How to use papermaking defoamer XS-02, polyester ether defoamer? What is the recommended dosage?

Papermaking defoamer XS-02 is generally used by continuous drip addition or dilution before addition. The recommended dosage is 0.01% to 0.1% of the total system (i.e., 100~1000 ppm). The specific dosage needs to be determined through on-site small-scale tests.

Detailed Explanation

Papermaking defoamer XS-02 (polyester ether defoamer) is a non-ionic self-emulsifying defoamer, appearing as a white to light yellow viscous liquid with good self-emulsifying dispersion performance in water. Due to its high viscosity, to ensure rapid and uniform dispersion in the system and fully exert its defoaming and foam-inhibiting effects, it is generally recommended to use the method of continuous addition after online dilution, avoiding one-time direct dumping of large amounts that may cause local high concentration or uneven dispersion.

According to information from the Guoli Chemical product database, this product can achieve ideal foam control effects at very low dosage, significantly reducing usage costs without interfering with subsequent processes such as sizing and coating. The specific usage method and addition point need to be designed according to the application section: In the pulp black liquor section, it is recommended to add at the black liquor tank inlet or the circulation pump inlet; in the paper machine white water circulation system, it is recommended to add at the white water tank or the stock pump inlet; in the coating process, it can be added during the slow stirring stage of the coating preparation tank.

The product database currently has no precise universal dosage value because the optimal dosage of defoamer is affected by various factors such as system temperature, pH value, stirring intensity, foam generation rate, and medium composition. The following recommended dosages are based on common industry practical experience:

Application Recommendations

Usage Key Points

• Pre-treatment dilution: Pre-dilute the undiluted product with water at a ratio of 1:5~1:10 to form an emulsion, which can significantly improve dispersion speed and defoaming efficiency. It is recommended to prepare and use immediately.
• Addition point: Choose a location upstream of the foam generation point or where fluid turbulence is high (such as pump inlet, pipe bends), utilizing fluid shear force to help disperse the defoamer.
• Addition method: It is recommended to use a metering pump for continuous drip addition, which provides more stable effects and longer foam inhibition time compared to intermittent batch addition.
• Determining optimal dosage: For first-time use, it is recommended to start with a gradient test from low concentrations (such as 50 ppm, 100 ppm, 200 ppm) to find the minimum dosage that just controls foam overflow as the economical usage amount.

Precautions

• Product storage temperature is 5~35°C. If stratification occurs after long-term storage, stir evenly before use; product performance will not be affected.
• Diluted solution should be used within 24 hours to avoid stratification or microbial growth due to prolonged standing.
• Avoid direct mixing with strong oxidizers. Its non-ionic nature provides good compatibility with anionic and cationic additives, without causing precipitation or side reactions.
• Excessive addition may reduce paper sizing degree or cause oil spots; dosage should be strictly controlled to avoid exceeding the recommended range significantly.
• Wear protective gloves and goggles during operation to avoid prolonged direct skin contact. Although the product is low-toxicity and non-irritating, it is still recommended to maintain good ventilation and follow basic chemical handling procedures.