I have encountered a lot of fresh chemical engineering graduates from college who joined as "trainees" in the engineering consultancy field and inevitably they have a lot of questions on what process design engineering is all about?
Some of the frequently asked questions (FAQ's) are what are the activities that a process design engineer do, what are the growth prospects and financial rewards, what is meant by computer aided process design & how a project is executed.
Based on some such questions, I have tried to establish FAQ's for what a chemical engineer needs to know when he or she joins an engineering consultancy.
Here is how it goes:
Q. What is Chemical Process Design Engineering?
A. It is an activity wherein the process engineer is supposed to perform any one or all of the activities as mentioned below to provide documentation for a safe, reliable and profitable design:
a. Design new equipment/unit/plant as per good and internationally accepted engineering practices
b. Rate or check adequacy of existing equipment/unit/plant for changed operating conditions (e.g. pressure, temperature, flow etc.) as per good and internationally accepted engineering practices.
Q. What are the long-term career and financial prospects as a process design engineer?
A. At the entry-level when a chemical engineer starts his or her career as a "Trainee Process Design Engineer", the salary could start from anywhere upwards of USD 25K to 30K per annum. As the person rises in his or her career with experience the salary for a Senior or Principal process engineer could be upward of USD 50K per annum as of today. For a departmental head position or engineering manager position the salary would definitely be upward of USD 70K per annum. Overall, the growth prospect and financial rewards as a process engineer are very good. Process engineering design can be utilized for as diverse fields as upstream Oil & Gas, Refining, Petrochemicals, Fine chemicals, Pharmaceuticals, Energy (conventional and non-conventional), Water resource management, Environmental management etc.
Other rewards and benefits working as a process engineer could be:
a. Traveling all over the globe to execute projects.
b. Bonuses for timely and qualitative execution of the project
c. Enhanced learning through attending seminars, training programs and last but not the least for men
d. getting to marry a pretty girl of your choice considering your status as a respected technocrat in the society. [Admin Note: We're certain that this is meant to be flattery. We do realize to not all well respected females are seeking a process engineer]
Q What documentation needs to be prepared as part of the process engineer's job?
A. Most common process engineering documents during execution of any project may be as follows:
a. Basis of Design
b. Process Flow Diagrams (PFD's)
c. Heat & Mass Balance
d. Piping & Instrument Diagrams (P&ID's) also sometimes known as Process & Instrument Diagrams
e. Equipment Process Datasheets. These include but are not limited to:
i Atmospheric Storage Tanks
ii Pressure Vessels
iii Distillation Columns
iv Heat Exchangers
ix Reaction Vessels (Reactors)
xi Package Units (e.g. Nitrogen Generation Plants, Fired Heaters/furnaces, Compressed Air plants, Steam Boiler Plants, Water Treatment Plant etc.)
i Pressure Measurement Instruments
ii Temperature Measurement Instruments
iii Flow Measurement Instruments
iv Level Measurement Instruments
v Control Valves (Pressure, Temperature, Flow, Level)
vi Automatic On-Off Valves
vii Safety Valves
viii Analytical Instruments (e.g. Moisture Analyzer, pH analyzer, Viscosity Analyzer, Gas/Liquid Chromatographs, Specific Gravity analyzers, Oxygen Analyzers, Calorimeters, Gas Analyzers)
ii Traps (Steam, Moisture)
iii Special Valves
iv Inline sampling devices
v Piping Injection Devices
vi Special pipe fittings (spray nozzles, eductor devices
i. Line List
j Electrical Load List
k. Operation, Control & Safeguarding Philosophy
l. Hazard & Operability Studies (HAZOP) Review and Closeout Report
Q. When can process engineering be started?
A. Process engineering can be started based on one or more of the following:
a. Process description which normally would include the process chemistry, unit or plant design capacity, major unit operations involved
b. Drawings / documents related to existing plant / unit where the scope of work involves revamp or debottlenecking
c. Concept report which gives broad outline for various process routes to be adopted for manufacturing a particular chemical(s).
A. Well, to start with you definitely need your scientific calculator. Other than that, a wide variety of tools can be employed to go about your task of process engineering.
Listed below are a few of them:
a. Graph sheets for hand calculations and drawing sketches. Many old-timers still use A4 or letter size graph paper for doing heat and mass balance & sizing calculations for the various unit operations of the plant/unit in question.
b. Using Microsoft ExcelŽ for tables, sketches, graphs and calculations. This is one of the most widely practiced and popular way of doing process engineering in today's world.
c. Using specialized process engineering software for generating PFD's, P&ID's, heat and mass balance calculations, pump hydraulics, equipment sizing, line sizing etc. Some of the most widely used software for doing process engineering calculations and drawings are:
i HYSYS by "AspenTech" for heat & mass balance and equipment sizing / rating
ii PIPESIM by "Schlumberger" for steady state simulation of multiphase pipeline flow
iii PIPEPHASE by "Simulation Sciences" for steady state simulation of multiphase pipeline flow
iv OLGA by "Scandpower" for steady state and transient simulation of multiphase pipeline flow
v CHEMCAD by "Chemstations" for heat and mass balance and equipment sizing / rating
vi AUTOCAD by "Autodesk" for generation of PFD's & P&ID's
Other than the above mentioned software there are numerous other software available which may be used for process design. Many clients or operating companies specify the software to be used for process design when a project is executed for them by an engineering consultant. In such cases the engineering consultant may require to purchase or lease the software for performing the engineering. Unlicensed or pirated versions of software are not acceptable to most clients and their usage is considered as unethical. All good engineering / consulting companies follow certain self-imposed codes and guidelines for preventing and discouraging unethical business practices including usage of pirated software. Make sure that you study and follow the ethical business practices of your company. Consequences of unethical behavior are loss of credibility, lost business opportunities and as an extreme, immediate termination of employment and / or criminal proceedings against you or your company.
A. These are the allotted hours (time) for performing a given activity. Process engineering itself being an activity, there may be a chunk of man-hours allotted for process engineering. As an example, if 5000 hours are allotted for the process discipline for a given project, the entire process engineering activity needs to be completed within this time frame starting from the zero date. The span for process engineering may vary depending upon the availability of man-power. Again as an example if 3 engineers and 2 draughtsmen are working full time for the given project and the available man-hours per person are 160 per month, then the total man-hours consumed per month would be 160 X 5 = 800. This means the overall time frame for execution of the process engineering activity would be 5000 / 800 = 6.25 months.
Man-hours may be further split into small individual process engineering activities such as man-hours for preparing P&ID's, man-hours for preparing process datasheets etc. It is expected that the process engineer will complete the particular activity in the allotted man-hours for that activity. Prior to starting the project, a engineering man-hour estimate is submitted for approval to the client.
After discussion and mutual agreement between the client and engineering consultant the man-hours are agreed for the defined scope of work for the project. Any addition / deviation to the scope of work during the engineering phase of the project needs to be studied and additional man-hours if required need to be obtained for the addition / deviation in the project.