Basic Components and Operations

To operate an HPLC system, the sample is introduced through the injector into the system and is then pushed through the analytical column by the constant pumping of solvent (or mobile phase) from the reservoir through the system (Fig. 2.1). The mobile phase can be delivered in two ways isocrati-cally, that is, at constant composition, or in the form of a gradient, when the composition is varied. Chapter 4 explains how to decide which form to use and also describes injectors in more detail. Additional information about the operation of pumps can be obtained by consulting the references. 

Following its emergence from the other end of the column, the eluent flows through the detector. Detectors operate on various principles. For example, some monitor the ultraviolet, visible, or fluorometric properties of molecules others monitor radioactivity and still others monitor differences in oxidation-reduction potential and refractive index. These detectors are listed in Table 2.1 together with some examples of the specific reactions with which they have been used. 

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The basic components and operation of a spring-loaded pressure-reducing valve. 

The basic components and operating principle of a scintillation detector are illustrated in Fig. 5.26. 

SOFC is classified as an anion fuel cell with negatively charged oxide ion (CF) migrating through the electrolyte. The basic components and operation of an SOFC are depicted in Figure 9.17. 

Troubleshooting the operation of process equipment requires a good understanding of basic components and how the equipment operates. Equipment used in modern manufacturing is run 24 hours a day, 7 days a week, 52 weeks a year. Routine maintenance is performed on this equipment during scheduled maintenance times. 

SOFC is a higher-temperature fuel cell that operates at a temperature range of 800°C-1000°C with a high operating efficiency of 65%. Electrolyte in an SOFC is a solid ceramic-based material like yttrium-stabilized zirconium (YSZ). It can operate with hydrogen fuel as well as with other fuel types such as natural gas, biogas, and coal gas. The basic components and the overall reaction are similar in an SOFC with the exception of the electrochemical reactions at the anode and cathode electrodes. 

In this section, a description of the SOFC is given in terms of its basic principles and operation, different design configurations, components and materials. 

Instrumental Interfaces. The basic objective for any coupling between a gas chromatograph (gc) and a mass spectrometer (ms) is to reduce the atmospheric operating pressure of the gc effluent to the operating pressure in the ms which is about 10 kPa (10 torr). Essential interface features include the capability to transmit the maximum amount of sample from the gc without losses from condensation or active sites promoting decomposition no restrictions or compromises placed on either the ms or the gc with regard to resolution of the components and reliability. The interface should also be mechanically simple and as low in cost as possible. 

The specification must recognize this very important auxiliary part of the compressor. API 614 is a very complete specification and should be used when applicable. When direct use is not applicable, it makes an excellent guide. The seal system in many cases is combined with the lube system. When separate, many of the seal system components are fundamentally the same, with some specifics, such as operating pressure and control, being unique. For those applications where the sealant is other than lubricating oil, the particular fluid will need discussion. The system basic components, on the other hand, will probably be quite similar. General items that must be considered include ... 

Basically the system design consists of the selection of component parts to combine and operate in the most economical manner for the specified conditions. Unfortunately, the specific conditions are not only for the evaporator where the refrigerant is actually used hut include all or part of the following. These conditions are identified whether the system is a separate component selection or a package furnished assembled by a manufacturer. 

The rig selection will dictate the basic layout of the pad. Based on the necessary area needed to support its functions, ancillary equipment may be added in space conservative measures. In addition to the placement of various stationary rig site components, other operations such as logging, trucking and subsequent completion operations must be provided for. The most environmentally sensitive design will impact the least amount of area, and in that it will be the most economic. Potential pad sites and access routes should be laid out on a topographic map prior to the actual survey. At this time, construction costs can be estimated and compared. Figure 4484 shows such a layout. The cost of building a location includes the cost of reclamation such as any remediation. 

The Eastman process breaks down the PET down into basic components that can be separated from dyes, additives and other impurities. At this stage the pilot plant is still a rather small operation that is designed primarily to produce data rather than the product (97). 

Basic Principles of Operation Gas-separation literature often uses nomenclature derived from distillation, a practice that will generally be followed here. L is the molar feed rate, V is the molar permeate rate, R is the molar residue (L — V). Mole fractions of components i, j, in the feed-residue phase will be Xj, Xj. .. and in the permeate phase yi,yj.... Stage cut, 0, is permeate volume/feed volume, or V/L. 

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