Foams antifoaming agents

When undesirable foaming of a solution cannot be reduced sufficiently by replacing the surfactant with a lower foaming one, or when the foam is caused partially or entirely by nonsurfactant components of the solution, then antifoaming agents are used to reduce the foam. Antifoaming agents act in various ways ... 

Antifoaming Agents. Foaming is a frequent problem in food manufacturing operations causing production inefficiencies. 

Quahty control testing of siUcones utilizes a combination of physical and chemical measurements to ensure satisfactory product performance and processibihty. Eor example, in addition to the usual physical properties of cured elastomers, the plasticity of heat-cured mbber and the extmsion rate of TVR elastomers under standard conditions are important to the customer. Where the siUcone appHcation involves surface activity, a use test is frequently the only rehable indicator of performance. Eor example, the performance of an antifoaming agent can be tested by measuring the foam reduction when the sihcone emulsion is added to an agitated standard detergent solution. The product data sheets and technical bulletins from commercial siUcone producers can be consulted for more information. 

Entschaumer, m. skinuner, scummer, foam remover antifoam agent, entscheiden, v.t. decide. — entscheidendi p.a. decisive flnal. 

If these trays are used in systems with exceedingly high foaming tendencies, tray action may be impaired to the extent of improper performance. In such cases, the foaming tendency should be examined experimentally. Antifoam agents have proven quite helpful in some problem cases using these trays. 

In addition, even where foaming is not a specific problem in a boiler, carryover may occur, especially in lower pressure boilers with very high TDS (i.e., over 10,000 to 15,000 ppm TDS) because of the collapse of surface bubbles. This leads to BW aerosol generation and entrainment of the spray in steam. Under these circumstances, antifoam agents such as polyamides are useful in preventing these entrainment problems. Furthermore, the antifoaming action of polyamides is often enhanced by protective colloid materials such as tannins, and consequently, formulations containing polyamide emulsions in an alkaline tannin base are available. 

Although glycol-water formulations are not prone to foaming, mechanical and chemical factors may cause foaming in the system. The use of corrosion inhibitors and the presence of contaminants may enhance the tendency to form foams. For these reasons, antifoaming agents, such as silicones, polyglycols, or oils, are sometimes added. 

Other minor uses of detergent alcohols include lacquer solvent, synthetic lubricants (which need lots of different kinds of slippery long-chain molecules), antifoaming agents, herbicides, lube oil additives, and stabilizers for fire extinguisher foams. ... 

Antifoam Agent An additive, usually silicone- or polyglycol-based, used to reduce foaming in petroleum products. 

One of the defects of the synthetic material is its copious foaming power, which generally must be corrected by the use of antifoam agents. The foaming problem is especially important in soft water. 

Antifoaming agent A chemical that is added to a liquid mix to prevent formation of foam, or added to the foam itself to break a foam already formed. 

Foam Control. Fermentations tend to froth because metabolites have surfactant properties. Prevention commonly is by addition of antifoam agents such as oils, heavy alcohols, fatty acids, or silicones. High-speed rotating impellers destroy bubbles by direct impact and by throwing them against the wall of the vessel. 

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