8.3 Batch Control Description, Terminology, and Standard S88

B. A. JENSEN (1995, 2004)

FEATURE SUMMARY Forum (EBF) and Japanese Batch Forum (JBF), which facilitate the same agenda. Batch processing and automation are discussed in this section Batch automation and batch control is unique depending both from a management point of view and from the per- upon the perspective used to describe it. Unlike continuous spective of the types of software structures required to imple- processes, a batch process has a finite beginning, middle, and ment it. Other sections in this chapter also deal with the end. Though it has been argued that continuous processes subject of batch control. Section 8.4 concentrates on batch can be thought of as batch processes with very long batch processes and their automation, while Sections 8.8 to 8.10 cycle times, the uniqueness of batch control has to do with are devoted to the automation of chemical batch reactors. what procedure is performed, what formulations are used, In 1988, the Instrumentation, Systems and Automation and on what type of equipment. Society (ISA) formed a standards committee to provide guide- Batch processes are event-driven processes that vary with lines for the design and specifications of batch control systems time. Charging, heating, reacting, agitating, cooling, and dis- as used in the process industries. Building upon previous work charging are examples of sequential events in time requiring of the German NAMUR (Normenarbeits-gemeinschaft fur corresponding control actions. In the design of a batch control Mess und Regeltechnik in der Chemischen Industrie) and the system, time-based process conditions and transition phe- Purdue Workshop TC-4 committee, the first part of the mul- nomena must be handled. Attention to abnormal events and tipart standard (“Models and Terminology”) defined terminol- the interface to the operator may actually take more of the ogy specific to batch control systems to facilitate understand- design process than that of the actual automation. ing between manufacturers and users.1 It also defined a Batch processing can be viewed through three perspec- standard batch control architecture that outlined a hierarchical tives. One is from a process point of view. The second is an structure relating control equipment and data communications equipment view by which products are processed. The third needed for the physical areas involved in batch control and a is a product-based view, or recipe-based view. To that end, functional model that showed the relationships between the the discussion will first begin on the process point of view. control activities of recipe management, production scheduling, information management, batch management, unit super- BATCH PROCESS CLASSIFICATION vision, and process control (sequential and regulatory control) required in batch control. This evolved into an international 2 A batch processing model must consider that a batch can standard: IEC 61512-1. As such, the other sections are also have more than one end product and that production is pos- turning onto IEC standards including “Part 2: Data Structures sible in various plants or plant areas. Thus, batch processes and Guidelines for Languages,”3 IEC 61512-2 standard in 4 can be classified according to either the number of products 2003. “Part 3: General and Site Recipe Models and Repre- made or the physical structure of the process. sentation” was approved by ISA in March 2003,5 while 6 “Part 4: Production Records,” is expected shortly. Recipe Point of View In addition, a nonprofit, professional organization called the World Batch Forum (WBF) was established in 1994 to A recipe is a batch entity that contains “the necessary set of promote the exchange of information related to the manage- information that uniquely defines the production requirement, operation, and automation of batch process manufac- ments for a specific product.”1 That includes the header (pur- turing. This association of end users, vendors, consultants, pose, source and recipe version product identification, cre- and academics hosts an annual conference with formal pre- ator, and issue date) the procedure (the strategy and set of sentations and technical papers dedicated to advance batch instructions and action needed to carry out the production of processing knowledge and technology, with a strict, noncom- a batch), formula (process input values, process parameter mercial agenda. Other forums include the European Batch variables, and process output data), equipment requirements,

1528

© 2006 by Béla Lipták 8.3 Batch Control Description, Terminology, and Standard S88 1529 and miscellaneous information, such as material safety data Table 8.3a lists a variety of factors that can be considered sheets (MSDS) and any other material that may be related to in distinguishing batch processes. the batch. Batch processes can be classified according to the number of chemicals, substances, or items produced, as follows: single procedure/single formula, single procedure/multiple formula, TABLE 8.3a or multiple procedure/multiple formula. A single-procedure/ Variations in Batch Processes and Their Features single-formula batch process produces the same product in each Features Choices batch. The same operations are performed in the same sequence, using the same percentages of the raw materials, Types of recipes Single procedure/single formula though the batch sizes may change. Many of these types of Single procedure/multiple formula plants can be converted to continuous processes. The single- Multiple procedure/multiple formula procedure/multiple-formula batch process produces different Topology of plant Numbers of stages grades of products that are similar but differ in formula quan- Series/parallel/networked tities. The same operations are performed in each batch, but the Interconnections: fixed or flexible connections quantity of raw materials or processing conditions are varied. Shared or exclusive use resources allocations The procedure is the same but the formulas are changed. Mul- Type of equipment Single-purpose tiple-procedure/multiple-formula batch processes produce Multipurpose products by utilizing different methods of production or control. Movement of batches Fixed paths/varying paths from batch to batch The procedures performed, the amounts of raw materials used, predefined in a recipe the processing conditions encountered, and the equipment used Dynamic unit assignments coupled with may vary with each batch. This is the most difficult of the three continuous processes batch-type processes to automate. Automatic reblending/rework Control activity levels Safety interlocking Equipment Point of View Basic control Unit supervision Batch facilities can also be characterized according to the Batch management physical structure of the process facility. Three basic types of Production planning and scheduling batch structures are series (single-stream) structures, parallel Information management (multistream) structures, and networked structures. A series Recipe management structure is a group of batch equipment through which a batch Sequence Number of control actions, inputs, and outputs passes sequentially. It could be a single batch unit, such as a requirements are small reactor, or several processing units in sequence. In the parallel Number of independent sequences and parallel actions are small structure several batches can be undergoing the same (or different) operations at one time. A hybrid of the two structures Amount of operator As part of the normal execution includes is a series/parallel batch process, also known as a networked- intervention verification of required manual actions Overriding the recipe in case of abnormal type structure whereby the batch can pass through any equip- events with return to automatic execution ment type. This requires the highest degree of sophistication in control equipment to achieve effective batch control. Exception handling Permissives for advancing through unit procedures procedure Product Point of View Interlocks continuously checked, system suspends or is held on detection of The product is the overall objective of any batch process. This abnormality view takes into account repeatability and quality of the batches Interlocks independent of operations and produced. It is information intensive. It is concerned with batch phases; same interlocks throughout batch; no and unit recipe cycle times, cycle time frequency, batch and jumping to other phases Interlocks cause jump to a safe state; interlocks unit recipe performance ratings, product quality, and other per- are control-step independent formance-based metrics. Questions are answered, such as, Interlocks are a function of operations and When was batch B-4290 made? What equipment was used? phases; both shutdowns and jumps involved; What products were in progress at 14:00, 2 May 2004? How may be a number of abnormal transitions and was the product made in 2002? How long does it usually take states to make this product? Which reactor typically makes this prod- Requirements for Receiving and storing information on uct the quickest? What other batches were in progress when B- batch data collection individual batches 4290 was running? What products have the greatest variability Producing output information on one or more in their production? A fully developed automation system with batches a historical recipe-based manufacturing execution system is Producing batch reports required to support this view. Maintaining a batch history archive

