In the simplest case, the products of a distillation process are limited to an overhead distillate and a bottoms, whose compositions. Atmospheric distillation summary condenser partial condenser if no stabilizer column. In simple distillation, a mixture of liquids is heated to the temperature at which one of its components will boil, then the vapor from the hot mixture is collected and recondensed into liquid. Total condenser if stabilizer column to remove light ends. Distillation column selection, sizing and troubleshooting, kolmetz handbook of process equipment design june 20 project. Distillation column troubleshooting practical distillation. Find out what had been observed the last time various pieces of equipment had been opened. Distillation principles chemical engineering, 200711, rvce.
The objectives of the unit include rejection of major contaminants and an initial cut of the crude oil into streams for further processing. The column condenses the naphtha fraction and sends a portion of the liquid naphtha, as reflux, to the column to achieve a good separation of the distillate products drawn from the side of the distillation column, such as kerosene, lgo, and hgo, as seen in the diagram. Read download distillation troubleshooting pdf pdf download. Distillation equipment was developed to separate ethanol from the byproducts of fermentation. Employee training and development will unlock the companies profitability and reliability. A fractionating distillation column is used to make this process more efficient. In the first article of this series, jim discussed the importance and challenges associated with distillation control and the control relevant issues of distillation operations. Understanding ejector systems necessary to troubleshoot. Introduction to column distillation distillation is the most common separation technique in chemical process industry, accounting for 9095% of the separation operations this is why more than a half of this course is devoted to distillation or column distillation, which includes binarymixture distillation. He is also the author of the textbook, distillation troubleshooting, published by wiley.
The successful identification of column operating problems becomes critical when the resolution includes modification to distillation tower internals that can only be executed. Distillation in practice, refining, petrochemicals, palm oil and specialty chemicals designing columns for fouling service designing columns for improved operations and maintenance troubleshooting guidelines tower scanning troubleshooting case examples practical sessions using pilot scale distillation column at. This resulted with nonideal behavior prediction for this ideal pair. The disadvantages of simple distillation sciencing. The di erent control loops involved in the automatic control system are presented. The rosemount 3051s ers system eliminates mechanical worries and delivers digital results. Our engineers have extensive experience in column instrumentation and controls. Distillation operation, control, design and troubleshooting course for maintenance personnel introduction the success of every company depends of each employees understanding of the businesss key components. The first book of its kind on the distillation industry, the practical lessons it offers are a must for those seeking the elusive path to troublefree distillation. Pdf troubleshooting in distillation columns gerard. Gammaray scanning for troubleshooting, optimisation and. The old adage prevention is better than cure applies to the design of all process equipment.
Distillation troubleshooting covers over 1,200 case histories of problems, diagnoses, solutions, and key lessons. In this technique, a sealed radiation source and detector move along an equipment, and the intensity readouts generate a density profile of the equipment. Operate, control and troubleshoot distillation column in a professional manner apply and gain an indepth knowledge on distillation technology identify the different distillation methods and implement distillation process involving the normal operation of bubble plate, vapor velocity and velocity distribution. A liquid feed containing the mixture of two or more liquids enters the column at one or more points. Excessive subcooling of a reflux feed to a distillation column can lead to a variety of operational problems. Troubleshooting distillation columns unexpected causes for malfunctioning columns mario roza, markus duss sulzer chemtech ltd, winterthur, switzerland mario.
Figure 1 illustrates the results of a field test in. Distillation troubleshooting collects invaluable handson experiences acquired in dealing with distillation and absorption malfunctions, making them readily accessible for those engaged in solving todays problems and avoiding tomorrows. The hydrocarbon liquid from the lp column is pumped by pump p1 to an intermediate pressure, and vaporized in the exchangers e2 and e1. Distinguishing features of the technology capable of nondisru ptive and noninvasive investigation. A single column can be used to separate several products using the multifraction operation of batch distillation presented in figure 5. Understanding ejector systems necessary to troubleshoot vacuum distillation james r. The surface area for mass transfer is provided by the bubbles and droplets generated by the injection of the vapor into the crossflowing liquid. Cryogenic distillation an overview sciencedirect topics. Methods, operational and design issues find, read and cite all the research you need on researchgate. Trouble shooting distillation columns practical distillation. The peak shape was a secondary issue resolved by flushing the column. Liquid and vapor flows are not altogether countercurrent in a trayed distillation column.
