Subtitle: Go With What You Know
This article is for the new engineering graduates, but also applies to those with a year or two of industrial experience. Some of this may seem quite obvious, but perhaps some will be useful.
I recently was invited to speak for an hour to the AIChE student group at University of California at Irvine, or UCI. The topic was Engineering Ethics. During the question and answer period afterward, I was asked what was the most unexpected thing I encountered after graduation. My reply was, I did not expect to be so unprepared for the variety and depth of topics in the industrial world. I gave a few examples to illustrate.
My engineering degree is from The University of Texas at Austin, one of the top engineering schools in the country, if not the world. I learned what they taught, but the fact is that the engineering curriculum cannot possibly teach everything one needs to know in only 4 years of study. The amount of knowledge that an engineer should know increases yearly as more and more fields are created (e.g. environmental engineering, bio-engineering, nano-materials) and existing fields are expanded.
What the new engineer should know can be viewed as 1) the fundamentals are key, 2) a vast body of topics exists and should be studied, and 3) time is your ally if used properly.
A brief side-bar on my career start: my first job was as a process engineer in a chlor-alkali plant in a medium-sized chemical company that no longer exists. The plant is still operating, though, after being sold to other companies. For details, the plant was designed and built by Diamond Shamrock Corporation of Cleveland, Ohio, and was known as the Battleground Plant after the nearby San Jacinto Battleground and monument in LaPorte, Texas - just east of Houston. This was a merchant plant, in that the products were sold on the open market and not used internally by the company.
My first problem was understanding what a chlor-alkali plant did, and how it did it. An engineer would do well to understand what his (or her) plant does. Chlorine, caustic, and hydrogen are produced via electrolysis of sodium chloride dissolved in water. I did not recall that electrolytic cells were mentioned in the undergraduate courses I took, not in chemistry, nor in reactor design. It was all foreign to me. At that time (1977), two technologies existed for chlor-alkali plants, diaphragm and mercury cells. The company had both types in its fleet of plants, but the Battleground Plant had the diaphragm cells.
The solution to curing my ignorance of chlor-alkali technology was in two steps: 1) attending the mandatory safety orientation class, and 2) reading in the Perry's Chemical Engineering Handbook. The safety orientation class gave a good overview of the chemical plant, but was mostly concerned with the dangers and toxicity of the various processes and chemicals. The chlor-alkali plant had plenty of dangers and toxicity: deadly DC current at 800 volts and 90,000 amps in the cell room; chlorine gas is toxic and can be deadly; caustic soda even in dilute strength (cell liquor) is hot, corrosive, and can blind the eyes; hydrogen is invisible, auto-ignites, and the flame is a pale blue that is essentially invisible in daytime. The plant also used asbestos in creating the diaphragms. There was also sulfuric acid in one process area, with the acid strength ranging from 70 to 98 percent. There were also the usual dangers in a process plant, steam at various pressures, fuel gas, AC current at various voltages, and rotating machinery, to name just a few.
After gaining an appropriate respect for the hazards I would face on a daily basis, the next task was to read the Perry's, where Electrochemistry was discussed in a few pages. However, the Perry's treatment was mostly theoretical and I was not much wiser for having read the material. I then turned to another favorite, Chemical and Process Technology Encyclopedia by D. M. Considine (McGraw-Hill 1974). This excellent resource had what I needed: about half a dozen pages on chlorine production, including a process flow diagram. (readers should note the time frame, 1978. At the time, there was no internet with vast resources.) Finally, the plant library had design books specific to the Battleground Plant, with process flow diagrams and material balances.
This brings me to point 1) from above, the fundamentals. I finally had a grasp of the fundamentals of electrochemistry and how a chlor-alkali cell operated. In its simplest form, DC current passed through a conductive brine attracts the chlorine ions, Clˉ, to the positive electrode, and the sodium ions, Na+, to the negative electrode. The chlorine ions combine to form a molecule of Cl2, while the sodium ions combine with OHˉ ions to form NaOH. The left-over hydrogen ions combine to form a molecule of H2. From there, the products Cl2, NaOH, and H2 were processed, purified, and condensed (the chlorine) into products for sale or internal use.
