AN ARRANGEMENT FOR DRYING NATURAL MANURE AND THE LIKE

Abstract: Arrangement for preventing material which is to be dried from burning fast onto a base part (2) in an arrangement which is preferably designed for drying natural manure and the like, and comprising at least one stirring arm (9) connected to a drive axle (8). The arrangement according to the invention makes it possible for the stirring arm (9) to follow the base part (2) effectively and to remove all the material effectively therefrom. The arm (9) is formed of two elements (48, 49) which are movable relative to each other, namely, a preferably tubular holder (48) which support a scraper arm (49), preferably equipped with an adjustable blade (50), with floating suspension, that is to say, the scraper arm (49) can carry out vertical pivoting movements and can also be lifted and lowered in its entirety without pivoting. The scraper arm (49) is mounted in the holder (48) by means of a part (54) at two mounting points (55; 56) located at a distance from each other, mounted in such a way that the scraper arm (49) is acted upon by devices which strive to lift up and swing down the said arm (49) respectively.

Description: An Arrangement for Drying Natural Manure and the like The present invention relates to an arrange ment for preventing material which is to be dried from bur ing fast onto a base part in a drying arrangement which is preferably intended for drying natural manure and similar material. The arrangement according to the invention can be used in drying arrangements of the kind which is described in Swedish patent specification No. 396,994, for example. The drying arrangement shown in this patent speci fication comprises a container in which the manure materia is heated, the said container being constituted by a close vessel equipped with an inlet aperture for introducing moi manure and an outlet for removal of the dried product; thi closed vessel contains an upper and a lower " chamber which are separated by a partition wall made of heat-conducting material. In the known arrangement the upper chamber is designed to receive moist manure, while the lower chamber is in communication with devices for indirectly heating th manure via the said partition wall, which also forms the base of the upper chamber. A stirring device moves over this base with the intention of preventing the material de tined for drying from being burnt fast onto the base. With the previously-known arrangements of this kind which have a stirring device it was found that the stirring devices were not able to follow the base of the upper chamber effectively and thereby remove all the material from it; this was caused by, amongst other things, movement at this base due to uneven heating. Problems have also been found to arise due to uneven heating of the diffe rent parts of the partition wall. The object of the present invention is there fore to provide an arrangement in which the above-mentioned drawbacks are eliminated, so that the optimally effective scraping clear of the base of the upper chamber is achieved without the danger of the stirring devices jamming, for example, due to thermal fluctuations at the bottom of the chamber. The said object should contribute to increas¬ ing the capacity of the arrangement relative to the energy supplied to it, whilst at the same time the danger of ope¬ rational disturbances is considerably reduced, compared with previously known arrangements of this kind. The said object is achieved with an arrange¬ ment constructed according to the invention which is pri- marily characterised in that a stirring arm connected to a drive axle and designed to move over the said base part is formed of two elements which are movable relative to each other, namely, a preferably tubular holder which sup¬ ports a scraper arm, which is preferably equipped with an adjustable blade, with floating suspension, that is to. say, the scraper arm can carry out vertical pivoting movements and can also be lifted and lowered in its entirety without pivoting, due to the fact that the scraper arm is mounted in the holder via a part at two mounting points located at a distance from each other, mounted so that the scraper arm is acted upon by devices which strive to lift up and swing down the said arm, respectively. The invention is described in the following with reference to the accompanying drawings, wherein Fig. 1 is a perspective view looking obli¬ quely from above onto a drying plant in which the stirring device according to the invention is preferably to be used. Fig. 2 is a perspective view from the same direction, "with certain parts of the appliance cut away for the sake of clarity, Fig. 3 is a perspective view of a stirring device arranged inside the appliance, with certain parts cut away for the sake of clarity. Fig. 4 is a corresponding perspective sectio al view of a part of the stirring device shown in Fig. 3, o a larger scale, and OM Fig. 5 is a schematic plan view of the arrangement viewed substantially in a horizontal section through the lower chamber. The arrangement shown on the drawings con- sists of a vessel which is designated 1 as a whole and the inner volume of which is divided into an upper chamber 3 and a lower chamber 4 by means of a horizontal intermediat base 2. The top 5 of the upper chamber has an aperture 6 for introducing moist manure, and also a central aperture through which there passes a drive axle 8 for a stirring device 9 disposed in the upper chamber, which can move ove the upper surface of the intermediate base 2. The feed inl aperture 6 can be closed by means of a pivoting door 10, the movement path of which is