Abstract: A method for recovering sensible heat from a thermally decomposed high temperature hydrocarbon gas product in the form of high pressure steam of from 40 to 100 kg/cm.sup.2 has been discovered. This method comprises pre-cooling at first the thermally decomposed gas product of high temperature by mixing said gas product with sprayed low temperature hydrocarbon oil as a quenching oil to a temperature of about 300.degree. to 400.degree. C.; and then passing the mixture through the tubes of a shell-and-tube type heat exchanger so as to transfer the heat of said resulting mixture into a high pressure water flowing through the space of the shell side thereof to recover a high pressure steam, followed by separating the condensed hydrocarbon oil from the mixture to reuse said oil by recirculation.

Abstract: A gas-liquid contacting apparatus for removing sulfur dioxide from a flue gas is provided which comprises a vessel for receiving therein a liquid aqueous absorbent in a continuous phase; gas sparger means having an opening means at one end thereof, the gas sparger means extending vertically from above the surface of the aqueous absorbent liquid and through the surface such that the opening means is positioned below the surface wherein the opening means comprises notch means formed in the side walls of the gas sparger means and an open end of the gas sparger means; air sparger means in the aqueous absorbent, below the gas sparger means; outlet means for the gas after it contacts the aqueous absorbent, the outlet means being located above the level of the aqueous absorbent; reactant inlet means into the vessel; aqueous absorbent inlet means into the vessel; and outlet means for the reaction products and spent aqueous absorbent.

Abstract: This invention relates to a process for selectively recovering vanadium from spent catalysts which were used in hydrodesulufurization, hydrodemetallization, etc. of heavy oils until metals in said heavy oils accumulated thereon. More particularly, it relates to a process for recovering vanadium, and if desired, vanadium along with nickel from spent catalysts in such a way that said spent catalysts are chlorinated with chlorinating agent(s) at a temperature below 600.degree. C. without being subjected to calcination so as to convert almost all the vanadium compounds to vanadium tetrachloride which is recovered in the form of a gas, including the chlorination of nickel compounds of nickel chloride which can also be recovered as such by solvent extraction.

Abstract: This invention relates to a process for desulfurization of exhaust gases wherein the sulfur oxides are efficiently removed in the stabilized form from exhaust gases containing said sulfur oxides and at the same time gypsum of good quality is recovered. More particularly, this invention relates to a process wherein exhaust gases are treated with a slurried solution of gypsum containing a specified organic acid component, sulfuric acid component, and an alkali component at a pH value of 5-3 so that the sulfur oxides in said exhaust gases are absorbed and oxidized to form gypsum which is recovered as a by-product of good quality containing no unreacted lime.

Abstract: A decoking device suitable for use on a reaction vessel for the thermal cracking of heavy petroleum oils, including an assembly mounted on top of the reaction vessel and having a cylinder and a piston slidably and rotatably received in the cylinder, the cylinder and piston defining a scrubbing liquid chamber which is sealed from the outside. A scrubbing liquid is fed through the scrubbing liquid chamber to a main injection pipe to inject the liquid through a multitude of jet nozzles in the main injection pipe against the inner wall surfaces of the reaction vessel, the main injection pipe being connected to the piston for movement therewith.

Abstract: This invention relates to a catalyst for hydrotreatment of hydrocarbons comprising one or more of metals selected from the group consisting of transition metals and metals of group IIb of the periodic table supported on sepiolite. More particularly it relates to a catalyst effective in the selective demetallization treatment of hydrocarbons.

Abstract: This invention relates to a process for continuously converting a heavy oil into an asphaltene-metal-free oil by hydrotreating said heavy oil to crack asphaltenes selectively and remove heavy metals such as vanadium and nickel from said heavy oil simultaneously (hereinafter briefly referred to as "removal of metals"), separating the liquid products into a light fraction of an asphaltene-free and metal-free oil and a heavy fraction of an asphaltene and heavy metal-containing oil (hereinafter referred to as a "heavy fraction"), recovering said light fraction as a product, and recycling said heavy fraction to said hydrotreating step.

Abstract: A process for hydrodesulfurization of heavy hydrocarbon oil containing asphaltenes and heavy metals in large amounts is disclosed. The heavy oil is hydrotreated in a continuous 2-step process. In the first step the heavy oil is subjected to hydrodemetallization and selective cracking of asphaltenes by the use of a catalyst having a unique selectivity therefor. In the second step the effluent from the first step is subjected to hydrodesulfurization to produce desulfurized oils of high grade by the use of a catalyst having a pore volume and pore size distribution particularly adapted for the hydrodesulfurization of the effluent.

Abstract: In a process for the thermal cracking of a heavy hydrocarbon in a cylindrical reactor, a portion of the content material in the reactor is taken out and injected back into the reactor according to a specific procedure to form a "wet wall" or liquid curtain on the inner peripheral wall of the reactor, thereby preventing coking in the reactor. The apparatus includes a radially outwardly extending interior annular recess around an upper portion of the inner wall thereof and forming a part of said inner wall and plural means for tangentially injecting the recycled liquid into said recess.

Abstract: A method for the batch thermal cracking of heavy oils, such as steam blowing for production of binder pitch, employing a reactor having a rotary injection pipe which is rotatable within the reactor. Upon completion of the thermal cracking and withdrawal of the reaction product, the injection pipe ejects preheated raw material under pressure against the interior wall surfaces of the reactor while in rotation to remove coke which has deposited on the reactor walls during the previous cracking operation.

