Device for burning waste and similar solids

Abstract

975,545. Refuse-consuming furnaces. METALLBAU SEMLER G.m.b.H. Oct. 26,1962 [June 8, 1962], No. 40570 / 62. Heading F4B. Apparatus for burning solids, e.g. garbage, comprises a rotary frusto-conical drum 16, Fig. 2, formed with perforated walls and disposed in a furnace 6 with the axis of rotation 17 inclined upwardly towards the open bore of the drum so that the lowermost surface line 16<SP>1< / SP> is either horizontal or downwardly inclined away from the axis, a charge shoot 37 feeding the drum through said open base, and an air supply pipe 19 feeding a tuyere 19<SP>1< / SP> shaped to the contour of the drum and encouraging the establishment of a combustion zone slightly offset from line 16<SP>1< / SP> and into which rotation of the drum continuously tumbles the burning solids. Combustion gases leave the furnace by a flue 12 formed with a constriction 12<SP>1< / SP> and a tangential air inlet 40 to encourage deposition of solid particles &c. are then divided into two streams. One stream is diverted by a fan 14 and pipe 13 to a feed hopper 4, where it mixes with air entering at 5 to preheat incoming material, a fan 9 then drawing off the mixed gases, diluting them with further air supplied through pipe 10 and supplying the resultant mixed gases to the pipe 19. The other stream is drawn by fan 46 through washing towers 41 and 44 and fed to chimney 47, drawing in air and discharging the mixture through a restricted outlet 50. Ignition is by a burner disposed near the tuyere 19<SP>1< / SP> and small ash falls through the perforations 18 in the drum into ash-pan 25 which may be withdrawn through closable opening 38. Large particles are periodically discharged into said ash-pan by tilting the drum about axis 21 and opening hinged flap 24. The drum is rotated at 20-40 r.p.m. by a motor-driven gear having pins engaging a pin ring 26 held by rollers 32, 34 mounted on a frame 30. The perforations 18 have a diameter of 10-20 mm., being arranged at a spacing of 5-10 mm., and the cone angle for the drum is 90-120 degrees.

Description

[0001] Device for burning waste and similar solids The invention relates to a device for burning waste and similar solids, with a rotatably mounted drum equipped with a rotary drive, which moves the material being burned from a can be fed in from the front and from which the combustion residues can be at least partially removed through a multitude of openings in the drum shell. are removable, and have a supply line for combustion air and a drain for the exhaust gases.

[0002] In a known device of this type, the drum is designed as a cylindrical rotary tube, the shell of which consists of a bar grid. The rotary tube is mounted horizontally with its cylinder axis. A nozzle tube inserted axially into the rotary tube forms a burner and simultaneously the air supply line. The material to be burned is introduced into the rotary tube at one end and moves as a result of the formation of air. The angle of repose and the rotation of the pipe towards the other end continuously expel the small, burned particles. the grate wall separated out, so that at the end of the rotary tube furthest from the point of application a mixture of non-combustible and large, flammable, but not yet completely burned-out particles are formed. This mixture does not burn completely even if the rotary tube The process is made exceptionally long. This is because the temperature in the burnout zone cannot be kept high enough to burn off the large, combustible particles. The parts are not completely burned out. Rather, the forced combustion air cools the non-combustible parts significantly, so that they become susceptible to combustion. Parts of the material absorb heat and the combustion process stops. Therefore, if solids of uneven quality are burned in rotary kilns and If the material is granular, such as waste, then at the end of the rotary tube you get a mixture that still contains a significant proportion of combustible materials. contains. Even in the main combustion zone of the rotary tube, combustion proceeds relatively slowly, due to the rotation of the Ash particles dragged up the sides of the pipe repeatedly fall back into the combustion zone until they escape through the grate wall.

[0003] A device is also known which serves to feed the combustible components of waste in shredded form to a generator. For this purpose, the waste is fed through an inclined rotating pipe into a sieve cage consisting of two counter-rotating truncated cones. In the In the first cage section, which widens in the direction of the waste flow, the fine particles of the waste are sifted out from the beginning and fall into a Shaft, from which they can enter the generator. The larger pieces migrate into the tapered section of the sieve cage and They are exposed there to the flue gases from a combustion chamber. However, these flue gases are not intended to burn the waste. Rather, they are only meant to... They coke up and break down into smaller, even more combustible particles. These smaller particles migrate back into the area above the shaft. The lying section and then fall into the shaft. The large, non-combustible pieces are then periodically removed through an opening in the tapered section. The end of the sieve cage is removed. The known device is therefore used for sifting and shredding waste in order to prepare it for recycling in a To prepare the generator. A true and complete combustion does not take place in the sieve cage.

