Achieving optimal paper production with Alkyl Ketene Dimer (AKD) sizing requires careful attention to several key factors. NINGBO INNO PHARMCHEM CO.,LTD. guides paper manufacturers through the essential considerations for maximizing the benefits of AKD in their processes.

1. pH Level: AKD sizing is most effective in neutral to slightly alkaline conditions, typically between pH 7 and 9. Maintaining this pH range is crucial for the efficient reaction of AKD with cellulose fibers and for achieving consistent sizing results. Fluctuations in pH can significantly impact the performance of the sizing agent.

2. AKD Emulsion Stability: AKD is a waxy solid at room temperature and must be emulsified in water for application. The stability of this emulsion is critical. An unstable emulsion, characterized by particle agglomeration or separation, can lead to uneven sizing and reduced efficiency. Proper preparation techniques, appropriate emulsifiers, and controlled storage conditions are vital to ensure a stable and effective AKD emulsion.

3. Curing Process: The sizing effect of AKD is not instantaneous; it develops as the paper is dried and heated. This curing process, where AKD reacts with cellulose, is temperature and time-dependent. Higher temperatures in the drying section of the paper machine accelerate the curing, leading to better and more permanent sizing. Ensuring adequate drying temperatures and residence times is key to achieving the full potential of AKD sizing.

4. Dosage and Timing of Addition: The amount of AKD applied and when it is added to the pulp stream are critical. Overdosing can lead to issues like excessive sizing or impact on other paper properties, while underdosing will result in inadequate water resistance. The optimal dosage is determined by the specific paper grade and desired properties. The point of addition should ensure sufficient time for retention and distribution on the fibers before sheet formation.

5. Retention Aids: To maximize the efficiency of AKD, retention aids may be employed. These chemicals help to fix the AKD-treated fibers and particles onto the forming paper web, preventing them from being lost in the water circulation system. The selection and dosage of retention aids should be optimized in conjunction with the AKD application.

6. Fiber Type and Process Water: The nature of the pulp fibers and the characteristics of the process water can also influence AKD performance. Different fiber types may have varying affinities for AKD, and water hardness or ionic content can affect emulsion stability. Careful consideration of these factors can help tailor the AKD sizing process for specific mill conditions.

NINGBO INNO PHARMCHEM CO.,LTD. provides high-quality AKD products and technical support to help paper mills navigate these factors successfully. By mastering these key elements of AKD sizing, manufacturers can consistently produce paper that meets the highest standards of quality and performance.