indicated with a double arro 11. At the bottom of the upper chamber there is another aperture 12 for extracting the dried material. This aper¬ ture can be closed by means of two flaps 13 which are fixed in the intermediate base by means of hinges and the move¬ ment path of which is indicated by the two arrows 14. The lower chamber is divided into two sections A and B which are separated by means of a first vertical wall 15 which extends from the outer wall 16 of the chamber to a post 17 in its centre, and also by a further vertical wall 18 which extends from the central post 17 radially towards a part of the chamber wall 16 located on the other side of the dis¬ charge aperture 12. Between the vertical wall 18 and the chamber wall there is a through- low opening 19 for air flowing in through a hole 20 in the wall in the vicinity of the dividing wall 15, the flow path of this air will be described later, in more detail. An outflow hole 21 is arranged on the other side of the dividing wall 15. Further more, in the wall of the lower chamber some way from the outflow hole 21 there is a further outflow hole 22, the function of which will be described later. 23 designates a burner for heating up a gaseous medium flowing into the chamber 4. 24 designates an air supply fan which communi- f ~ - A - cates with the burner 23 via a pipeline 25 and a heat- exchanger 26. The space 27 inside the heat-exchanger 26 is in communication with the outlet hole 22 in the chamber 4 via a pipeline 28, and is also in communication with the external air via a pipeline 29. 30 designates a fan which is in communication with the inlet hole 20 via a pipeline 31 and is also in communication with the outlet hole 21 via a pipeline 32, as well as being in communication via a pipeline 33 with an outer pipe 34 through which there passes the section 25a of the pipeline 25 which is disposed after the burner 23. An enclosing space 35 is therefore formed between the pipeline section 25a and the pipe 34. The mouth 25b of the pipeline 25 is located slightly nearer the burner than the mouth 34a of the tube 34. In the embodi ment shown the mouth 34a is located inside the chamber 4. At the end located nearest to the burner the pipe 34 is closed off by means of an annular end-piece 34b. The burner 23 may be oil-operated, for example, but other types of fuel are of course also possible without thereby deviating from the basic concept of the invention. The upper chamber 3 communicates via a pipeline 36 with a condenser 37 in which gases given off during the drying process are condens 38 designates an inlet line and 39 a return line for water which is conducted to and away from the condenser 37, res- pectively. 40 designates an outlet line for condensate and 41 designates a gas outlet line connected to the condenser, which opens " out in the fresh air inlet 42 for the fan 24. 43 designates an electricity supply line " for the fan 24. The upper end of the drive axle 8 is connected to a hydrau- lie motor 44 disposed at the top, which is driven by a hy¬ draulic fluid pump 45 which communicates with the hydraulic motor via line 46. The pipeline 36 terminates at the roof of the upper chamber 3 in an outlet connection 47. Moisture-containing material intended for drying is introduced into the upper chamber 3 via the dLnlet aperture 6, after which the latter is closed. With the aid of the burner 23 the lower chamber 4 is then heated up and heat is transferred to the upper chamber 3 via the intermediate base 2, with simultaneous stirring by means of the stirring device 9 extending radially from the cent- ral axle 8, the construction of this device will be des¬ cribed in more detail below. The stirring device 9 scrapes against the base 2 of the upper chamber 3 and keeps it fre from burnt-on material. Vapour which is given off by the drying material is conducted via the pipe connection 47 an the pipeline 36 to the condenser 37 where the vapour is co densed when it makes contact with parts of the condenser through which there flows the cooling medium flowing throu the pipelines 38 and 39. Condensate, which may be ammonia, amongst other things, is conducted away from the condenser via the pipeline 40. Gases which are not condensed flow ou of the condenser via the pipeline 41 and mix with fresh ai in the inlet nozzle 42. The air/gas mixture obtained is forced via the fan 24 and the pipeline 25 through the heat- exchanger 26 where it is pre-heated, and then past the bur- ner flame 23a where further heating to the desired tempera¬ ture takes place. Combustible gases flowing away from the condenser take part here in the combustion process and contribute to the heating of the plant. After this, the heated gas flows further on through the hole 22, the pipe- line 28, heat-exchanger 26 and out into the open via pipe¬ line 29. A large part of the heat contained in the gases flowing out- is therefore transferred to the incoming gas/ air stream in the heat-exchanger 26. Furthermore, the arran ment has an internal circulation system which is operated by circulation fan 30 which has the pipeline 32 connected to the outlet hole 21 connected to its inlet side. Some of the gas located in the chamber part A is therefore extracted via the hole 21 and the pipeline 32, after which some of this extracted gas is fed via the fan 30 into the chamber part B and circulates back to the chamber A via the opening 19. Another portion of the extracted gas is conduct OMPI via the line 33 to the surrounding space 35 around the central pipeline 25a in the burner system and on into the heating chamber 4 via inlet hole 34a after the gas flowing through the pipeline 33 has been blended with the