Abstract: A process for separating hydrocarbons from an LNG, including the steps of: distilling a feed LNG in a first distillation column to separate it into a fraction enriched with methane and a fraction enriched with components heavier than methane; distilling the fraction enriched with components heavier than methane in a second distillation column to separate it into a fraction enriched with ethane and a fraction enriched with components heavier than ethane; recovering the cryogenic heat of the feed LNG to be fed into the first distillation column or of the liquid inside the first distillation column by using a heat transfer medium; and cooling the overhead gas of the second distillation column by using the heat transfer medium which has recovered the cryogenic heat to condense at least part of the overhead gas of the second distillation column. An apparatus for carrying out this process.

Abstract: A reactor which is a reactor (4) in the form of a cylindrical vessel having a liquid inlet and a liquid outlet and elongated in a flowing direction, comprising, in the interior, a drive shaft (6) coaxial with the reactor, one or more stages of plate-shaped or round-bar-shaped agitating elements (1) extending in a direction perpendicular to the drive shaft, baffles composed of plates or round bars or combination thereof and/or coiled, tubular, plate-shaped or helical heat-exchangers (7) installed on the inner wall side of the reactor, wherein the natural frequency of the agitating elements is greater than the numerical value at which the agitating elements begin to vibrate, the value being calculated from the viscosity of the solution in the reactor, and the rotating speed and structure of the agitating elements.

Abstract: Urea is prepared by reacting ammonia and carbon dioxide in an apparatus comprising a vertical condensation and synthesis column and a stripper, to provide a urea synthesis solution comprising urea, unreacted ammonia, unreacted carbon dioxide and water. The urea synthesis solution is transferred from the top of the vertical condensation and synthesis column to the top of a stripper. Carbon dioxide is introduced into the bottom of the stripper and contacted with the urea synthesis solution, thereby separating the unreacted ammonia and the unreacted carbon dioxide from the urea, and providing a mixed gas comprising ammonia, carbon dioxide and water. The mixed gas is transferred into the bottom of the vertical condensation and synthesis column, where it is reacted with liquid ammonia injected into the bottom and a middle of the vertical condensation and synthesis column. The mixed gas and liquid ammonia are condensed and react to form urea.

Abstract: A reactor including a reactor vessel and heat exchange tubes provided in the reactor vessel. The reactor vessel includes a tubesheet and is configured to receive a reaction fluid. The tubesheet has a first plate member configured to contact the reaction fluid and a second plate member configured to not contact the reaction fluid. Heat exchange tubes are provided in the reactor vessel and fixed to the first plate member. The heat exchange tubes are configured to receive a heat exchange medium. At least a portion of the first plate member configured to contact the reaction fluid is made of a metal that has a high corrosion-resistance against the reaction liquid, and the second plate member is made of a metal that has a low corrosion-resistance against the reaction liquid. The second plate member is detachably fixed to a remainder of the reactor vessel.

Abstract: A method of the gasification of coal using oxygen and steam is provided wherein the coal is gasified at a temperature of from 1000 to 2500° C. and a pressure of from 1 to 100 kg/cm2 using oxygen generated by electrolyzing water and steam having a temperature of from 300 to 600° C. attained by heat exchange heat with a high temperature gas generated by the coal gasification. In the method, a remarkably higher efficiency and low carbon dioxide emission is attained.

Abstract: A device to reform a raw material gas into a synthesis gas rich in hydrogen and carbon monoxide is disclosed. The device includes a vessel, a floating head, a plurality of reaction tubes, inlets and outlets for raw material and heating gases, and a cooled fixed tube plate.

Abstract: An apparatus and process for separating a feed liquefied natural gas containing at least methane and a hydrocarbon less volatile the methane, into a product natural gas enriched with methane and lean in hydrocarbon less volatile than methane and a heavier fraction lean in methane and enriched with hydrocarbon less volatile than methane. The process includes heating the feed liquefied natural gas in a heat exchanger, passing the heated fluid into a distillation column, withdrawing the heavier fraction from a bottom of the column, and withdrawing a residue gas from a top of the column. The process also includes liquefying at least part of the residue gas in the heat exchanger, refluxing a part of the liquid portion of the fluid obtained in the liquefying step into the column, and withdrawing, as the product narutal gas, the remainder of the liquid portion.