BATCH AUTOMATION locking. The following paragraphs describe the control activities as they pertain to batch processes, from the lowest level on up. Automation of batch production is composed of three func- Batch automation is planned from top down and imple- tional levels: mented from the bottom up.7

1. Batch planning: The sequence of production is Process/Product Management planned and scheduled taking into account the available resources, including raw materials, personnel, and Process/product management is the highest level of control equipment. activity. This is where corporate planning for the business is 2. Batch control: Production ﬂows and production steps made and is linked to the various operating units. Activities are described. Recipes are processed and executed in like material and resource planning (MRP), inventory plan- this level. ning, and accounting take place. 3. Real-time monitoring and control: Basic equipment Process/product management is an activity that accepts control is performed at this level. This classical pro- inputs, such as customer orders, and based upon a manufac- cess automation includes safety interlocking input/out- turing strategy develops a production plan. The production put processing, and routine sequential, regulatory, and plan can cover such topics as: discrete control. What is to be produced? The control activities of an entire batch control system are How much is to be produced? shown in a hierarchical manner from the sensors and elements When is it needed? to the business planning level in Table 8.3b. In many organi- Where is it to be produced? zations the lines between the levels may be quite blurred. How is it to be packaged? Additionally, the levels may be compressing though the functions and activities are certainly valid. The output of the production plan becomes an input to Batch planning activities involve process/product manage- the production schedule of the individual plant. Process/prod- ment, production/batch management and production planning uct management entails a broad range of corporate planning and scheduling, batch control activities involve batch management and unit supervision, and basic equipment control activi- and provides the basis for management’s relationship with ties involving sequential/regulatory/discrete control of physical its operating units. control devices, such as sensors and actuators, and safety inter- Production Management

Production management is made up of three control activities: recipe management, production scheduling, and batch TABLE 8.3b history management. Control Activity Model Level Function Activity Recipe Management A recipe is the complete set of data Planning Process/product Production planning, inventory and operations that define the control requirements of a par- management planning, general recipe ticular type or grade of product. A recipe is composed of the management, etc. following types of information: (1) header, (2) equipment Production Recipe management, requirements, (3) formula, and (4) procedure. Headers pro- management production scheduling, batch vide information about the source and version of the recipes, history management, etc. such as recipe and product identification, author, issue, and Batch control Batch management Recipe generation/selection, date and any other pertinent batch information such as MSDS batch execution supervision, or hazard or toxicity issues specific to the product or pro- unit activities coordination, cessing activities and the like. Equipment requirements spec- log and report generation, etc. ify the type and size of equipment needed, such as glass Unit supervision Unit allocation management, lining required and 20,000-liter vessel required. Formulas are unit coordination, etc. sets of parameters, such as types and quantities of ingredients, Monitoring and Process control Sequential/regulatory/discrete durations, and process condition set points, that distinguish control control: device, loop, and the products defined by procedures. Procedures define and equipment module control, order the actions to be performed and the associated control predictive control, model- requirements necessary for making a class of products in the based control, process batch process. interlocking, etc. The procedure defines the generic strategy for producing Safety interlocking — a batch product. A procedure is made up of unit procedures.

Drawings Includes Product-speciﬁc General recipe processing information Procedure

May be Consists of an transformed into ordered set of Includes Site-speciﬁc Unit Site recipe procedure information

Consists of an ordered set of May be transformed into Operation Includes Process cell-speciﬁc Master recipe information

Consists of an ordered set of Is the Phase basis for Batch ID, batch size, Includes in-process, operator- Control recipe and/or system- FIG. 8.3c generated information Procedure model. FIG. 8.3d Recipe model. Unit procedures are an ordered set of operations that causes a continuous production sequence to occur in a unit. An operation is an ordered set of phases that defines a major the general recipe to a site-specific recipe. Equipment knowl- processing sequence. And operations are made up of phases edge (for example, what vessels and piping are available at that accomplish a process-oriented task. Phases may include the plant) is used to transform this site recipe into a master the control steps or control instructions that execute the base- recipe. This master recipe is used as the basis for a control level control. The relationship is diagrammed in Figure 8.3c.1 recipe when a batch is ready to be produced. The activities The actual executable logic of the control is linked via the involved during recipe management are summarized in recipe information to a particular unit where the unit recipes, Figure 8.3e. operations, or phases are run in the order determined by the recipe. Production Scheduling Schedules serve as guides for pro- In the current generation of control systems, the recipe duction requirements in terms of availability of equipment, management function maintains a set of master recipes for personnel, raw materials, facilities, equipment, and process various products and families of products. Specific information capacity. The schedule generally has many of the following of the batch equipment and units that can run each operation objectives: within the procedure are contained within the control recipe. A master recipe is constructed from the site recipe using the 1. Minimize the processing time formulas, procedures, and equipment-specific information. 2. Minimize the deviation from a master production plan The master recipe is selected and accessed by the batch man- 3. Optimize the production of products within quality agement activity, which converts it to a control recipe. This guidelines control recipe is the batch-specific recipe that is ready to run. 4. Minimize energy costs The hierarchy of recipes is shown in Figure 8.3d.1 5. Minimize the usage of raw materials Utilizing process and product knowledge, a process anal- 6. Minimize rerun ysis is performed and basic phases are determined. These basic phases, along with product knowledge from the labo- Production scheduling accepts inputs such as the produc- ratory chemist, are used to construct the general (corporate- tion plan and based upon a scheduling activity develops a wide) recipe. Plant knowledge (for example, raw material production schedule that typically specifies batches/amounts availability) from the plant site engineer is used to transform to be produced, target trains/lines to be used, time targets,

Process & Process product Basic analysis knowledge phases

Store and manage basic phases

Product Construct knowledge general recipe (chemist)

Store and manage general recipes General recipe System & Plant Construct Construct equipment knowledge site recipe phase logic (raw materials etc) knowledge

Store and manage site recipes Phase Site logic recipe Equipment Construct Store & manage knowledge master recipe phase logic (train conﬁguration)

Create a production Master Store & manage Master Create schedule recipe master recipes recipe control recipe

FIG. 8.3e Recipe activities. product dispositions, and resource constraints. In essence, the ule automatically via some algorithm or manually via user master production schedule answers what to schedule, when intervention. to schedule, and how much to schedule. Schedulers can be implemented via any number of ways. The production schedule further reduces the production Linear programs, expert systems, or other multivariable tech- plan, which was developed in the company management layer niques have been used successfully.8 The scheduler needs to (process/production management) and directly drives the pro- provide a procedure or method for batch sizing and is the duction of individual batches. The responsibility of the pro- logical place where lot or even batch ID assignments are duction scheduler is to develop a detailed time-based plan of made. A production scheduling model is shown in activities to achieve the production targets set by the produc- Figure 8.3f. tion plan. It needs to dynamically allocate a new schedule at As shown by the model, a dynamic scheduler accepts any time. It should be feasible to reallocate or create a sched- user inputs, master recipe information, and updates from

To schedule generation Detailed schedule

Dynamic User schedule inputs

Master recipe scheduling information

From batch mgmt. Batch schedule

FIG. 8.3f Production scheduling model.

