Unattended operations

Capability of systems for fully automatic, unattended operation Capability to remove gaseous or vapor contaminants from process streams to extremely low levels... 

High-efficiency expanders and their relatively short payback period made even smaller units economically attractive. These machines have demonstrated a high degree of reliability. Hundreds of units have been in continuous uninterrupted service for many years this has removed the need for backup equipment and has demonstrated that unattended operation is entirely feasible. 

Shell boilers are supplied with controls making them suitable for unattended operation, although the insurance companies to comply with safety recommendations call for certain operations such as blowdown of controls. 

As the boilers are designed for unattended operation, it follows that if a fault occurs and an alarm activated this alarm may need to be duplicated at a secondary location where it will be intercepted and acted upon. 

The basic electrorefining process is now being used on a production scale for the purification of non-specification plutonium metal. The technology is sufficiently well developed to permit 24-hour unattended operation of the electrorefining cells, and the quality of the product metal is highly consistent. This technology is rapidly replacing aqueous chemistry for plutonium metal purification. 

The Benchmate program is started. After unattended operation, the vials are removed from the EasyFill module and placed on the LC/MS/MS autosampler tray for analysis. Each Benchmate Workstation will process up to 50 samples in less than a 24-h period. 

In this experiment, a Tubing Shear History Simulator was coupled with a Reciprocating Capillary Viscometer to simulate the above conditions. Results from the experiment are given in Tables I and II and Figure 3, and were retrieved directly from the project data base. Total Instrument use time for this experiment was 17 hr, of which 16.5 hr were completely unattended operation.. Data analysis, including plotting of figures, required less than five minutes. 

Automatic injectors, which eliminate variations due to the analyst, improving reproducibility, and which can be controlled by computer, are of value where large numbers of samples are to be analysed or unattended operation is required. Samples and standards loaded into racks or turntables can be run in a predetermined sequence and under different operating conditions. Such devices can also be used for single samples to improve injection precision. 

Most instrumental parameters can now be set and monitored continuously under the control of a microprocessor and employing a limited amount of memory. This facilitates the running of repetitive analyses with improved precision (although not necessarily with improved accuracy) and unattended operation which releases the analyst for other duties. An example of the degree of control available in a modern instrument is shown in Figure 13.5. 

Unattended operation possible, loop-sampler option autosampler printer, option inorganic, carbon, purgeable carbon, total carbon and total organic carbon measurements possible... 

Modular installations to match load and increase reliability. Remote/unattended operation. 

Additional advantages of process analyzers are the possibility to automate all or most parts of the analysis to offer the opportunity of a 24/7 unattended operation. On the downside, the level of complexity and upfront effort during the design, implementation and even maintenance stages can be high and require specialized expertise. 

Automatic operation of the metering pump allows repetitive injections with unattended operation. Precise control of the carrier-gas flow ensures stable chromatograms and reproducible timings for collection of samples. Independent column oven and vaporizer temperatures are available up to 300°C and these can be operated with temperature programming or isothermally. The latter option is the most common. 

Clock-time programming loads and runs a method for complete unattended operation. 

Unattended operation of the laboratory robot extends the working day and permits faster sample turnaround. In a manufacturing/quality control environment, faster release of product for shipment can greatly reduce inventory costs. 

The industrial processes for hydrogen production are well established [9, 30, 31], but may not be appropriate for small-scale stationary applications such as residential fuel cells or for unattended operation such as on-site hydrogen generation. These new applications allow for new process designs based on catalyst and engineering improvements [10, 32]. Hence a study of the ATR process has to involve both chemical and engineering aspects. 

The detector was designed for automated and unattended operation and for use by nontechnical personnel. We present performance results for the QitTofMS explosives detection system in Section 11.4. 

Some generalizations can be made about this class of photocatalytic oxidation technologies. Because of the systems unattended operation and readily available parts, operation and maintenance costs for these technologies are very low. In one extended field application, direct operating costs were 1 to 2 per 1000 gal of water treated (D108214, p. 311). 

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