SE515645C2 - Camera-supplied supply fluid for a combustion chamber - Google Patents

Abstract

A device for supplying fluid to a combustion chamber (3) of a furnace (2) or technically equivalent plant includes a pipe which has peripheral openings (5e) and which is supported externally of the furnace combustion chamber (3), and means for moving the pipe axially into and out of an opening in the chamber wall. The fluid is supplied through a flexible hose (7). A cleaning device is arranged in a supply device housing (11) and functions to clean the pipe as the pipe moves inwardly and/or outwardly. Threaded plugs that function as nozzles through which fluid is delivered to the chamber are screwed into one or more of the openings (5e). One (9) of the plugs is provided with a camera lens (60) that enables an on-line-study and/or photoelectric recording of the combustion process in the chamber (3) to be made.

Description

515 645 2 A supply device of the type in question must be able to work reliably for a long time in a demanding environment, where not least the pipe inserted in the combustion chamber is exposed to great stresses due to the high temperature and the corrosive environment. The temperature changes that occur when the pipe is pulled out for cleaning, which normally takes place 3-6 times a day, must also be taken into account.

When using incineration plants equipped with supply devices of the specified type, there is a desire to streamline the incineration process and reduce environmentally harmful emissions.

To achieve this, it is important to have as detailed knowledge as possible about the combustion process. The proposals made so far in this respect have not been entirely satisfactory, e.g. since it has not been possible to carefully study several of the parameters, for example the color and intensity of the combustion gases and particles in different parts of the combustion chamber, which is important for an efficient combustion process. An object of the present invention is to eliminate this fact.

Brief description of the invention A supply device according to the invention which fulfills this object is of the type specified above and has the features stated in the characterizing part of claim 1.

The invention has the advantage that - especially when at least one of the camera lenses consists of a wide-angle lens - in principle the entire fireplace, both upstream and downstream of the pipe in question, can be continuously filmed and visualized, e.g. on display in a control room. Automatic control of the combustion process via computer-aided image analysis for the greatest possible efficiency with careful consideration of environmental aspects is thereby possible.

The plug in which the lens is accommodated is suitably provided with the lens surrounding outflow holes for a purge and cooling fluid. This is preferably the same as that supplied to the combustion chamber. 515 645 3 This purge action amplifies the action produced by the rotatable means, e.g. steel pins or brushes, which are used to clean the pipe during its inward and / or outward movement.

The possibility of utilizing the other air nozzles in that pipe - the number of which can vary between, for example, 10 and 50 - supplied process air for blowing the camera lens clean and also for cooling entails a special advantage.

The lens together with the associated part accommodated in the plug is suitably located at such a radial distance from the peripheral surface of the plug that convective and radiant energy can be transferred from the cold tube wall to the lens.

For efficient cooling of both the nozzle-supplied supply tube and the camera lens, this is suitably provided in claim 6 resp. 7 indicated strokes.

The invention also offers the possibility of using computer-assisted image analysis to continuously - by turning the tube - adjust angles, flow and pressure of the outflowing air as the image analysis gives a signal or information that the surrounding conditions change.

In practice, it is preferred that the supply device be provided with a motor, e.g. an electric motor with chain drive, which automatically rotates the tube to the appropriate setting positions depending on the result of the image analysis.

The above-mentioned helical path of the coolant both on its passage to the inner end and on its return towards the outer end makes the cooling extremely efficient, which increases the service life of the supply device.

The coolant tube or tubes and the return passage suitably have connections located at the outside of the outer jacket, preferably in the form of quick couplings to flexible hoses such as u. U; -. .. U m. ,. . u. n. .. - «v. u m .n. . .. 9- ou n. -. . . . . . n. u. | »U -v v .. -. . , n.,; 1 e. «Q ... a. . . . . u n 1 v »n» n .u .n 4 may accompany the tube at its axial displacement out of resp. into the combustion chamber.

Additional features and advantages of the invention will become apparent from the following description of an embodiment thereof. The description is made in connection with the attached drawings.

Brief description of the drawing figures Fig. 1 is a perspective view showing in section the combustion chamber of a heat-generating plant such as a waste incinerator provided with a supply device according to the invention for supplying air, which device is in the active position.

Fig. 2 is a perspective view of some essential components of the supply device according to Fig. 1.

Fig. 3 is a perspective view provided with cut-away parts of the fluid pipe provided with an outer jacket and cooling pipe to the supply device according to Figs. 1 and 2.