© 2006 by Béla Lipták 8.3 Batch Control Description, Terminology, and Standard S88 1533 process management to develop a batch or production sched- 3. Producing batch reports on the basis of output infor- ule. The dynamic scheduler must be able to: mation 4. Maintaining production records and batch history Organize a new schedule at any time archive by supporting data reduction, backup, and Provide for interactive scheduling deletion features Allow for manual intervention Determine the availability of resources Although many data logging and reporting techniques Provide for a method to carry out the schedule for batch processes are similar to those for continuous sys- Provide a procedure or method for the lot sizing along tems, production records have some significant requirements with a means to organize autonomous orders with that may be different. Two needs are batch tracking (some this lot size may use the term lot tracking) and the batch end report. Determine the feasibility of the schedule A batch historian must collect and maintain integrated, identifiable sets of dissimilar data. Batch tracking is the col- Information about times and availability of resources are lection of this data. It is generally event-triggered and typi- key inputs to the scheduler. Because the basic data about cally contains the following related data: the unit operations, master recipes, key times, resources, quantities, priority, and orders and their operations are Continuous process data (flows, temperatures, and required, it seems reasonable to conclude that the dynamic pressures) scheduler is a real-time activity. The dynamic scheduler Event data (operator actions, alarms, notes) requires non-real-time data from production planning and Quality data (lab analysis, inspection notes) recipe management as well as real-time feedback data from Recipe formula data (quantities desired and used, set the batch manager and lower-level control activities. The points, times) dynamic scheduler can contain some kind of optimizing capa- Calculated data (totalizations, material usage, account- bility. Batch management provides the updates of information ing data) to the scheduler in real time and also provides the status of Manual entries with audit trail (location of change, material and equipment. operator of record) The user needs to be advised of the schedule situation Stage, batch, lot identification continuously. Thus, reporting and status information are Time/date stamps on all data important. Information provided to the user can include the control recipe, the lot number, the product being produced, A batch end report may typically include a copy of the the amount being produced, the train/line being used, the master and/or control recipe that was used to make the batch. status of the recipe, the mode of operation, priority, start times, This may not be identical to the original recipe because of and end times. The mode of the lot in the queue determines operator modifications, equipment problems, and so on. Events whether the recipe is to start automatically, semiautomatically, such as alarms, operator instructions, and equipment status or manually. In the manual mode, stepping through the batch changes should also be logged. This log can be designed so sequence is done by the plant operator via specific commands. that it will retain the total operational sequence chronologically In semiautomatic mode, the batch sequence is initiated by the with date and time. A trend chart can also be retained. A recipe operator and requires operator intervention when proceeding expresses the desired approach by which a batch is to be from one phase or operation to another. In the automatic mode, made, while the batch report provides a record of how the once the sequence is initiated, it can be repeated a predeter- batch was actually made. Batch management takes care of mined number of times without any operator intervention. The the recording and collecting of batch end reports, which are mode of the batches in the queue also determines whether any then archived to some other medium. Batch reports are a information in the queue is operator alterable, and whether statutory requirement in some applications (for example, in the control recipe has been bumped or interrupted by another the pharmaceutical industry); however, because the informa- control recipe of higher priority. tion is so valuable, it is being demanded in many other batch applications. A simplified batch history management model Batch History Management Batch history management is is shown in Figure 8.3g. the subject of Part 4 of the ISA S88 standard. It has the Batch history management is an activity that is not bound following main functions: to the actual execution time of the batches and not bound to the equipment on which the batches are produced. It involves 1. Receiving and storing information from other parts of the process of sorting out the production records and batch the overall batch control system on the individual end reports, because even a perfect batch may be undeliver- batches able without batch records. Advances in relational databases 2. Producing output information from single batches, allow the bridging of data between the process control of from several batches, or as an overview of multiple current batches and the histories of previous batches. The batches ability to use standard query language (SQL)-like calls to

Information Request Input

Site information Production planning Schedule update Manage Recipe management and scheduling site Production status information

Batch history Equipment capability Recipe scheduling info Manage batch information

User information & Batch Batch information collection requirements history (history, reports, status)

Process management Batch reports

FIG. 8.3g Batch history management.

access batch history allows new avenues to analyze and report Additionally, the batch management function: batch histories. Other analysis techniques, such as statistical process control and statistical quality control (SPC and SQC), 1. Initiates control recipe execution based on time or can be applied at this level. event 2. Assigns and releases units, and updates their status Batch Management 3. Distributes the parts of the control recipe to unit super- Batch management interfaces with the user, recipe manage- vision ment, production scheduling, unit management, sequential 4. Starts the batch based upon start conditions and the control, and regulatory and discrete control in performing its detailed schedule, whether upon event or time functions of (1) recipe selection, transformation, and editing 5. Regulates the distribution of operation or phases for to manage batches; (2) initiation and supervision of batch execution processes; (3) management of batch resources; and (4) acqui- 6. Reports and time-stamps events for information man- sition and management of batch information. A batch management agement model1 is shown in Figure 8.3h. 7. Allows users to alter normal processing Batch management includes basic functions to managing 8. Maintains batch status information batches by using control recipe information, batch informa- 9. Allows batch to be suspended, removed, and later tion, and equipment information to: recalled

1. Select a master recipe from recipe management and Managing batch resources takes the detail schedule and transform it to a control recipe that can be used to run master/control recipe information and provides for: a batch 2. Assign a batch identification code 1. Dynamically predicting start and end times for batches 3. Time-stamp the control recipe when the batch identi- and operations and tagging batch events fication is entered 2. Maintaining the dynamic schedule of all batches, 4. Verify the information in a control recipe, such as its including their current state completeness and its ability to execute on the selected 3. Dynamically detecting resource requirements and units resource availability 5. Maintain the control recipe until the batch is com- 4. Updating production scheduling with modifications to pleted the schedule

Recipe Production Production management planning and information scheduling management

Master recipe Batch Batch progress Batch and scheduling and process cell process cell information status information information

Manage process cell resources Batch and Process cell resource information information

Collect batch Manage Batch and process cell batches information information

Unit recipes, Commands and commands, and batch status information and status information

Unit supervision

FIG. 8.3h Batch management model.

