Safe operating components

The steel shell that encloses the refractory is exposed to significant forces from the expansion of the refractory as well as the load from the refractory and the charge within the furnace. Similarly, the stmctures that support the furnace and the foundations must be designed to assure safe operation. A failure of any component can have serious consequences. 

Eail-Safe Design features which provide for the maintenance of safe operating conditions in the event of a malfunction of control devices or an interruption of an energy source (e.g., direction of failure of a control valve on loss of signal). A system is fail-safe if failure of a component, signal, or utility that would create a hazard initiates an action that maintains the system in a safe condition. 

The desirable operating characteristics of equipment include simplicity, convenience and low cost of maintenance simplicity, convenience and low cost of assembly and disassembly convenience in replacing worn or damaged components ability to control during operation and test before permanent installation continuous operation and steady-state processing of materials without excessive noise, vibration or upset conditions a minimum of personnel for its operation and, finally, safe operation. Low maintenance often... 

The Department of Energy Fundamentals Handbook entitled Instrumentation and Control was prepared as an information resource for personnel who are responsible for the operation of the Department s nuclear facilities. A basic understanding of instrumentation and control is necessary for DOE nuclear facility operators, maintenance personnel, and the technical staff to safely operate and maintain the facility and facility support systems. The information in the handbook is presented to provide a foundation for applying engineering concepts to the job. This knowledge will help personnel more fully understand the impact that their actions may have on the safe and reliable operation of facility components and systems. 

Grewer, T., DECHEMA Monograph, 1980, 88(1818-1835), 21-30 One of the principal causes of batch chemical processes becoming unstable is the combination of a high reaction exotherm and a low reaction rate (or rates if there is more than one component reaction in the overall process). A secondary cause of reaction delay leading to instability is too little mass transfer. To permit safe operation of such reaction systems, the reaction energy (which may be expressed as a dimensionless reaction number) and the reaction rate(s) must be known. The possibility of there being a lower safe limit as well an upper safe limit to reaction temperature is discussed. 

Equation 6 Calculation of optimum ratio of particle size and column length, with selectivity factor, a capacity factor of second component of critical pair under analytical chromatography conditions, fe 02 diffusion coefficient, (cm /s) (typical value for MW 1000 10 cm /s) viscosity, p (cP) specific permeability (1.2 X 10 for spherical particles), feo third term of the Knox equation, C and maximum safe operating pressure, Ap, (bar). 

Cutting is a fairly safe operation if the cutters are carefully earthed to prevent them from building up static electricity, which has been a frequent cause of accidents. Care also should be taken to prevent overheating of the cutter component, including the knives. If overheating occurs the cutter must be stopped for some time until the knives are cool. 

Safety engineers and experts are now being asked to conduct the risk assessments required to understand the impact of component and structural failures, uncontrolled radiation or chemical releases, transient operations and unanticipated shutdowns occurring at the chemical or nuclear plant on the safe operation of the other plant. Based on these assessments, control systems and mitigation actions are being developed to minimise the impact of a component or structure failures. Finally,... 

The Safety Section of the SOP is the most vital component, since it deals with the education and protection of those who will run the process. However, it covers more than the dangers addressed in the hazard evaluation phase. It requires the creation of Material Safety Data Sheets (MSDSs) for all the chemicals needed in operating the process. It provides overall guidance on the safe operation of the process and identifies what protective gear to wear and what precautions are needed in the operation. These efforts are also inextricably linked with what needs to be done regarding process emissions and wastes. 

The combined merits of microwave irradiation and ionic liquid make the three-component condensation with safe operation, low pollution, and rapid access to... 

What is the chance of not operating within safe operating limits, and what would be the consequences If operation of the component is critical and a deviation will probably cause a failure, state the corrective actions. If failure is unlikely, keep going. 

Can the properties that govern crack stability and growth be computed on the basis of hrst principles, or must they be determined experimentally How are these properties to be dehned, and how well can they be determined What are the variations in these properties If the failure load or crack growth life of a material can be measured, what degree of certainty can be attached to the prediction of safe operating load or serviceable life of a structural component made from that material ... 

The microreactor design was constrained by the requirement that all electrical and fluidic connections between the microreactor and other system components be implemented using so-called packaging methods that were easy-to-use while maintaining process robustness. The microreactor and any supporting components had to be heated so they could safely operate above the dew points of the feed and product stream compositions, thereby preventing any product condensation from the gas-phase. For these reasons, a simplihed methodology was required that facilitated microreactor removal and replacement. 

Ideally, a solution of a mixture of components applied to a chromatographic column in a small volume would be totally separated and each solute eluted in the same small volume. However, as discussed previously, solute bands broaden as they move down a chromatographic column. For a column of length L we have seen that the broadening increases proportionally to /L whereas the separation of band centres is directionally proportional to L. Consequently, a sufficiently long column will always give a required separation, but in practice the solute will either be too dilute to detect, or the pressure needed to cause flow will be too high to permit safe operation of the equipment. Such problems can be overcome by a careful choice of stationary and mobile phases such that the solutes are selectively retained. The resolution (i s) of two components is a measure of how well they are separated (Fig. 2.5) and is defined by the equation ... 

---