Abstract: As a solid-liquid separation equipment, the washing section of the rotary pressure filter directly affects product purity and production energy consumption, making it a critical link that constrains the efficient and low-energy operation of the equipment. Conventional washing section design overlooks the differences in cake washing efficiency among individual washing zones, resulting in low washing efficiency, high washing liquor consumption and uneven product quality. This problem is particularly prominent in large-scale plants such as purified terephthalic acid (PTA) plants. Considering the continuous operation characteristics of the rotary pressure filter, this paper systematically establishes a mathematical model of the washing process. A washing zone theory based on the rotary drum's rotational characteristics is proposed. Furthermore, an engineering optimization method for washing zones is constructed, which integrates multiple factors including process parameters, equipment configuration and operating conditions. This study can provide theoretical basis and technical reference for the design and operation optimization of washing sections in similar equipment.

Key words: rotary pressure filter, washing model, washing zones, PTA plant