gas flow- ing through the pipeline 25 in the terminal section of the pipe 34. The gas flowing via the pipeline 33 from the heat¬ ing chamber 4 thereby cools the parts located nearest to the burner and prevents them from being burnt away. Due to the fact that the burner is distanced so that it is located some way from the drying container and since the circulatio air is conducted in on the outside of the burner pipe 25a at the same time as the fan 30 circulates hot air inside the chamber 4, very even heating of the intermediate base is obtained, which means that it stays relatively flat and material intended for drying is moreover prevented from burning onto certain parts of the intermediate base. Due to the new circulation system a very high capacity relative to the volume of the vessel is also obtained, compared with previously-known arrangements of this type. When drying is completed the doors 13 are opened and the dried material is drawn down with the aid of the stirring arm 9, into the shaft 12 from whence it can be removed by means of a screw conveyor, for example. To prevent the stirring arm 9 from binding against the intermediate base 2 when the latter undergoes certain changes in shape due to variations in -temperature, it is necessary for the stirring device to be sprung. As shown on the drawings in Figures 3 and 4, in addition to the drive axle 8 which was mentioned above, the main parts of the stirring device are a holder sleeve 4 connected to the drive axle, an arm 49 which is spring- supported on the holder sleeve 48, and a blade 50 supported by the arm 49. In the embodiment example shown the holder ' sleeve 48 is formed by a four-sided tube 51. The holder sleeve 48 is perpendicular relative to the drive axle 8 and is fixed on the latter via a stub connection 52 which i welded to the side of the tube 51 and the inner diameter of which corresponds to the external diameter of the drive axle 8. Expediently, the drive axle 8 is connected non- rotatably to the stub connection 52 by means of a wedge connection or the like. The arm 49 has a supporting part 53 projecting from the tube 51 and a shaft part 54 project ing into the tube 51. Calculated in the transverse directi of the drive axle 8, the shaft part 54 has a width which corresponds substantially to the width of the hollow space inside the tube 51. Arranged one on either side of the stu connection 52 there are two stub connections 55 and 56 whi are expediently arranged in the vicinity of each end of th tube 51. As is shown most clearly in Fig. 4, the stub conn tion 56, together with an upper end-piece 57 and a lower e piece 58, forms an inner space which contains a compressio spring 59 of the helical type, which rests via its upper end against a pressure plate 60, the outer diameter of which preferably corresponds to the inner diameter of the stub connection 56 and the vertical position of which can be adjusted by means of a bolt 61 extending through the upper end-piece 57. The bolt 61 can be locked to a yoke 62 which extends above the stub connection by means of a lock nut 63. The yoke 62 is supported by two fixing bolts 64 disposed on either side of the bolt 61, which are screwed fast in two projections 65 disposed on either side of the stub connection 56. The lower end of the compression spring 59 rests against a pressure plate 66 which bears a pressure rod 67 which extends downwards through a bore in the lower end-piece 58. The pressure rod 67 rests in turn against the upper face of the shaft part 54. On the other side of the drive axle a horizontal axle 68 passes through the shaft part 54 in its transverse direction. At the top of the axle 68 a bolt 69 is screwed in, with its head resting against a plate 70. The diameter of the plate 70 is slightly less tha the internal diameter of the stub connection 55 and this plate forms the support for one end of a compression spring -W O 71 of the helical type. The other end of the compression spring 71 rests against the lower end-piece 72 of the hollow space inside the stub connection 55. 73 designates a supporting nut firmly screwed on the bolt 69 and rest- ing against the upper surface of the shaft part 54. The compression spring 59 thus strives to press the shaft part 54 downwards, while the compression spring 71 strives to lift up the left-hand section of the shaft part, as viewed in Figure 4. The arm 49 is thereby pressed via its scraper blade 50 against the base 2, both at the end which is located nearest to the drive axle 8 and also at the end which is located nearest to the peri eral wall of the cham¬ ber. Due to the described springing the scraper arm 49 is endowed with floating supension, that is to say, it can carry out vertical pivoting movements and it can also be lifted and lowered in its entirety without pivoting, if this is necessary due to the base changing shape as a resul of thermal fluctuations. The scraper blade 50 is held secur on a projection 74 projecting from the side of the arm 49 b means of adjusting screws 75 and fixing screws 76. To pre¬ vent the arm from moving in the longitudinal direction of the sleeve 48 abutment stops 77 and 78 are screwed to the sections of the shaft part 54 which extend out through the holder sleeve 48. The stop parts 77 and 78 are mounted on the shaft part by means of bolts 79 and 80 respectively disposed adjacent to the end edges of the sleeve 51. The invention is not limited to the stirring device which is described above and shown-on the drawings merely by way of example; the details of this may be modi- fied within the frame of the following patent claims withou thereby deviating from the basic concept of the invention. '^U_.i O