[0004] Finally, a device for separating granular material is known. This consists of a conical drum with a conical opening angle. over 90°, which is mounted such that the lowest conical generatrix runs essentially horizontally. The drum shell is closed. Brings When the granular material is placed into the drum, the parts that slide or roll smoothly on the drum surface are directed towards the base of the cone. the particles move towards the drum shell, while the parts adhering more strongly to the cone tip migrate towards the apex. The separated particles can therefore They are pulled off on the one hand at the open base of the cone, and on the other hand at the tip of the cone, and are therefore dependent on their sliding or rolling properties. Separated. This well-known device is used only for separating granular materials. No combustion takes place.

[0005] The invention is based on the objective of designing a device of the type described above in such a way that, in small Device dimensions enable complete, rapid and economical combustion of combustion materials of inconsistent quality, especially of waste, this can be achieved according to the invention by making the drum obtusely conical in a manner known per se. The shape has an open base for introducing the material to be burned and a cone opening angle of approximately 90 to 120°, and is angled towards the base of the cone. is mounted under such an angle of rising axis of rotation that the lowest generatrix of the cone is horizontal or slopes slightly downwards towards the base runs and that the supply line for the combustion air ends in a nozzle that is directed towards an area of ​​the drum shell in which As the drum rotates, the conical shape of the drum results in a rotating flow of the material being burned.

[0006] The invention makes use of the phenomenon known from the known device for separating granular material, namely that at Particles adhering to the drum shell are dragged towards the cone tip, while well-rolling particles repeatedly move towards the open end. move back towards the base of the cone. The large portions of the combustion material therefore always return to a specific zone and lead to... This results in a kind of rotational movement. When combustion air is supplied to this zone, a combustion process occurs there after the combustion material is ignited. a combustion zone from which the fine ash particles are dragged out towards the cone tip and through the openings in the drum are separated out. In contrast, the larger, less combustible and non-combustible parts repeatedly enter the combustion zone. They return and burn completely there. It is essential that the coarse materials move back along the rotational flow. Mix these with the newly added substances, so that the large, difficult-to-burn parts are constantly separated from fine, rapidly combustible parts. are surrounded. Therefore, no mixture of non-combustible parts with large, still combustible parts forms, the combustion of which, however, is caused by The heat extraction is hindered. Rather, the combustion of the highly flammable parts that enter the combustion zone contributes to this. The resulting heat of combustion contributes to the combustion of the large, difficult-to-combust parts. It is then only necessary to completely to remove non-combustible residues from the drum from time to time. In this way, a small device is used in a very confined space. Complete and rapid combustion is achieved even with very unevenly textured materials.

[0007] In the preferred embodiment of the invention, a [missing element] is located at the outlet of the exhaust pipe in the area above the drum. A constriction is provided to accelerate the exhaust gas, and a nozzle for supplying air is provided tangentially in the direction of flow upstream of the constriction. The exhaust gas is connected in such a way that a rotational flow forms in the area of ​​the outlet. This flow is drawn from below through the combustion material. The combustion air flowing through carries ash particles and individual unburned particles into the exhaust pipe. These are partially in ejected by the rotating flow forming in the area of ​​the constriction and - insofar as they are still flammable - in the rotating flow The hot exhaust gases completely burn off the contents. This prevents any unburned particles from leaving the device.

[0008] The invention is described below with reference to an exemplary embodiment, with further advantageous embodiments of the invention. will be explained.

[0009] Figure 1 of the drawing shows a side view of a device according to the invention with a cutaway housing in simplified form. Illustration and in Fig. 2 a front view of the drum of the device according to Fig. 1 in the direction of arrow III in Fig. 1.

[0010] The combustion device 6 consists of a core component: a drum 16, which is rotatably mounted about an axis 17. The casing of the Drum 16 has a multitude of small perforations 18, which are formed as small holes with a diameter of about 10 to 20 mm and with gaps of approximately 5 to 10 mm web width. The drum 16 is mounted such that its lowest lateral line 16' in essentially horizontal or inclined at a small acute angle to the horizontal, as shown in Fig. 1. Below drum 116 is An air supply line 19 is provided, which opens into a nozzle 19'. In the illustrated embodiment, the walls of the nozzle are 19' is brought close to the drum shell and adapted to its outer shape. As Fig. 2 shows, the 19' fitting is located on a Position which is offset at an angle from the lowest generatrix 16' in the direction of rotation of the drum 16 indicated by arrow B in Fig. 1. This creates a limited air supply zone 20, which is shown as a dashed line in Fig. 2. This zone 20 extends over a large part of the axial length of the drum 16. In width, it extends over approximately 15 to 30 degrees of arc. In the area of ​​zone 20, a [missing word] forms in the Drum 16 has a combustion zone for reasons that will be described below. Furthermore, a [missing element] protrudes into the drum in the area of ​​zone 20. an unillustrated pilot burner, which may be of conventional design, is inserted. The limited air supply zone 20 can also be formed by, that the nozzle of the air supply line is designed as a nozzle that directs the air through the drum shell in a limited area blows through it.

