When evaluating the performance of defoamers, a comprehensive evaluation can be conducted from multiple dimensions. By adding a certain amount of defoamer to the foaming solution, observe and record the time when foam disappears. The shorter the time, the faster the defoaming speed and the better the defoaming performance. Add

approximately 0.1% to 0.5% defoamer to the foaming solution and observe the defoaming rate. Under the same dosage, different types of defoamers have different defoaming speeds, and the faster the speed, the better the performance.

Defoaming rate represents the proportion of defoamer to eliminate foam in a specific time. Although direct quantification of defoaming rate may require specific experimental equipment and methods, it can be roughly evaluated by observing the degree of foam reduction.

Half life is an important parameter for measuring the persistence of defoamers, representing the time required to halve the defoaming effect. The longer the half-life, the better the persistence of the defoamer, which can maintain effective defoaming effect for a longer period of time.

Foam inhibition performance refers to the ability of defoamer to inhibit the production of foam. Add a certain amount of foaming liquid into the measuring cylinder and cycle the foaming. After adding the defoamer, record the time when the foam disappears and then bubbles again to the required scale. This time is the foam inhibition time.

The longer the foam suppression time, the better the foam suppression performance. In the actual production process, observe the formation of foam after the use of defoamer, as well as the stability, height, duration and other parameters of foam.

In summary, judging the performance of defoamers requires comprehensive consideration and evaluation from multiple aspects such as defoaming performance and foam inhibition performance. In practical applications, it is also necessary to choose the appropriate type and dosage of defoamer according to specific process conditions and

requirements.