Advantages and Selection of Defoamer


Release time:

2016-06-27

Author:

New Earth Group

Source:

Advantages and Selection of Defoamer

Defoamers are widely used in various industries, mainly because defoamers have the following four advantages in the process of use:
1. Fast defoaming: After use, the foam can be quickly eliminated, which can reduce the impact of harmful substances on the environment. In the process of defoaming, it can quickly play a role in defoaming, and after use, it can also The appearance of its foam has a certain suppression effect and improves the performance of use.
2. simple to use: in the process of use is very simple, only need to be placed in the water can be used. In addition, nonionic surfactants are widely used and can improve the efficiency of industrial production.
3. Wide range of application: In the process of use, it can be used in various environments, and it will not be unable to use due to the influence of the environment. It can be used in high temperature, high pressure and other environments.
4. Storage safety: in the process of not using, it can also be stored safely, can be stored for a long time without damage, improve the elimination of foam on the surface of the article, and improve the effect of use.
The production of foam is mostly under the action of external force, the surface active substances contained in the solution and air at the junction of the formation of foam and floating or such as gelatin, protein and other colloidal substances into a film caused by foam, defoaming agent is in the production process can reduce the surface tension, the elimination of foam material. Proper use of defoaming agent: the choice of defoaming agent should be targeted, and the use environment, temperature, PH value and foaming medium should be understood. First small test, after the pilot test, to determine the best use of products and the best dosage. After stratification, stir well first. Even if there is no stratification, stir well before use. Do not dilute at will. If you really want to dilute, please use thick aqueous solution under guidance.
Select the defoamer to meet the following points:
1. Insoluble or insoluble in foaming liquid
In order to burst the foam, the defoamer should be concentrated and concentrated on the bubble film. In the case of foam breakers, they should be concentrated and concentrated in an instant, and in the case of foam suppression, they should always be kept in this state. Therefore, the defoaming agent is in a supersaturated state in the foaming liquid, and only insoluble or insoluble is easy to reach a supersaturated state. Insoluble or insoluble, it is easy to gather at the gas-liquid interface, it is easy to concentrate on the bubble film, in order to play a role at a lower concentration. For the defoaming agent in the water system, the molecules of the active ingredient must be strong hydrophobic and weak hydrophilic, and the HLB value is in the range of 1.5-3, so the effect is the best.
2, the surface tension is lower than the bubble liquid.
Only when the intermolecular force of the defoamer is small and the surface tension is lower than that of the foaming liquid, the defoamer particles can be immersed and expanded on the bubble film. It is worth noting that the surface tension of the foaming solution is not the surface tension of the solution, but the surface tension of the foaming solution.
3, and the bubble liquid has a certain degree of affinity.
Since the defoaming process is actually a competition between the speed of foam collapse and the speed of foam generation, the defoaming agent must be able to be rapidly dispersed in the foaming liquid in order to quickly function in a wider range of foaming liquid. In order to make the defoamer diffuse faster, the active ingredient of the defoamer must have a certain degree of affinity with the foaming liquid. The active ingredient of defoamer is too close to the foaming liquid and will dissolve; it is too sparse and difficult to disperse. The effectiveness will be good only if the closeness is appropriate.
4. There is no chemical reaction with the foaming liquid.
The defoaming agent reacts with the foaming liquid. On the one hand, the defoaming agent will lose its effect. On the other hand, it may produce harmful substances and affect the growth of microorganisms.
5. Small volatility and long action time.
First of all, it is necessary to determine the system that needs to use defoamers, which is an aqueous system or an oily system. Such as the fermentation industry, it is necessary to use oily defoamers, such as polyether modified silicon or polyether. Water-based coatings industry will use water-based defoamers, silicone defoamers. Select the defoamer, compare the amount of addition, in the reference price, can be the most applicable and most economical defoamer products.

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