跳至主要内容

Defoamer Test Method

Defoamer testing methods are divided into dynamic defoaming and static defoaming tests. If your foaming environment is different, the recommended test methods are different. There are three main types of foam experiments to characterize the activity of defoamers. Persistence. As we have different experimental conditions in different laboratories and the experiments used in our research to obtain results from existing literature, we will introduce these experiments below. Other methods are sometimes used depending on the particular application.

1．Ross-Miles Foam Tester  

Features: Tested for strong foaming environments.
This experiment is widely used for characterization
       (1) Foaming of surfactant solution
       (2) Research and application of foam stability in the presence of defoamer
In the foaming system, the defoaming performance test was carried out by circulating bubbling by a Ross-Miles foam meter. In a 2000 mL measuring cylinder, a certain amount of foaming liquid was added to adjust the flow rate, and foaming was performed through the foaming liquid. When the foam to be produced rises to the 2000 mL mark, a quantitative defoamer is added, and the foam elimination time is recorded. When the foam disappears, the circulation is continued to be bubbled and the bubble inhibition time of 2000 mL is recorded.

2．Air drum test

Features: Tested for strong foaming environments.
The foaming liquid and the defoaming agent were added to a 500 ml measuring cylinder, constant to a set temperature, and air was bubbled into the set flow rate, and the volume of the bubble volume (including the sum of the volume of the foam and the medium) was recorded as a function of time T.

3．Shake flask test

Features: Quickly identify the quality of defoamers.
The measuring cylinder is used to measure a certain amount of foaming medium, and the temperature is adjusted to the specified temperature. The antifoaming agent sample is added, the stopper is covered, the measuring cylinder is shaken up and down several times at a certain frequency and swing, and the cylinder is allowed to stand and the timing is started, and the foam is discarded. The time taken for the liquid surface to appear, that is the defoaming time of the shake flask.

learn more details, please forward to : https://www.ywlchemical.com/about-us/
标签：

评论

发表评论

此博客中的热门博文

How do we assess antifoam efficiency ?

How do we assess antifoam efficiency ? Quality of an antifoam is given by two main characteristics : • Knockdown ability or shock effect :Meaning the speed to destroy an existing foam. • Persistence or durability : Meaning the efficiency over time.   These two parameters can be assessed by several tests. The main test is the bubbling method. A graduated column with a glass frit in the bottom is required. Foaming water is poured in the column and air at constant flowrate is introduced through the glass frit in the column. Foam is generated by the air and starts to travel up the column. At a determined level of foam, antifoam is injected. By this method several antifoaming agents can be tested. A graph reporting foam height vs time is very helpful to establish the knockdown ability and the persistence for each product. The selected antifoam is the product with the best compromise between shock effect and durability       Environmental performance   Silicone antifo...
1 条评论
阅读全文

What is a defoamer / deaerator’s purpose in the system?

What is a defoamer / deaerator’s purpose in the system? Defoamers prevent formation of foam during manufacture and application of coatings and printing inks. Foam that is already formed is destroyed and air occlusions are prevented. Deaerators prevent development of air occlusions and pinholes. Why use a defoamer? The occurrence of foam is considered an undesirable but unavoidable phenomenon in coatings and printing inks. The formation of foam interrupts production processes, reduces the effective volumes in the production plant, and leads to unnecessary down time. Foam also interferes with the application process. In printing, foam can cause the ink reservoirs to overflow and can impair ink transfer from the printing cylinder to the substrate. Dried foam leaves surface defects in the paint film. To prevent foam and destroy any foam present, defoamers must be added to the formulation. defoamer vs. deaerator? To eliminate macro-foam on the surface, to prevent air occlusions, and...
发表评论
阅读全文