DE9208606U1 - Axial cyclone combustion reactor - Google Patents

Description

L. & C. Steinmüller GmbH 5270 Gummersbach, 25.06.1992 P.O. Box 10 08 55/65 GM 9201

Approx./HP

Description Axial cyclone combustion reactor

The invention relates to an axial cyclone combustion reactor for burning solid fuels in a rotary flow field with a substantially conical lower part and a cylindrical upper part, an ash discharge opening at the lower end of the lower part and a central exhaust gas discharge opening in the ceiling of the upper part, as well as at least one fuel supply and at least one air supply.

Such an axial cyclone combustion reactor is known from DD 234 585 A3, in which both a carrier air-fuel mixture is introduced via a swirl generator and combustion air is introduced axially via a swirl generator into the lower end of the conical lower part. The two swirl generators represent complicated components, and in particular the swirl generator, via which the fuel-air mixture is introduced into the combustion reactor, is subject to increased wear.

It is the object of the present invention to create a combustion reactor of the generic type, in which no separate swirl generators are required.

This task is solved by providing at least one tangential air supply.

According to the invention, the rotary flow field is created by the tangential air supply.

In this case, at least one tangential air supply is preferably provided on the cylindrical upper part and at least one tangential air supply is provided on the lower end of the conical lower part. In particular, the air supply on the cylindrical upper part can take place in several stages via air supplies arranged at a distance axially and/or in the circumferential direction.

In some circumstances it may be advisable to provide at least one axial air supply in addition to a tangential air supply, preferably in the form of a nozzle base for the supply of fluidizing air.

From DD 257 280 Al, the supply of fluidizing air at the lower end of the conical lower part by means of a truncated cone-shaped nozzle base is known per se.

While in the DD 234 585 A3 the fuel is supplied via the lower end of the cone, and in the DD 257 280 Al the fuel is supplied via the cone itself, according to the present invention it is preferred that the fuel is supplied into the cylindrical upper part and, more preferably, tangentially. The fuel can also be supplied in several stages in the axial and/or circumferential direction.

In order to be able to cool the conical lower part easily, it is preferably surrounded by an air box from which air enters the conical lower part.

It is further preferred that a double jacket is provided in the air box at a distance from the outer surface of the conical lower part. The cooling air is forced to flow through the annular space of the double jacket.

⁴ V .

It also appears to be useful if at least the cylindrical upper part is bricked up. In addition to the bricking up, an external single or multi-layer insulation can be provided. The insulation can be constructed using an insulating material and/or a forced-flow cooling jacket, whereby the cooling jacket can be arranged inside or outside the insulating material.

In order to improve combustion, it may be advisable to install an afterburning chamber with a larger diameter than the outlet opening and with a lateral exhaust gas outlet downstream of the outlet opening.

The combustion chamber of the reactor is used to burn off the coarse grain up to a limit grain diameter of the cyclone flow. In the afterburning chamber, further turbulence causes further burn-off of the undersize grain and the CO strands emerging from the combustion chamber.

The afterburning chamber can be arranged as a separate assembly on the reactor. However, it is also possible to make a recess in the combustion chamber cross-section in the reactor, so that the combustion chamber itself is divided into a main and an afterburning chamber by the recess.

The axial cyclone combustion reactor according to the invention will now be explained in more detail in various embodiments using the attached figures. They show:

FIG. 1 a reactor with tangential supply of secondary air and multi-stage tangential supply of fuel,

FIG. 2 a multi-stage tangential supply of primary air and a multi-stage tangential supply of secondary air into the cylindrical area, wherein the conical lower part is surrounded by an air box and

FIG. 3 a combustion reactor with tangential supply of primary air to the cone, a cooling jacket for the cone and a multi-stage supply of secondary air, as well as an afterburning chamber arranged on the ceiling of the combustion reactor.

In the combustion reactor 1 according to FIG. 1, both the conical lower part 2 and the cylindrical upper part 3 are delimited by a cylindrical lining. In the description and in the claims, "lining" is understood to mean a lining made up of individual building blocks, a cast lining or a ceramic lining of the reactor interior, e.g. in the form of a stamped membrane wall. Fuel is introduced into the reactor via tangential and inclined fuel feeds 4a, 4b and 4c. Primary air is blown into the cone 2 via lines 5a and 5b opening towards the cone 2. The cone 2 is connected at its lower end to an ash extraction line 6. Classifying air can be blown into the ash line 6 via line 7. The classifying air determines the grain fraction that can be extracted via line 6. Secondary air is supplied tangentially to the cylindrical upper part 3 via a line 8. Ignition gas can be introduced into the line 6 via a valve 9, which is ignited via an electrical igniter 10. The outlet opening 3a assigned to the upper part 3 opens into an angled exhaust gas duct 11. The primary air inlets 5a and 5b are also arranged so that the primary air enters the cone tangentially.

The angled routing of channel 11 reduces the swirl still present in the outlet opening 3a, so that the transport of the fly ash that is also removed in the subsequent discharge line (not shown) takes place essentially without swirl. Such an angled line also essentially prevents backflow into the reactor.

In the embodiment shown in FIG. 2, the reactor 12 is provided in its cylindrical upper part 13 with a lining 14 made up of two layers 14a and 14b, while the conical lower part 15 is assigned an air box 16. The conical lower part 15 consists of a first cone 15a adjoining the upper part 13, a cylindrical intermediate section 15b and a further cone 15c. Such an arrangement is also considered to be essentially conical in the description and in the claims. The air box 16 is provided with a connecting piece 17 into which cooling air flows. This cooling air enters the reactor interior through tangentially aligned openings 18 in the conical section 15a. Furthermore, the cylindrical section 15b is assigned a plurality of

Primary air connection nozzles 19a and 19b are assigned, from which primary air enters tangentially into the interior of the reactor.

