CN104098289B - A kind of collapse protection type concrete pump-feed agent of admixture CLT acid waste liquid - Google Patents

Abstract

The invention belongs to the technical field of building materials, and in particular relates to a slump-preserving concrete pumping agent mixed with CLT acid waste liquid. The raw materials used in the present invention are: CLT acid waste liquid, lignosulfonate water reducer, high-efficiency water reducer, defoamer, cellulose ether and water. Using the present invention can greatly improve the fluidity of concrete, Reduce the amount of high-efficiency water reducer, so that the concrete slump will not be lost within 2-3 hours, reduce bleeding, and improve concrete strength and durability. The invention is suitable for commercial ready-mixed concrete, self-compacting concrete and pumped concrete. The invention has the advantages of simple preparation process, low cost, stable product performance, full use of CLT acid waste liquid, and good economic and social benefits.

Description

A kind of slump-preserving concrete pumping agent mixed with CLT acid waste liquid

technical field

The invention belongs to the technical field of building materials, and in particular relates to a slump-preserving concrete pumping agent mixed with CLT acid waste liquid.

Background technique

The development of commercial concrete has greatly promoted the centralized production and supply of concrete and the progress of pumping construction technology. At the same time, it has ensured the quality of the project and improved the bulk rate of cement. It is one of the important links for energy saving and consumption reduction in the construction industry. Commercial concrete is transported and poured along the pipeline under the impetus of the pump. In addition to meeting the strength, durability and economy indicators specified in the design, it must also meet the fluidity retention during transportation and the impact of the pipeline transportation process. Special requirements for the properties of the mixture, namely pumpability. As an admixture to improve the pumping performance of concrete, the pumping agent has excellent water-reducing and enhancing effects and retarding and plastic-retaining properties, and is an essential component for preparing ready-to-use concrete.

The composition of the pumping agent usually includes water-reducing components, retarding components, air-entraining components and water-retaining components. Among them, the water reducing agent is the most important component, and the pumping agent is often defined by its water reducing effect. In addition, retarders, air-entraining agents and water-retaining agents often become one of the components of pumping agents. Due to the need for long-distance transportation, commercial concrete often needs to delay its slump loss as much as possible, especially for large-volume concrete or high-temperature construction projects in summer, so retarders must be added. Appropriate air content can reduce the pumping resistance during concrete pumping, prevent concrete bleeding and segregation, and at the same time improve the ability of concrete to resist freeze-thaw cycle damage. The function of the water retaining agent is to increase the viscosity of the concrete mixture, so that the concrete will not bleed or segregate under the condition of low cementitious material dosage and large slump.

6-Chloro-3-aminotoluene-4-sulfonic acid, referred to as CLT acid (or methyl C acid), is an important intermediate for the synthesis of red organic pigments and an organic dye intermediate with an annual consumption of more than 10,000 tons in the world one. From the perspective of geographical distribution, Asia is already the concentration of CLT acid production enterprises in the world, and my country is the country with the largest CLT acid production capacity in the world today. The total amount of domestic CLT acid has exceeded 90% of the global market. At present, the main method used to synthesize CLT acid at home and abroad is the toluene sulfonation route. In the production process of CLT acid, through several processes such as sulfonation, chlorination, nitration, neutralization, reduction, acid precipitation, etc., produced A large amount of CLT acid waste liquid, the reaction equation of synthetic CLT acid by toluene sulfonation method is as follows:

CLT acid waste liquid is a reddish-brown transparent liquid in appearance, and its typical waste water quality indicators are: COD=(20000-30000) mg/L, BOD ₅ =(1500-2500) mg/L, pH=1-3 , NH ₃ -N = (350-400) mg/L, Cl ^- = (16000-20000) mg/L. The waste liquid contains high concentration of inorganic salts, among which the total content of Cl ^- , Ca ²⁺ and Fe ²⁺ is about 30g/L. Therefore, CLT acid waste liquid is a high-concentration, high-salt, non-biochemical organic waste liquid.

Contents of the invention

The purpose of the present invention is to provide a slump-preserving concrete pumping agent mixed with CLT acid waste liquid, the pumping agent can significantly improve the slump retention of concrete mixture, improve the durability of concrete, and has a preparation process Simple, little impact on concrete strength and low cost.

A kind of slump-retaining concrete pumping agent mixed with CLT acid waste liquid proposed by the present invention is composed of CLT acid waste liquid, lignosulfonate water reducer, high-efficiency water reducer, defoamer, cellulose ether and water Composition, the weight ratio of each component is:

CLT acid waste liquid 100

Lignosulfonate superplasticizer 5-15

Superplasticizer 150-900

Defoamer 0.1-0.5

Cellulose ether 5-15

Water 2300-9500.

In the present invention, when the components are solutions, their weight ratio is the weight ratio after folding.

In the present invention, the CLT acid waste liquid is produced during the preparation of CLT acid by the toluene sulfonation method.

In the present invention, the lignosulfonate water reducer is one of calcium lignosulfonate water reducer, sodium lignosulfonate water reducer or magnesium lignosulfonate water reducer.

