Types of Chemical engineering drawings - BFD, PFD, P&ID

The terms flow sheet and flow diagrams are often used in engineering and design applications. But this is not the accurate way to describe the process drawings. This post will give a glimpse about the types of process drawings.

Basically there are three types of process diagrams in chemical engineering context.

1. BFD - Block Flow Diagrams.
2. PFD - Process Flow Diagrams.
3. P&ID - Piping and Instrumentation Diagrams.

In a brief BFD represents entire process in a single sheet, where as in PFD you can find some detailed information like plant operating conditions, process flow. It uses symbols to represent the equipment. P&IDs provide detail information when compared to above two drawings. They use standard nomenclature, symbols, and tag numbers to fully describe the process.

These drawings are very useful as they convey the right amount of process information as needed during various stages of bidding, engineering design, procurement, construction, operating & decommissioning phases of the process.

BFD-Block Flow Diagram

A BFD has the ability to represent the complete process on a little more than a single sheet. It contains mainly text enclosed by boxes, interconnecting lines with flow arrows. In some BFDs mass flow rates may be mentioned so as to describe the material balance over the entire plant.

PFD-Process Flow Diagram

PFDs contain more information than the block flow diagrams from which they are derived. They show more detail about major equipment, subsystems and the flow of product between them. A typical PFD contains equipment symbols connected by process lines where temperature and pressure information are shown on the line itself. You can easily refer the properties of a particular stream through stream number. For designing a P&ID, equipment layout PFD is mandatory.

P&ID-Piping and Instrumentation Diagram

P&IDs carry a lot of information to define the process. Derived from PFD it is the best way of accurately documenting the operation of a process. P&ID takes the conceptual aspects of PFD and expand them by adding 

1. Detailed symbols.
2. Detailed equipment information.
3. Equipment order and process sequence.
4. Process and utility piping.
5. Process flow direction.
6. Major and minor bypass lines.
7. Line numbers, Pipe spec, Pipe size.
8. Isolation and shut off valves.
9. Instrumentation controls.
10. Types of process component connections.

A P&ID can be best understood with the help of a legend sheet given by the P&ID developer. Legend sheet contains information regarding the nomenclature, tag philosophy, symbols, a lot more. Download the PDF files to know more about drawings and legend sheet.

For detail information on BFD, PFD and P&IDs download the following PDF files.

Download PDF file for Piping and symbols

 

 

Download PDF file for BFD, PFD, P&ID

Top 10 books for Chemical Engineering beginners.

Whether you are a student or a engineering professional,some books will have lot of impact in your real life. Following books will give wide knowledge in the Chemical Engineering field.

1. Unit operations of Chemical engineering.

One of the oldest books from McGraw Hill book house, Unit operations of Chemical engineering can be considered as a bible for Chemical Engineers. This book is widely using in universities as a basic text for Chemical engineering. If you want to learn basics then this book is for you.

Each section has been framed in a perfect manner for learning step by step. At the end of each chapter you can find lot of problems which will be useful for practice.

Name     - Unit operations of Chemical engineering.
Author  - Warren Lee McCabe, Julian Smith, Peter Harriot.

2. Introduction to Chemical engineering thermodynamics.

Another productive book from McGraw Hill, Introduction to Chemical Thermodynamics is a comprehensive book that starts from basic concepts and end up with a detail description of real gas behavior, solution thermodynamics. Generally solution thermodynamics, real gas behavior is much useful in Chemical and Process industry. Some of the equations from this book found their place in famous simulators which will give the real time values for a given temperature, pressure data. Problems at the end of each chapter will enhance your thermodynamics knowledge.

Name     - Introduction to Chemical Engineering thermodynamics.
Author  - Joseph Mauk Smith, Hendrick C. Van Ness, Michael M. Abbott 

3. Chemical Process Principles Part-1

In every industry, material and energy balance across a given operation is of immense value. So if you want to ace the material and energy balance this is must book. It will give a glimpse about vapor pressure,humidity, saturation, excess air problems, limiting reagent, crystallization etc.,These principles are much useful to solve mass and momentum transfer problems.

Name     - Chemical Process Principles Part - 1.
Author  - Joseph Mauk Smith, Hendrick C. Van Ness, Michael M. Abbott 

4. Mass transfer operations 

Mass transfer in general involves transfer of material from one phase to another phase.And the mass transfer operations include Absorption, Distillation, Extraction, Leaching ,Stripping etc.,These operations are explained in a precise manner in this book.Also you can find the mass transfer equipment design fundamentals. You can gain stringent experience by calculating mass transfer problems as you will encounter lot of practical problems at the end of every chapter.