Additionally, managing batch resources involves: Unit Supervision

1. Receiving the detailed schedule A unit consists of a physical grouping of equipment as well 2. Dynamically detecting conflicts between resources as the unit control functions required to carry out the execu- needed and those that are available tion of a batch. A process unit consists of a group of mechan- 3. Granting “permission” to unit to establish resource ical equipment; each piece performs, in a somewhat indepen- link dent manner, a portion of the chemical process. Examples of 4. Arbitrating multiple requests for resources process units are filters, batch reactors, heat exchangers, and 5. Tracking and maintaining all batches, ready to run, in- distillation columns. Process control involves the actions progress, completed, or aborted required to perform the unit operations. Examples are charging, heating, cooling, agitating, reacting, discharging, and Finally, batch management provides functions to acquire washing. and manage batch information, such as: Unit supervision interfaces with the user, batch management, sequential control, regulatory control, and discrete con- 1. Collecting and reporting batch information by batch, trol in performing its functions of (1) communication with operation, phase, time, or event other units, equipment modules, and control modules; (2) 2. Providing in-progress or complete batch reports acquisition of resources; (3) unit procedure execution; and 3. Archiving and retrieving batch data in batch history (4) exception handling. The unit supervision model as cur- rently defined by the ISA standards committee is shown in A batch report can include recipe data, snapshot process Figure 8.3i. data, or batch data in response to the recipe or on an ad hoc Unit supervision requires certain information from batch basis necessary for documenting the batch. This includes management. The most important information is the recipe operator modifications, historical trends, reports, and other information required to run the unit. This recipe information information that may be available to the operator. contains the executable logic as well as formula information.

Process management

Manage Manage Production information management process cell batches resources

Unit recipes, commands, and Commands and Batch and unit status information status information information

Batch and Manage Unit resource information unit information resources

Acquire and execute Batch Collect batch procedural information and unit elements information

Unit supervision

Commands and Commands and status information status information

Process control Execute Execute non-procedural phases control

FIG. 8.3i Unit supervision model.

Unit supervision performs the unit procedures, operations, the use of the equipment providing the transfers must be and phases in the order they are to be run; performs exception coordinated. logic when some abnormal condition arises during execution; and downloads parameters from the formulas to the control modules. Process Control When more than one processing unit affects the status or use of a resource, the resource is designated as a common Sequential, regulatory, and discrete control functions inter- resource. Common resources almost always exist with par- face directly with elements and actuators to cause changes allel and series/parallel batch process structures. A common in the process. Discrete control is concerned with maintaining resource may either be required exclusively or can be shared. the process states at a target value chosen from a set of known Unit supervision coordinates with other units to account for stable states. Regulatory control serves to maintain the mea- exclusive-use and shared-use resources. surements of a process as close as possible to their respective Exclusive-use resources can be used by only one unit at set point values during all events, including set point changes a time. This means that some mechanism must be in place and disturbances. Sequential control sequences the process to prevent more than one batch from trying to use the resource through a series of distinct states as a function of time. at the same time. Also, the batch scheduling system must These types of control functions are implemented using take this exclusive resource into consideration. Another prob- control modules and equipment modules. A control module lem is associated with distribution of risk in control systems. device is an item of process equipment that is operated as a If a controller module containing the exclusive-use resource single entity and that may have multiple states or values. fails with no backup, all units utilizing the resource are Discrete states are initiated (using hardware and software) to affected. Shared-use resources are associated with units that control discrete devices such as solenoid valves, pumps, and can simultaneously use the common resource. A unit should agitators. A control module loop is a combination of elements not be able to deactivate the resource while other units are and control functions that is so arranged that the signals pass using it, and the capacity of the resource should not be between elements for the purpose of measurement or control exceeded by multiple users. of the process variable. A proportional, integral, derivative The engineering of the equipment into units greatly (PID) control algorithm is a common control loop function. affects how shared and exclusive resources are handled, An example of equipment module control is the sequential which translates into the overall modularity of the batch control of dehydrator bed control valves in order to put one control. As a batch processes through one unit to the next, bed on-line while the other bed is being regenerated according

© 2006 by Béla Lipták 8.3 Batch Control Description, Terminology, and Standard S88 1537 to a time schedule. Most of today’s process control systems 1. Charge times: Ingredients must be metered accurately utilize function blocks as the tools to describe and implement and be added to the mixers or reactors as fast as pos- control modules. sible. Dribble charging and other anticipatory methods Process interlocking and advanced control, in the forms are used to accurately charge the correct amount of an of feedforward, predictive, or model-based control, are addi- ingredient. tional control functions that reside at this level and serve to 2. Reaction times: Good temperature control and accu- achieve a higher level of automation to obtain additional rate pressure detection are essential in order to produce benefits. consistent reactions batch after batch. Liquid chro- As opposed to continuous processing, additional control matographs measuring molecular weight distributions algorithms and control methodology are normally used in and many other analyzers have been used to determine batch processing. Functions such as time-based PID (heat the end of the batch reaction. soak ramps), charging algorithms, sequencers, and timers are 3. Dump time: Reactor contents are emptied. Level often required. Techniques such as enabling/disabling control devices or NMR devices have been used here to deter- functions based upon a phase state, enabling/disabling alarms mine when the batch has been dumped completely. on devices and loops, and employing antireset windup pro- 4. Turnaround time: After a batch is dumped, the time until tection on PI or PID loops are commonly used. Batch pro- the next batch can be charged should be minimized. cesses tend to be device-oriented, while continuous processes are predominantly loop-oriented. Benefits of automation acquired through reduced utility costs can be achieved by minimizing heating medium usage Safety Interlocking and minimizing cooling medium usage. Benefits of automation acquired through higher product quality are much more Safety interlocks ensure the safety of operating personnel, difficult to define. They would normally translate to higher protect the plant equipment, and protect the environment. customer satisfaction and less reject material. These benefits These types of interlocks are initiated by equipment malfunc- can be achieved by achieving tighter control of the batch tion and usually cause shutdown. Often, a separate system is reactors and higher accuracy and consistency in charging the used in implementing the safety interlocks. This system raw materials. includes the necessary redundancy and fault tolerance, and Once the architecture of the plant is known, the control is independent from the other control functions. An example strategies can be planned. An example of a batch plant is of a safety interlock is the stopping of a centrifugal compres- shown in Figure 8.3j. sor if its gear oil pump has failed, thus preventing mechanical In his paper presented at the World Batch Forum techni- damage. cal proceedings in 1998, Christie9 provided his nine points Safety interlocking serves a different purpose from pro- for batch automation design: cess interlocking or permissive interlocking. Process interlocking can be safety-related, but it is primarily associated 1. Understand the process before generating the design. with the process. An example of a process interlock is to stop 2. Don’t implement until you have designed. charging a material if the agitator is not running. A permissive 3. Get the user involved in the design. interlock establishes an orderly progression of sequences. An 4. Document the design. example would be to not allow the feeding of an extruder before the barrel temperature has reached a minimum value. Raw materials ENGINEERING Phases Reactor Reactor Charge Heat A B Cool The effort to automate a batch facility is done to achieve Discharge operational benefits. Generally, benefits can be achieved through (1) increased production, (2) reduced utility costs, and (3) higher product quality. Many manufacturers use reduc- Ingredient 1 Centrifuge tion of off-spec materials due to operator error, which affects Ingredient 2 Tank feed tank all three of the above criteria, as justification for automation. Ingredient 3 For batch reactors, benefits acquired through increased Recycle production through automation can be achieved via reduced batch cycle times, minimized turnaround time between Centrifuges A - F batches, and better scheduling of reactors for like products. two trains Decreased cycle times for each reactor are certainly measur- able and are easy to quantify. A reactor cycle can be thought FIG. 8.3j of as having four separate steps: Batch process example.