Abstract: There are provided a process for separation of hydrocarbons including the steps of: (a) a feed gas is cooled and partly condensed, and separated into a gas and a liquid; (b) the liquid obtained in step (a) is supplied to a distillation column; (c) the gas obtained in step (a) is expanded by an expander and partly condensed, and separated into a gas and a liquid; (d) the liquid obtained in step (c) is supplied to the distillation column; (e) the gas obtained in step (c) is divided into a first portion and a second portion; (f) the first portion is supplied to the distillation column; (g) the second portion is condensed by being compressed and cooled, and then depressurized and supplied as a reflux to the distillation column; and (h) a residue gas is obtained from the top part of the distillation column and a heavier fraction is obtained from the bottom part of the distillation column; and an apparatus therefor. The process and apparatus enable efficient separation of hydrocarbons.

Abstract: A rubber modified polystyrene composition comprising polybutadiene particles dispersed in polystyrene, wherein the polybutadiene particles have an average volume particle diameter of 6 to 13 microns, and the composition has a gel content of 25 to 35% by weight and a degree of swelling of 13 to 22, is prepared by polymerizing the polybutadiene particles in the presence of styrene. The rubber modified polystyrene composition of the present invention may be used for components contacting flon compounds, such as components of refrigerators.

Abstract: A catalyst for the hydrocracking of heavy oils contains iron and active carbon having an MCH conversion rate of 40-80%, a specific surface area of 600-1000 m2/g of, a pore volume of 0.5 to 1.4 cm3/g, 2-50 nanometers' mesopore volume of not less than 60% and an average pore diameter of 3-6 nanometers, the iron being carried on the active carbon in an amount of 1 to 20 wt. % to the active carbon. The hydrocracking process using the catalyst includes a first step of conducting hydrocracking at a temperature within the range of 360-450° C. at a hydrogen partial pressure of 2-14 MPaG and a second step of conducting hydrocracking at a temperature within the range of 400-480° C. at a hydrogen partial pressure of 2-18 MPaG, which can suppress the generation of coke and remove, in a high efficiency, heavy metals such as Ni and V, asphaltene, residual carbon, sulfur and nitrogen from the heavy oils.

Abstract: An oil resistant rubber modified polystyrene composition comprises polybutadiene rubber particles having an average volume particle diameter of 6 to 13 &mgr;m dispersed in polystyrene. The oil resistant rubber modified polystyrene of the present invention has a gel content of 25 to 35% by weight, a degree of swelling of 13 to 22, a residual volatile content of 2000 ppm or less, and a total amount of dimer and trimer of 8000 ppm or less. The oil resistant rubber modified polystyrene composition may be prepared by polymerizing styrene in the presence of polybutadiene rubber, foaming a solution of the rubber modified polystyrene under a reduced pressure of 3 to 40 mm Hg, heating the solution in a tubular heater to a temperature of 190 to 230° C., and then flushing the heated solution into a gas-liquid separator to devolatilize an unreacted monomer and a solvent therefrom.

Abstract: A method for determining a urea concentration in an aqueous solution containing urea, includes: hydrolyzing the urea in the aqueous solution, measuring an electric conductivity &khgr; of the aqueous solution, and determining the urea concentration in the aqueous solution from the electric conductivity &khgr; using a correlation between the urea concentration and an electric conductivity.

Abstract: Stainless steels are welded using a shielding gas including 88 to 98.9 mole % Ar, 1 to 10 mole % H2, and 0.1 to 2.0 mole % CO2. The shielding gas permits low sulfur, high chromium, austenitic stainless steel pipes to be joined with welds having sufficient penetration, strength, corrosion resistance and durability for practical use.