Fig. 4 is a side view showing the outer end of the fluid tube along with suspension arrangements and connections for the fluid and a coolant.

Fig. 5 is a detail view in the form of a section through a part of the wall of the incinerator and the housing located at the end of the supply device which receives the cleaning devices for the pipe.

Fig. 6 is a vertical section through the tube showing three threaded holes with different angular distances therein.

Fig. 7 is a cross-section through a part of a supply device with a screwed-in plug which accommodates a camera lens and holes for purge air.

Figs. 8A-8C, finally, show three different types of plugs which can be screwed into the threaded holes in Fig. 6. 515 645 - m. Description of preferred embodiments In Fig. 1, the number 2 denotes an incineration plant in the form of a furnace for combustion of solid fuels with a lower grate (not shown) and an upper combustion chamber 3.

The fuel can be supplied intermittently or continuously and combustion air is blown in the form of primary air from below and up through the grate, which generates combustion gases to the combustion chamber 3.

Secondary air is supplied via a number of supply devices, one of which, denoted by the number 1, is shown in Fig. 1. The supply device has an axially displaceable tube 5 which is included in the combustion chamber 3 through an opening in the wall of the furnace 2. The supply means 1 supply secondary air for the purpose of final combustion of formed reaction products in the form of gas and solid particles in the combustion chamber 3.

Some of the particles deposit on the inside of the combustion chamber 3, which is lined with water or steam tubes 4 with an external insulation. Dust particles are also deposited on the supply pipes 5, whereby the holes 5e for the supply of the secondary air can be completely or partially clogged, which thereby has a negative effect on the secondary air supply. This makes the combustion incomplete with additional problems of the specified type as a result.

In a plant of the type in question here, the supply pipes 5 for fluid, e.g. secondary air, arranged to form a curtain system comprising a number of such parallel pipes 5 at one or more levels in the combustion chamber 3. The pipes 5 are provided with nozzle-shaped openings 5e along the entire circumferential surface of the pipes. The openings 5e can have equal division and several rows of openings with different angular distances, which openings can be provided with plugs which possibly serve as nozzles, can be arranged along the pipes in the manner described below in more detail in connection with Figs. 6 and 8. 515 645 : _ï: =; :: ¿: _. A fluid, e.g. secondary air with mixture of concentrated ammonia, recycled flue gas and / or oxygen of high pressure, is supplied via a fan (not shown) connected to a collection box 6 from which flexible hoses 7 emanate which are connected by quick couplings to the end flanges 5b of the pipes 5 .

Depending on the current combustion process, the pipes 5 are inserted in and pulled out in axial direction from the chamber 3 with longer or shorter time intervals, for example 3-6 times per day. In this way, the emission level of the combustion process can be kept optimal.

The supply device 1 shown in Fig. 1 consists of an elongate modular unit which is interchangeably applicable to the wall 2a of the combustion plant 2 in the area of a hole in the tube 5 accommodated therein. The module unit is built around a frame part 10 with in the nearest square section which at one end has a cleaning device in the form of brushed serving steel pins 8 and their drive device which will be described below in connection with Fig. 5 surrounding housing 11 which housing is provided with a connecting flange 11a surrounding the hole in the wall 2a.

The frame part 10 further has an upper guide 12 extending along this for a carriage 13 which, via links 14, 15 and a stirrup 16 surrounding the tube 5, carries the tube 5 in the area of its outer end.

The pipe is then, as stated above, rotatably supported, so that the direction of outgoing fluid flows can be adjusted optimally.

The drive device for the tube consists of an electric motor 20 arranged at the inner end of the frame part 10 which rotates via a chain 21 a shaft 22 which carries a sprocket 23. A further sprocket 25 is mounted on a shaft 26 at the other end of the frame part 10. A chain 24 runs over the sprockets 23, 25 which is connected via a connecting element 27 to the link arm 15, ie so that the tube 5 is displaced in either direction depending on the direction of rotation of the electric motor 20.

The guide 12 arranged in the area of the roof of the frame part 10 has lower angled legs which form a downwardly directed opening in which the downwardly directed central part 5a of the T-shaped carriage 13 projects. The carriage 13 can slide on the beam serving as a guide or have wheels or rollers to facilitate the movement.