The new engineer must, in my opinion, gain a good understanding of the fundamentals of his (or her) assigned process, no matter what that process is. The above outlines the steps I took to gain an understanding. Next, the fundamentals of engineering are key to success. No matter what field or area one is working in, the various laws apply: material balance, heat transfer, mass transfer, equilibrium, fluid flow, etc.
Now to point 2), a vast body of topics exists and should be studied. The list below includes a number of topics that are common to the process industries, both batch processes and continuous processes. Budgeting, Control and Instrumentation, Corrosion, Cost Estimation, Economics (especially incremental economics), Environmental, Equipment, Feed Specifications, HazOps, Laboratory, Maintenance, Metallurgy, Operations, Optimization, People, Pinch Technology, PFD & PIDs, Plant's Design, Project Implementation, Product markets, Product Specifications, RAGAGEP, Regulations, Safety, Technical Plan, and Trade Offs. These are the main issues that a plant process engineer will encounter. Those working in other areas will have different issues to learn. Engineers also work in EPC companies, Engineering/Procurement/Construction, research, catalyst development and production, technical sales, government agencies, and others.
Point 3) from above, time is your ally if used properly. A new engineer could, and should in my opinion, strive to learn as much as possible as quickly as possible about the areas in which he (or she) is deficient. Time for such learning can be found by arriving an hour early to work, at the lunch break, and staying an hour after formal work hours. A study plan can be developed that will encompass the topics. Another way to increase knowledge is regular attendance at AIChE monthly chapter meetings where continuing education credits are given. Many times, these meetings include a presentation or lecture by industry experts on a particular subject. Reading industry literature, including magazines or e-zines is especially helpful.
UPDATE: 6/6/2015 - brief expansion on the additional topics to be studied.
Budgeting - the engineer should know that a process plant has at least one budget, there being typically three or more. These include a) annual operating budget, b) capital budget, c) local spending budget (under the control of the plant manager). Learning what each budget controls, the budget size, and how the budgets are prepared are all vital to understanding the plant's operation.
Control and Instrumentation - many times, the new engineer has had a course in the basics of process control and instrumentation; if not, he or she should study this. The basics include (but certainly are not limited to) the four basic controlled parameters: temperature, flow, level, and pressure (and note there are several others); the measurement instruments that collect the signal; the controller that processes the measurement and sends out the correction signal; the control device (usually a control valve but not always); and the actuator that moves the control device. In addition, the engineer should understand the basics of various control schemes, and why each controller exists at that particular point in the process. Higher (and lower) levels of instrumentation and control exist, including safety and machinery health (bearing temperatures, shaft vibration), DCS (distributed control systems), advanced process control (computerized integration of basic controls with process models including optimization and constraints). Other areas include inferential controls, analyzer-based controls, to name just two.
Corrosion - the measurement and management of corrosion in a process plant is extremely important, even vital. The engineer should read and understand the basics of corrosion - it is simply a rather slow chemical reaction that (typically) removes molecules from the corroded surface and results in thinning (usually) and weakening of the material. The corroded material may be a process vessel, a pipe, or other equipment. Corrosion control and management may include passivating chemicals added to slow down the corrosion rate, upstream removal of corrosive molecules (e.g. sulfur and salts), and temperature control to keep the corrosion rate manageable. Wall thicknesses are measured during periodic shutdowns.
Cost Estimation - the new engineer almost always has some experience in cost estimation in undergraduate studies, but the employer likely has its own cost estimation philosophy and software.
Economics (especially incremental economics) - the new engineer also likely has some experience with economics in undergraduate studies. The process plant likely has various criteria that the engineer is required to use for economic studies, including a list of values (or prices) for each utility, feedstock, intermediate streams, products, and process unit operating costs. Sometimes feeds, intermediates, and products prices are confidential and guarded with great secrecy. Incremental economics must be understood, as these are quite different from average values. It is also crucial to understand that not all energy is equal, as a BTU (or kW) saved in one area may actually have zero value. In addition, the cost to install equipment to save energy, or increase yield, or improve product separations may greatly exceed the benefits. Some plants have a strict guideline that no potential project is to be advanced for consideration that has greater than two years simple payout.
