Recipe controlled batch processes are one of the focal points in many areas of the process industry and especially this type of process show a particular complexity. Special requirements are to be met by an automation solution when it comes to securely master the efficient simultaneous processing of a large number of production orders for different products in one plant. Here Plant Batch iT  provides the ideal platform

• Current standards like ISA 88 are implemented consequently but at the same time focussed on real-world requirements.
• The process control system Plant Direct iT is completely integrated covering the ISA 88 structural level closest to the process.
• Order- and batch-related production data acquisition is provided by Plant Acquis iT that is also integral part of Plant Batch iT

Being tooth pitched directly with Plant iT material provides transaction-accurate material tracking in real time.

ISA 88 – too much and not enough

Plant Batch iT provides an implementation  of the procedural , physical and recipe model, but also of the ressource status handling according to ISA 88, combined with additional functionality that are a result of our experiences in automating recipe-controlled processes.
Beside the availability of a production line as structural element for a plant, within the physical model there are three different types of units defined and implemented.

The use of

• Storage Units,
• Processing Units and
• Transfer Units

takes consideration of the fact that pure storage locations, "real" units and pure transport equipment (e.g. piping) are to be treated significantly different in the context of a batch system. The strict interpretation of the ISA 88 recipe model would cause unnecessary administrative workload in many applications without gaining a significant benefit in process transparency. For this reason Plant Batch iT provides simplification of the recipe model in several levels depending on the application requirements. The partial or complete disaggregation of the unit as a strucutral element allows a simplification of the master recipes regarding their structure. By means of a recipe model special to Plant Batch iT an additional simplification can be achieved by reducing the number of recipes to be managed.

Production based on bills of material

While consequently keeping up the separation of master recipe and control recipe Plant Batch iT is able to process so called process descriptions. Formally seen they are master recipes which contain variables instead of finally defined product-related parameters. The creation of a control recipe takes place during runtime by order-related, dynamic combination of a process description with a bill of material that can also contain a complex set of recipe parameters beside the list of ingredients and quantities. This extended recipe model has two advantages:

• When producing a large number of different products following the same process there only a small number of process descriptions needed, i.e. the workload for managing master reicpes is lowered significantly.
• The possibility of processing production orders based on bills of material provides an optimal basis for the cooperation of Plant Batch iT with many ERP systems, because these systems in most cases "think" in bills of materials.

Process control system included

The seamless integration of the process control system Plant Direct iT in the batch system allows for a maximum of flexibility during running production and at the same time full process transparency from the production order right down to the single actor or sensor, which is currently used for processing the order. Thus the production staff can use the full range of the plant potential, because intervention in the production
is possible on every level any time and are safe-guarded by Plant Batch iT. Furthermore the operator can carry out extensive diagnostics and corrections independent from the technical staff.

Order management and processing

The central instrument for controlling and monitoring the production is the order management of Plant Batch iT that provides three levels of detail to the production staff:

• Order list
• Batch matrix
• Batch list

The order list provides an overview of all dispatched orders and – if this posibility was used – the single batches of the order. All relevant order data as well as the current status are here visualized online. Dispatching of orders can be done manually via the operator interface of Plant Batch iT but alo via standard interface of Plant iT by a superordinated system (e.g. SAP-PP).
The batch matrix shows a tabular online status overview of all batches of active orders which are currently being processed, right down to the operation. The batch list provides a detailed overview of one single batch being processed and direct access to the operation-internal functionality, represented by an object of the class Phase Controller. Intervention on order and batch level (e.g. Start, Halt, Continue, Abort) are possible from  any of the described levels. The batch list allows additional modification of all recipe and order parameters of operations which have not been started by the system.

Electronic Batch Recording

Plant Batch iT records all order and batch relevant data and summarizes them within an Electronic Batch Record (EBR).
The batch record contains

• all relevant header data of the production order to which the particular batch belongs and
• a detailed image of all data like they would have been displayed in the batch list in the moment the batch was completed or aborted.

As an option the batch record contains additionally:

• Step records of the Phase Controller objects (operation-internal functionality)
• Graphical view of order-related production data and
• Order-related message lists.

The batch records are available online for a selectable period of time, but can also be exported and archived.

Material – the most important resource

Ingredients, intermediate and finished products are in actual fact the core resources of any process. In relation to batch processes their transaction accurate tracking and precise allocation to single orders and batches are of special importance.
For meeting this requirement, Plant Batch iT is inseparably tooth pitched with the process-orientated material management Plant iT material. The creation of booking records necessary for inventory management as well as tracking & tracing is carried out automatically by Plant Batch iT to
the largest possible extent and with strict allocation to order and batch ID. For enabling a consistent and comfortable tracking & tracing, the evaluations made within Plant iT material allow direct branching off to the electronic batch records of Plant Batch iT and vice versa.