Abstract: A heat exchanger tube, having at least one twisted baffle therein, each of said twisted baffles extends in the inside of the heat exchanger tube along the axis thereof, said twisted baffles extends as long as at least a part of the entire length of said heat exchanger tube, and said twisted baffles are integrated with the inner surface of said heat exchanger tube. The twisted angle of said twisted baffles is between 100° to 360°. The ratio between the axial length of said heat exchanger tube with the twisted angle 180° of said twisted baffles and the internal diameter of said heat exchanger tube is 2 to 3. The thickness of said twisted baffles is approximated to that of said heat exchanger tube; in every cross section of said heat exchanger tube, the transition zone from the surface of said twisted baffles to the surface of said heat exchanger tube, and vice versa, is in the shape of a concave circular arc.

Abstract: A process for hydrocarbon conversion to prepare lower olefins such as ethylene, propylene, etc., and light aromatics by bringing hydrocarbons into contact with a solid granular catalyst. In order to optimize the reaction conditions and product structure and save the capital and operating costs, a piston flow reactor is used in this process and multiple groups of feed inlets, which allow hydrocarbons with different properties to enter the device from different feed inlets and proceed pyrolysis under different operation conditions, are set on the reactor. This process is usable for individual pyrolysis or co-feed pyrolysis of hydrocarbons from refinery gases, liquid hydrocarbons, to heavy residues.

Abstract: A catalyst for the polymerization of propylene comprising components (A), (B) and (C) is provided. Component (A) is a solid product prepared by dissolving a halide of magnesium in a solvent system consisting of an organic epoxy compound, an organic phosphorus compound and an inert diluent to form a homogeneous solution; mixing the homogeneous solution with a halide of titanium to form a mixture; precipitating a solid from the mixture in the presence of an auxiliary precipitant; treating the solid with a polycarboxylic ester to load the ester on the solid; and treating the ester loaded solid with the halide of titanium and the inert diluent. Component (B) is an organic aluminium compound, and component (C) is an organic silicon compound. The particle size of the catalyst can be adjusted by increasing the amount of the inert diluent at a low ratio of the epoxy compound to the phosphorus compound.

Abstract: The vapor-liquid contacting tower contains multiple trays having multiple openings and multiple rectangular downcomers with multiple bottom openings. At least a pair of directing slots and at least a pair of directing baffles are installed in the liquid receiving zone of the tray and under the bottom openings of a downcomer of the adjacent overlying tray.

Abstract: Disclosed are a catalyst suitable for the conversion of carbon monoxide with steam into carbon dioxide and hydrogen, and a process therewith for said conversion. Said catalyst comprises Co, Ni, Mo and/or W active components, TiO.sub.2 -containing carrier and non-alkali metal element promoter(s). Said process comprises reacting carbon monoxide feed gas containing 0.01% or more of H.sub.2 S by volume with steam in the presence of said catalyst at a temperature between 230 to 500.degree. C. under a pressure between 0 to 10 MPa (absolute) with a relatively high yield, whereby heavy fuel can be used as a source of carbon monoxide feed gas for such a process.