Name     - Mass Transfer Operations.
Author  -  Robert E. Treybal

5. Heat Transfer

Heat transfer is a important operation in every industry (Chemical, Process etc.,) because if you save energy you save money. As a beginner or a engineering professional if you have this book,then you can excel in heat balance calculations, heat exchangers, heat exchanger designs. The data present in this book is of immense value in chemical industry. Every chapter has been explained with clear illustrations. Even it is useful for Mechanical engineers.

Name   - Heat Transfer.
Author  - J.P Holman

6. Chemical reaction engineering

Chemical reaction engineering is important for determining the reactor size, reactor type, temperatures and pressures required for the reaction. Reactions kinetics plays a major role in chemical industry, particularly in fertilizer and pharma sector. In this particular book you can learn about half time, conversion rates, first order reactions,second order reactions,batch reactors, continuous stirred tank reactors (CSTR), plug flow reactors (PFR), activation energies, catalyst effect etc.,

Name   -  Chemical reaction engineering.
Author  -  Octave Levenspiel.

7. Process system analysis and Control

Now a days every industry is automated, automated in the sense you can monitor the chemical plant from a distributed control system in a control room. In the Process system analysis and control book the author has described how a signal (pressure, temperature, flow etc.,) can be sent to the controller and how the controller functions. This book will give a glimpse about Laplace transforms, first order systems, second order systems, open loop ,closed loop transfer functions, control systems, control valves etc., Check out the book for more!

Name   - Process system analysis and control.

Author  - Donald R.  Coughanowr.

8. Plant Design and Economics for Chemical Engineers

Plant design and economics for a chemical engineers is a very good book on process economics, HAZOP, SWOT analysis, interest calculator, loan repayment, income tax deductions etc., in short it is a non technical book with equal technical importance. You can learn management basics from this book.

Name  -  Plant design and economics for Chemical engineers.

Authors  - Max S. Peters, Klaus D. Timmerhaus

9. Shreve's Chemical process industries

Knowing about Chemical process principles and operations is one part, but knowing about several prominent Chemical process is required. For this Shreve's chemical process industries is a good book. This book is a collection of several chemical process, fertilizer industries, paints oil refineries, sugar industries,ceramic industries, glass industries, etc.,It hilights the major operations involving in that particular process.

Name   - Shreve's Chemical process industries.
Author -  George T.Austin

10. Transport Phenomena

Some of the complex problems in chemical engineering are derived from the basic equations mentioned in the above books. This book provides insight into practical problems that occur in every chemical industry, this includes velocity distributions for newtonian and non newtonian fluids, mass tansfer , heat transfer problems etc.,After reading this book you can solve almost every problem by using the shell balance concepts.

Name  -  Transport Phenomena.

Authors - Warren E Stewart, R. Byron Bird, and Edwin N. Lightfoot 

What is the difference between Chemistry and Chemical Engineering ?

Have you ever came across this question, what is the difference between Chemistry and Chemical engineering ? To put in simple words Chemistry mainly deals with the chemical aspects (like pH, electromotive force, reaction with water etc.,) of the chemicals, where as if you pick Chemical Engineering it deals mainly with physical aspects (like density, viscosity, diffusivity, boiling point etc., ). But you can find some properties commonly using in both streams.

Chemist work:

In general chemists take care of chemical reaction rates, properties of matter, research involved in the production of new chemicals. They use wide variety of equipment in laboratory to analyze the chemical behavior,composition, conductivity, pH, polarity, surface tension etc.,For example the reaction between a polar molecule and a organic compound depends on the affinity between those two chemicals. also the composition, pH of the products after the reaction will be given by the chemists.

Chemical engineer work:

Chemical engineers use the data provide by chemists to design a chemical industry. They much involve in designing the distillation columns, extractors, pressure vessels, reactors, by using the physical properties of chemicals. For example in a distillation column, temperature at the top and bottom of the column have predominant effect on the purity of chemicals.Chemical engineers used to work on simulators to solve complex problems related to process in a chemical industry.

Job profiles:

Chemists with post graduation and Ph.D have bright opportunities in the field of research. Also they can opt to work as chemists and R&D technicians with graduation.
Chemical engineers on the other hand have wide opportunities in the field of process engineering, design of chemical plants, chemical plant operation etc.,