Process on-line

In devices with geometry below the 0.25 im level, titanium nitride will likely replace titanium-tungsten, since it has better barrier properties. The process of choice will likely be CVD, which offers improved uniformity and step coverage, although improvements in collimated sputtering may keep that process on line for a while. 

Costs were estimated for treatment of 10,940 tons of soil with an process on-line efficiency of 95% (D11020J, p. 33). Approximately 50 per ton of the total cost was attributed to the SVE system (D11020J, p. 34). The estimate did not include costs associated with analyses, site preparation, permitting, effluent and disposal, or residuals and waste shipping, which were considered site-specific costs (D10505V, p. 6). 

Some instruments are available for process on-line application (Table 6.7). Capillary types give good results with Newtonian fluids and are based upon Poiseuille s law (Volume 1, equation 3.30). The pressure drop across the capillary... 

The reliability of the process measurements1 data is extremely important for good monitoring, control and optimization of chemical process. On-line rectification of a measurement error is possible be it a random error or a gross bias, if additional information is available. Such information is supplied by the extent to which the material and energy balances are satisfied by the recorded data. These balances are simple, involve parameters usually well known, and they should be satisfied independently of the measurements accuracy. 

LDV was operated in the backward scatter mode to obtain simultaneous measurement of two-dimensional velocity components. The resultant signals are transferred to a data acquisition system and processed on-line by a computer. A frequency shifter is employed to measure vertical particle velocity in both directions. As shown in Fig. 9, the LDV measured local particle velocity agree well with those from the optical fiber probe (Yang et al., 1991). 

Ampoules may be sterilised by dry heat or steam autoclaved after filling provided the product will withstand this process. On-line sterilisation often uses dry heat at over 300°C for a controlled period. 

Literature reports on a variety of applications of dielectric measurements in different types of technical processes. The classical application is to determine water contents in process fluids by means of capacitance measurements. This technique has also been extended to higher frequencies by Wasan and coworkers (173, 174). In the following we present a technically very important problem that combines a controlled reaction inside a W/O emulsion and dielee trie Spectroscopy as a process on-line instrumentation. This problem concerns the formation and transport of gas hydrates in pipelines. 

For tub products, a much softer filling consistency is required than for wrapping. Therefore, tub products are processed on lines with a (post)crystallizer instead of a B-unit. The filling consistency can be adjusted by varying the rotational speed of the crystallizer. Precrystallization can be applied in the tub-filling lines as well. 

Since emulsion polymerisation is generally a sensitive process, care must be taken to ensure the consistency of the final product from batch to batch or during a single continuous operation. Furthermore, emulsion polymers are products by process , meaning that the manner in which the polymerisation is carried out is perhaps more important than the raw materials in determining the form of the final product. For this reason, it is desirable to monitor the emulsion polymerisation process on-line (although in practice, many commercial producers measure properties after... 

The production machine yield was 93-96%, this being regarded as highly satisfactory, and after six months operation the unit has proved to be very reliable. It is easy to start up and shut down, and to operate. Pressure drop is <50% of that expected. Height of a transfer unit is 8 cm (4 cm was expected), but this is the same as the pilot plant. Three units were installed, two being adequate for production. There have been no control problems. It took four years from conception to having the process on line. (See also Section 5.4.3 in Chapter 5 for data on rotating packed beds in the context of reactors.)... 

A problem associated especially with multipurpose plants is the possible entry into an operating system of emical materials that are extraneous to the process in operation. For example, a solvent or raw material may be awaiting transfer to later use in another process in the same equipment. If incompatible with any of the materials used or produced in the process on line, the reserved solvent/raw material is a potential hazard unless positive steps are taken to exclude it from the ongoing process. Accidental intermingling is a two-way hazard. It is equally possible that a substance can leak from the process into the extraneous solvent/raw material. Inadvertent mixing can also cause difficulties in maintaining product quality and can present extra hazards to customers. 

After identification of a cosmic spike, another approach to remove the spike is to use a median filter on several related spectra. The spectra can be related in time, for time-series data as with data taken from a process on-line analyzer, or related in space, in the case of a Raman image dataset in which spectra are taken from spatially segregated locations. 

As in all industrial production lines, quality is controlled throughout the glass process on-line or off-line. As in Chapter 10, we shall not review all means for controlling the production but focus on some of them. 

Development of test methods for process (on-line) analysis and validation of these analyses are continuing under the direction of ASTM Committee D02.0D, Section 1 and D02.25. A proposed gas chromatographic/selective detection method is under development for the trace analysis of sulfur com-pKnmds in ethene and propene. 

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