Abstract: A catalyst obtained by admixing red mud with alumina or/and an alumina-containing substance, optionally adjusting the water content of the admixture and/or adding an organic binder to the admixture, kneading and shaping the admixture into pellets having suitable size and shape, and calcining the pellets of 600.degree. C to 1,100.degree. C. The catalyst has a high compression strength and can, when used in the hydrodemetallization of hydrocarbons, achieve a high rate of demetallization and a low yield of low boiling fractions. The rate of demetallization is enhanced when the process is carried out using a hydrogen feed containing hydrogen sulfide.

Abstract: This invention relates to a process for treating the waste gas discharged from a urea prilling tower and an apparatus therefor. More particularly, this invention relates to a process for treating the waste gas discharged from a urea prilling tower and an apparatus therefor, characterized by that a continuous liquid or water film flow (hereinafter called merely a liquid film) of a scrubbing solution and/or an absorption liquid (hereinafter called merely a scrubbing solution) is formed so as to traverse across the whole passage of the waste gas within the scrubbing tower, and when the waste gas passes through such a liquid film the fumy minute particles (hereinafter called fumes) of urea, about 1 micron in size, which are contained in said waste gas, are removed by contacting with the scrubbing solution.

Abstract: A single-vessel apparatus for desulfurization of flue-gas containing gaseous sulfurous acid, in which the flue gas is contacted with an absorption liquid to thereby have the sulfurous acid content in the flue gas absorbed by said absorption liquid and, at the same time, oxidized by an oxygen-containing gas and further fixed, comprising: a gas dispersing plate member; a weir member; said gas dispersing plate member and said weir member forming in the single vessel first and second zones, the first one being a zone in which the flue gas is contacted with and absorbed by the absorption liquid, the second one being a reservoir of the absorption liquid; a flue gas introduction portion for feeding flue gas from below said gas-dispersing plate member to said first zone; a pipe through which to feed a sulfurous acid gas-fixing agent into the vessel; a pipe for discharging the absorption liquid; a treated gas-discharging outlet; a liquid-raising pipe disposed between a lower portion of said second zone and the flue ga

Abstract: A multi layered sound-proofing structure comprises: a first layer comprising a light aggregate and a binder and having a bulk density of from 0.1 to 2.0 g/cm.sup.3 and void fraction as continuous void of from 15 to 60%; a second layer of a material having a quality to insulate relatively high frequency sounds and penetrate relatively low frequency sounds; a third layer comprising a light aggregate and a binder, the same as or different from those of the first layer and having a bulk density of from 0.1 to 2.0 g/cm.sup.3 and void fraction as continuous void of from 15 to 60%, the first and second layers each overlying the third layer; and a fourth layer of a material having a high sound-insulating ability and covering all surfaces of a layered structure of said first, second and third layers except for the sound incident surface of said first layer. A perforated plate may be provided over the sound incident surface of the first layer with an air space therebetween.

Abstract: In a process for the thermal cracking of a heavy hydrocarbon in a cylindrical reactor, a portion of the content material in the reactor is taken out and injected back into the reactor according to a specific procedure to form a "wet wall" or liquid curtain on the inner peripheral wall of the reactor, thereby preventing coking in the reactor.

Abstract: A catalyst obtained by admixing red mud with alumina or/and an alumina-containing substance, optionally adjusting the water content of the admixture and/or adding an organic binder to the admixture, kneading and shaping the admixture into pellets having suitable size and shape, and calcining the pellets at 600.degree. to 1,100.degree. C. The catalyst has a high compression strength and can, when used in the hydrodemetallization of hydrocarbons, achieve a high rate of demetallization and a low yield of low boiling fractions. The rate of demetallization is enhanced when the process is carried out using a hydrogen feed containing hydrogen sulfide.

Abstract: A process for controlling the coke balance as well as the size of coke particles within a fluidized bed in the range adapted for continuous operation of a heavy residual oil cracking apparatus, wherein thermal cracking of heavy residual oil is performed under fluidization of coke particles and steam, which comprises classifying one portion of the coke particles withdrawn from the fluidized bed into coarse particles and fine particles by means of a pneumatic classifier, and after the size of said coarse particles have been reduced by combustion, returning them to the fluidized bed along with said fine particles.

Abstract: A process for the thermal cracking of heavy oils with a fluidized particulate heat carrier is carried out while recovering particles of the heat carrier accompanied by a stream of the reaction product by means of a cyclone and a gravitational separator, returning the particles of the heat carrier recovered by the cyclone directly to the reactor and returning the particles of the heat carrier recovered by the gravitational separator to the reactor in the form of suspension in a cracked oil.

Abstract: Waste gas containing sulfur oxide (SO.sub.x) and nitrogen oxide (NO.sub.x) is mixed with an ozone-containing gas to have the value x of NO.sub.x fall in the range of 1.2 to 2.5 and thereafter brought into contact with an aqueous solution containing sulfuric acid, nitric acid and an iron compound to be deprived of SO.sub.x and NO.sub.x. To the solution with which the waste gas has been brought into contact, air or oxygen is added to effect oxidation of the part of said oxides still remaining therein in an unoxidized state and regenerate the activity of the iron compound functioning as a catalyst. Part of the solution to which the addition of air or oxygen has been made is recycled as the solution for the purpose of contact with waste gas.

Abstract: An earthquake isolating and vibration absorbing equipment for structures is provided with a hanger secured to one of a floor including a ground and a supported member of a structure installed on the floor, a lever, one end of which is swingably mounted on the hanger, a weight member mounted on the other end of the lever, a holder secured to the other one of the floor and supported member, and arms for connecting one end of the lever to the free end portion of the holder. The structure provided with the equipment is less influenced by an earthquake or vibrations under the action of the lever on which there is mounted the weight member having a weight far lighter than that of the structure.