[0011] As can be seen in particular from Fig. 1, the drum 16 has a frustoconical shell, the base of which is open and It is used for introducing solids to be burned. The cone opening angle is suitably about 90 to 120°. The rotational speed at The circumference of the drum is preferably dimensioned to approximately 20 to 40 m / h.

[0012] A counter cone 22 or a cylinder can be attached to the side of the largest diameter of the drum, thereby allowing a larger quantity material to be incinerated can be introduced into the drum. In the area of ​​the smallest diameter, the The drum is provided with an opening 23, which is closed by a pivoting flap 24. Through this opening, by pivoting the The drum is emptied around an axis 21 perpendicular to the axis of rotation 17, after opening the flap 24, so that the larger non-combustible residues are emptied.

[0013] The solids to be burned are introduced into the drum 16 on the side with the largest diameter, specifically on the side of the The outlet 19' of the air supply line 19 is on the side opposite the vertical center plane. The supply direction is shown in Fig. 2 by An arrow C is indicated. The rotation of drum 16 in the direction of arrow B carries the filled solids along and through the The particles are passed through combustion zone 20. The smaller particles are burned in a single pass through the combustion zone. and fall as ash through the openings 18 into an ash collection container 25. The larger pieces roll through the openings after passing through the openings 18. return to the combustion zone and execute a circular motion indicated by arrow D in Fig. 2. This circular motion leads to the burning larger parts are passed through the combustion zone several times until their combustible portion is completely burned and as ash from the drum. The large, non-combustible residues are removed from time to time by tilting the drum. Axle 21 emptied.

[0014] The conical shape of the drum 16 has two particular advantages: Firstly, when the conical drum rotates around the easily accessible Horizontal inclined axis 17 in the drum, the circular to kidney-shaped movement of the combustion material indicated by part D, by the constantly changing surfaces are exposed to the supplied combustion air, resulting in complete combustion. Secondly, In the drum, the finer particles separate from the larger ones; the finer particles adhere more strongly to the drum wall and are thus separated. This causes them to be dragged further out of the combustion zone and, as they roll back, they gradually migrate towards the tapered end of the drum. This separates the small, burned ash particles from the larger solid particles that still need to be burned. This facilitates, among other things, the The ash falls out through the openings 18 and, on the other hand, keeps the combustion zone 20 free of already burned parts.

[0015] In order to be able to set the drum 16 in rotation, it is surrounded in the area of ​​its largest diameter by a ring of pins 26, which consisting of a closed ring 26' arranged at a distance from the drum circumference and a plurality of pins 26" arranged in regular intervals are arranged at angular intervals and connect the ring 26' to the drum circumference. A gear 27 engages in the pin ring 26, which is connected to a The gear is provided with stock teeth. The stock teeth are formed by pins 28 projecting radially from the wheel hub. The gear 27 sits on a Drive shaft 29, which is connected to a drive motor, for example via a chain drive (not shown). The pin ring 26 is rotatable. The drum is mounted in a frame 30 surrounding it, which is pivotable about diametrically opposed pins 31. The pins 31 form the horizontal pivot axis 21. The drive shaft 29 passes through one of the pins 31, which is hollow for this purpose. Crossed guide rollers 32, 34 are provided for the rotatable bearing of the pin ring 26 on the frame 30, which are loosely rotatable with pivot pins 33. The rollers 32 are mounted, for example, in the polygonal frame 30. The rollers 32 rest against the outer circumference of the ring 26', while the rollers 34 Support the ring 26' from below. The drum is held in the desired inclined position by a rope 35 attached to the frame 30. To When the drum is swung into the unloading position, the rope 35 is unwound from a winch drum (not shown).

[0016] The drum 16 is arranged in a closed housing 36, which has an insertion opening 37 for the solids to be burned. The housing 36 also has a closable removal opening 38 through which the ash and residues can be removed from the housing. can be. Finally, an exhaust opening 39 for the combustion gases is provided at the top of the housing 36.

[0017] Above the drum, in the area of ​​the extraction opening 39, a constriction 12 is provided, to which the opposite constriction is attached. A further exhaust pipe 13 connects. A nozzle 40 opens tangentially into the chamber formed by the exhaust opening 39 before the constriction 12. Direction. Cold air or exhaust gases can be introduced through this, so that a chamber formed by the exhaust opening 39 A rotational flow is created. As symbolized by arrows in Fig. 1, this rotational flow has a larger shape at the pipe wall. The density of the drawn-in cold gases determines the flow component that is directed towards the interior of the furnace, while in the core of the rotational flow A flow component directed into exhaust pipe 13 is present. The rotational flow causes particles contained in the exhaust gas to be disturbed. ejected and returned to the furnace along the walls by the flow component directed towards the furnace interior. If by When air is drawn in through the nozzle 40, it mixes with the flame, creating a chamber in the area formed by the exhaust opening 39. an afterburn takes place.

