In the industrial production process, due to formula and process reasons, foam problems are inevitable. Foam may cause environmental pollution, affect product quality and other negative effects. Usually, the common solution in the industry is to add a defoamer for defoaming and foam suppression. Defoamers are widely used in industrial production, with small additions and obvious defoaming effects. This article briefly introduces the hazards of foam and the four major defoaming mechanisms of defoamers.
(Picture: Application of defoamer in paper industry)
The harm of bubbles
In industrial production, in order to ensure certain special properties of the product, such as cleaning, lubrication, rust prevention and other functions, it is usually necessary to add corresponding additives for preparation. However, many additives are surfactants and are used in production. Some high-speed mixing processes are prone to a large amount of foam.
Common hazards of industrial production foam:
1. Affect product quality
Such as: textile high-temperature printing and dyeing process, foam will affect the effect of dyeing and printing; such as: in water-based coating process, foam will affect the function of the coating film, causing defects such as shrinkage or fish eyes in the coating film, affecting the aesthetics of construction; such as: papermaking In production, the foam in the pulp easily affects the formation of paper, resulting in holes on it, which affects the quality of paper products.
(Picture: Defoamer eliminates bubbles in paper production)
2. Affect system operation
For example, in the desulfurization process, the slurry foam of the desulfurization tower is likely to cause slurry overflow, false liquid level, etc., which affect the judgment of the staff, seriously affect the operation of the system, and cause more serious negative effects.
3. Pollute the environment
For example, industrial water treatment foam will not only increase the difficulty and cost of sewage treatment, but the direct discharge of foam will pollute the surrounding environment.
Harmful bubbles are serious and need to be controlled and eliminated as soon as possible. To eliminate foam, adding defoamer is a very common method.
Four defoaming mechanisms of defoamers
Defoamers are widely used and can quickly eliminate harmful foams. The main defoaming principles are as follows:
1. The defoaming mechanism of solid particles
The primary condition for solid particles as defoamers is that the solid surface must be hydrophobic. Such as hydrophobic silica solid particles which defoam.
2. The defoamer reduces the local surface tension of the foam liquid film and defoams
Because the surface tension of the defoamer droplets is lower than that of the foam liquid film. When the defoamer is added to the foam system, the contact between the defoamer droplets and the foam droplets can reduce the surface tension of the liquid film here. The surface tension of the liquid film around the foam hardly changes. The part with reduced surface tension is strongly pulled around, stretched and finally bursts to eliminate the foam.
(Picture: Defoamer foam breaking principle)
3. The defoaming agent destroys the elasticity of the film and the liquid film loses its self-repairing effect and defoams
Add defoamers with extremely low surface tension such as polyoxyethylene polysiloxane defoamers into the foam system. After this defoamer enters the foam liquid film, it will reduce the surface tension of the liquid film to an extremely low level. When the liquid film here is subject to external disturbance or impact, the area A of the liquid film will increase, reducing the concentration of the defoamer here, causing the surface tension of the liquid film to rise, but the surface tension of the defoaming agent itself is too high. Low, unable to make d Y/dA have a high value, and make the film lose its elasticity. The liquid film will not produce effective elastic contraction force to restore the surface tension and thickness of the film. The liquid film will eventually lose its self-repairing effect. destroyed.
4. The defoamer reduces the viscosity of the liquid film to shorten the foam life and defoam
The high surface viscosity of the foam liquid film will increase the strength of the liquid film, slow down the drainage speed of the liquid film, reduce the air permeability of the liquid film and prevent the gas diffusion in the bubble, and extend the life of the foam to stabilize the foam. Foam stabilizers with conditions for generating hydrogen bonds, such as: the ether bond of polyether surfactants can form hydrogen bonds with water at low temperatures, and the peptide prion bonds of proteins can form hydrogen bonds to increase the surface viscosity of the liquid film. If a defoamer that can not generate hydrogen bonds is used to replace the foam stabilizer that can generate hydrogen bonds from the surface of the liquid film, the viscosity of the liquid film surface will be reduced, and the drainage speed and gas diffusion speed of the foam liquid film will be accelerated and reduced. The life of the foam is defoamed.
The defoamer mainly defoams by the above defoaming principle. Although defoaming agent has the advantages of wide application and small dosage, it also has strong pertinence. Therefore, Nanhui defoaming agent manufacturers here remind everyone of the manufacturers to choose defoaming agents for defoaming and avoid buying The defoamer cannot solve the embarrassing problem.
The source manufacturer of Nanhui defoamer is located in Dongguan, Guangdong. It has strong R&D strength, professional defoaming technology, various formulas, rich industry application experience, and good customer feedback. Provide on-demand customized services, design defoaming solutions for your industry and the cause of foaming, with strong defoaming power, good foam suppression, and ideal defoaming effects.
(Picture: Nanhui defoamer sample)
Nanhui is a manufacturer with years of application experience. It has far more defoaming technology than other antifoaming agents in the market. From the above cases, we prove the strength of our Nanhui defoamer. We have a group of excellent defoaming engineers, and an independent laboratory that facilitates defoaming experiments with foams that are difficult for customers to solve. If you want to know more about defoamer products, you can call our hotline: +86 13428601010.
This article is from the manufacturer of Nanhui defoamer (http://www.nhdefoamer.com/), please indicate the source if you need to reprint.
