Practical Batch Process Management

Mike Barker, Jawahar Rawtani

• Publisher: Newnes
• Year: 2004
• ISBN:
  9780080455433
• Topic: Business
• Subtopic: Operations
• Index: Business

Historically batch control systems were designed individually to match a specific arrangement of plant equipment. They lacked the ability to convert to new products without having to modify the control systems, and did not lend themselves to integration with manufacturing management systems. Practical Batch Management Systems explains how to utilize the building blocks and arrange the structures of modern batch management systems to produce flexible schemes suitable for automated batch management, with the capability to be reconfigured to use the same plant equipment in different combinations. It introduces current best practice in the automation of batch processes, including the drive for integration with MES (Manufacturing Execution System) and ERP (Enterprise Resource Planning) products from major IT vendors. References and examples are drawn from DCS / PLC batch control products currently on the market.- Implement modern batch management systems that are flexible and easily reconfigured - Integrate batch management with other manufacturing systems including MES and ERP - Increase productivity through industry best practice

1

Introduction

Publisher Summary

This chapter presents an introduction to the batch process for manufacturing along with its comparison to other manufacturing processes. The manufacturing industry has drawn its efficiency from large-scale continuous processes over a long period. Continuous processes dominate in the manufacturing of bulk chemicals. However, for manufacturing fine and specialty chemicals, with the increased emphasis on and customer requirements of high quality, equal focus has been on batch processing. The chapter presents the economic and technical factors that make batch processes favorable over continuous processes: (1) Batch processes often consist of simple processing units like mixers and stirrers, (2) a batch processing unit may be multi-purpose—it may be used for several processing phases of the batch and could support multi-product manufacturing within the facility, and (3) batch manufacturing plants are comparatively more robust than a continuous plant. Depending on the output of the process, industrial processes are classified into continuous process, discrete process, and batch process. The chapter explains the types of batch processes, the background of the need for integrated batch systems, and presents an overview of batch systems engineering.

1.1 Introduction

The manufacturing industry has drawn its efficiency from large-scale continuous processes over a long period. Initially, the manufacturing facility for a new product used to be either a batch process or a laboratory process on a larger scale. But as the economy of scale was key to success in business, chemical engineering and process industries focused all attention on designing and developing continuous processes. Continuous processes are dominant in manufacturing of bulk chemicals. However, for manufacturing fine and specialty chemicals, with the increased emphasis on and customer requirements of high quality, equal focus has been on batch processing. Today, almost half of the processes in industry are batch processes.

Following are the economic and technical factors that make batch processes favorable over continuous processes:

• Batch processes often consist of simple processing units like mixers and stirrers.

• A batch processing unit may be multi-purpose – it may be used for several processing phases of the batch and could support multi-product manufacturing within the facility.

• Batch manufacturing plants are comparatively more robust than a continuous plant.

• Batch process manufacturing facility is easier to scale up depending on market demand and requirements.

1.1.1 Classification of processes

Industrial processes are classified depending on the output of the process as:

• Continuous process

• Discrete process

• Batch process.

Continuous process

In a continuous process, there is continuous flow of material or product. Processing the materials in different equipments produces the products. Each equipment operates in a single steady state and performs specific processing function.

Some examples of continuous processes are generation of electricity, Cement/Clinker production, paper mill and so on.

Discrete process

In a discrete process, the output of the process appears one-by-one or in discrete quantities. The products are produced in lots based on common raw materials and production history. In discrete process, a specified quantity of products moves as a unit or group of parts between workstations.

Some examples of discrete processes are assembly of watches, production of cars, assembly of television set, etc.

Batch process

In a batch process, the output of the process appears in quantities of materials or lots. A batch process has a beginning and an end. Batch processes are neither continuous nor discrete, but have the characteristics of both. Batch process is usually performed over and over. The product of a batch process is called a batch. Batch processes define a sub-class of sequential processes. Batch processes generate a product but the sequential processes need not necessarily generate a product.

Some examples of batch processes are beverage processing, biotech products manufacturing, dairy processing, food processing, pharmaceutical formulations and soap manufacturing.

1.2 Identification of batch processes

A batch is defined as:

• The material that is produced by a single execution of a batch process, or

• An entity that represents the production of a material at any point of time in the process.

Here, it is important to note that the term ‘batch’ means both the material produced by and during the process, and also an entity that represents the production of that material. The term ‘batch’ is used as an abstract contraction for the words – the production of a batch.

We have seen classification of processes based on their outputs. Now we will formalize the definition of a batch process:

• A process is considered to be a batch process if, due to physical structuring of the process equipment or other reasons, the process consists of a sequence of one or more steps that must be performed in a defined order. And, on completion of the sequence of the steps a finite quantity of the finished product is produced. The sequence is repeated to produce another batch of the product.

• A batch process is a process that leads to the production of finite quantities of material by subjecting quantities of input raw materials to an ordered set of processing activities over a finite period of time using one or more equipments.

1.2.1 Batch processes

Today many products are produced using continuous processes that were originally produced using bat...

Table of contents

• Cover image
• Title page
• Table of Contents
• Preface
• Chapter 1: Introduction
• Chapter 2: Identify and define physical models
• Chapter 3: Identify and define process models, actions, operations and stages
• Chapter 4: Identify and define procedural models
• Chapter 5: Introduction to recipes
• Chapter 6: Batch manufacturing basics
• Chapter 7: Batch and sequence programming fundamentals
• Chapter 8: Practical techniques in sequence control design
• Chapter 9: Operator and supervisor interface
• Chapter 10: Batch management issues
• Chapter 11: Batch control technologies
• Chapter 12: Practical software project planning and implementation
• Exercise 1
• Exercise 2
• Exercise 3
• Exercise 4
• Exercise 5
• Appendix A: Modular approach
• Appendix B: Case study of batch automation in a biotech manufacturing plant
• Glossary
• Solution 1
• Solution 2
• Solution 3
• Solution 4
• Solution 5
• Index