Abstract:
The refractory lined reaction zone of a free flow vertical gas generator for the production of raw synthesis gas, reducing gas, or fuel gas by the partial oxidation of an ash-containing solid carbonaceous fuel or a high-metal-containing liquid hydrocarbonaceous fuel is preheated and deslagged by first heating the slag and ash layer on the surface of the refractory lining to a temperature in the range of about 1800.degree.-2000.degree. F. by means of an annular-type elongated burner whose downstream tip is located near the upstream roof of the reaction zone. The tip of the burner is then lowered along the central longitudinal axis of the reaction chamber to above the bottom central outlet passage of the reaction chamber, and the slag and ash layer is heated to their melting point, or above. The molten slag at the bottom of the reaction chamber and the flue gas pass out through the bottom central outlet. The burner is then slowly raised vertically to the initial position while simultaneously melting successive portions of the slag and ash layer on the refractory walls. The molten slag flows down the walls and bottom of the reaction chamber and out through the bottom central outlet passage.
Abstract:
Dispersions comprising water and particulate solids i.e. carbon and ash are produced in at least one gas cooling or scrubbing zone by quench cooling or scrubbing the raw gas stream from a partial oxidation gas generator with water. The dispersions are resolved by liquid extraction in a decanting zone to produce a water layer containing carbon, dissolved gas, and ash, and also a separate dispersion comprising carbon, extractant, and water. Solids-free water, liquid extractant and uncondensed gases are then separated from each other in a distillation and separation operation. Water is removed from a separation vessel in said operation and introduced on to a stripping plate of a flash column containing at least one stripping plate. The solids-containing water from the decanting zone is flashed below said stripping plate and a portion is converted into steam. The steam passes up through holes or bubble caps in the stripping plate and is dispersed through the water contained on said plate. If desired, a portion of the water obtained from blowing-down a gas cooler may be flashed to steam below the stripping plate. Unvaporized water falls to the bottom of the column where a vertical weir separates the flash column into two chambers. Solids settle out of the water in the first chamber and clarified water flows over the weir into the second chamber. Overflow water from the bottom stripping plate is discharged below the water-level in the second chamber by way of a downcomer. Reclaimed water is pumped to said gas cooling and scrubbing zones from the second chamber, and waste water containing solids in the first chamber is discharged from the system. The overhead from the flash column is cooled below the dew point and introduced into said separation vessel.
Abstract:
A novel vertical decanter is provided comprising a vertical cylindrical vessel with separate inner and outer coaxial concentric conduits that pass down through the central axial flanged inlet in the upper head of the vessel. The mixture of soot-water dispersion and first liquid organic extractant i.e. naphtha is passed through the inner conduit and is discharged through a first horizontal radial nozzle located below the interface level. Simultaneously, the second liquid organic extractant i.e. liquid organic by-products from an oxo or oxyl process is passed through the annular passage between the inner and outer conduits and is discharged through a second horizontal radial nozzle located above the interface level. Adjusting means are provided to vary the discharge height of the second horizontal radial nozzle, up or down should there be a change in location of the interface level.
Abstract:
A method for starting up a pressurized partial oxidation gas generation system comprising a gas generator and gas purification train without atmospheric pollution. The method comprises isolating and prepressuring the gas purification train to a pressure of at least 50 percent of normal operating pressure, starting the gas generator and autogenously increasing the pressure in the gas generator to the pressure of the gas purification train before establishing communication with the gas purification train to permit flow of gas through the gas purification train. Purified gases discharged from the gas purification train may be burned in a flare without atmospheric pollution.
Abstract:
Dispersions comprising water and particulate solids i.e. carbon and ash are produced in at least one gas cooling or scrubbing zone by quench cooling or scrubbing the raw gas stream from a partial oxidation gas generator with water. The dispersions are resolved by liquid extraction in a decanting zone to produce a water layer containing carbon, dissolved gas, and ash, and also a separate dispersion comprising carbon, extractant, and water. Solids-free water and liquid extractant are then separated from said dispersion in a distillation zone. This water is introduced on to a stripping plate of a flash column along with solids-free recycle condensate from the flash column. The solids-containing water from the decanting zone is flashed below said stripping plate and a portion is converted into steam. The steam passes up through holes or bubble caps in the stripping plate and is dispersed through the water contained on said plate. If desired, a portion of the water obtained from blowing-down a gas cooler may be flashed to steam below the stripping plate. Unvaporized water falls to the bottom of the column. A vertical weir separates the flash column at the bottom into two chambers. Solids settle out of the water in the first chamber and clarified water flows over the weir into the second chamber. Overflow water from the stripping plate is discharged below the water-level in the second chamber by way of a downcomer. Reclaimed water is pumped to said gas cooling and scrubbing zones from the second chamber, and waste water containing solids in the first chamber is discharged from the system.