5. Agree on the recipes. to support and enhance. A batch control system that fails to 6. I/O assignments are important. exploit the inherent flexibility of the plant and recipe devel- 7. Don’t underestimate the state transition matrix. opment that requires the assistance of control system devel- 8. Pay particular attention to exception handling, the hard opers will result in an implementation that cannot be flexible, part of batch. resulting in inflexibility of the organization to respond to 9. Batch reports are not an add-on. product needs.11 Sequential control functions can be diagrammed to Inherent in the message is that the design based upon express the logic of batch control. Such diagrams include S88 concepts allows easier implementation and a high degree paradigms such as ladder diagrams (change-oriented), matrix of modularity, translating into easier modifications and lower diagrams (state-oriented), flow diagrams (flow-oriented), maintenance costs. Today’s process automation suppliers petri-nets (data/flow-oriented), Gantt charts (state-oriented), have embraced the S88 standard concepts into their system and sequential function charts (GRAPHCETS). Many of architectures, facilitating more modular design and imple- these tools are listed as possible recipe formats.12,13 Most all mentation. process automation systems claim to be S88 based. In that With that, Fleming and Schreiber in their 1998 World regard, most, then, utilize function blocks for control modules Batch Forum paper on batch processing design10 counsels the and sequential function charts for procedures, unit proce- designer to consider process segmentation so as to: dures, or operations as their engineering tools to implement batch control automation. Identify the process cell first Figure 8.3k is an example of a batch procedure for the Identify the units after the boundary of the process cell batch process shown in Figure 8.3j. It shows the time sequence has been identified of activities in making a specific product. Between the active- Identify the equipment modules in the process cell and sequence phases, idling, holding, and waiting states can occur. units These states can allow information exchanges with other batch Identify control modules in all other modules process units or can receive directives from operators. Fail- Verify equipment module boundaries against defined safe, emergency, or exception handling states can also be procedural elements defined along with these phases. Verify unit boundaries against defined procedural ele- Formula information from the recipe is loaded into con- ments trollers at the proper time when executing the phases. For- Finally, verify the process cell boundary against mula information is a list of parameters, such as temperature defined procedural elements set points, flow set points, quantities or totalization set points for ingredients, transition times, controller modes, and what- The key to design is to segment the process properly so ever else is needed by the phases. that the controls can be equally identified and segmented. Poor Finally, at the end of the design and implementation segmentation results in a batch control system that is difficult aspects of automation design comes testing of the batch control

Preparation Premix Charging Reacting

Select reactor A prod A Reﬁll Set tank tank ready Tank Charge ready ? reactor A Reactor Heat ready reactor A ? Set reactor ready Cool reactor A

Dump reactor A

End report

FIG. 8.3k Batch procedure time sequence.

and automation. Pillai’s14 phase testing guidelines state to When the plant configuration is known, the steps neces- clearly define the modules, clearly define the testing strategy, sary to engineer the control of the process can be defined. clearly define the test plan, perform the tests, document the Figure 8.3l shows the engineering steps performed by the test results, and initiate change control. control engineer. However, many other kinds of disciplines

Start

Deﬁne the process cell

Deﬁne the unit typicals Reference the P&IDs

Deﬁne the individual units

Deﬁne common use Determine shared/exclusive Deﬁne measurements resources use resources Reference the P&IDs and control devices

Using standard control system Define actions upon auto, Define continuous and engineering tools Define modes/states/ semi-auto and man. discrete functions e.g., function blocks commands and their Similarly define actions for (equipment and ladder logic or other transitions states like hold, pause, run, control modules) representations of equipment suspend, etc. and control module functions Determine alarming strategy and actions associated with Determine unit procedures Define overall abnormal determine formula data- error conditions, such as Define recipes conditioning handling process inputs, parameters, putting the unit or batch to a and process outputs specific state like suspend

Design graphic, trend groups, Define the interface and messages, and other interfaces messages to required to the operator requires to Define unit procedures selecting and running the execute control recipes and recipe for the operator follow the batch as it runs Define SFC, time-sequence diagrams ladder logic structured text, or Define general Batch logs Define phase logic other language depictions performance and Batch historization for each entity and its management reports Batch reports interface from the recipe entity to its associated equipment entity End Define phase logic

FIG. 8.3l Batch process control ﬂowchart.

