Safety high temperature

If Ail increases faster than k, operate at high temperature (but beware of safety and materials-of-construction constraints). 

Thermal power plant components operated at high temperatures (>500°C) and pressures, such as superheater headers, steamline sections and Y-junctions, deserve great attention for both operation safety and plant availability concerns. In particular, during plant operation transients -startups, shutdowns or load transients - the above components may undergo high rates of temperature / pressure variations and, consequently, non-negligible time-dependent stresses which, in turn, may locally destabilize existing cracks and cause the release of acoustic emission. 

With this type of apparatus (Fig. 33) high temperatures can be reached with safety and the dangers of hot oil or concentrated sulphuric acid... 

There are currentiy two principal processes used for the manufacture of monomeric acryhc esters the semicatalytic Reppe process and the propylene oxidation process. The newer propylene oxidation process is preferred because of economy and safety. In this process acroleia [107-02-8] is first formed by the catalytic oxidation of propylene vapor at high temperature ia the preseace of steam. The acroleia is thea oxidi2ed to acryhc acid [79-10-7]. 

Health, Fnvironmental, and Safety Considerationsfor High Temperature OrganicHeat Transfer Systems, Dow Chemical Co., Midland, Mich. 

The Hanford N Reactor. The Hanford N reactor was built in 1964 for purposes of plutonium production during the Cold War. It used graphite as moderator, pierced by over 1000 Zircaloy 2 tubes. These pressure tubes contained slightly enriched uranium fuel cooled by high temperature light water. The reactor also provided 800 MWe to the Washington PubHc Power Supply System. This reactor was shut down in 1992 because of age and concern for safety. The similarity to the Chemobyl-type reactors played a role in the decision. 

Accidents. In an industry that has massive equipment, high temperature operations, and many moving objects, the potential for accidents is always present. Safety is taken seriously and is the direct responsibiUty of the plant superintendent. Accidents do occur, although in the United States the rate in the steel industry compares favorably with heavy industry as a whole. 

Health and safety factors in in situ operations are associated with high temperature, high pressure steam, or high pressure air. Environmental considerations relate to air and water quaUty and surface reclamation. In some environmentally sensitive areas such as the oil sands deposits in Utah, environmental considerations may make development unfeasible. 

High temperature lubrication, as in some metal-forming processes, requites dry graphite. Although the coefficient of friction of graphite is higher than that of petroleum lubricants, it is often added as a safety measure should the carrier lubricant fail (17) (see Lubrication and lubricants). 

Haag, G., Kugeler, K. and Philippen, P.-W., The high temperature reactor (HTR) and the new German safety concept for future nuclear power plants. In Proceedings of the... 

It is important to note safety differences between the SRS reactors and LWRs. Since the SRS reactors are not for power production they operate at a maximum temperature of 90° C and about 200 psi pressure. Thus, there are no concerns with steam blowdown, turbine trip, or other scenarios related to the high temperature and pressure aspects of an LWR. On the of nd, uranium-aluminum alloy fuel clad with aluminum for the SRS reactors melts at a m ver... 

Temperature High Temperature Sensor Temperature Safety High 0 ... 

Fire Heat Dector (Thermal) Temperature Safety High ... 

Pressure can liave a significant impact on safety. Extreme pressures can cause severe metal stress, which can lead to a vessel rupture or explosion. High temperatures, plugged lines, and many other condiUons can cause increased pressure. 

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