| 摘要 |
<p>A method and device for controlling the temperature in fluid bed catalytic reactors operating at high temperature. A controlled and adjustable amount of water is fed to a cooling device consisting of heat exchange tubular elements arranged inside the fluidized bed, the amount of water introduced being such that the water is thoroughly evaporated, the generated steam is superheated under a further heat absorption, at high temperatures, from the fluid bed, and the control of the heat exchange and therefore of the fluid bed temperature is effected by regulating the amount of water fed. The temperature control device of the invention comprises a plurality of heat exchange tubular elements arranged vertically and in parallel relationship and each consisting of a pair of inner and outer coaxial tubes, the outer coaxial tube being closed at its lower end and being connected, at its upper end, with a superheated steam horizontal manifold, the inner coaxial tube ending a short distance above the lower, closed end of the outer coaxial tube and being connected, at its upper end, with a waterfeeding horizontal manifold, whereby a countercurrent flow of the water fed is achieved inside the coaxial tubes; the inner coaxial tube is connected with the water manifold through a nozzle having dimensions such as to cause a pressure drop sufficient to permit an easy regulation of the water flow and a uniform water distribution in all of the tubular elements. The invention permits a perfect, thoroughly automatic thermoregulation with a variability range up to +1.degree.C also for high operating temperatures of the reactor and allows a direct generation of steam at high pressure with an adequate superheating degree.</p> |