Abstract:
A continuous process for preventing the build-up of metals from the hydrocarbonaceous fuel feed in a partial oxidation system in which about 80-100 wt. % of the carbon-soot produced is recycled to the gas generator. By the subject process a significantly large portion of the metals and metal compounds i.e. ash in the soot-water feed stream to the decanter become concentrated in the grey water that separates out in the decanter in the carbon recovery section. The concentration of ash suspended in the grey water may be then easily reduced in a solids-liquid separator with or without the addition of a flocculant and prior to recycling a portion of the grey water to the gas quench tank and/or gas scrubber. Further, the ash suspended in the carbon-soot-liquid hydrocarbonaceous fuel stream from the bottom of the liquid organic extractant still may be optionally reduced in another solids-liquid separator prior to recycling a portion of said stream to the gas generator as part of the hydrocarbonaceous reactant fuel feed.
Abstract:
Synthesis gas, fuel gas, or reducing gas is produced by the noncatalytic partial oxidation of a slurry of ash-containing solid carbonaceous fuel in a liquid carrier with a free-oxygen containing gas in the free-flow reaction zone of a refractory lined gas generator at an autogenous temperature in the range of about 2350.degree. F. to 2900.degree. F. so that about 75 to 95 weight percent of the carbon in the fuel feed to the reaction zone is converted into carbon oxides. The hot effluent gas stream from the reaction zone containing entrained particulate carbon, unconverted solid carbonaceous fuel, and molten slag is passed through a free-flow radiant cooler where it is contacted by and provides the heat to vaporize an aqueous solution of catalyst consisting of alkali metal and/or alkaline earth metal compound in water. In the presence of the catalyst, H.sub.2 O and at least a portion of the particulate carbon and the carbon in the unconverted solid carbonaceous fuel are reacted together at a controlled temperature to produce additional H.sub.2 and CO.sub.x. The hot effluent gas stream enters the radiant cooler at a temperature in the range of about 2800.degree. F.-2300.degree. F. and leaves at a temperature in the range of about 1350.degree. F.-1600.degree. F. Further, the molten slag in the effluent gas stream may be fluxed with the alkali metal and/or alkaline earth metal compound to facilitate separation of the slag from the effluent gas stream.
Abstract:
In a high pressure process for the production of synthesis gas from ash-containing fuels where the ash is collected in water in a settling zone below the gasification chamber, bridging by the slag in the narrower sections of the settling zone is avoided by passing a gas upwardly through the settling zone water.
Abstract:
Dispersions comprising water and particulate solids i.e. carbon and ash are produced in at least one gas cooling or scrubbing zone by quench cooling or scrubbing, or both the raw gas stream from a partial oxidation gas generator with water. Advantageously, the water may be reclaimed by the subject process. In one embodiment, the carbon-water dispersion containing any ash is mixed with a liquid organic extractant and a liquid aqueous emulsion. The emulsion breaks up, and in a decanting operation a carbon-extractant-water dispersion containing gaseous impurities separates out and floats on a dilute bottoms water layer containing gaseous impurities and some solids. The carbon-extractant-water dispersion is mixed with a heavy liquid hydrocarbon and introduced into a distillation column. The overhead from the distillation column is cooled and separated in a separation vessel into an upper layer of liquid organic extractant, an intermediate layer of aqueous emulsion, a bottom layer of water, and an overhead stream of uncondensed gaseous impurities if any. The liquid aqueous emulsion and the liquid extractant are recycled to the decanting operation. The water layer from the separation vessel and the bottoms water from the decanting operation are separately introduced into a flash column where the water is reclaimed. The flash column includes at least one stripping plate and two chambers at the bottom separated by a weir. The overhead from the flash column is cooled below the dew point and is introduced into said separation vessel. In another scheme, the emulsion is mixed with the bottoms water from the decanting operation and fed to a flash column for reclaiming water. Alternately, the aqueous emulsion is broken-up into water and liquid hydrocarbon by heating.
Abstract:
An improved continuous partial oxidation process for producing clean synthesis or fuel gas from a hydrocarbonaceous fuel feed is disclosed wherein the effluent gas stream from the reaction zone of the gas generator is simultaneously cooled and cleaned by first discharging the gas stream directly into a relatively large body of hot liquid hydrocarbon immersion fluid contained in an immersion vessel, and second by scrubbing with by-product water obtained subsequently in the process in a nozzle scrubber. The process gas stream is optionally cooled and passed into a gas-liquid separator where any condensed by-product noxious water and any C.sub.5 -C.sub.10 liquid hydrocarbons are separated from each other and from the clean product gas stream. By-product noxious water is disposed of without polluting the environment by recycling a portion of it to the gas generator as the temperature moderator. For example, the immersion fluid may be a dispersion of liquid hydrocarbonaceous fuel such as petroleum oil and particulate carbon which is contained in a separate immersion vessel. A portion of the hot immersion fluid is continuously removed from the immersion vessel and is cooled in an external gas cooler to a temperature in the range of about 300.degree. to 850.degree. F but above the dew point of the water in the process gas stream. Portions of the cooled immersion fluid are recycled to the immersion vessel, and optionally to the gas generator as at least a portion of the hydrocarbonaceous fuel feed. In another embodiment, a portion of the immersion fluid removed from the immersion vessel may be introduced into the gas generator as at least a portion of the feed without first being passed through a cooler. The clean product gas comprises H.sub.2, CO, CO.sub.2, H.sub.2 O and, optionally at least one material from the group H.sub.2 S, COS, N.sub.2, A, and C.sub.1 -C.sub.4 hydrocarbons.