In the present invention, the superplasticizer is one of naphthalene-based superplasticizers or aliphatic superplasticizers.

In the present invention, the defoamer is a water-soluble defoamer.

In the present invention, the cellulose ether is hydroxypropyl methylcellulose ether with a viscosity of 100,000 mPa·s.

The preparation method of the slump-retaining concrete pumping agent mixed with CLT acid waste liquid proposed by the present invention is as follows: weighing each component according to the aforementioned weight ratios, first adding water to the mixer, and then adding CLT acid The waste liquid, lignosulfonate water reducer, superplasticizer, defoamer and cellulose ether are sequentially added into the mixer for stirring and dissolving for 1-3 hours to obtain the desired product.

In the present invention, the CLT acid waste liquid plays the roles of water reduction, retardation and air entrainment at the same time, and plays an important positive role in the slump retention and pumpability of the concrete mixture. The presence of lignosulfonate superplasticizer can significantly reduce the slump loss of concrete, but the dosage should not be too high, otherwise it will adversely affect the development of concrete strength. The high-efficiency water reducer is the main water reducing component in the present invention. It is an anionic surfactant, and it works together with CLT acid waste liquid to disperse cement. Introducing a large number of tiny air bubbles into the concrete mixture helps to improve the fluidity and uniformity of the concrete and reduce the slump loss of the concrete. However, the air bubbles introduced by the CLT acid waste liquid not only include these beneficial tiny air bubbles, but also It also includes some large air bubbles that are harmful to the concrete strength. In the present invention, adding a certain amount of defoamer can not only eliminate these harmful large air bubbles, but also retain the introduced micro air bubbles. In most cases, concrete mixtures formulated with pumping agents have greater fluidity, and are very prone to stratification and segregation. Although this is beneficial to the slump retention of concrete mixtures, It is not conducive to the pumping of concrete. An effective way to solve this problem is to add water-retaining components to increase the viscosity of the concrete mixture. The present invention uses hydroxypropyl methylcellulose ether with a viscosity value of 100,000 mPa·s as the pump The water-retaining component of the delivery agent.

When the present invention is in use, its suitable dosage (consolidated dosage) in concrete is 0.4%-2.0% of the weight of the cementitious material, and the specific dosage is determined through tests according to the requirements of the prepared concrete. As a slump-preserving concrete pumping agent, the invention can effectively improve the fluidity and constructability of the concrete mixture, the water reducing rate can reach more than 20%, and the slump of the prepared concrete mixture is between 2- There is basically no loss within 3 hours, and the strength and durability are also greatly increased. It can be used to prepare concrete of various strength levels.

The invention uses CLT acid waste liquid as a raw material to prepare a slump-preserving concrete pumping agent. The preparation method is simple and effectively reduces the production cost, and is also beneficial to environmental protection and improvement of the discharge of three wastes, and has broad market prospects.

The present invention considers that the organic matter in the CLT acid waste liquid contains a large amount of amino groups and sulfonic acid groups, which belong to dianionic surfactants, and some polymers with a certain degree of polymerization will be generated in the CLT acid synthesis process, so the CLT acid waste liquid The chemical structure has the conditions to be used as a concrete admixture. For this reason, the present inventors have carried out relevant tests on the performance of CLT acid waste liquid in the early stage, and found that CLT acid waste liquid has a high mortar water-reducing rate, as well as significant retarding and air-entraining characteristics.

The present invention has just utilized the above-mentioned characteristics of CLT acid waste liquid, and proposes a kind of slump-preserving concrete pumping agent mixed with CLT acid waste liquid. The raw materials used in the invention include: CLT acid waste liquid, lignosulfonic acid Salt superplasticizer, superplasticizer, defoamer, cellulose ether and water. Among them, CLT acid waste liquid plays the role of reducing water, retarding and entraining air at the same time, supplemented by a small amount of lignosulfonate superplasticizer to improve the retarding effect of pumping agent, high-efficiency water reducer and CLT acid The waste liquid works together to reduce water. A certain amount of defoamer is added to eliminate the harmful large air bubbles introduced by the CLT acid waste liquid, while retaining the introduced fine air bubbles. The cellulose ether plays the role of water retention and viscosity increase. The invention has the advantages of simple preparation process, low cost, good slump retention, little influence on concrete strength, wide application range, good technical, economic and environmental effects, and broad market prospect.

detailed description

The present invention provides a slump-preserving concrete pumping agent technology mixed with CLT acid waste liquid. In order to make the purpose, technical scheme and effect of the present invention clearer and clearer, the present invention will be further described in detail below. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Example 1, a slump-preserving concrete pumping agent mixed with CLT acid waste liquid, 100% of CLT acid waste liquid, 5% of calcium lignosulfonate water reducer, 150% of naphthalene series high-efficiency water reducer, and 0.5% of defoamer , the weight ratio of cellulose ether 5 and water 2300 is weighed and then placed in a mixer for stirring and dissolving for 1 hour to obtain the required product, named PA-1, which has a good impact on the slump performance of concrete mixture and hardened concrete. The test results of strength influence are shown in Table 1.

