrylamide copolymer to obtain the waste pulp with higher particle compactness and higher solid content.

2. Amino and carboxyl contained in the amino acid type bi-surfactant used in the settling agent provided by the invention can be adsorbed on the surface of waste pulp particles through hydrogen bonds, and can form a cross-linked network structure under the synergistic action with amide bonds in the flocculating agent, so that the bridging effect among particles is enhanced, larger aggregates are formed, and the settling speed is further accelerated.

3. The settling agent has simple application method, the mixing amount is only 0.1-1% of the mass of the waste slurry, the waste slurry with the solid content of 55-60% can be obtained by applying the settling agent to the waste slurry of the mixing plant with different solid contents of 10-35%, the solid content difference of the settled waste slurry is small, the multi-batch unified treatment is facilitated, and the subsequent treatment process is simplified.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

Thus, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The preparation method of the waste slurry settling agent for the concrete mixing plant comprises the following steps:

20 parts of dimethyldiallylammonium chloride-acrylamide copolymer with the molecular weight of 1500 ten thousand g/mol is dissolved in 20000 parts of water, stirred until the mixture is clear, 10 parts of Gemini-A are added, 10 parts of acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer with the molecular weight of 200 ten thousand g/mol are added, and the mixture is stirred until the mixture is completely dissolved to obtain the settling agent.

Example 2

The preparation method of the waste slurry settling agent for the concrete mixing plant comprises the following steps:

dissolving 25 parts of polyacrylamide with the molecular weight of 1000 ten thousand g/mol in 30000 parts of water, stirring until the solution is clear, adding 10 parts of Gemini-A, then adding 5 parts of acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer with the molecular weight of 200 ten thousand g/mol and 10 parts of sodium polyacrylate with the molecular weight of 300 ten thousand g/mol, and stirring until the solution is completely clear to obtain the settling agent.

Example 3

The preparation method of the waste slurry settling agent for the concrete mixing plant comprises the following steps:

dissolving 20 parts of polyacrylamide with the molecular weight of 2000 ten thousand g/mol and 5 parts of dimethyldiallylammonium chloride-acrylamide with the molecular weight of 1500 ten thousand g/mol in 40000 parts of water, stirring until the mixture is clear, adding 15 parts of Gemini-B, then adding 10 parts of acrylic acid-acrylate-phosphoric acid-sulfonate quadripolymer with the molecular weight of 100 ten thousand g/mol and 10 parts of sodium polyacrylate with the molecular weight of 300 ten thousand g/mol, and stirring until the mixture is completely dissolved to obtain the settling agent.

Example 4

The preparation method of the waste slurry settling agent for the concrete mixing plant comprises the following steps:

10 parts of polyacrylamide with the molecular weight of 2000 ten thousand g/mol and 15 parts of dimethyldiallylammonium chloride-acrylamide with the molecular weight of 2000 ten thousand g/mol are dissolved in 40000 parts of water, stirred until the mixture is clear, 20 parts of Gemini-B are added, 10 parts of hydrolytic polymaleic anhydride with the molecular weight of 100 ten thousand g/mol and 10 parts of maleic acid-acrylic acid copolymer with the molecular weight of 200 ten thousand g/mol are added, and the mixture is stirred until the mixture is completely dissolved to obtain the settling agent.

Example 5

The preparation method of the waste slurry settling agent for the concrete mixing plant comprises the following steps:

5 parts of polyacrylamide with the molecular weight of 1500 ten thousand g/mol and 20 parts of dimethyldiallylammonium chloride-acrylamide with the molecular weight of 2000 ten thousand g/mol are dissolved in 30000 parts of water and stirred until the mixture is clear, 15 parts of Gemini-A are added, 10 parts of hydrolytic polymaleic anhydride with the molecular weight of 100 ten thousand g/mol and 10 parts of maleic acid-acrylic acid copolymer with the molecular weight of 200 ten thousand g/mol are added, and the mixture is stirred until the mixture is completely dissolved to obtain the settling agent.

Example 6

The preparation method of the waste slurry settling agent for the concrete mixing plant comprises the following steps:

5 parts of polyacrylamide with the molecular weight of 1500 ten thousand g/mol and 20 parts of dimethyldiallylammonium chloride-acrylamide with the molecular weight of 2000 ten thousand g/mol are dissolved in 30000 parts of water, stirred until the mixture is clear, 10 parts of Gemini-B are added, 20 parts of sodium polyacrylate with the molecular weight of 300 ten thousand g/mol are added, and the mixture is stirred until the mixture is completely clear to obtain the settling agent.

