Instrumentation Analyzer

Molecular Weight EPA Method 3 is used to determine carbon dioxide and oxygen concentrations and dry molecular weight of the stack-gas stream. Depending on the intended use of the data, these values can be obtained with an integrated sample (see Fig. 25-28) or a grab sample (see Fig. 25-29). In addition, the instrumental analyzer... 

The instrumental analyzer procedure, EPA Method 3A, is commonly used for the determination of oxygen and carbon dioxide concentrations in emissions from stationary sources. An integrated continuous gas sample is extracted from the test location and a portion of the sample is conveyed to one or more instrumental analyzers for determination of O9 and CO9 gas concentrations (see Fig. 25-30). The sample gas is conditioned prior to introduction to the gas analyzer by removing particulate matter and moisture. Sampling is conducted at a constant rate for the entire test run. Performance specifications and test procedures are provided in the method to ensure reliable data. 

Quality control elements required by the instrumental analyzer method include analyzer calibration error ( 2 percent of instrument span allowed) verifying the absence of bias introduced by the sampling system (less than 5 percent of span for zero and upscale cah-bration gases) and verification of zero and calibration drift over the test period (less than 3 percent of span of the period of each rim). 

EPA Method 25A is the instrumental analyzer method for determination of total gaseous organic concentration using a flame ionization analyzer. The method apphes to the measurement of total gaseous organic concentration of vapors consisting primarily of alkanes, alkenes, and/or arenes (aromatic hydrocarbons). The concentration is expressed in terms of propane (or other appropriate organic calibration gas) or in terms or carrion. 

A Similar aphical presentation of the spatial distribution of a tracer g is or a real contaminant and thereby to some extent the airflow in the studied area is based on the use of computed tomography and optical remote sens-jt]g I2.M beams are sent out horizontally and reflected back to an IR analytical instrument, analyzing the average concentration of the contaminant along the IR beam. By combining data from several measured tines it is possible ro present data in a similar way to Fig. 12.8. Those methods presuppose access ro an expensive and complicated sampling/data processing system. 

Pilot-plant design specifications should be established only after careful consideration of the experimental program because decisions on the accuracy of instruments, analyzers, and other equipment should be based on the requirements of the experiments planned for the unit. Flexibility and versatility are important but costly when provided unnecessarily or too profusely they can result in a unit that is difficult or impossible to operate successfully. 

Designing a process analyzer does not stop at the enclosure and the internal components. The electronics, the spectrometer and all associated optics must be made to be insensitive to the operating environment. This is particularly important for IR instruments that feature sensitive optics and also high-temperature energy sources. This may be achieved by design, where all components must operate reliably independent of the operating environment of the instrument/analyzer, which can include wide variations in humidity and temperature, and the presence of vibration, over a broad range of frequencies. 

The measurement devices may be classed as continuous or discrete (batch) instruments. The continuous instrument constantly measures some physical or chemical property of the sample and yields an output that is a continuous (smooth) function of time. A discrete, or batch, instrument analyzes a discrete or batch-loaded sample, and information is supplied only in discrete steps. In either case, information on the measured variable is fed back to monitoring or control equipment. Each technique utilizes conventional analytical measurement procedures and must be capable of continuous unattended operation. 

The Method 3A concerns the determination of O2 and CO2 using instrument analyzers. A typical O2 analyzer is shown in Figure 7.45. This method discusses test and calibration procedures. Method 3B is specific to... 

O2 instrument analyzer. (From Bartkal, C. E., Industrial Combustion Pollution and Control, Marcel Dekker, New York, 2004.)... 

The EPA Method 6 provides procedures for measuring sulfur dioxide emissions from stationary sources where the gas sample is extracted from the exhaust stack. Ammonia, water-soluble cations, and fluorides cause interferences with SOx measurements. Method 6A concerns sulfur dioxide, moisture, and carbon dioxide measurements from fossil fuel combustion sources by chemically separating the SO2 and CO2 components, where different reagent chemicals are used. Method 6C discusses the use of instrument analyzers to measure... 

Determination of oxygen and carbon dioxide concentrations in emissions from stationary sources (instrumental analyzer procedure)... 

Determination of nitrogen oxide emissions from stationary sources—alkaline-permanganate/ colorimetric method Determination of nitrogen oxide emissions from stationary sources—alkaUne-permanganate/ion chromatographic method Determination of nitrogen oxide emissions from stationary sources (instrumental analyzer procedure)... 

Multi-channel. These instruments analyze each sample for many different components—in parallel for a discrete analyzer, and sequentially for a continuous-flow analyzer. 

Batch. Batch instruments analyze each sample for a single component at a time, but can be readily changed to analyze other components one at a time. These are also called single-channel analyzers. 

Dedicated. A dedicated instrument analyzes for only a specified component or a limited number of diagnostically related components generally, it is not adaptable to other applications. 

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