Abstract: The process according to the invention comprises bringing gaseous hydrogen chloride in a non-condensable gas into contact with an absorbing medium selected from water or a dilute aqueous hydrogen chloride solution in an absorption column to cause the medium to absorb the gaseous hydrogen chloride, and subjecting the resultant absorbed solution to distillation in the presence of a salt having a salting-out effect to produce anhydrous hydrogen chloride.

Abstract: Urea is prepared by reacting ammonia and carbon dioxide in an apparatus comprising a vertical condensation and synthesis column and a stripper, to provide a urea synthesis solution comprising urea, unreacted ammonia, unreacted carbon dioxide and water. The urea synthesis solution is transferred from the top of the vertical condensation and synthesis column to the top of a stripper. Carbon dioxide is introduced into the bottom of the stripper and contacted with the urea synthesis solution, thereby separating the unreacted ammonia and the unreacted carbon dioxide from the urea, and providing a mixed gas comprising ammonia, carbon dioxide and water. The mixed gas is transferred into the bottom of the vertical condensation and synthesis column, where it is reacted with liquid ammonia injected into the bottom and a middle of the vertical condensation and synthesis column. The mixed gas and liquid ammonia are condensed and react to form urea.

Abstract: A process for producing a synthesis gas which comprises the steps of mixing a desulfurized light natural gas with steam; pre-heating the mixed gas; carrying out a first reforming reaction at a temperature of 500 to 750° C. under adiabatic conditions by bringing the gas into contact with a catalyst having a specific porosity in which a specific amount of nickel or a platinum group metal is contained as an active component in a carrier composed of CaO and Al2O3 and containing a specific amount of CaO, at least part of CaO forming a compound together with Al2O3, or a catalyst in which a specific amount of nickel is contained in an &agr;-alumina carrier containing 98% by weight or more of aluminum oxide and having a specific porosity; and then carrying out a second reforming reaction in reformer tubes in a heating furnace. The light natural gas may be a gas obtainable by reacting a desulfurized heavy natural gas with steam.

Abstract: Urea is prepared by reacting ammonia and carbon dioxide in an apparatus comprising a vertical condensation and synthesis column and a stripper, to provide a urea synthesis solution comprising urea, unreacted ammonia, unreacted carbon dioxide and water. The urea synthesis solution is transferred from the top of the vertical condensation and synthesis column to the top of a stripper. Carbon dioxide is introduced into the bottom of the stripper and contacted with the urea synthesis solution, thereby separating the unreacted ammonia and the unreacted carbon dioxide from the urea, and providing a mixed gas comprising ammonia, carbon dioxide and water. The mixed gas is transferred into the bottom of the vertical condensation and synthesis column, where it is reacted with liquid ammonia injected into the bottom and a middle of the vertical condensation and synthesis column.

Abstract: In a reactor in which reaction tube(s), cooling tubes, heating tubes or combinations thereof are provided, a method for packing a catalyst comprising a step of packing the catalyst in the space formed between the inner wall of the reactor and the outer walls of the tubes by passing the catalyst through a flexible tube provided in the inside of the reactor and having a means to absorb the impact to the catalyst and thereby feeding the catalyst along the inner wall of the reactor with the falling distance of the catalyst maintained within a certain range and a step of fluidizing the catalyst thus-packed in said space, and a device for effecting the method.

Abstract: The present invention relates to the improvement of a replenishment method of a magnesium-based compound and to the improvement of a double decomposition method, which can be used in a magnesium hydroxide desulfurization method. In the improved replenishment method, the magnesium-based compound is supplemented with water and the ratio of Mg/H2O is adjusted to the total Mg/H2O in the desulfurization system. In the improved double decomposition method, a tank for use is provided with an inner cylinder which partitions the tank into an inner part and an outer part, but does not reach the bottom of the tank, and a part of the slurry drawn through the bottom of the tank is fed to the outer upper position in the tank.

Abstract: A urea synthesis process with improved heat economy, wherein a urea synthesis solution obtained by removing most of the unreacted ammonium carbamate by stripping with carbon dioxide at a pressure approximately equal to a urea synthesis pressure is subjected to a high and low pressure decomposition. The gas mixture obtained from the high-pressure decomposition is condensed in at least two steps.