Shutdown for maintenance

Startup following a normal shutdown, a shutdown for maintenance, or an emergency shutdown. 

Though there do not seem to be any generally available technical reports, there are genuine stories of explosions and burn accidents caused by the inadvertent formation and subsequent decomposition of hydrates of hydrocarbons in railway tank cars in the cold climate of Canada. Incidents occurred due to the practice of washing empty tank carr following their use for transporting liquid hydrocarbons. In a cold winter climate, it is possible to form hydrates with small amounts of hydrocarbon residues, which later decompose when the tank car warms up, e.g., when exposed to sunshine. For example, the clathrate hydrate of isobutene (2-methyl-propene, b.p. -6.9" C) needs only 1.12 bar at 273 K to be stable. Precautions were not taken around such nominally clean and empty tankers, and exposure to sparks or naked flames led to flash fires and explosions. While the main content of the tankers was butane, other hydrocarbons were present. In another kind of industrial accident, a worker was killed by H2S gas liberated from H2S hydrate residue in a heavy water production plant, during a shutdown for maintenance. 

In all studies, a normal refuelling outage has been examined. Shutdowns for maintenance or other puiposes have not been considered so far. 

Condenser solvent-locked because valve in reflux return line was closed following shutdown for maintenance 3... 

Fuel handling time in FBR is not governing the duration of shutdown of a plant Therefore, parallel operation of fuel handling machines is not needed (10-12 d/a shutdown for fuel handling, 40-50 d/a shutdown for maintenance)... 

Wet standpipes are typically designed for use by properly trained occupants to protect the people and contents of the building. These systems have a constant supply of water and are smaller in diameter for occupants use. The loss-control representative of the insurance company attempts to ensure, through the insurance contract, all suppression systems are operating at all times or standby substitute arrangements are in place during periods of shutdown for maintenance and repair. 

Warning alarms should be provided to notify employees that a conveyor is about to be started (especially after shutdown for maintenance work). Code words may be sent over mobile telephones. 

Operational life Startup from a normal or controlled shutdown is part of the safety procedure. There may be three types of shutdown plaimed, emergency, and shutdown for maintenance, as indicated in Clause 2.1.1. Each of these has certain safety issues associated with it, so, these types of plant shutdown along with startup from emergency shutdown should be checked. 

The optimization system for timing the proposed shutdowns for maintenance is specially geared to the needs of industrial plants. 

When a reactor is shutdown for maintenance and refueling, some safety systems are switched off or isolated. A great number of operator actions are required under this situation for different purposes. 

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