Comparative example 1

20 parts of dimethyldiallylammonium chloride-acrylamide copolymer with the molecular weight of 1500 ten thousand g/mol are dissolved in 20000 parts of water and stirred until the mixture is clear, thus obtaining the settling agent.

Comparative example 2

Dissolving 20 parts of dimethyldiallylammonium chloride-acrylamide copolymer with the molecular weight of 1500 ten thousand g/mol in 20000 parts of water, stirring until the mixture is clear, adding 10 parts of Gemini-A, and stirring until the mixture is clear to obtain the settling agent.

Comparative example 3

20 parts of dimethyldiallylammonium chloride-acrylamide copolymer with the molecular weight of 1500 ten thousand g/mol are dissolved in 20000 parts of water, stirred until the mixture is clear, 10 parts of acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer with the molecular weight of 200 ten thousand g/mol are added, and the mixture is stirred until the mixture is completely dissolved to obtain the settling agent.

Comparative example 4

Dissolving 10 parts of Gemini-A in 2000 parts of water, and stirring until the mixture is clear to obtain the settling agent.

Comparative example 5

10 parts of acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer with the molecular weight of 200 ten thousand g/mol are dissolved in 2000 parts of water and stirred until the mixture is clear, so that the settling agent is obtained.

Experimental example 1

Mixing 2g of the concrete mixing station waste slurry settling agent in the embodiment with 1000g of mixing station waste slurry with the solid content of 30% in a 1L beaker, stirring at the rotating speed of 150rpm for 5min, naturally settling, sucking out clear water at the upper layer after settling for 1 hour, 6 hours and 24 hours, taking 50g of waste slurry for testing the solid content, respectively numbering w1, w6 and w24, pouring out the clear water at the upper layer and the waste slurry at the lower layer after settling for 7 days, and recording the height of the hardened slurry which cannot be poured out from the bottom of the beaker. In this example, the sedimentation effects of examples 1 to 6 and comparative examples 1 to 5 were examined, and the results are shown in Table 1.

TABLE 1 sedimentation Effect of the blank examples, examples 1 to 6 and comparative examples 1 to 5

According to the data of the examples 1-6 and the blank examples in the data of the table 1, compared with the blank examples, the settling rates of different settling agents on the waste slurry are all improved, and the solid content of the waste slurry can be improved by 10-15% after settling for 24 hours. The data of comparative example 1 show that the flocculant alone increased the early settling rate, but not 24h solids. Comparative example 2 shows that the flocculant and the surfactant can improve the early-stage sedimentation velocity, but the solid content is not obviously improved within 24 hours; comparative example 4 shows that the settling rate of the surfactant alone and the solid content of the settled waste slurry are not increased; comparative example 3 shows that the flocculant solid thickening agent can increase the settling velocity and the solid content of the settled waste slurry, but the solid content is slightly lower than that of examples 1-6, and comparative example 5 shows that the single solid thickening agent can not increase the settling velocity nor increase the solid content of the settled waste slurry. It can be seen from the above results that the amino acid type gemini surfactant can reduce the amount of the waste pulp hardened at the bottom of the beaker and suppress the hardening of the waste pulp. The comparison result shows that the three components in the settling agent have synergistic effect, and compared with the single addition or the combination of two components of the three components, the combination of the three components can obviously improve the settling speed of the waste slurry and the solid content and the hardening inhibition after the settling.

Experimental example 2

2g of the settling agent obtained in example 6 was mixed with 1000g of waste slurry containing 10% (number group 1), 15% (number group 2), 20% (number group 3), 25% (number group 4), 30% (number group 5) and 35% (number group 6) in a 1L beaker, and stirred at 150rpm for 5min, followed by natural settling, followed by settling for 1 hour, 6 hours and 24 hours, respectively, to remove the upper clear water, 50g of the waste slurry was tested for solid content, and the settling time was 7 days, followed by pouring out the upper clear water and the lower waste slurry, respectively numbered w1, w6 and w24, and the hardened height at which the bottom of the beaker could not be poured out was recorded. The test results are shown in Table 2.

TABLE 2 test results

As can be seen from the test data in Table 2, the solid contents of the settled waste slurry with different initial solid contents are all 55-60%, and the solid content difference of the waste slurry is small, so that the method is beneficial to multi-batch unified treatment and can simplify the subsequent treatment process.

The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to supplement or replace the specific embodiments described by those skilled in the art without inventive faculty.