Troubleshooting Chapter

More has been written about plant startup than one might imagine. Since considerable troubleshooting is needed during startup the two subjects tend to overlap. Therefore, the reader is encouraged to seek startup techniques also within the troubleshooting chapter. 

Because printers are such complex peripherals (they re also the reason for the largest percentage of service calls), they are covered pretty extensively on the A+ exam. For the same reasons, we ll skip the details concerning printers in this overall coverage of peripherals and instead devote an entire chapter to printers (Chapter 7). The topic of troubleshooting printer problems is also covered in detail in the chapter on troubleshooting (Chapter 10). 

Printers and their operation are the subject of Chapter 7 (and also about half of the troubleshooting chapter. Chapter 10), so we ll just briefly talk about the different types. There are four major types of printing devices used to get computer output into hard copy (paper copies). They are impact, sprayed-ink, electrophotographic (EP), and plotters. 

While open tubular (OT) columns are the most popular type, both open tubular and packed columns are treated throughout, and their advantages, disadvantages, and applications are contrasted. In addition, special chapters are devoted to each type of column. Chapter 2 introduces the basic instrumentation and Chapter 7 elaborates on detectors. Other chapters cover stationary phases (Chapter 4), qualitative and quantitative analysis (Chapter 8), programmed temperature (Chapter 9), and troubleshooting (Chapter 11). Chapter 10 briefly covers the important special topics of GC-MS, derivatization, chiral analysis, headspace sampling, and solid phase microextraction (SPME) for GC analysis. 

France, John J., Sulzer Chemtech USA Inc., Troubleshooting Distillation Columns, presented to Rio Grande Chapter of AIChE, April 20, 1999. 

John J. France of Sulzer Chemtech USA Inc. provided expert information on troubleshooting distillation columns to the Rio Grand Chapter of AIChE. Checklists were provided for troubleshooting mechanical problems based on considerable successful field experience. This portion of the presentation is presented here with permission. 

A complete discussion of FCC catalysts would fill another book. This chapter provides enough information to select the proper catalyst and to troubleshoot the unit s operation. The key topics discussed are ... 

Catalyst circulation is like blood circulation to the human body. Without proper catalyst circulation, the unit is dead. Troubleshooting circulation problems requires a good understanding of the pressure balance around the reactor-regenerator circuit and the factors affecting catalyst fluidization. The fundamentals of fluidization and catalyst circulation are discussed in Chapter 5. 

This chapter highlights the common problems, symptoms, and probable causes that may be encountered in troubleshooting FCC units. In addition, a systematic approach is outlined to provide solutions and corrective action. The suggested solutions are necessarily generic but apply to a wide variety of units. 

Troubleshooting refers to the solution of short-term problems. The assignment is usually initiated by operations or maintenance. The solution usually involves something that can be done online. Troubleshooting was discussed in Chapter 8. 

The book is divided into four parts. Part I, The Fundamentals of GC/MS, includes practical discussions on GC/MS, interpretation of mass spectra, and quantitative GC/MS. Part II, GC Conditions, Derivatization, and Mass Spectral Interpretation of Specific Compound Types, contains chapters for a variety of compounds, such as acids, amines, and common contaminants. Also included are GC conditions, methods for derivatization, and discussions of mass spectral interpretation with examples. Part III, Ions for Determining Unknown Structures, is a correlation of observed masses and neutral losses with suggested structures as an aid to mass spectral interpretation. Part IV, Appendices, contains procedures for derivatization, tips on GC operation, troubleshooting for GC and MS, and other information which are useful to the GC/MS user. Parts I to III also contain references that either provide additional information on a subject or provide information about subjects not covered in this book. 

Also, a chromatographic profile or fingerprint of trace unknowns can be established and monitored, so that if product performance unexpectedly changes, there will be a starting point for troubleshooting. The effects of experimental variables on sample recoveries should be measured directly by controlled variation of an experimental factor, using the reference standard, or suitable external standards, or spiked addition of an external standard to the reference standard. A detailed example of the use of internal and external standards is presented in Chapter 4. 

Problems that arise with HPLC experiments are usually associated with abnormally high or low pressures, system leaks, worn injectors parts, air bubbles, or blocked in-line filters. Sometimes these manifest themselves on the chromatogram and sometimes they do not. In the following subsections, we address some of the most common problems encountered, pinpoint possible causes, and suggest methods of solving the problems. You can also refer to the troubleshooting guide in Chapter 12 for possible solutions. 

This chapter describes how to be more successful in HPLC operation by summarizing a series of standard operating procedures representing the best practices of experienced HPLC analysts. It offers some brief guidelines on maintenance/troubleshooting and on means of enhancing HPLC assay precision. 

In this chapter, it will be shown how to build the capillary electrophoresis instrument from its components into a robust, functioning analytical instrument. The various components are presented, including a wide range of detection techniques. Some basic troubleshooting along with advice on how to qualify the system is presented along with future prospects for the technique. 

For the pharmaceutical scientist, understanding the theory and application of the equipment is usually not sufficient there is the matter of compliance. The qualification of CE is similar to that of other instruments. Installation qualification (IQ), operational qualification (OQ), and performance qualification (PQ) apply in much the same way as high-performance liquid chromatography (HPEC). This chapter details the different parts of the modern CE instrument, equipment-related issues and troubleshooting, instrument qualification, and the future of the CE instrument. 

Knowledge of the geometry and mathematical description of a screw Is required to understand the analysis of the functional sections of the screw and the troubleshooting of case studies. In Chapter 1 the geometry and mathematical descriptions are presented. Also In this chapter, the calculation of the rotational flow (also known as drag flow) and pressure flow rates for a metering channel Is Introduced. Simple calculation problems are presented and solved so that the reader can understand the value of the calculations. 

The remaining Chapters 9 through 15 are devoted to different types of extrusion troubleshooting analyses. These chapters include presentations on scale-up tech-... 

Three examples are presented that introduce the use of the equations developed in this chapter. These calculations should be used at the start of the performance analysis of all troubleshooting problems. This analysis will be expanded in subsequent chapters through Chapter 7 using additional tools and understandings to complete the troubleshooting process. 

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