© 2006 by Béla Lipták 1540 Control and Optimization of Unit Operations actuators Sensors and Process control functions regulatory/descrete/sequential control Execute control Execute functions equipment recipe Unit supervisionUnit Unit recipes User information data Initiate & Initiate resources execution manage batch Manage batch supervise recipe Acquire, store & store Acquire, Batch reports recipe Control Batch management recipe to recipe to phasesto Recipe Batch procedure history to operations to information Create control Create Create/transform Create/transform Create/transform Create/transform to unit procedureto schedule recipe Production Master master recipes Site Store & manage Store to master recipesto recipe Create/transform site recipessite to site recipes Store & manage Store Create/transform recipe General (formula) data Product knowledge schedule Resource fi guration) (train con Create the production Equipment knowledgeEquipment batch historybatch Store and manage Store Construct general recipes general recipes Store & manage Store Procedure, plan process stages, process actions Plant knowledgePlant (raw materials,(raw etc.) Production process operations, & (chemist) analysis Process Business objectives Create the Product knowledge production plan users knowledge orders Information management planning Recipe management Customer Production Process & product Data & information to Data & information various & applications scheduling and © 2006 by Béla Lipták FIG. 8.3m activities. Consolidated control 8.3 Batch Control Description, Terminology, and Standard S88 1541 are involved in the entire process. Figure 8.3m illustrates the understandable by all who participate in it, regardless of the engineering activities required at various levels by people industry or the products involved. The goal is a modular, with different backgrounds and qualifications. maintainable, flexible batch automation implementation. Process and product knowledge from central engineering provides the input to construct basic phases for the procedure of making a product. This knowledge combined References with product knowledge of the research or development chemist is used to construct general recipes. Plant knowl- 1. ISA S88.00.01, “Batch Control, Part 1: Models and Terminology,” edge provides the information to convert the general recipe Research Triangle Park, NC: Instrument Society of America (ISA), to a site-specific recipe. Plant engineers also have the equip- 1995. 2. IEC 61512-1, “Batch Control, Part 1: Models and Terminology,” ment knowledge necessary to construct phase and operation International Electrotechnical Commission (IEC), 1997Ð08. logic and to transform the site recipe into a master recipe 3. ANSI/ISA-88.00.02, “Batch Control Part 2: Data Structures and by knowing the specific trains/lines on which the product Guidelines for Languages,” Research Triangle Park, NC: Instrument can be made. Process control engineers then are able to use Society of America, 2001. both system knowledge and process knowledge to create 4. IEC 61512-2-2002, “Batch Control, Part 1: Models and Terminology,” International Electrotechnical Commission, 2002. the control recipe, which is system-specific and is designed 5. ANSI/ISA-88.00.03, “Batch Control Part 3: General and Site Recipe to execute a batch. The control engineers also use their Models and Representation,” Research Triangle Park, NC: Instrumen- knowledge to design, configure, and implement the lower- tation, Systems, and Automation Society (ISA), 2003. level control functions required to provide process control. 6. ISA-88.00.04 Draft 3b, “Batch Control Part 4: Production Records,” Management information systems (MIS) people implement Research Triangle Park, NC: Instrumentation, Systems, and Automa- tion Society, 2003. process/product management and turn business objectives 7. Christie, D., “The Top-Down Approach to Successful Process Control and customer orders into a production plan that is used to Projects,” Control October 1989. create a production schedule. Batch history archives may 8. Reklaitis, G. V., “Scheduling Approaches for the Batch Processing be maintained by MIS or plant computer system personnel. Industries,” Proceedings of the World Batch Forum, Newton Square, Therefore, overall batch control implementation requires PA, May 1995. 9. Christie, D., “A Methodology for Batch Control Implementation — the talents of many disciplines. Real World Lessons,” Proceedings of the World Batch Forum, Balti- more, MD, April 1998. 10. Fleming, D. W., and Schreiber, P. E., “Batch Processing Design Exam- CONCLUSIONS ple,” Proceedings of the World Batch Forum, Baltimore, MD, April 1998. 11. Hancock, J., and Hopkinson, P., “A Case History of the Implementa- Execution of a batch process is a sequence of processing tion of an S88-Aware Batch Control System,” Proceedings of the stages, operations, or actions. These stages, operations, or World Batch Forum, Baltimore, MD, April 1998. actions are independent process-oriented events within the 12. ISA-TR88.0.03, “Possible Recipe Procedure Presentation Formats,” overall batch operation, such as charging, heating, reacting, Research Triangle Park, NC: Instrument Society of America, 1996. agitating, cooling, and discharging. These stages, operations, 13. Emerson, D., “What Does a Procedure Look Like? The ISA S88.02 Recipe Representation Format,” Proceedings of the World Batch and actions translate to unit procedures, operations, and Forum, San Diego, CA., April 1999. phases, which are defined by boundaries that define safe or 14. Pillai, V., “S88 Phase Testing and Change Management,” Control, logical points where one can charge an ingredient or direct March 1999. a finished product to a different downstream vessel. The set of sequences under which these are performed constitutes the batch operation. Bibliography The user must be considered at each level of the control activity. The operator interface allows the operator to inter- Hedrick, J. L., and Severns, G., “Planning Control Methods for Batch Pro- rupt automated commands received from higher activity lev- cesses,” Chemical Engineering, April 18, 1983, pp. 69Ð78. Rosenof, H. P., and Ghosh, A., Batch Process Automation, New York: Van els and to enter information or to command the process Nostrand Reinhold, 1987. directly. Data can enter the system at any level. Also, an “Batch Control Systems,” ISA Transactions, Vol. 28, No. 3, 1989. output can be generated at any level where it is needed and Faccenda, J. F., and Baker, T. E., “An Integrated AI/OR Approach to Blocked then be transmitted to the next higher or lower levels. Operations Scheduling,” Proceedings of the NPRA Computer Confer- ence, Seattle, WA, October 1990. The models defined by the ISA batch control standards Fisher, T. G., “Batch Control Systems: Design, Application, and Implemen- committee are designed to be valid for batch processing facil- tation,” Instrument Society of America, 1990. ities, regardless of the level of automation involved. The Hogenson, D. C., “Automatic Scheduling of Batch Operations,” InTech, control activity levels are designed to be collapsible in case April 1990, pp. 30Ð32. those functions are not applicable. From plants whose recipes Kompass, E. J., Witlock, S. K., and Williams, T. J., “Generic Control for are on paper and whose control is done by manual valves to Batch Manufacturing,” Proceedings of the Sixteenth Annual Advanced Control Conference, sponsored by the Purdue Laboratory for Applied fully automated paperless batch manufacturing facilities, the Industrial Control, Purdue University, and Control Engineering, West descriptions and terminology of the batch process should be Lafayette, IN, September 1990.

