DD145763A5 - SLAG EXTRACTION ELEMENT FOR USE IN A CARBURETOR WITH DECOMPOSITION - Google Patents

Abstract

The object of the invention is to form the slag stripping element so that it is resistant to erosion, corrosion and thermal attack by the slag and the iron. According to the invention the Schlackenabziehelement consists of a solid casting of a metal with high thermal conductivity, for example copper or a copper alloy, with a metal tube therein for the circulation of the coolant liquid. It has an upper funnel surface over which the withdrawn slag flows. The upper funnel surface tilts down and in and overflows into the purge port. The coolant tube extends through the casting compound and forms a coolant line adjacent to the funnel surface and the surface of the aperture passage, and is 6 to 38 mm apart therefrom. The ends of the coolant tube stand out of the surrounding casting compound and form an inlet and outlet.

Description

Schlackenabziehelement

The invention relates to a Schlackenabziehelement, in particular a Schlackenabziehauslaßelement for use in a coal gasification plant.

In such coal gasification plants, coal or other carbonaceous fuel is charged to the top of a columnar gasification vessel and gasified under high pressure and high temperature by means of oxygen and steam introduced near the fuel bed by tuyeres. The residual ash collects as liquid slag and molten iron in the hearth of the gasifier vessel, from which it is periodically drawn down through a slag discharge outlet or port in the hearth in water in a quenching chamber (commonly called slagging). Normally there is a pool of liquid slag and liquid iron in the hearth constantly, because hot products of combustion are directed upwards by a burner located below the scraper-discharge opening in the draw-off opening, so that the pool of. Slag and iron is maintained in the cooker, wherein the Ab / iiehen liquid slag and liquid iron by switching off or reducing the power Bronner and by reducing the pressure in the Abochreckkammer is initiated and controlled since venting eine'gesteuerte

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tion to the atmosphere through the ventilation system to provide a differential pressure between the quenching chamber and the carburettor vessel takes place.

Examples of such a gas plant with detoxifying be great in GB-PS. 977,122 and The Gas Council Research Communications No. GC 50 and GC112.

The jacket materials of Schlackenabziehelements and the cooker in such a gasifier deslagging are aggr ^c esivor erosion, corrosion and thermal attack by the slag and the iron exposed. The high temperature and agility of the slag and iron during slagging and retention of slag leaves the cladding materials of the slag removal and their immediate vicinity primarily exposed to erosion and thermal attack by the iron. "

Aim of the Erf in d

The object of the invention is to provide a slag removal outlet for such a gasifier which does not wear so rapidly under conditions of high temperatures and iron present in the slag during operation of the gasifier.

It is the object of the invention to provide an improved slag removal system for a gasifier having a discharge.

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- to provide these disadvantages to a lesser extent.

According to an aspect of the present invention, there is provided a slag drawing member for use in a slag coal gasifier consisting of a solid casting compound of a high thermal conductivity metal in which a molded metal pipe for circulating a coolant through the casting cup is located; and with an upper funnel surface (tundish surface), from the gasifier, grain ^ via the - flow-inhibiting slag, and is provided to a central purification opening, wherein the upper funnel surface is inclined downwardly and inwardly and collides with the purification opening, coolant pipe dae its Can maintain shape without appreciable deformation during casting of the surrounding metal mass, and the tube passes through the casting mass and forms a coolant line adjacent to the funnel surface and the area of the orifice passage, and a length of 6.35 to 38.1 mm (0.25 to 1; 5 inches) from this surface with the ends of the tube facing outward from the surrounding cast metal mass and forming an inlet and outlet for the coolant.

The conception, the velocity of the slug flow of the stove container through the Schlackenabziehöffnung and the resistance capacity of Schlackenabziehelements to control himself to erosion depends on critical design factors of the slag tap, to which-among other things, the thermal conductivity of the material used, the shape and geometry of its Metal mass, the size of his

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Portion and the size, length and location of its coolant channel with respect to the surfaces of the slag removal element exposed to the thermal attack belong.

The amount and flow rate of the coolant liquid "are ness also important factors in the execution desSchlackenabzugs because of direct contact with the slag and the burner gases exposed areas of the mass must be effectively cooled acceptable surface temperatures, preferably in the range of 50 C to 400 ⁰ C are able to maintain, whereas it is important on the other hand that no excessive amounts of heat are removed by the slag removal from the stove. Conveniently, flow rates on the order of 6.1 to 9.15 m (20 to 30 ft) / s are best for achieving a constant channel wall temperature in the case.

aiming for a constant in the range of 10 to 20 C

The slag drawing-off element is preferably made of copper or copper and alloyed metal.

The uppermost surface of the slag drawing member (generally called the pouring funnel portion) preferably slopes downwardly and inwardly and meets with the surface of the central opening, which may have exactly round or cylindrical shape, 2;

Funnel can have any cross-sectional profile, z. Semicircular or parabolic, although the cone-shaped form is preferred.