Troubleshooting operating problems is a daily part of the job description for a refinery process engineer, especially when charge rate to the refinery is inhibited. Distillation pressure control troubleshooting the hidden pitfalls of overdesign 535 design operating pressure. The control of distillation columns is a field in its own right, but thats another story. Four recent publications summarized below, provide useful additional material.
See the picture below to better understand how columns work. This, in turn, increases the liquid traffic in the affected area of the column figure 1. Gamma scanning is a nuclear inspection technique used to troubleshoot industrial equipments in refineries and petrochemicals plants around the world. A check revealed that the internal drawings did not indicate how the top orificepan liquid distributor was to be attached to its support ring. Pdf distillation column troubleshooting with improved.
Distillation column selection, sizing and troubleshooting, kolmetz handbook of process equipment design. Chapter 1 troubleshooting distillation simulation continueds case reference plant column brie description soms fe morals 149 91 acetoneda of limited data incorrectly accounted a commercial simulatio n regressio for dimerization of acetone to daa. The simplicity of this technique has made it popular in many countries. There are many books that discuss distillation, but there is only one that concentrates on giving readers practical guidelines for operation, troubleshooting and. A complete understanding of ejector system performance characteristics can reduce the time and expense associated with troubleshooting poor crude vacuum distillation unit cvdu performance. This process is fast and relatively straightforward, but there are many kinds of mixtures that cannot be separated this way. Batch and continuous columns one way of classifying distillation column type is to look at how they are operated. Troubleshooting types of distillation columns there are many types of distillation columns, each designed to perform specific types of separations, and each design differs in terms of complexity. Hplc column troubleshooting what every hplc user should. Kister, available at book depository with free delivery worldwide. Old video on distillation column operation and trouble shooting but the principles still apply today in the 21st. This distillation occurs in the refinery crude unit. Po box 10105 college station, tx 778420105 timothy m.
Troubleshooting distillation columns unexpected causes for. From the original batch stills, distillation equipment has progress to the type of trayed and packed columns used today. Here he continues the discussion by presenting the major disturbances affecting composition control and the importance of properly functioning regulatory controls. Henry kister has conducted over 500 practical distillation technology programs for major corporations in the u. The surface area for mass transfer is provided by the bubbles and droplets generated by the injection of the. Excessive subcooling of a reflux feed condenses some of the internal vapor traffic. Assessing the symptoms a sick distillation system is like a sick person. The distillation column is made up of a series of stacked plates. The operating pressure of a distillation column is one of the main handles with which to control and optimise separation as it affects most other parameters as well as the overall stability of the column. Distillation troubleshooting database of published case. The operation, control and troubleshooting of a distillation column and its associated equipment an overview of distillation, practical solutions as well as theory an understating of essential distillation concepts valuable practical insights for trouble free design and. Although stable operation was achieved at this pressure, concerns were raised that the column might be hydraulically limited at design capacity. For distillation column, correlating the changes in density seen in the scan profile with column internals and what is known from column service records yields an accurate picture of the units performance and physical condition. And then there was one full documentary official duration.
Impulse lines can be unreliable, and long lengths of capillary are hard to work with. Distillation columns by american petroleum institute. General distillation equipment design the first step in resolving any distillation problem is to understand the operating and technical fundamentals of the column. Distillation column flooding diagnostics with intelligent. Distillation operation by henry z kister a good reference book for distillation chapter 1 distillation troubleshooting chapter 10 column.
Today columns range from absorbers, extractors, strippers, and rectifying towers. Chapter 1 troubleshooting distillation simulations continued case references plantcolumn brief description some morals 4 5 1. Column agingequilibration causes retentionselectivity changes 1 2 column 1 after cleaning with 1% h3po4 the primary analyte was sensitive to mobile phase aging of the column. Providing coverage of design principles for distillation processes, this text contains a presentation of process and equipment design procedures. The rosemount 3051s pressure transmitter with advanced diagnostics can be used to detect incipient flooding in real time, and provide an early warning. It is therefore one of the most important parameters to control. Understanding the fundamentals of crude unit operation is critical to effective design, modification, operation and troubleshooting refinery crude units. The majority of distillation column designs meet their defined requirements, the designer having assessed and made suitable allowances for uncertainties. Background the last halfcentury of research on distillation has tremendously improved our understanding and our. Part 1 technique and tools the basic troubleshooting technique.
118 93 367 420 141 435 554 278 1560 1545 1332 299 83 848 1340 1232 150 1479 21 599 1416 485 136 817 575 447 131 1347 838 1180 204 518 1491 465