Feldmeyer, E., Alsup, M., and Burns, H., “Recipe Interface Requirements Lawrence, F. B., and Robinson, E. P., “Optimization Procedures for Sched- for Flexible Batch Control Systems,” Proceedings of the Industrial uling Batch Packaging Operations,” Proceedings of the World Batch Computing Conference, Vol. 1, Instrument Society of America, Ana- Forum, Houston, TX, April 1997. heim, CA, October 1991. Koning-Bastiaan, H., “Process Model and Recipe Structure, the Conceptual Ghosh, A., “An Approach to a Flexible and Easy to Use Batch Control Design for a Flexible Batch Plant,” Proceedings of the World Batch System,” Proceedings of the Industrial Computing Conference, Vol. 1, Forum, Houston, TX, April 1997. Instrument Society of America, Anaheim, CA, October 1991. Owen, J. M., “Evangelizing S88.01: Converting the Masses,” Proceedings Hornbeck, D., “A New Approach to Batch Process Control,” Proceedings of the World Batch Forum, Houston, TX, April 1997. of the Industrial Computing Conference, Vol. 1, Instrument Society of Wooley, K., and Christie, D., “Achieving Increased Batch Plant Productivity America, Anaheim, CA, October 1991. by Application of a Multi-Level DCS Solution,” Proceedings of the Larson, K., “Flexibility Takes Center Stage in Batch Process Automation,” ISA, Houston, TX, October 1998. Control, November 1991, pp. 24Ð33. Kawano, K., “Applications of Batch Progress Prediction by Rolling Sched- Massey, L. E., “The Development of Modular Batch Automation Tech- uling to Operation Support System,” Proceedings of the World Batch niques,” Proceedings of the Industrial Computing Conference, Vol. 1, Forum, Baltimore, MD, April 1998. Instrument Society of America, Anaheim, CA, October 1991. Emerson, D., and Himono, R., “Automated Scheduling in a Polymer Plant,” Nowicki, P. L., “Transforming Recipes is the Key to Flexible Batch Pro- Proceedings of the World Batch Forum, Baltimore, MD, April 1998. cessing,” Proceedings of the ISA/91, Vol. 46, Part 2, Instrument Society Akesson, K., and Tittus, M., “Modular Control for Avoiding Deadlock in of America, Anaheim, CA, October 1991. Batch Processes,” Proceedings of the World Batch Forum, Baltimore, Alsup, M., “Recipe Conﬁguration for Flexible Batch Systems,” ISA/93 MD, April 1998. Technical Conference, Chicago, September 19Ð24, 1993. Poulsen, L., “Paperless Batch Production — A Practical Example from the Tom, T. H., “DCS Selection for Flexible Batch Automation,” ISA/93 Tech- Pharmaceutical Industry,” Proceedings of the World Batch Forum, Bal- nical Conference, Chicago, September 19Ð24, 1993. timore, MD, April 1998. Bullotta, R., “Designing Effective User Interfaces for Batch Processes,” Musier, R., Sundaram, S., and Vardy, J., “The Recipe Model: New Advances Proceedings of the World Batch Forum, Phoenix, AZ, March 1994. in Using Life-Cycle Principle in the Batch Industry R&D and Manu- Offenbacher, F. M., and Smith, E., “Integrated Production Scheduling,” facturing Environment,” Proceedings of the World Batch Forum, Bal- Proceedings of the World Batch Forum, Phoenix, AZ, March 1994. timore, MD, April 1998. Korkmaz, B., and Pillai, V., “Unit Supervision— A Key Component in Van de Pol, P., “Real-time Production Scheduling in a Multipurpose Batch- Process Management and Process Control,” Proceedings of the World Oriented Environment,” Proceedings of the World Batch Forum, Phoe- Batch Forum, Baltimore, MD, April 1998. nix, AZ, March 1994. LeBlanc, L., and Malenfant, M., “How S88 Provides Consistency in Design Webb, M., “Computer System Implementation, Batch Standards, and Vali- and Terminology beyond Batch Processing,” Proceedings of ISA, dation,” Proceedings of the World Batch Forum, Newton Square, PA, 1998. May 1995. Jensen, B., and Lagonikos, P., “Automation Philosophy of a Pilot Plant for Rosenof, H., “Dynamic Scheduling for a Brewery,” Proceedings of the World Active Pharmaceutical Intermediates/Ingredients,” Proceedings of the Batch Forum, Newton Square, PA, May 1995. World Batch Forum, San Diego, CA, April 1999. Chappell, D. A., “Recipe Requirements for Dissimilar Manufacturing Trains: Brooks, T., “Batch-Based Historians,” Proceedings of the World Batch The Ultimate Complexity,” Proceedings of the World Batch Forum, Forum, San Diego, CA, April 1999. Newton Square, PA, May 1995. Korkmaz, B., Pillai, V., and Srinivasan, R., “Guidelines for Exception Han- Deitz, D., and Snyder, B., “Automating a Modern Bio-Manufacturing Plant: dling Design for Batch Processes,” Proceedings of the World Batch A Case Study,” Proceedings of the World Batch Forum, Toronto, ON, Forum, San Diego, CA, April 1999. May 1996. Zarichniak, S., “The Inherent Reusability of Batch Phases and Devices,” Gudaz, J., “Batch in the Context of Field-Based Control,” Proceedings of Proceedings of the World Batch Forum, San Diego, CA, April 1999. the World Batch Forum, Toronto, ON, May 1996. Crowl, T., and Wolin, D., “The Paperless Batch Plant,” Proceedings of the Nomikos, P., “Detection and Diagnosis of Abnormal Batch Operations,” World Batch Forum, San Diego, CA, April 1999. Proceedings of the World Batch Forum, Toronto, ON, May 1996. Kandadamy, S., and Ibrahim, E., “Automation of a Lube Oil Additives and Korkmaz, B., and Parapar, R., “Equipment Flexibility in a Pilot Plant Oper- Blending Plant Using an S88.01-Consistent Batch Software — a Case ation,” Proceedings of the World Batch Forum, Toronto, ON, May Study,” Proceedings of the World Batch Forum, San Diego, CA, April 1996. 1999. Clark, P., Grove, P., Liu, B., and Joglekar, G., “Using Simulation to Verify Kerrick, S., Smith, S., and Charpientier, L., “A Most Unusual Approach to the Decision Logic of Batch Control Systems,” Proceedings of the Implementing S88 Recipes,” Proceedings of the World Batch Forum, World Batch Forum, Toronto, ON, May 1996. San Diego, CA, April 1999. Uhlig, R. J., “Batch Control in a Resin Plant,” in ISA Practical Guide Series Nishitani, H., and Niwa, T., “Modeling & Simulation of Pipeless Batch for Batch Control, Research Triangle Park, NC: ISA, 1996. Plants,” Proceedings of the World Batch Forum, San Diego, CA, April Nisenfeldh, A. E., and Leegwater, H. (Eds.), Batch Control, Research Tri- 1999. angle Park, NC: ISA, 1996. Ito, H., and Emerson, D., “Integrated MMI for Batch Process Operations,” Berber, R., “Control of Batch Reactors: A Review,” Trans. IChemE., 74(A), ISA TECH, 1999. 3Ð20, 1996. Chen, L. W., Salisbury, R., and Kamal, S. Z., “Scheduling in Batch Process Sano, Y., Watanabe, H., and Yoshida, M., “Design Approach to Developing Plant Perspective,” IMS, 1999. the Batch Control System,” Proceedings of the World Batch Forum, Adler, D., “Trends in Manufacturing,” Interkama Technical Conference, Houston, TX, April 1997. Dusseldorf, Germany, 1999. Tom, T. H., “Handling Product Related Exceptions Using the S88 Concept Liefeldt, A., Lohl, T., Stobbe, M., and Engell, S., “Simulation and Sched- of Modular Batch Automation,” Proceedings of the World Batch uling of Recipe-Driven Batch Processes Based on a Single Data Forum, Houston, TX, April 1997. Model,” Interkama Technical Conference, Dusseldorf, Germany, 1999. Choi, J. Y., Mercure, P. K., and Rhinehart, R. R., “Optimization of a Batch Koning-Bastiaan, H., Schreil, C., and Roy, C., “Automated Execution of Bio Polymerization Reactor,” Proceedings of the World Batch Forum, Tech Batch Manufacturing,” Interkama Technical Conference, Dussel- Houston, TX, April 1997. dorf, Germany, 1999.

