Abstract: A method and apparatus for continuously catalytically exothermally reacting propylene with tertiary butyl hydroperoxide in a reaction mixture stream comprising a tertiary butyl alcohol solution of catalyst, reacting propylene, reacting tertiary butyl hydroperoxide, propylene oxide and reaction by-products by thermosyphonically circulating the reaction mixture stream around a thermosyphonic reactor loop; continuously removing heat from the circulating stream in a downflow heat exchange zone in the reactor and continuously passing the circulating stream of reaction mixture through an adiabatic zone such as an upflow reaction zone of progressively increasing temperature while withdrawing or displacing a product stream in an amount sufficient to maintain a predetermined volume of reaction mixture in the reactor and whereby the density of the reaction mixture in the heat exchange zone will be greater than the density of the reaction mixture in the adiabatic zone whereby continuous thermosyphonic circulation can be

Abstract: A method and apparatus for continuously conducting an exothermic chemical reaction between a reactant feedstock such as isobutane and a chemical reactant such as oxygen wherein a circulating stream of the reaction mixture continuously flows up an upstanding draft tube coaxially mounted in a closed upstanding cylindrical reactor and then down the annulus between the cylindrical reactor and the draft tube to establish circulatory motion, and wherein the circulatory motion is thermosyphonically maintained by charging oxygen adjacent the bottom of the draft tube for exothermal reaction with isobutane in the draft tube to thereby heat the upflowing circulating stream, wherein a stream of cold isobutane is continuously introduced adjacent the top of the annulus to cool the circulating stream by direct heat exchange contact, wherein indirect heat exchange cooling coils are provided in the annulus adjacent the top thereof for further cooling the downflowing circulating stream and wherein a discharge line is provided

Abstract: The invention provides an improved method and apparatus for operating a fluidized bed chemical processing unit of the type having steam generating coils, so as to reduce the occurrence of thermally-induced stresses in the coils and thereby extend the useful life of the coils.The invention involves causing the tube wall temperature of a coil being brought into service to be lowered from bed temperature prior to initiating water flow in the coil, so as to decrease the thermal shock temperature gradient and thereby reduce the magnitude of thermally-induced stress in the coil.The invention utilizes a base coil in addition to the steam generating coil that is being cycled, and a pair of steam drums which operate at a pressure differential. The method involves generating saturated steam in the base coil and superheating the saturated steam in the coil being brought on line. Steam is directed from one drum to the other in a predetermined manner so as to provide proper temperature control of the coil being cycled.