Guide to the use of water-based non-silicon defoamers: a full-process analysis from preparation to application
In industrial production and daily applications, water-based non-silicon defoamers are effective tools for solving foam
problems. However, if used improperly, not only will the expected defoaming effect fail to be achieved, but it may also
affect product quality and production efficiency. Only by mastering scientific and standardized usage methods can
water-based non-silicon defoamers give full play to their effectiveness. Next, we will introduce the whole process of
its use in detail.
I. Preparation before use
(I) Understanding system characteristics
Before using water-based non-silicon defoamers, you must fully understand the characteristics of the system that needs
to be defoamed. The first is the acidity and alkalinity (pH value) of the system. Different water-based non-silicon defoamers
have different stability and defoaming effects under different pH environments. For example, some defoamers can maintain
good activity in a weakly acidic environment, but may fail in a strongly alkaline environment. Secondly, it is necessary to
clarify the temperature range of the system, because temperature will affect the dispersibility and defoaming speed of the
defoamer. Some water-based non-silicon defoamers are easy to volatilize or decompose in a high temperature environment,
thereby reducing the defoaming performance. In addition, it is also necessary to understand the composition of the system,
such as whether it contains special surfactants, polymers, etc., to avoid adverse reactions between the defoamer and other
components in the system.
(II) Choose the right product
According to the characteristics of the system, it is crucial to choose a matching water-based non-silicon defoamer. There are
many types of water-based non-silicon defoamers on the market, and each product has its applicable fields and characteristics.
If it is in the food processing industry, you should choose a water-based non-silicon defoamer that meets the food additive
standards and is non-toxic and harmless; for the coatings industry, you need to choose a product that will not affect the
film-forming properties of the coating and has good compatibility; in the field of sewage treatment, you need to choose a
defoamer that can adapt to complex water quality and has strong defoaming and anti-foaming capabilities. At the same time,
you can evaluate the effects of different defoamers in the actual system through small sample tests, so as to select the most
suitable product.
II. Addition method and dosage control
(I) Addition method
Direct addition: For some simple water-based systems, the water-based non-silicon defoamer can be added directly to the location
where the foam is generated. For example, in a small laboratory experiment or a simple stirring process, the
foam generated can be measured with a dropper or a measuring cylinder to measure the appropriate amount of defoamer, directly
added to the foam system, and then stirred and mixed to make it disperse quickly and work.
Add after dilution: When the system is large or the concentration of the defoamer is high, in order to ensure that the defoamer can
be more evenly dispersed in the system, the water-based non-silicon defoamer can be diluted with an appropriate amount of water.
The dilution ratio can be adjusted according to the product manual and actual conditions, and is generally controlled between
1:5 - 1:10. The diluted defoamer is slowly added to the production system through a pipeline or a metering pump, and stirred or
circulated to ensure that it is fully dispersed.
Add in stages: In some scenarios where the production process is long and foam is prone to repeated generation, such as pulping
and coating processes in papermaking, the segmented addition method can be adopted. A certain amount of defoamer is added in
the initial stage of production for early defoaming, and then in key links, such as slurry concentration, coating liquid preparation,
etc., the defoamer is added again to continuously suppress the generation of foam.
(II) Dosage control
The amount of water-based non-silicon defoamer is not the more the better. Excessive use will not only increase costs, but may also
have a negative impact on the system, such as affecting product performance or causing new problems. Generally speaking, the
recommended dosage of defoamer is between 0.1% and 1% (as a percentage of the total system). In actual use, it should be
fine-tuned according to the severity of the foam, the nature of the system, and the performance of the defoamer. For example,
for systems with less foam and easy to eliminate, a lower dosage can be used; while for systems with rich foam and difficult to
eliminate, the dosage needs to be appropriately increased. Before starting large-scale use, be sure to conduct a pilot or small
test to determine the optimal dosage by observing the defoaming effect and product quality.
III. Precautions during use
(I) Mixing and dispersion
After adding the water-based non-silicon defoamer, ensure that it is fully mixed and dispersed in the system. Good dispersibility
enables the defoamer to fully contact with the foam and improve the defoaming efficiency. This can be achieved by strengthening
stirring, extending the stirring time, or using special dispersing equipment. In the production of coatings, after adding the defoamer,
it is usually necessary to stir at high speed for 10-15 minutes to evenly distribute the defoamer in the coating system. However,
it should be noted that the stirring speed should not be too fast to avoid generating new foam.
(II) Temperature and time control
During use, the temperature of the system and the action time of the defoamer should be strictly controlled. If the system temperature
is too high, the effective ingredients of the defoamer may volatilize or decompose, reducing the defoaming effect; if the temperature
is too low, the dispersibility and activity of the defoamer may be affected. At the same time, it takes a certain amount of time for the
defoamer to take effect. Do not rush to the next step after adding it. Wait for enough time for the defoamer to fully play its role. For
example, in sewage treatment, it is necessary to observe for 15-30 minutes after adding the defoamer to confirm that the foam is
completely eliminated or effectively suppressed before continuing with the subsequent treatment process.
IV. Monitoring and adjustment after use
After using the water-based non-silicon defoamer, the system should be continuously monitored. Observe whether the foam is
generated again and whether the quality of the product is affected. If the foam suppression effect is not ideal, it may be due to
insufficient dosage, uneven dispersion, or mismatch between the defoamer and the system. You need to adjust the usage method
or replace the product in time. At the same time, record the relevant data of each use of the defoamer, such as dosage, addition
method, and usage effect, to provide a reference for subsequent production and optimization.
The correct use of water-based non-silicon defoamers requires strict control of all links from preliminary preparation, addition
process to later monitoring. Only by mastering the scientific usage method can we give full play to its defoaming and anti-foaming
advantages, solve various foam problems, and ensure the smooth progress of production and stable product quality.
