Pressure drop in pipe lines and fitting. Part-1

Pressure plays a prominent role in driving and arresting the fluid flow from one place to another. What exactly is this pressure? One classical definition is

Pressure is force acted per unit area

How to design a P&ID? Part-3

Earlier two parts of designing a P&ID were from process perspective of a P&ID. Now in this present part we will deal with the instrument aspects of a P&ID. Some of the most common instruments which we are using in process industry are transmitters, gauges, indicators, control valves, on off valves etc. The parameters which we are interested may be flow, temperature, pressure, concentration etc. Before going to discuss further about instrumentation part in P&ID it is better to get familiarized with the instrumentation terms. Let’s get started

How to design a P&ID? Part-2

Pipe line representation

Pipe lines should be shown with an orthogonal arrow mark i.e, You should not mention the arrow mark in the middle of line. Always represent the arrow at the pipe right angles in the drawing.

 

How to design a P&ID ? Part-1

Designing a P&ID Part-1

In this part we will see the legend and symbols using in P&ID now days. Please note that the legend and symbols may vary from one process designer to another and the reader should understand that. Following sections will give a brief idea about P&ID representation.

Pipe line number

X” – AB – CDEF – GHI – J

X = Pipe line size.

AB = Service Code (Arbitrary for Chlorine I can take as CL).

CD = Last two digits of drawing number.

EF = Line sequence number.

GHI = Line material of construction.

J = Insulation thickness.

Example:

                6” – CL – 0102 – CS – 40H

The above line is 6 inch pipe in chlorine service present in a drawing whose number ends with 01 and it is second such line in the drawing. Also the material of construction is Carbon Steel with 40mm thick hot insulation.

Service code, pipe material, insulation notation varies from one company to another. Some companies also use color coding to easily differentiate the lines in colored P&ID.

Area numbers

In order to easily review a section in P&ID it is always better to allot specific number for that particular unit. Consider the following example.

31: Raw material processing section.

32: Reacting section.

33: Purification section.

34: Storage/Packing/Drumming section.

So if I say, I am using a roll crusher in 31 section, I am actually referring roll crusher present in raw material processing section.

Equipment tag format

In a process industry we use lot of process equipments (pumps, vessels, exchangers, reactors etc,). Calling a pump with its true name like “Propylene glycol distillation column bottom pump” may create confusion. Also it is cumbersome enough to mention with its original name all times. So we use a notation which conveys the equipment name tidy. Generally the equipment tag name will be of the form

AN – EQ – SN

AN: Area Number

EQ: Equipment type code

SN: Sequence Number

For Example

03 C 3204

The above tag name corresponds to a fourth (04) column (C) in reacting section (32), whose area number is three (03).

Again some companies follow three digit tag number and some four digits. It is purely based on the company discretion. For equipments we can use the following notation.

Code	Equipment
A	Agitator
C	Distillation columns, absorption columns, scrubber, packed columns
D	Drums
E	Exchangers
EJ	Ejectors
F	Filter
G	Decanters, Centrifuges
H	Hydro cyclones
J	Hoppers, Bunkers
K	Compressors, Blowers
L	Vacuum pumps
M	Mixers
P	Pumps
R	Reactor
SM	Static Mixers
T	Tanks
V	Vessels

What is a P&ID?

GATE 2015 Chemical Engineering

Gear up for the next biggest challenge in your career, GATE-2015 online application starts from September 1st 2015. GATE (Graduate Aptitude Test in Engineering) is a common way to enter into masters, doctorial programs and public sector undertaking (PSU) companies. This time IIT Kanpur is organizing GATE-2015. http://gate.iitk.ac.in/GATE2015

GATE-2015 Chemical Engineering (CH)

It is better to start the preparation 3 to 4 months before the commencement of exam. Practice is the mantra. The more you practice the more you will be benefited. It will be useful to solve the numerical questions. The easiest way to gain more marks is to concentrate on Aptitude, English, and Mathematics. From technical side Process calculations, Chemical technology subjects are easy to gain more marks. Fluid mechanics, Process economics, thermodynamics are easier to solve next. Chemical kinetics, Heat and mass transfer subjects come in next place. The order should be decided by you ultimately based on your preparation. Follow www.Chemineering.blogspot.com to get updates on GATE-2015 and other Chemical engineering related stuff.

#Chemieering recommends the following books for GATE-2015 preparation in Chemical engineering stream.

GATE-2015 Highlights

• GATE-2015 application fees is Rs 1500/- for male candidates in General/OBC category and Rs 750/- for female candidates. For SC, ST, PwD candidates the fees is Rs 750/-.
• Payments have to be made through debit/ATM cards, credit cards or internet banking and e-challan only
•  All Supporting documents should be sent online only. No hard copy will be accepted
• Examinations for all the 22 papers will be conducted by an ONLINE Computer Based Test (CBT). The online examination paper will contain some questions for which numerical answers must be keyed in by the candidate using the virtual keypad. Rest of the questions shall be of Multiple Choice Question (MCQ) type.
• GATE 2015 examinations will be held during forenoon and afternoon sessions on alternate weekends (Saturday and Sunday) between 31st January 2015 and 14th February 2015. Examination for some of the papers in GATE 2015 will be held in multiple sessions. Exact details regarding complete examination schedule will be notified at a later date.
• The payment of application fees would be online through different modes like net banking, debit/credit card, e-challan, etc.
• GATE 2015 score is valid for THREE YEARS from the date of announcement of the results.
• During the online GATE 2015 examination, all candidates will be provided with an online scientific calculator which has to be used to answer the questions.

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