Troubleshooting case history

Figure 1.1 Column troubleshooting case history, (a) Hot oil from the fractionator supplies heat to gas-plant reboilers.

Close to 300 case histories of malfunctioning columns were extracted from the literature and abstracted in Chap. 20. Table 1.1 classifies the malfunctions described in these case histories according to their principal causes. If one assumes that these case histories make up a representative sample (note exclusions and limitations in Chap. 20), then the analysis below has statistical significance. Accordingly, Table 1.1 can provide a useful guide to the factors most likely to cause column malfunctions and can direct troubleshooters toward the most likely problem areas. 

Reproduced from Norman P. Lieberman, Troubleshooting Process Operations (2nd ed., PennWell Books, Tulsa, 1985). This case history is a classic example of how to perform a systematic troubleshooting investigation. The permission of PennWell Books and Norman P. Lieberman for reproducing this material is gratefully acknowledged. 

Obtain a clear, factual definition of the symptoms. A poor definition of symptoms is one of the most common troubleshooting pit-falls. In the debutanizer case history above, the following definitions were used by different people to describe the symptoms of a reboiler tube leak problem ... 

Chapter 4 gives a thorough explanation on how the potential for these problems can be measured, the chemicals used to solve them and several case histories illustrating troubleshooting techniques. 

Since then, the number of products available has grown and become more economically competitive with cationic starch. Since the last edition of this book new chemistry has become available to the industry. Both glyoxylated polyacrylamides and polyvinylamines are now being used. Chapter 7 provides up-to-date information on these and other products as well as case histories and troubleshooting tips. 

In some circumstances, it may be impractical or too expensive for the troubleshooter to visit the site (e.g., a column located on another coptinent). In this case, the troubleshooter must be in direct (i.e., phone) communication with the operating person, who should be entirely familiar with the column, its operation, and its history. The problem definition in this case must be particularly sharp. 

---