Arch-Fired Systems

One of the most effective reformer modifications is to use heat from the convection section to preheat radiant section feed. This will reduce radiant section duty and firing rate. The effectiveness of this option is limited only by the risk of coking in the preheat coil, the metallurgy of the preheat coil and the metallurgy of the radiant inlet system. This option has been used to increase capacity by 10% without increasing the arch temperature in the radiant section86. 

Baroreceptors monitor the pressure in the carotid sinuses, the aortic arch, and other large systemic arteries and increase their firing rate when the pressure increases. Their response is nonlinear and depends on whether they are exposed to mean pressure only, pulsatile pressure only, or a combination of both. Katona et al. [1967] developed a model of baroreceptor feedback that has become the basis for many CV neural control models. The output of the baroreceptor model is often passed through a low pass filter representing the CNS and then mapped back to changes in heart rate, contractility, vascular resistances, and vascular unstressed volumes through the sympathetic and parasympathetic nervous systems (Figure 10.8), for example, see Yu et al. [1990]. 

English Kiln. A transverse-arch chamber kiln with a system of flues and dampers above the chambers permitting any two chambers to be connected. It was designed by A. Adams in 1899 for the firing of building bricks made from highly bituminous clays. 

Manchester Kiln. A type of longitudinal-arch kiln that was introduced in the Manchester district of England for the firing of building bricks. It is top-fired. A distinctive feature is the flue system, with horizontal damper-plates, in the outside wall. The Manchester kiln usually has a hot-air system. 

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