Environmental - the new engineer should learn what environmental issues exist in his or her plant, with the three standard classifications of air, water, and solids. Typically, the plant has one or more permits from state or federal agencies that list the quantity of allowable emissions for each pollutant. Potential modifications to the plant, e.g. adding a new fired heater, may require expensive and time-consuming revisions to the environmental permits.
Equipment - the new engineer likely has a good understanding of the basic equipment types from undergraduate work. The plant likely has equipment that was not included in the classwork, and almost certainly has variations on familiar equipment. As an example, there are many types of pumps (centrifugal, positive displacement) with several variations of each. The same is true for relief valves, control valves, block valves, compressors, heat exchangers, filters, separator vessels, fired heaters, boilers, piping, fittings, turbines, electric motors, reciprocating engines, and many more.
Feed Specifications - each plant, and each unit within a plant, will have one or more feed specifications. The engineer should understand what each specification is, what the allowable limits are, and how that item is measured. Equally important, the engineer should know what the ramifications are when a feed specification is above or below the limit.
HazOps - or hazard and operability study, is an important part of a process plant's safety plan. This should be thoroughly understood by the engineer.
Laboratory - the plant laboratory, the samples, and analytical tests should be understood by the engineer. The plant may have a laboratory on-site, or may send samples to off-site labs for testing. Many laboratory tests are described by an ASTM number (American Society for Testing and Materials), or other designation. Reference books exist that describe each test; these should be on the engineer's bookshelf and be read and understood.
Maintenance - the plant maintenance is one of the three major organizations in a typical plant (the others are Operations, and Technical Services). Maintenance is a vast, complicated, and essential aspect of a process plant's success, safety, and profitability. The engineer should learn the essentials of the plant's maintenance organization and program. Typically, maintenance is organized by craft: millwrights, electrical, instrumentation, and piping. Safe shutdown and isolation procedures must be understood by the engineer, as well as startup procedures once the maintenance is completed.
Metallurgy - the engineer should understand the metallurgy and other non-metallic materials used in the plant. Typically, various metallurgies could be used in a plant, and the choice is made based on several considerations: safety, cost, durability, corrosion, and others.
Operations - plant operations is one of the big three organizational arms in a plant (Maintenance and Technical Services are the other two, typically). The engineer should get to know the operations staff, from the Operations Manager to Unit Supervisors, to shift staff. Typically, the shift staff has a Shift Supervisor, each unit has a Lead Operator (or other title such as Head Operator), and Unit Operators and helpers. The engineer should understand the role of each. Terminology for the various operating positions can vary by industry and by plant. For example, there may be one or more Board Operators and Outside Operators where the Board Operator remains at a computer control console in a central control room, while Outside Operators (as the title suggests) work outside among the equipment.
Optimization - the engineer should learn as much about optimization as possible, including what optimization systems and procedures are in place, and what they accomplish. Optimization is a vast topic. One thing a new engineer should know is that seasoned veterans in the Operations and Technical management are usually distrusting of new optimization schemes - especially the benefits that supposedly derive from the optimizer.
UPDATE: 6/14/2015 - (see link) to my March 1998 article in Hydrocarbon Processing, "WHY A SIMULATION DOES NOT MATCH THE PLANT," in which process plant simulations and optimizations are discussed. An excerpt from the article:
". . . there are many reasons why a process simulation doesn't match the plant. Understanding these reasons can assist in using simulations to maximum advantage.
The reasons simulations do not match the plant may be placed in three main categories:
1) simulation effects or inherent error,
2) sampling and analysis effects or measurement error, and
3) misapplication effects or set-up error."
