Discuss Process model, Physical model and Procedural control model of S88 batch process

 In the context of the S88 (ISA-88) batch process control standard, three key models are used to describe and define the components and behavior of a batch process: the Process Model, Physical Model, and Procedural Control Model.

1. Process Model: The Process Model represents the overall structure and hierarchy of the batch process. It defines the various units and their relationships within the process. The Process Model provides a high-level view of the process, identifying the major process equipment and the flow of materials and information between them. It helps in understanding the overall process flow and the interactions between different units.

2. Physical Model: The Physical Model represents the physical components of the batch process, including the equipment, devices, and instruments involved. It defines the physical attributes and characteristics of each unit, such as its physical location, connections, and properties. The Physical Model provides a detailed representation of the hardware and infrastructure required to execute the batch process. It ensures that the necessary physical resources are available and properly configured to carry out the desired operations.

3. Procedural Control Model: The Procedural Control Model represents the control strategies and logic required to operate the batch process. It defines the sequence of operations, setpoints, and actions necessary to achieve the desired process outcomes. The Procedural Control Model includes the control modules and their interconnections, which implement the control functions at various levels of the process hierarchy. It provides a structured approach to designing the control strategies, allowing for easy modification and reuse of control modules across different batches.

The three models are interconnected and work together to enable effective batch process control. The Process Model provides the context and overall structure of the process, the Physical Model ensures the availability of the required physical resources, and the Procedural Control Model defines the control strategies and logic to carry out the operations.

By employing these models, the S88 standard facilitates a modular and systematic approach to batch process design and control. It allows for the separation of process-specific information from the control system, enabling greater flexibility, reusability, and maintainability. The models serve as a foundation for efficient batch execution, optimization, and troubleshooting, leading to improved process performance and product quality.