Application of silicone defoamers
Source:iotachem.com
PostTime:2024-07-26 15:29:50
1. Textile printing and dyeing
Sizing process: water-emulsion type silicone defoamer, such as silicone polyether, added in the sizing tank at a dosage of 0.2-0.25 g/L
Chemical fiber oil: Add 0.02-0.04% water emulsion type defoamer to the chemical fiber oil. The chemical fiber oil formula should contain silicone oil.
Desizing and refining: Use polyether silicone.
Bleach : Strong acidity, silicone defoaming agent.
Dyeing: Silicone emulsion defoamer. For jet dyeing, it is best to use polyether silicone, which has high-temperature defoaming, low-temperature water solubility, and does not stain fabrics.
2. Petrochemical Industry
Drilling : Ethyl silicone oil (or methyl silicone oil emulsion) is used as mud additive.
Oil production: oil and gas separation, defoaming rod. The melting point is 2.8-13.9℃ higher than the wellhead foam temperature.
Natural gasoline absorption: Use gasoline to prepare a 2% solution of dimethyl silicone oil.
Oil and gas separation and demulsification:
A. Oil and gas separation, adding 0.025-0.0065 mg/Kg to crude oil can improve production capacity;
B. Demulsification: The crude oil for oil and gas separation is generally a micro W/O type emulsion. Adding about 0.2 mg/Kg of a suitable defoaming agent can achieve the effect of demulsification and defoaming.
Refining: Add defoaming agent during vacuum distillation to improve the color of the fraction and widen the fraction range. Diesel solution with silicone oil is often used.
For high energy fuel (internal combustion, jet, aviation fuel), cyanoalkyl polysiloxane is dispersed in high flash point kerosene and then added to the high energy fuel as a high efficiency defoaming agent.
Asphalt, residual oil: Add silicone oil in an amount of 0.2×10－6～2.0×10－6
Delayed coking, decoking, descaling: reference amount of defoaming agent added: 0.05～100×10－6
Defoaming drilling fluid: high viscosity sulfonate metal salt (calcium petroleum sulfonate: sodium sulfonated asphalt = 1:1), the amount of siloxane added is about 100~400×10-6 or 5~15mg/Kg, and the ratio of sulfonate: siloxane is preferably close to 1:1.
Lubricating oil: such as internal combustion engine, automotive lubricant, metalworking fluid, compressor oil, etc., when silicone oil is added for defoaming, it has the following advantages:
A. It is difficult to dissolve in lubricating oil and is in a dispersed state, which is conducive to adsorption on the bubble film to break the bubble;
B. It has an alkyl group similar to mineral oil, which can squeeze into the bubble membrane and weaken the molecular attraction;
C. Low surface tension, good penetration, when adsorbed on the surface of the bubble film, the local surface tension is reduced, and the bubble is broken due to the uneven surface tension of the bubble film. For heavy oil, use low viscosity silicone oil, and the addition amount is 1~10×10-6. In addition, alkyl polyacrylate is also better, with good gas release. Branched amine is added to crude gasoline, naphtha, and then added to lubricating oil, which can also be used as a defoamer, with an addition amount of 0.05~1%. This defoamer can be added to metal cutting fluid.
