English to Japanese Tech/Engineering Chemistry; Chem Sci/Eng steam boiler

In a refinery, steam utility is one of the most important utilities, which can be used at different temperature ranges. Proper handling of the available steam is an important factor for economic aspects of the plant. Instability in steam header pressures restricts optimum use of resources and it can also create safety issues. Constantly changing demands at various steam pressures challenge proper management and control of existing steam supply capabilities. Some emergency situations, such as boiler trip, add complexity to the above problem. Steam load *shedding* is required due to reduction in steam supply while demand being the same. The choice of steam load shedding location can affect economy of the process. Robust and reliable controller strategy becomes critical in such situations.
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