In practical Ein.satzbedingungen the carburetor in which

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the temperature of the slag puddle at 1450 ⁰ C and that of

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Burner gases is about 1500 to 1600 ⁰ C, the top surface or the hopper of the Schlackenabziehele be "mentes on a to 4OO C lying in the range 200 Temporatür, the cylindrical surface of its opening lying on a between 100 and 400 ⁰ C temperature and the lowest Surface of Schlackenabzugo held next to the burner at a lying in the range of 50 to 400 C temperature. , ·

Normally, the manufacture of the liquid paint chill peel in a detassified coal gasifier of the type described involves forming the metal tube into a spiral having an inlet and an outlet, casting a mixture of copper or copper and alloyed metal around the spiral certain shape, so that the inlet and the outlet are connected to one another outside the Gußmasee,

F38S pipe may consist of nickel-chromium or nickel-chromium and alloyed metals, which also have strong corrosion resistance.

In addition, the outer surfaces of the tube may be provided with means for improving the bonding with the cast metal to provide good thermal contact therebetween and reduce the tendency of the cast metal to crack when cooled after casting, especially when different metals are used for casting the pipe and the cast metal are used. According to the invention, the outer surface of the tube is provided with numerous edge ribs z attached in the abutment to improve the connection with the surrounding metal.

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According to another aspect of the invention, an improved coal gasifier with purification is provided. This consists of: a gasification vessel, means for filling coal into the vessel for gasification in the vessel, means for introducing oxygen and steam into the vessel for gasifying the coal therein, a furnace located at the bottom of the vessel, is provided with a purification opening for the removal of the slag from lead burner apparatus below the purification opening drying a stream of hot combustion gases in the Entschlakkungsöf.f upwards so that the slag is held on the hearth in the liquid state, a quench chamber below the Entschlockungsöffnung for receiving slag, which has been withdrawn through the Entschlackungsöffnung, and means for reducing or interrupting the flow of hot combustion gases for the removal of slag by dio Entschlack- ungsöffnung; the improvement being that the purge port is centrally located within the hearth and is substantially configured as a vertical passageway through a removable slag stripper in accordance with the first aspect of the invention. '

The invention will be explained in more detail using an exemplary embodiment. In the attached drawing show:

FIG. 1 shows a schematic longitudinal section of a fixed-bed carburettor with purification, FIG.

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Fig. 2: a section of the removable Schlackenabziehelementes in Fig. 1 and

Fig. 3ί is a partial section of the coiled tube in the Schlackenabziehelement.

In Fig. 1 , the carburetor has a refractory lined pressure gasification chamber 10 into which coal is charged from a baffle 12 and distributed by rotary distributors 1.4. "Oxygen and steam are introduced into the fuel bed (not shown) through tuyeres 16 to gasify the coal to support "in Batrieb of the gasifier, a reservoir or pool of liquid slag and liquid iron on the inclined Hero 18 collects and is periodically a- opening _f dio in a removable, mounted in the oven Schlackenabziehelement 20" in a in a Quench chamber 24, in which it is rapidly quenched in a region of turbulent water leaking from a perforated ring 26, before it is in the form of a dense, fine-grained frit with slightly guided quench water after actuation of a valve 30 in FIG a blocking funnel'28 is discharged. The frit is discharged from the blocking funnel 28 on conveyor belts 32. The water supplied to the quench ring 26 through an inlet 34 © water can partially through di'o outlets 36; 38 may be from the quench chamber 24 and the sluice inhibit hoppers 28 by pump ™ and filter means (not shown).

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The quenching chamber 24 is gas-tightly attached to the bottom of the gasification chamber 10 by inserting a sandwich flange assembly 40. A nozzle-type burner 60 is held together with the slag withdrawal nest 20 by the return flange assembly 40, but is mounted so that it can easily be removed therefrom.

In Fig. 2, the slag stripping member 20 consists of a body 42 of copper or copper and an alloyed metal cast around a spirally wound pipe 44 having an inlet 46 and an outlet 48 for the circulation of cooling water, the bottom of the body is. A TrichtOiflache 50 of Schlackenabziehelomen ™ 20 has truncated cone shape and coincides with the cylindrical surface of a Entschlackungsöffnung 52 _P ends in a peripheral edge 54. The outer edge surface 50 of the body 42 is preferably beveled to allow for easy removal from the hearth 18 of the carburettor. An annular recess 53 is located in the underside of the body 42 for coaxial engagement with an edge projection (not shown) on the sandwich flange member 40.