The article then discusses these three categories. -- end update 6/14/2015
People - people skills are essential to success, not just in engineering but in almost every endeavor. The new engineer would do well to focus on what may be called "human engineering," or practical psychology. This is a vast topic, but crucial to success. Stating one's views in a meeting, learning how and when to disagree without offense, learning how to network effectively, all are important aspects. Dealing with incredibly difficult people is to be expected. One good source for process industry engineers is the "You And Your Job" series of articles in Chemical Engineering magazine (online and archived in libraries).
Pinch Technology - the engineer should understand Pinch Technology, (developed years ago by Bodo Linhoff) and how it applies to process heat transfer and other areas. PT has many articles and publications that the engineer can read for an understanding.
PFDs & PIDs - the engineer likely has a basic understanding of Process Flow Diagrams (PFD) and Piping and Instrumentation Diagrams (PIDs) from undergraduate work. The process plant will have detailed drawings of each, which should be read and studied until the engineer is completely familiar with each figure on the drawings. (Note that PID has a different meaning in the process control context, where it means Proportional, Integral, and Derivative).
Plant's Design - where possible, the engineer should know the basics of the plant's design - the capacity basis, the choices among various technologies, storage and inventory quantities (i.e. number of days' storage for feedstock and for products). Unit constraints are also important.
Project Implementation - the engineer should learn how a project is implemented in the plant, whether a capacity expansion, or other type of project. There may be a separate group for project work, or the engineer may be expected to develop and manage a project. The area of project management is (or can be) complicated, with construction contracts, project schedules, disruption to the existing plant, and many other aspects to consider.
Product Markets - the engineer should understand the market or markets for the plant's products. This could include the historic demand, projected demands, whether his or her plant is a low-cost producer or a marginal producer, and especially: how disruptive technologies could make the plant obsolete. This last point is rather important to chemical engineers.
Product Specifications - similar to the above on feedstock specifications, the engineer should know and understand the specifications on each product. At times, no variations in product specifications are tolerated. In other plants, there may be incentives for higher purity and lower prices for selling a product with lower purity.
RAGAGEP - the engineer should understand RAGAGEP (Recognized And Generally Accepted Good Engineering Practice) and how it applies in the plant. RAGAGEP are "engineering, operation, or maintenance activities based on established codes, standards, published technical reports or recommended practices (RP) or a similar document." They "detail generally approved ways to perform specific engineering, inspection or mechanical integrity activities such as fabricating a vessel, inspecting a storage tank, or servicing a relief valve." (source: OSHA NEP for refineries, 2007)
Sources of RAGAGEP are many. Examples are the API Standards (American Petroleum Institute), ASME Code, CCPS (AIChE's Center for Chemical Process Safety), OSHA, NEC (National Electric Code), NFPA (National Fire Protection Association), and other engineering disciplines such as ASCE (American Society of Civil Engineers).
The intent of RAGAGEP is to ensure that process plants, manufacturing plants, structures, civil works, electrical works, and other things designed and built are as safe as possible. This extends to ongoing repairs and maintenance, alterations and changes, inspection and testing.
Regulations - the engineer should develop at least a basic understanding of the multitude of government regulations that apply to the plant. These likely include (but are not limited to) environmental, OSHA, FTC, labor laws, and others.
Safety - the engineer should understand the basics of the plant's safety program. Safety should be first, as the slogan says (Safety First). Whether the engineer is designing a new process, a modification to an existing process, or reviewing operating procedures, safety is critical.
Technical Plan - the Technical Plan is (or could be) a part of the Technical Services division. The engineer should become familiar with the tasks or projects that are underway or were recently completed, and those that are contemplated for future work. Unless the plant is recently completed and started up, the engineer will find there is a legacy of studies, projects, and reports for each that can be read and studied.
Trade Offs - the engineer should know what trade-off opportunities exist in the plant (this is a subset of the Economics and the Optimization areas above). Trade-offs exist for making or purchasing utilities, feedstocks, and processing or selling intermediate streams.
-- end update 6/6/2015
Roger E. Sowell, Esq.
Marina del Rey, California
copyright (c) 2015 by Roger Sowell
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