As can be seen from Fig. 3, the tube 5 consists of an outer jacket 5a provided with nozzles 9 or nozzle openings 5e and an inner tube 5b which at its outer end has a connecting flange 5k for a coupling 7a on the flexible hose 7. Each tube 5 may have t .ex. three rows of nozzles or nozzle openings 5e which rows are arranged at different angular distances from each other. This offers the possibility to either set the most optimal position for the pipe by turning and / or to plug one or more nozzle openings or all nozzle openings in one or more rows with plugs that do not have holes or with nozzles with holes in connection with the installation of the device. with the same or different diameter, so that the fluid flow from the pipe has the direction and size most appropriate for the combustion process.

Both the outer jacket 5a and the inner tube 5b have a closed inner end and are accommodated to some extent by three coolant tubes 5e which run helically around the inner tube 5b. At the outer end, the coolant pipes 5c are provided with a connection covered by a cover 51, e.g. a quick coupling, to a flexible hose 30 for supplying coolant. A similar cover 5f covers a connection, e.g. a quick coupling, for a further flexible hose 31 via which the coolant is discharged.

The coolant pipes 5c are open at their inner end, so that the coolant leaving the pipes receives a helical return passage 5i in the spaces between the outer jacket 5a, the inner pipe 5b and the coolant pipes 5c. The arrangement shown in Fig. 3 allows a very efficient cooling of the tube 5.

The cross-section according to Fig. 5 is intended to illustrate that the housing 11 for the cleaning devices has two or more opposite sets of steel pins supported by holding means, such as brushes serving steel pins 8, the holding means during the displacement movement of the pipe into resp. out of the combustion chamber 3 itself performs a controlled rotating movement around the tube 5. Thereby the centrifugal force is used for efficient cleaning of the tube.

In more detail, the brushes 8 are arranged on a holder 40 which is supported by a rotatable shaft 41 at one end of which there is a gear 42 which rolls against a ring ring 43 fixedly mounted with inner teeth. The shaft 41 is via a ball bearing 50, bushing 51 and the holder 49 attached to a sprocket 48. Rotational force for rotation is transmitted via a chain 47 driven by a motor (not shown) which engages against the sprocket 48. The sprocket 48 is in turn mounted to the ring ring 43 via V-shaped wheels 44 which engage in a similarly V-shaped groove in the periphery of the ring ring 43.

The described construction means that the brushes 8 rotate at high speed and strongly - but also gently - strike the tube 5 so that soot and other particle coating are effectively removed. At the same time, the axial displacement of the pipe means that its entire jacket surface is machined with the nozzle openings. The entire unit 39 with the steel pins 8 is easily replaceable after loosening the shaft 41 provided with nut and bolt head.

Fig. 7 shows a plug 9 screwed into the hole 5c in the tube 5 which is provided with a camera lens 60 which via a connection line 61 enables on-line study and / or photoelectric registration and via signal to for example a pressure and flow regulating fan gives the possibility to influence the combustion process in the chamber 3. The lens 60 is a wide-angle lens that enables, in principle, the entire fireplace to be continuously filmed and visualized directly on a monitor or via video in a control room.

The plug 9 accommodates a large number of outflow holes 63 with a small diameter for purge and cooling of the lens 60 with purge air which consists of the process air supplied to the combustion chamber 3.

The lens 60 and its connecting line 66 are further cooled with ambient cooling fluid, i.e. water in the spiral flow described above and can thereby be kept clean from coatings. To nnn .nn nn .n nn nn nnnn nn nn nn nn -nnn n. the cleaning via the brush system described in connection with Fig. 5.

The part 60a of the camera lens 60 in the plug 9 is located at such a distance from the periphery of the plug that convective and radiant energy can be transferred from the cold tube wall to the lens.

The pipe 5 is further provided with an electric motor (not shown) which via chain drive (not shown) enables rotation of the pipe 180 ° in each direction.

This makes it possible to continuously adjust the direction, flow and pressure of the air flowing out of the plugs 9 ", 9" 'by means of computer-assisted image analysis via the camera lens 60 so that an efficient combustion process can be achieved as the image analysis gives signal resp. information on changes in the underlying conditions.

When applying and trimming the supply device, a precise determination must be made as to which nozzle openings 5e are to be open, which thus also means that the others must be plugged. The camera can also be used for this. In connection with this analysis, it is also important to know the temperature in the combustion zone where the pipe 5 is located.

For this important determination, the tube itself can be used, namely if a temperature sensor 60 is fitted in the area of the inner end of the tube, e.g. as shown in Fig. 3 in the closed inner end wall of the tube.

Accurate mapping of current temperature zones can be undertaken by gradually inserting the pipe, e.g. half a meter at a time, and that a reading of the temperature is made at each stop. In this process, the camera can also be used.