Example 2, a slump-preserving concrete pumping agent mixed with CLT acid waste liquid, according to CLT acid waste liquid 100, sodium lignosulfonate water reducer 8, aliphatic high-efficiency water reducer 300, defoamer 0.3 , the weight ratio of cellulose ether 7 and water 3735 is weighed and then placed in a mixer for stirring and dissolving for 2 hours to obtain the desired product, named PA-2, which has a good effect on the slump performance of concrete mixture and the performance of hardened concrete. The test results of strength influence are shown in Table 1.

Example 3, a slump-preserving concrete pumping agent mixed with CLT acid waste liquid, according to CLT acid waste liquid 100, magnesium lignosulfonate water reducer 13, naphthalene series high-efficiency water reducer 600, defoamer 0.2 , the weight ratio of cellulose ether 12 and water 6525 is weighed and then placed in a mixer for stirring and dissolving for 2.5 hours to obtain the required product, named PA-3, which has a good impact on the slump performance and hardening properties of concrete mixtures. The test results of the influence of concrete strength are shown in Table 1.

Example 4, a slump-preserving concrete pumping agent mixed with CLT acid waste liquid, according to CLT acid waste liquid 100, calcium lignosulfonate water reducer 15, aliphatic high-efficiency water reducer 900, defoamer 0.1 , the weight ratio of cellulose ether 15 and water 9500 is weighed and placed in a mixer for stirring and dissolving for 3 hours to obtain the desired product, named PA-4, which has a good impact on the slump performance of concrete mixtures and hardened concrete. The test results of strength influence are shown in Table 1.

Table 1 embodiment performance test result

Note: 1. In order to ensure the comparability of the test results of each group, the same mix ratio is used for each group of concrete tests in Table 1: m (cement): m (mineral powder): m (river sand): m (stone): m (water) = 252:108:660:1000:136, among which the cement is Nanjing Onoda P·Ⅱ52.5 grade cement, the mineral powder is Shanghai Baotian S95 grade mineral powder, the fineness modulus of the river sand is 2.2, and the particle size of the stone is 5- 25mm continuous graded crushed stone, tap water is selected for water.

2. The high-efficiency water-reducers in Example 1 and Example 3 all use naphthalene-based high-efficiency water-reducers (abbreviation: NSF), so the performance of PA-1 and PA-3 is compared with NSF in the table, and the dosage (folded solid Dosage) are 0.9% of the gelling material;

3. The high-efficiency water-reducers in Examples 2 and 4 all use aliphatic high-efficiency water-reducers (abbreviated as: SAF), so the performance comparison between PA-2 and PA-4 and SAF is made in the table, and the dosage (folded solid Dosage) are 0.7% of the gelling material;

It should be noted that the application of the present invention is not limited to the above examples, and those skilled in the art can make improvements or transformations according to the above descriptions, and all these improvements and transformations should belong to the protection scope of the appended claims of the present invention.

Claims (7)

1. a collapse protection type concrete pump-feed agent for admixture CLT acid waste liquid, it is characterized in that being made up of CLT acid waste liquid, ligno-sulfate based plasticizer, high efficiency water reducing agent, defoamer, ether of cellulose and water, the weight ratio of each component is:

CLT acid waste liquid 100

Ligno-sulfate based plasticizer 5-15

High efficiency water reducing agent 150-900

Defoamer 0.1-0.5

Ether of cellulose 5-15

Water 2300-9500;

Wherein: described CLT acid waste liquid with toluene sulfonation legal system for CLT acid process in produce.

2. the collapse protection type concrete pump-feed agent of a kind of admixture CLT acid waste liquid according to claim 1, is characterized in that when described component is solution, and its weight ratio is roll over the weight ratio admittedly.

3. the collapse protection type concrete pump-feed agent of a kind of admixture CLT acid waste liquid according to claim 1, is characterized in that described ligno-sulfate based plasticizer is the one in calcium lignin sulfonate water depressor, sodium lignin sulfonate water reducer or magnesium lignosulfonate water reducer.

4. the collapse protection type concrete pump-feed agent of a kind of admixture CLT acid waste liquid according to claim 1, is characterized in that described high efficiency water reducing agent is the one in naphthalene series high-efficiency water-reducing agent or aliphatic high-efficiency water reducing agent.

5. the collapse protection type concrete pump-feed agent of a kind of admixture CLT acid waste liquid according to claim 1, is characterized in that described defoamer is water insoluble defoamer.

6. the collapse protection type concrete pump-feed agent of a kind of admixture CLT acid waste liquid according to claim 1, it is characterized in that described ether of cellulose is hydroxypropyl methyl cellulose ether, viscosity is 100,000 mPas.

7. the preparation method of the collapse protection type concrete pump-feed agent of an a kind of admixture CLT acid waste liquid as claimed in claim 1, it is characterized in that concrete steps are: weigh each component in proportion, first water is added in mixing machine, again CLT acid waste liquid, ligno-sulfate based plasticizer, high efficiency water reducing agent, defoamer and ether of cellulose are added in mixing machine successively and carry out stirring, dissolving 1-3h, obtain desired product.