Process reliability

Maintenance of process installation is still a necessity to realise high process reliability. Infrared thermography is becoming more and more an useful tool for predictive maintenance in the process and electrical industry. 

The examples discussed in tliis chapter show a strong synergy between fundamental physical chemistry and device processing metliods. This is expected only to become richer as shrinking dimensions place ever more stringent demands on process reliability. Selecting key aspects of processes for fundamental study in simpler environments will not only enable finer control over processes, but also enable more sophisticated simulations tliat will reduce tire cost and time required for process optimization. 

Two vessels arranged in series, a lead/lag arrangement, will allow the SulfaTreat material to be used more efficiently with no interruption in unit service and greater process reliability. The first vessel, the lead ... 

Choice of operating strategy has a significant effect on substrate conversion, product susceptibility to contamination and process reliability. 

The steroid microsphere systems are probably the most successful drug delivery formulations thus far ba.sed on lactide/glycolide polymers. Several of these products appear to be on track for human and animal applications in the 1990s. The success of these formulations is due to the known safety of the polymer, the reproducibility of the microencapsulation process, reliability in the treatment procedure, and in vivo drug release performance (80). 

Licari, J. J. 2003. Coating Materials for Electronic Applications Polymers, Processes, Reliability, Testing. Noyes Publications, William Andrew Publishing, New York. 

Process components also interact in series. This means that a failure of any single component in the series of components will result in failure of the process. The logical OR function represents this case. For series components the overall process reliability is found by multiplying the reliabilities for the individual components ... 

Automation at its basic level can be expressed simply with the statement that analyses that were traditionally manually performed are now performed mechanically through computer-controlled robotics or workstations. Designers typically have a strong desire to exactly reproduce the manual process. In reality, minor changes to the manual approach must be made in order to make the automated process reliable and efficient. 

Where most utility installations are the lime or limestone processes, it can be seen from Table IV that a very small percentage of industrial installations are of this type. Most of these installations are the once-through sodium carbonate, sodium hydroxide, and double alkali processes. Where the utility installations have been plagued with corrosion, erosion, scaling and fouling problems, the industrial installations, have to date performed much better. A number of systems showed a process reliability of greater than 85%. 

The use of installed spares and rotating equipment out of service for periodic maintenance should reduce the impacts on production rate from failures in equipment. This conclusion assumes that the resulting complexity of piping layout and increased manipulation of piping connections does not negate the goal of assuring process reliability. 

Process Reliability Simulation VIP The process reliability simulation VIP is the use of reliability, availability, and maintainability (RAM) computer simulation modeling of the process and the mechanical reliability of the facility. A principal goal is to optimize the engineering design in terms of life cycle cost, thereby maximizing the project s potential profitability. The objective is to determine the optimum relationships between maximum production rates and design and operational factors. Process reliability simulation is also applied for safety purposes, since it considers the consequences of specific equipment failures and failure modes. 

The process reliability simulation VIP should be initiated in the feasibility phase (FEL-2) to produce a block-level RAM model. Based on the results of that model, a more detailed equipment-level RAM model should be developed starting in the definition phase (FEL-3). 

Dehydro-Tech Corporation (DTC) lists the following advantages of the C-G process reliable easy to operate and install proven in over 80 installations worldwide produces water requiring... 

Recovered sulfur supply predictions depend on explicit assumptions or scenarios concerning the development of specific fuels and the production of sulfide ores. They also depend on a second set of assumptions with respect to sulfur pollution control regulations, the means by which these will be met, and the recursive impact of the controls on the production scenarios. For example, given uncertainties surrounding regenerative flue gas desulfurization (FGD) processes, including the sale of sulfur products and concern over process reliability, utilities have been emphasizing throw-away techniques. As new control standards are implemented the disposal... 

For control of bioremediation processes, reliable monitoring methods are needed. Molecular techniques offer useful tools for monitoring of on-site and in situ bioremediation. 

The ethylene-based, balanced vinyl chloride process, which accounts for nearly all capacity worldwide, has been practiced by a variety of vinyl chloride producers since the mid-1950s. The technology is mature, so that the probability of significant changes is low. New developments in production technology will likely be based on incremental improvements in raw material and energy efficiency, environmental impact, safety, and process reliability. 

The process for drug B has been shown to operate within narrow limits and yield finished dosage forms that are therapeutically equivalent, as measured by standard product release criteria. There is no reason to believe subsequent batches will perform differently as long as all conditions remain static. Despite this generally favorable prognosis, additional work is necessary to provide the assurance of process reliability expected today. 

There remains the unanswered requirement to demonstrate blend uniformity of active ingredients B2. This issue might be addressed by testing the blends of a series of batches until sufficient data are accumulated to consider the process reliable. Hwang et al. have provided some insight into establishing an in-process blend test [15]. The vali-... 

Speicher R, Schneider GA, Drefiler W, Lindemann G, Boder H, Knoblauch V (1999) Reliability of Ceramic Valve Plates for Common Rail Injection Pumps. In Muller G (ed) Ceramic Processing, Reliability, Tribology and Wear, EUROMAT99-Vol 12, Wiley-VCH, Weinheim, p 333... 

An important step forward was achieved with the introduction of double- or multiple-anchor dyes. These can be homo- or heterofunctional (mixed-anchor systems). When dyes are provided with anchors of different reactivity, a wide range of dyeing properties can be realized. At the same time, process reliability and dyefastness are improved. Thus far, combination of the triazine and vinylsulfone anchors has had the best effect. 

For most products, a properly structured PQ protocol will require rigorous acceptance criteria, whether employed concurrently or prospectively. A protocol with vague requirements will provide very little information about a process or system. The application of targeted sampling approach methods in conjunction with 3 x or higher sample sizes will result in the strongest support to process reliability. Concurrent validation can be used... 

FDA prefers prospective approaches because process reliability is established before release to the marketplace. 

N.J. Scenna. Some aspects of fault diagnosis in batch processes. Reliability Engineering and... 

Unsteady-state or dynamic simulation accounts for process transients, from an initial state to a final state. Dynamic models for complex chemical processes typically consist of large systems of ordinary differential equations and algebraic equations. Therefore, dynamic process simulation is computationally intensive. Dynamic simulators typically contain three units (i) thermodynamic and physical properties packages, (ii) unit operation models, (hi) numerical solvers. Dynamic simulation is used for batch process design and development, control strategy development, control system check-out, the optimization of plant operations, process reliability/availability/safety studies, process improvement, process start-up and shutdown. There are countless dynamic process simulators available on the market. One of them has the commercial name Hysis [2.3]. 

Electrodialysis Fouling Temperatur e stability Cost Selectivity Reliability Process reliability and selectivity are adequate for current uses. Improvements could lead to cost reduction, especially in newer applications... 

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