Parshall, J. H., and Lamb, L. B., “Applying S88: Batch Control from a User’s Johnson, L., and Roy, C. “Use of Web Technologies in Batch Management,” Perspective,” Research Triangle Park, NC: ISA 1999. Proceedings of the World Batch Forum, Orlando, FL, April 2001. Brandl, D., “Using Corporate Recipes to Accelerate Time to Market,” Aspen- Givens, M., and McDonald, A., “Repeated S88 Success Yields Cost Reduc- world 2000 Technical Session, Orlando, FL, February 2000. tions at Large Consumer Products Company,” Proceedings of the World Brandl, D., “Batch Automation Is Coming of Age,” Chemical Processing, Batch Forum, Orlando, FL, April 2001. September 2000. Christie, D., “Life’s a Batch,” InTech, July 2001. Huzmezan, M., Gough, B., Kovac, S., and Le, L., “Advanced Control of Blanchard, I., “Batch Control Systems Current and Future,” Proceedings of Batch Reactor Temperature,” Proceedings of the ISA Expo, 2000. the World Batch Forum, Woodbridge Lake, NJ, April 2002. Drillenburg, C., “Tracking and Tracing on an ISA S88 Foundation,” Pro- Årzén, K.-E., and Olsson, R., “Exception Handling in S88 Using Grafchart,” ceedings of the ISA Expo, 2000. Proceedings of the World Batch Forum, Woodbridge Lake, NJ, April Benton, A., “Batch Control Application Frameworks and Reuse,” Proceed- 2002. ings of the World Batch Forum, Atlantic City, NJ, April 2000. Marklew, C., “Electronic Batch Records and Flexible Batch Reporting,” Fisher, T. G., “Batch Control: Applying the S88.01/IEC 61512-1 Standards,” Proceedings of the World Batch Forum, Woodbridge Lake, NJ, April Proceedings of the World Batch Forum, Atlantic City, NJ, April 2000. 2002. Brandl, D., Emerson, D., and Ward, B., “Batch Schedules and Production Staus, R., “Improved Temperature Control in Batch Production Systems,” Schedules: Which Should You Use?” Proceedings of the World Batch Proceedings of the ISA, 2002. Forum, Atlantic City, NJ, April 2000. Holy, R., and Pozivil, J., “Batch Control System Project for a Pharmaceutical Roy, C., and Wyshak, G., “Implementing Automated Batch Control of a Plant,” ISA Transactions, 2002. Biotechnology Manufacturing Facility Using S88.01 Concepts: A Case Sanchez, A., Rotstein, G., Alsop, N., Bromberg, J. P., Gollain, C., Sorensen, Study,” Proceedings of the World Batch Forum, Atlantic City, NJ, April S., Macchietto, S., and Jakeman, C., “Improving the Development of 2000. Event-Driven Control Systems in the Batch Processing Industry: A Himono, R., Mano, K., and Takahata, K., “An Integrated System with Batch Case Study,” ISA Transactions, 2002. Functions and Front-End Scheduling Based on S88: Application to Lorenzo, D., and Pérez, N., “Applying Model Predictive Control to a Batch Beverage Plant,” Proceedings of the World Batch Forum, Atlantic City, Process,” Proceedings of the World Batch Forum, Woodbridge Lake, NJ, April 2000. NJ, April 2003. Koning-Bastiaan, H., “Production Information Management,” Proceedings Pettus, N., and Wolf, D., “Automated Batch Scheduling and MES Integration of the World Batch Forum, Atlantic City, NJ, April 2000. Using a Hierarchical Based, Batch Control Software Architecture,” Stapper, H., and Verhagen, A. M., “Beneﬁts of Advanced Engineering Meth- Proceedings of the World Batch Forum, Woodbridge Lake, NJ, April odologies for the Design and Support of Batch Projects in the Phar- 2003. maceutical Industry,” Proceedings of the World Batch Forum, Brussels, Arnold, J., and Brandl, D., “Automating the Manufacture of Highly Ener- Belgium, October 2000. getic Organics Using the S88 Model,” Proceedings of the World Batch Rickard, J., “Combining Optimal Off-Line Scheduling with On-Line Super- Forum, Woodbridge Lake, NJ, April 2003. visory Control,” Proceedings of the World Batch Forum, Brussels, Hunter, M., “Real-Time Batch Control and Materials Management in Per- Belgium, October 2000. fume Production,” Proceedings of the World Batch Forum, Woodbridge Hauff, T., “Batch Manufacturing: Status and Future Challenges,” Proceed- Lake, NJ, April 2003. ings of the World Batch Forum, Brussels, Belgium, October 2000. Clark, S. C., “S88 Design and Implementation Case Study for a Complex Ghosh, A., “Maximizing the Potential of Batch Process Control,” Proceed- Bulk Pharmaceutical Batch Process,” Proceedings of the World Batch ings of the World Batch Forum, Brussels, Belgium, October 2000. Forum, Woodbridge Lake, NJ, April 2003. Morse, C., “S88 Case Study for Improved Production Flexibility, Safety, Brill, E., and Yulevitch, O., “Targeting Batch Outcome Using Predictive and Environment,” Proceedings of the World Batch Forum, Brussels, Control,” Proceedings of the World Batch Forum, Woodbridge Lake, Belgium, October 2000. NJ, April 2003. Craig, L., “S88 Process Modularization,” Proceedings of the World Batch Parks, J., and Yuki, T., “Using Alarm and Event Analysis to Achieve Batch Forum, Brussels, Belgium, October 2000. Productivity Improvements,” Control Solutions, February 2003. Vanhove, G., “Tracking and Tracing on an ISA S88 Foundation,” Proceed- Bonvin, D., and Srinivasan, B., “Optimal Operation of Batch Processes via ings of the World Batch Forum, Brussels, Belgium, October 2000. the Tracking of Active Constraints: A Case Study,” ISA Transactions, Amkreutz, R., and van Beurden, I., “Safety in Batch Production,” Proceed- Research Triangle Park, NC: 2003. ings of the ISA Expo, 2001. Gough, B., Kovac, S., Devito, L., and Quick, D., “Model Predictive Jensen, B. A., “Six Sigma and S88 Unite for Batch Automation Productivity Control of Batch Temperature,” Proceedings of the World Batch Improvement,” Proceedings of the World Batch Forum, Orlando, FL, Forum, Chicago, IL, May 2004. April 2001. Fu, C., “Functions to be Considered in Batch Material Transfer Controls,” Christie, D. A., “Automatic Adaptation of Batch Logic to Changing Field Auto- Proceedings of the World Batch Forum, Chicago, IL, May 2004. mation,” Proceedings of the World Batch Forum, Orlando, FL, April 2001. Brun, T. A., “Transfer Lines as Unit in an S88 Frame,” Proceedings of the Wilson, P., “Batch Application Migration,” Proceedings of the World Batch World Batch Forum, Chicago, IL, May 2004. Forum, Orlando, FL, April 2001. Marjanovic, O., Lennox, B., Lovett, D., and Sandoz, D., “Statistical Process Branch, T., and Ray, T., “Batch Automation Project Increases Production,” Monitoring of Industrial Batch Processes,” Proceedings of the World Proceedings of the World Batch Forum, Orlando, FL, April 2001. Batch Forum, Mechelon, Belgium, October 2004. Crowl, T. E., and Heckmanski, J., “Design Methods to Defer Costs on Batch Martin, E., and Morris, J., “Monitoring Multi-recipe Batch Manufacturing Projects,” Proceedings of the World Batch Forum, Orlando, FL, April 2001. performance,” Proceedings of the World Batch Forum, Mechelon, Kovacs, K., “Designing Batch Systems for e-Manufacturing,” Proceedings Belgium, October 2004. of the World Batch Forum, Orlando, FL, April 2001. Mecchretto, S., “Integrated Batch Processing: A Recipe fpr Advanced Man- Patnaik, S., “Master Batch Record Management,” Proceedings of the World ufacturing in the Process Industries,” Proceedings of the World Batch Batch Forum, Orlando, FL, April 2001. Forum, Mechelon, Belgium, October 2004.