The secondary air is supplied via air inlets 20a to 20f arranged at a distance in the axial and circumferential direction. The fuel is introduced at 21. Furthermore, an external cooling jacket 22 is provided, which is supplied with cooling air, to which cooling air is supplied via nozzle 22a and from which cooling air is extracted via nozzle 22b.

Here too, the coarse ash outlet 23 following the lower cone section 15c is provided with a sifting air connection 24.

In the reactor 25 shown in FIG. 3, the cylindrical upper part 26 is again provided with a lining 27 and the conical lower part 28 is arranged in an air box 29, to which primary air is supplied via a connection piece 30, which can enter tangentially into a straight cylindrical section 28a of the conical lower part via an air supply 31. The purely conical section 28b is provided with a double jacket 28b' arranged at a distance. Cooling air enters the space between the conical section 28b and the double jacket 28' via a connection 32 passing through the air box 29, which also enters the air box at the lower end of the double jacket through an annular gap 33.

The pressure on the lines 30 and 32 is regulated and separately, so that the temperature of the air introduced into the cone 28 can be regulated.

A nozzle base 34 is assigned to the lower end of the cylindrical section 28a, through which air from the air box 29 enters the conical lower part 28 as fluidizing air. To remove the ash, an exhaust pipe 35 is provided which passes through the nozzle base and opens towards the cylindrical section 28b.

Secondary air is supplied tangentially to the cylindrical section 26 via secondary air inlets 36a and 36b, while fuel is supplied via line 37. In the upper part of the reactor, a closable passage 38 is provided for an ignition burner (not shown in FIG. 3) that can be pushed into and withdrawn from the reactor chamber. Such a passage 38 is also provided in FIG. 2.

The outlet opening 39 is followed by an afterburning chamber 40 of larger diameter, possibly insulated according to the dot-dash line, from which the exhaust gas

through a lateral exhaust pipe 41. The afterburning chamber 40 extends the residence time of the fuel grains in the system and also at least partially removes the swirl from the flow.

The lining 27 can be constructed in multiple layers, as in the embodiment according to FIG. 2. The material for creating the cone can be high-temperature-resistant steel in all embodiments. In the embodiment according to FIG. 2, the cooling air used for cooling can also be used as preheated primary and/or secondary air.

In addition to the fuel, inert material can be used to stabilize combustion and for continuous cleaning in all three designs. The inert material should have essentially the same properties as the fuel, ζ, β, specific weight, bulk density and/or grain size.

(Here are 3 sheets of drawings)

Claims (13)

L. & C. Steinmüller GmbH 5270 Gummersbach, 25.06.1992 PO Box 10 08 55/65 GM 9201 Ca./HP. Protection claims 1.) Axial cyclone combustion reactor for burning solid fuels in a rotary flow field with a substantially conical lower part and a cylindrical upper part, an ash discharge opening at the lower end of the lower part and a central exhaust gas discharge opening in the ceiling of the upper part, as well as at least one fuel supply and at least one air supply, characterized in that at least one tangential air supply (8; 20a-20d; 36a-36b) is provided. 2.) Reactor according to claim 1, characterized in that at least one tangential air supply (8; 20a-20d; 36a-36b) is provided on the cylindrical upper part (3; 13; 26) and at least one tangential air supply (5a, 5b; 19a; 19b; 31) is provided on the lower end of the conical lower part (2; 15; 28). 3.) Reactor according to claim 1 or 2, characterized in that the air supply to the cylindrical upper part takes place in several stages via air inlets (20a-20f; 36a-36b) arranged at a distance axially and/or in the circumferential direction. 4.) Reactor according to at least one of claims 1 to 3, characterized in that in addition to a tangential air supply, at least one axial air supply (34), preferably in the form of a nozzle base for the supply of fluidizing air, is provided. 5.) Reactor according to at least one of claims 1 to 4, characterized in that the fuel supply (4a-4c; 21; 37) takes place in the cylindrical upper part (3; 13; 26). 6.) Reactor according to at least one of claims 1 to 5, characterized in that the fuel supply is tangential. 7.) Reactor according to at least one of claims 1 to 6, characterized in that the fuel supply takes place in several stages in the axial and/or circumferential direction. 8.) Reactor according to at least one of claims 1 to 7, characterized in that the conical lower part (15; 28) is surrounded by an air box (16; 29) from which air enters the conical lower part. 9.) Reactor according to at least one of claims 1 to 8, characterized in that a double jacket (28b') arranged at a distance from the outer surface of the conical lower part (28) is provided in the air box (29). 10.) Reactor according to at least one of claims 1 to 9, characterized in that at least the cylindrical upper part (3; 13; 26) is lined with brick. 11.) Reactor according to at least one of claims 1 to 10, characterized in that in addition to the brick lining, an external single- or multi-layer insulation is provided. 12.) Reactor according to at least one of claims 1 to 11, characterized in that the Reactor has a forced-flow cooling jacket (22). 13.) Reactor according to at least one of claims 1 to 12, characterized in that the outlet opening (39) is followed by an afterburning chamber (40) with a larger diameter than the outlet opening and with a lateral exhaust gas outlet (41).