Operation Safe Pilot

Chemical reaction hazards must be considered in assessing whether a process can be operated safely on the manufacturing scale. Furthermore, the effect of scale-up is particularly important. A reaction, which is innocuous on the laboratory or pilot plant scale, can be disastrous in a full-scale manufacturing plant. For example, the heat release from a highly exothermic process, such as the reduction of an aromatic nitro compound, can be easily controlled in laboratory glassware. Flowever,... 

Therefore, the fast breeder technology has been developed in different countries on an experimental or pilot-project scale. It has been shown that the fast breeder reactor (FBR) can be operated safely. However, presently it is not attractive economically because sufficient is available to produce nuclear energy at a lower cost. The FBR is certainly an option for the future when other resources become more scarce. 

This chapter may appear to be about aviation, but it is actually about how computerized control systems and plant operators (or pilots) communicate with each other, and the design of the communications interface - the Human Machine Interface or HMl. The examples are taken from aviation because they are well documented they also make clear the crucial role of clarity and reliability in ensuring the pilot-operator can control the plant/plane safely. 

Statement of Phil Boyer, President, Aircraft Owners and Pilots Association Before the Transportation Inifastmctme Subcommittee on Aviation, U/S. House of Representatives concerning Falsified Pilot Medical Certificates, http //www.aopa.org/whatsnew/regulatory/operation-safe-pilothtml. 

Balanced bellows type valves are normally used where the relief valves are piped to a closed flare system and the back-pressure exceeds 10% of the set pressure, where conventional valves can t be used because back-pressure is too high. They are also used in flow lines, multiphase lines, or for ptu affinic or asphaltic crude, where pilot-operated valves can t be used due to possible plugging of the pilot line. An advantage of this type of relief valve is, for corrosive or dirty service, the bellows protects the spring from process fluid. A disadvantage is that the bellows can fatigue, which will allow process fluid to escape through the bonnet. For HjS service, the bonnet vent must be piped to a safe area. 

After any maintenance work involving replacement or adjustment of components it is essential that the plant be re-commissioned in a safe way, including dry mns with the gas turned off to ensure that flame failure devices operate correctly and pilot turndown tests to ensure that if the pilot can energize the flame detector then it can also smoothly ignite the main burner. 

In 1974, after failure and indications of failure of three commercial reprocessing ventures, the AEC reassigned programs for support of commercial fuel reprocessing to emphasize successful experience and lessons learned from that experience. Responsibilities were transferred from the AEC Division of Reactor Development and Oak Ridge National Laboratory with their pilot plant reprocessing model, to the Division of Production and DuPont Company-operated SRP with their safe, successful production-scale reprocessing experience. 

Consider a second example. A surgeon devises a new method of carrying out a surgical procedure and pilots the technique in 10 patients of which none suffer a post-operative infection. Can he claim therefore that the new technique is safe The answer again is no because in this case the upper end of the 95% confidence for the true infection rate is 0-26 % so that infection rate could be as high as one in four. (Hanley and Lippman-Hand developed a simple approximation for the 95% confidence for cases in which the observed data are of the form 0 out of n. They show that approximately the interval is 0-3 / n %. This is known as the rule of three. 

Scale-up from grams to 100 g and more may lead to unexpected problems. Safe operations are essential to minimize risk during scale-up with scale-up there is always increased liability from accidents, including injury to personnel, loss of equipment, delay of key deliveries, damage to a company s reputation, and more. Some companies require that safety hazard assessments be completed before any process is mn in a pilot plant others require safety hazard assessments before a process is scaled up to greater than a given threshold amount. Testing for such assessments may be conducted on... 

The only safe way of designing a rotary dryer is based on pilot plant tests or by comparison with known performance of similar operations. Example 9.5 utilizes pilot plant data for upscaling a dryer. The design of Example 9.6 also is based on residence time and terminal conditions of solid and air established in a pilot plant. 

Hazards attendant on use of ethylene oxide in steriliser chambers arise from difficulties in its subsequent removal by evacuation procedures, owing to its ready absorption or adsorption by the treated material. Even after 2 evacuation cycles the oxide may still be present. Safety is ensured by using the oxide diluted with up to 90% of Freon or carbon dioxide. If high concentrations of oxide are used, an inert gas purge between cycles is essential [7]. The main factors in safe handling and use on laboratory or small pilot plant scales have been identified [8]. Safe operation of ethoxylation processes on industrial scale is discussed, with case histories [15],... 

This solvent was used for synthesis during a campaign in a pilot plant It was known to be contaminated with an alkyl bromide. Thus, it was submitted to chemical and thermal analysis, which defined safe conditions for its recovery, that is, a maximum heating medium temperature of 130 °C for batch distillation under vacuum. These conditions were established to ensure the required quality and safe operation. A second campaign, which was initially planned, was delayed and in the mean time the solvent was stored in drums. 

In a lot of literature, the fail-safe operation of a pilot valve is questionable due to the potential accumulation of dirt, hydrates, and so on, in the pilot supply lines. 

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