Contents of this article
What kind of water-reducing agent does lignin-based water-reducing agent belong to?
What are the ingredients of water reducing agent?
What are the main uses of industrial lignin?
Which retarding water reducing agent is the best?
What are the water reducing agents?
What are the main ingredients of the water reducing agent used in concrete?
What is concrete binder?
What kind of water-reducing agent does lignin-based water-reducing agent belong to?
It is a sodium lignosulfonate water-reducing agent. Sodium lignosulfonate water-reducing agent is a modified sodium lignosulfonate, a powdery low-air-entraining retarding water-reducing agent. It is an anionic surface-active substance that has adsorption and dispersion effects on cement and can improve various aspects of concrete. physical properties.
It can be compounded into early strength agent, retardant, antifreeze, pumping agent, etc. The liquid admixture made after compounding with naphthalene series high-efficiency water reducing agent has basically no precipitation. Comply with national standards for concrete admixtures.
What are the ingredients of water reducing agent?
Contains lignin. The component of the water-reducing agent is lignin, which is generally extracted from coniferous trees. Lignin is polymerized from three lignin monomers: p-peranyl alcohol, coniferyl alcohol, and sinapyl alcohol. It is an anionic surfactant and can be directly It can also be used as one of the raw materials of compound admixtures. Because of its low price, it is still widely used. When used in mortar, it can improve workability, fluidity, strength, and water reduction rate of 8%-10%.
What are the main uses of industrial lignin?
Main uses:
1. Used as concrete water-reducing agent: adding 0.2-0.3% of the weight of cement can reduce water consumption by more than 10-15% and improve the workability of concrete. , improve project quality. Used in summer, it can suppress slump loss and is generally used in combination with high-efficiency water reducing agents.
2. Used as mineral processing flotation agent and smelting mineral powder binder. In the smelting industry, calcium lignosulfonate is mixed with mineral powder to make mineral powder balls. After drying, it can be put into the kiln. Improve smelting recovery rate.
3. Refractory materials: When manufacturing refractory bricks and tiles, calcium lignosulfonate is used as a dispersant and adhesive, which can improve operating performance, and has the functions of reducing water, strengthening, and preventing cracks. Effect.
4. Ceramics: Used in ceramic products, it can reduce the carbon content and increase the strength of the green body, reduce the amount of plastic clay, improve the fluidity of the mud, increase the yield of finished products by 70-90%, and reduce the sintering speed from 70 minutes to 40 minutes. minute.
5. Others: Calcium lignosulfonate can also be used as refining aids, casting, coal-water slurry dispersant, pesticide wettable powder processing, briquette suppression, road, soil, dust suppression, manufacturing Leather tanning filler, carbon black granulation, feed binder, etc. Sodium lignosulfonate is an anionic surfactant, brown powder. It is mainly used for the dispersion and filling of disperse dyes and vat dyes. It has good dispersion, heat-resistant stability and high-temperature dispersion. It has good grinding aid effect, has light staining on fibers, and has little reducing effect on azo dyes.
Which retarding water reducing agent is the best?
Lignin sulfonate is the best.
Lignosulfonate is a by-product of sulfite pulping. The molecular weight of lignosulfonate is 2000~5000, and the sulfonate group is 1.25~2.5mcq/g. It is soluble in aqueous solutions with various pH values and insoluble in organic solvents. The functional group is phenolic hydroxyl group. Its raw material is lignin, which is generally extracted from coniferous trees. Lignin is polymerized from three lignin monomers: p-peranyl alcohol, coniferyl alcohol, and sinapyl alcohol, including: calcium lignosulfonate, lignosulfonate Sodium phosphate, magnesium lignosulfonate.
What are the water reducing agents?
The main water reducing agents include: Lignin is the third most abundant organic substance on earth after cellulose and chitin. The main active ingredients are various lignin derivatives extracted from the pulp waste liquid of grass and woody plants, including lignin sulfonate, sulfate lignin, alkali lignin, etc.
Due to the abundant sources of raw materials, simple processing, low selling price, and stable performance, it is the main variety among ordinary water-reducing agents and has a large production and application volume.
Secondly, humic acid superplasticizer is a substance extracted from grass ash, peat, and lignite. Its main component is sodium humate. Some of them have been sulfonated to become polysulfonic acid-based. substance. Because humic acid superplasticizer has many impurities, its quality is not stable enough, its output is small, and its application volume is not large.
Lastly, sugar calcium water-reducing agent is a powder or liquid product made by using the residual liquid left after refining edible sugar in the sugar production process and neutralizing it with lime. It has abundant sources, simple preparation and low price, so it is currently widely used.
What are the main components of the water reducing agent used in concrete?
The water reduction rate of pulp waste liquid, the main component of sodium lignosulfonate, is 10% to 15%; the 28d strength is increased by 10% to 20%; the slump is increased by 100 to 150㎜ 0.2 to 0.3 MY type reducer The main component of the water agent is lignocalcium derivatives, pH 8 ~ 9, powdery water reduction rate 9% ~ 12%; 3d and 28d strength increased by 15%; air entrainment capacity 3% ~ 4% 0.2 ~ 0.3 GF-G type water reducing agent mainly The water reduction rate of magnesium lignosulfonate is 8%; the 3d and 28d strength is increased by 12% 0.4
What is the concrete binder?
Concrete admixtures are substances added during the concrete mixing process to improve the properties of concrete. The dosage should not exceed 5% of the cement mass (except for special circumstances).
1. Classification of concrete admixtures
National standard GB8075-87Sodium alkyl sulfonate and sodium alkyl benzene sulfonate, etc.
(4) Retarder
Admixtures that extend the setting time of concrete are called retarder. In concrete construction, in order to prevent the premature setting of the concrete mixture from affecting the pouring quality under conditions such as high temperatures and long transportation distances, in order to extend the heat release time of large-volume concrete or prevent construction cracks in concrete poured in layers For projects, it is often necessary to add retarder to concrete.
(5) Antifreeze
Admixtures that can harden concrete at negative temperatures and achieve sufficient antifreeze strength within a specified time are called antifreeze. Antifreeze must be added to concrete projects constructed under negative temperature conditions. Generally, in addition to lowering the freezing point, antifreeze also has the functions of accelerating coagulation, early strength, and water reduction, so it is mostly a compound antifreeze. Commonly used ones include NC-3 type, MN-F type, FW2, FW3, AN-4, etc. </p
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