In a particular example of a slag pull-off element 20, the tortuous tube 44 was made of a nickel-chromium alloy, for example that known under the Inconel 600 intrinsic commercial particle length, which was about 42 inches long Inside was 12.7 mm (0.5 inch) and had an IV thickness of 3.175 mm (0.125 inches). The overall width of the casting 42 was about 323.85 mm (12.75 inches) at a total height of about 114.3 mm (4.5 inches). The diameter of the opening 52 was about 50.8 mm (2 inches), the height about 31.1 mm (1 _t 5 inches), and it goes into the hopper

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surface 50 having approximately an angle of 38 to the vertical; The outer surface of the cast-in length of the coiled tubing 44 is preferably provided with numerous spaced-apart edge ribs 45 (Figure 3) for improving the connection with the cast metal to enhance heat transfer to the coolant and any tendency for fractures of the casting upon cooling to exclude the casting process. The coiled tube 44 is located within the casting 42 so that its turns are at least about and along the faces of the funnel 50 and the aperture 52 and that preferably those turns which bear against the faces 50 are between 6.35 and 38.1 mm (0.25 and 1.5 inches) away from it. The slag removal 20 is made by first placing the tube 44 in a desired spirally wound shape, holding the tube 44 by suitable means in a suitable mold from which the inlet 46 and outlet 48 project, and copper or copper alloy dio form to form the body 42 is poured. By this manufacturing process, a good contact is achieved and thus good heat transfer between dom body 42 and formed by the pipe 44 coolant line.

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Claims (9)

Erfindunqsanspruch A slag stripper for use in a slag charcoal digester characterized by a solid casting mass (42) of high thermal conductivity metal having a metal tube (44) therein for circulating coolant liquid through the casting compound (42) and having an upper one Tundish surface (50) over which slag removed from the gasifier flows and a central purge port (52), wherein the upper funnel surface (50) slopes downwardly and inwardly and into the purge port (52 ), the coolant tube (44) can maintain its shape without appreciable deformation during casting of the surrounding metal mass, the tube (44) extends through the casting compound and forms a coolant line adjacent to the funnel surface (50) and the surface of the aperture passageway (52) and from these surfaces (50; 52) is a piece of 6.35 to 38.1 mm (0.25 to 1.5 inches) away, the ends de s tube (44) outside of the surrounding Gußmetallmasse protrude and a coolant inlet (46) and -auslöß (48) form. '· 2. Slag stripper according to item 1, characterized in that the cast metal mass (42) consists of copper or 'copper and alloyed metal. 3 »slag removal element according to item 1 and item 2, characterized in that the upper funnel surface - 11 - Ii. 1. 1980 'C-I (Xi / 215 279 (50) of Schlackenabziehelementes (20 has truncated cone shape and that the edge surface of the central Entschlackungsöffnung (52) has exactly round cylindrical shape. 4. Schlackenabziohelement according to any one of the preceding points, characterized in that the outer edge surface of Schlackenabziehelementes (20) is chamfered. 5. Schlaekenabziehelement according to one of the preceding points, characterized in that the tube (44) as a spiral of nickel-chromium or nickel-chromium and alloyed? Metalbn is formed. 6. Schlackenabziehelement according to one of the preceding points, characterized in that the outer surface of the tube (44) is provided with numerous, spaced-edge ribs (45) to improve the connection with the surrounding metal » A slagging scrim according to any one of items 3 to 6, characterized in that the total bulk of the cast body (42) ranges from 304.8 to 330.2 mm (12 to 13 inches) at a range of 76, 2 to 127 mm (3 to 5 inches) in total height, and that the Entschlackt- ungsöffnung (52) has a diameter between 38.1 to 63.5 mm (1 ^ 5 and 2.5 inches) and a Height of 24.5 to 49 mm (1 to 2 inches) and in the uppermost truncated cone surface, which has an angle of 30 to 45 to the vertical passes. 'χ. - 12 - 11. 1. 1980 C XQ ^ f / 215 279 Coal gasifier with purification, consisting of a gasification vessel, means for filling coal into the vessel for gasification in the vessel, means for introducing oxygen and steam into the vessel for gasification of the coal therein, a hearth at the bottom of the vessel a deslagging port for drawing the slag therefrom, burner devices of the purification opening to direct a stream of hot combustion products to the purification opening, so that the slag is held on the hearth in the liquid state, a quenching of the purification opening for receiving by the Entschlack slag removal means and means for reducing or stopping the flow of hot combustion gases for slag removal by the discharge furnace, characterized in that the purge port (52) is centrally located in the hearth (18) and as a is carried out in a substantially vertical passage through a removable Schlackenabziehelement (20) according to one of the preceding points. A coal gasifier with purification according to item 8, characterized in that coolant liquid circulates through the coolant tube (44) at such a flow rate during operation of the gasifier that the areas of the casting compound in contact with the slag and the burner gases are maintained at between 50 and 400 ° C become.. 11 .. 1. 1980 ' C ICKf? 215 279 - 13 10. The coal gasifier with purification according to item 9, characterized in that the coolant circulates at such a flow rate that the upper funnel surface (50) at a temperature between 200 and 400 ° C, the cylindrical surface of the opening (52) at oiner temperature of 100 to 400 ⁰ C, and the lowest surface of the slag exhaust next to the burner at a temperature of 50 to 400 ⁰ C are maintained. tem