After the distribution of the temperature zones has been mapped, it is determined which nozzles 9 are to be open and which are to be plugged for best function. During the test process, a rotation of the pipe can also take place when, as stated above, the pipe is arranged so that such rotation is allowed. In the embodiment shown in Figs. 6 and 8A-8C, the tube has three rows of nozzle openings 5e which have mutually different angular distances, e.g. 90 °, 120 ° resp. 150 °. If all the nozzle openings 5e in a row are provided with plugs 9 'of the type indicated in Fig. 8A, i.e. missing holes, depending on the rotational position of the pipe 5, the two outgoing fluid jets can form corresponding angles with each other. Other nozzle openings 5e can be provided with nozzles 9 "or 9" ', respectively, of Figs. Fig. 8C shows the type whereby also the size of flows flowing from the pipe can be regulated. For example, nozzles 9 'with small holes can be arranged near the outer end of the pipe while nozzles 9 "with large holes are screwed into the inner end of the pipe. In this way different flows in the longitudinal direction of the pipe can thus be achieved.

Several different types of threaded nozzles 9 ", 9" ', e.g. with hole diameters 5, 10, 12, 15 and 20 mm, can be used.

Service on the oven system is normally available so that the previously used module unit is removed and a new one is applied by connecting in the same place as the removed one. For best function, a test of the specified type is performed before normal use of the new module unit begins. Maintenance and service of the removed module unit can therefore be carried out, e.g. at the factory.

In normal combustion plants to which supply devices according to the invention can be used, the pipes usually have a length of 3-6 meters. However, both larger and smaller pipe lengths can be considered. The modular construction of the supply means that it is a comparatively simple operation to adapt it to the desired pipe lengths in different individual cases.

Claims (8)

uuu .uu uu .u .u u. uuuu uu uu uu uu uuu uu uu uu uu uu uu uu uu uuuu uu u .. u. m- c ll Claims A supply device for a fluid to a combustion chamber (3) in a heat generating plant, e.g. a boiler or oven (2), which supply means (1) comprises a) a pipe (5) supported outside the plant, provided with peripheral holes (5e), b) drive means (20-27) for axial displacement of the pipe (5) into in and out of the plant through a hole in its wall, c) means (13-16) for displaceable support of the pipe at its outer end, which means are designed so that rotation of the pipe is allowed, d) at the outer end of the pipe (5) located connecting means (5g) for a flexible hose (7) for supplying the fluid from a supply source, e) rotatable means, e.g. steel pins (8) or brushes for cleaning the pipe during its inward and / or outward movement, f) supply means (30) for coolant to the pipe (5), g) one or more preferably threaded holes or openings (Se) in the pipe (5) ), in which holes plugs (9, 9 ', 9 ", 9"') are applicable, preferably screw-in, characterized in that one or more of the plugs (9) have a camera lens (60) which via an associated connecting line (61) enables on-line study and / or photoelectric recording to influence the combustion process in the chamber (3). A supply device according to claim 1, characterized in that at least one lens (60) is a wide angle lens. A supply device according to claim 1 or 2, characterized in that the plug has the lens surrounding outflow holes (63) for a purge and cooling fluid. A supply device according to claim 3, characterized in that the purge and cooling fluid is the same as that supplied to the combustion chamber (3). 515 64 5jïI =. I * 12 Supply device according to Claim 3 or 4, characterized in that the lens (60) and the associated part accommodated in the plug (9) are at such a radial distance from the peripheral surface of the plug that convective and radiant energy can be transferred from the cold tube wall to the lens. . Supply device according to one of Claims 1 to 5, in which the pipe has an outer jacket (5a) provided with the peripheral plug holes, characterized in that one or more coolant pipes (5c) extend helically between the inner pipe (5b) and its outer jacket (5a). ), the coolant tube or tubes (5c) being open at their inner end and the inner tube (5b) and the outer jacket (5a) closed at the inner end, so that the coolant obtains a helical return passage (5i) in the spaces between the outer jacket (Sa), the inner tube (Sb) and the coolant tube or tubes (5c). Supply device according to claim 6, characterized in that the helical coolant pipes are replaced by walls between the pipe and the surrounding jacket. Supply device according to one of Claims 1 to 7, comprising a drive device for rotation of the pipe, characterized by means for continuously and automatically adjusting the flow direction, flow and pressure for fluid supplied via the pipe nozzles in accordance with computer-assisted image analysis in accordance with signal obtained by means of the image analysis resp. information on the combustion state of the chamber.