[0018] The hot exhaust gas escaping through line 13 can be used to preheat the material being combusted. In this case, From the exhaust pipe, an undrawn branch pipe leads to the open end of a collection container for the solid material to be burned. Furthermore, From the outlet end of the container, another line is led to the air supply line 19, so that diverted exhaust gases are supplied together with combustion air. The material being combusted flows through the container in direct current, thus heating the material. A [missing information] leads into the branch line. Air intake line that is adjustable in such a way that a mixing temperature of approximately 550 to 600°C is achieved in the branch line before entering the container. The delivery rate in the branch line can also be adjusted so that the gas mixture temperature in the container is less than 350°C. This achieves good preheating without the risk of burning the solid material in the container before it enters the the drum would consist of 16.

Claims

[0019] Claims:

1. Device for burning waste and similar solids, with a rotatably mounted and with a A rotary drive equipped drum into which the material to be burned can be fed from one end and from which the combustion residues are extracted. are at least partially separable through a multitude of perforations in the drum shell, and are equipped with a supply line for combustion air. and a drainage system for the exhaust gases, characterized in that the drum (16) has a blunt conical shape in a manner known per se for insertion of the combustion material has an open base and a cone opening angle of approximately 90 to 120° and extends towards the cone base at such an angle is mounted on an ascending axis of rotation (17), such that the lowest generatrix (16') of the cone runs horizontally or slightly downwards towards the base, and that the supply line (19) for the combustion air opens into a nozzle (19') which is directed towards an area (20) of the drum shell in which 2. Device according to claim 1 1, characterized in that the feed line (19) with the nozzle (19') in the outlet area has a nozzle arrangement for accelerating the combustion air is formed.

3. Device according to claim 1, characterized in that the openings are holes (18) with a diameter are formed from approximately 10 to 20 mm.

4. Device according to claim 1, characterized in that the rotational speed is greatest The circumference of the drum (16) is approximately 20 to 40 m / h.

5. Device according to one of claims 1 to 4, characterized in that the The conical base of the drum (16) is a cylindrical or frustoconical projection (22) converging in the opposite direction to the drum cone with is attached to a closed casing.

6. Device according to one of claims 1 to 5, characterized in that the drum (16) in the area The smallest diameter has a suitably closable drain opening (23).

7. Device according to one of claims 1 to 6, characterized in that the drum (16) is pivotably mounted about an axis (21) perpendicular to the axis of rotation (17). B. Device according to a of claims 1 to 7, characterized in that the drum (16) is surrounded in the region of its largest diameter by a ring of pins (26), which is rotatably mounted on its outer circumference in a frame (30) such that the frame rotates about two diametrically opposed horizontal pin (31) is pivotable, and a drive shaft (29) is passed through one of the two pins, which is hollow, and which is connected to a a toothed gear (27) provided with a stock toothing (28) engaging in the pin ring.

9. Device according to one of claims 1 to 8, wherein characterized in that guide rollers (32) are loosely rotatably mounted on the frame, which surround an outer ring surrounding the drum (16) at a distance. (26') of the pin ring (26).

10. Device according to one of claims 1 to 9, wherein the material to be incinerated in the drum is drawn from a container is feedable and preheatable by means of the exhaust gases, characterized in that a branch line leads from the exhaust gas line (13) to the atmosphere The air is routed to the open inlet end of the container, and another line is connected to the outlet end of the container, which leads into the air supply line. (19) discharges in such a way that diverted exhaust gases together with combustion air flow through the container in the same direction as the material being combusted.

11. Device according to claim 10, characterized in that an air intake line opens into the branch line, which is controllable in such a way that The branch line, before entering the container, establishes a mixing temperature of approximately 550 to 600°C.

12. Device according to claim 10 and / or 11, characterized in that the delivery rate in the branch line is adjustable in such a way that a mixing temperature is maintained in the container of the gas of less than 350°C.

13. Device according to one of claims 1 to 12, characterized in that at the opening (39) The exhaust gas line (13) in the area above the drum (16) has a notch (12) that accelerates the exhaust gas and is directed in the direction of flow. A nozzle (40) for supplying air or exhaust gas is connected tangentially in front of the constriction in such a way that a forms a rotational flow. Considered documents: German patent specifications no. 498 070, 481089; French patent specification no. 544 993; Swiss patent no. 2 082 870; British patent no. 235 738; US patent no. 105 891.