Abstract: A hydrocarbon desulfurization system that circulates fluidizable solid particles through a fluidized bed reactor, a fluidized bed regenerator, and a fluidized bed reducer to thereby provide for substantially continuous desulfurization of a hydrocarbon-containing fluid stream and substantially continuous regeneration of the solid particles. A novel transport system is employed for transporting the solid particles between the reactor, the regenerator, and the reducer. The transport system uses close-coupled vessels and gravity flow between various vessels to minimize equipment cost and particle attrition.

Abstract: In a process for manufacture of a chemical product in which a plurality of individual reactant containing feedstreams are combined to form a mixed feedstream for a reactor, and wherein at least one of the plurality of feedstreams is subject to variations in reactant concentration, and another one of the plurality of feedstreams is essentially stable in reactant concentration, a desired ratio of relative reactant concentrations in the mixed feedstream is maintained by a control system which infers a reactant concentration ratio in the mixed feedstream based on process measurements and feed parameters related to the plurality of feedstock containing streams prior to their being combined. In use, flow rate of the feedstream which is essentially stable in reactant concentration is manipulated to maintain the inferred reactant concentrations in the mixed stream.

Abstract: In a process for manufacture of a chemical product, a reactive hydrocarbon feedstream, which varies in composition of the reactive component, is combined with a compatible but unreactive hydrocarbon feedstream to form a blended hydrocarbon stream which is then combined with a reactive alcohol stream of stable concentration of its reactive component, to form a complete feedstream to the reactor. A desired ratio of relative reactant concentrations in the complete feedstream to the reactor is maintained by a control system which maintains a stable concentration in the blended hydrocarbon stream by manipulating flow rate of the unreactive hydrocarbon feedstream responsive to a concentration measurement in the blended hydrocarbon stream. Flow ratio control is then applied to maintain a desired ratio of reactants in the complete feedstream for the reactor by calculating a flow ratio of the blended hydrocarbon stream to the reactive alcohol feedstream.

Abstract: A process for producing a high purity ether product. This process includes utilizing an additive stream, which preferably contains isobutane, to alter compositions of the overhead and bottoms products of an etherification effluent fractionator so that the alcohol concentration in the overhead product is less than that of the azeotropic composition.

Abstract: In a method and apparatus for measuring the depth of a flowing fluid, and controlling the flow rate of the fluid based upon the depth measurement, the fluid is caused to flow through a conduit, where it is irradiated with a known intensity of light, and the fluid is caused to fall from a horizontally directed exit terminus into a reservoir having a reflective bottom. The fluid serves as a wave guide for the light it received within the conduit, and releases the light within the reservoir. The intensity of light reflected from the bottom of the reservoir and emergent from the fluid is directly proportional to the depth of the fluid in the reservoir, and is measured by a photodetector which transmits a control signal to a valve in the conduit.