Claims: P a t e n t C l a i m s 1. An arrangement for preventing material which is to be dried from burning fast onto a base part in a drying arrangement which is preferably intended for drying natur manure and similar material, characterised in that a stir ring arm (9) connected to a drive axle (8) and designed t be moved over the said base part is formed of two element (48, 9) which are movable relative to each other, namely a preferably tubular holder (48) which supports a scraper arm (49), which is preferably equipped with an adjustable blade (50), with floating suspension, that is to say, the scraper arm (49) can carry out vertical pivoting movement and can also be lifted and lowered in its entirety withou pivoting, due to the fact that the scraper arm (49) is mounted in the holder (48) by means of a part (54) at two mounting points (55; 55) located at a distance from each other, mounted so that the scraper arm (49) is acted " upon by devices (69, 7^ and 67, 59 respectively) which strive to lift up and swing down thesaid arm (49), respectively. 2. An arrangement according to Patent Claim 1, characterised in that the holder (48) has two hollow space preferably formed ' by stub connections (55, 56) which each accommodate a spring device (71; 59), preferably a com¬ pression spring, which is connected to its lifting or pres ing device (69 and 67 respectively) which is designed to co-act with the said arm part (5^). 3. An arrangement according to Patent Claim 2, characterised in that. the arm-lifting device (69) is forme of a bolt arrangement (69) which has a spring support (70) and which projects in through an end-piece (72) to the arm part (54) to which it is connected, the lifting spring de¬ vice (71) acting between the said spring support (70) and the end-piece (72) in order to lift up the scraper arm (49 4. • An arrangement according to Patent Claim 3, characterised in that the connection between the said part (54) and the bolt arrangement (69) comprises a horizontal axle (68) which is accommodated in a cavity in the said part (54) and is connected to one end of the bolt arrange¬ ment (69) which can be screwed transverse to the said axle (68) and has a supporting nut (73), etc. which can be dis¬ placed along the axle (68) and is designed to rest against the upper face of the arm part. 5. An arrangement according to any of patent Claims 2 - 4, characterised in that the arm-pressing device (67) is formed by a movable pressure rod (67) together with an adjustment arrangement (61) which is connected to the holde (48) and the respective opposite ends of which bear a stop (66 or 60 respectively), against which the said compression spring device (59) acts so that the lower end of the press¬ ing device (67) comes to rest on the arm part (54) and presses the scraper arm (54, 49) in a downwards direction, the said adjustment arrangement (61) preferably comprising a threaded bolt (61) which extends through a yoke (62) which is fixed to the holder (48), and also a lock nut (63) which co-acts with the yoke (62). 6. An arrangement according to any of the preceding Patent Claims 1 - 5, characterised in that the arm (9) is supported by a mounting axle (δ) v/hich is disposed substan¬ tially vertically and one end of v/hich is accommodated in the holder (48) substantially perpendicular thereto, in a stub connection (52), preferably in the region between the said mounting points (55, 56) for the scraper arm (49) in the holder (48), and that the scraper arm (54, 49) bears two abutment stops (77, 78) which are designed to co-act with the holder (48) and restrict the displacement of the arm (54, 49) in the longitudinal direction of the holder (48). 7. An arrangement according to any of the preceding Patent Claims, characterised in that it comprises a con¬ tainer (1) in which the material intended for drying is heated, this container (1) being formed by a preferably closed vessel (1) which is equipped with an inlet aperture (6) for feeding in moist manure, and an aperture (12) for removing the dried product, the said vessel (1) comprising an upper and a lower chamber (3 and 4 respectively) which • are separated by a partition (2) made of thermally conduct- in material, the upper chamber (3) being designed to acco- modate manure while the lower chamber (4) communicates with arrangements (23) for indirectly heating up the manure via the said partition (2), and that a gas outlet hole (21) in the lower chamber (4) communicates with a hot air supply inlet passage (34a) v/hich opens into the said lower chamber (4) in the vicinity of a section (25a) of a tubular element or the like surrounding a burner flame (23a), and that a gas inlet hole (20) is arranged in the lower chamber (4) for the circulation of gas in the latter- (4), the said lowe chamber (4) being divided into preferably two sector-shaped chamber parts (A and B respectively) by means of a wall 'arrangement (15, ^S) which extends from the wall (16) of the said lower chamber (4) in the region between the gas outlet hole and the gas inlet hole (21, 20), separating the from each other, up to a certain distance from the wall (16 of the said lower chamber (4), forming a through-flow open¬ ing (19) between the wall arrangement (18) and the chamber wall (16). 8. An arrangement according to Patent Claim 7, characterised in that, at a distance from the said inlet passage (3^e.) which extends substantially tangentially in the preferably circular lower chamber (4), a burner (23) is connected to a sleeve (34) surrounding the said tubular elemen section (25a) for the burner flame and that the sai tubular element section (25a). is formed by the end of an ai supply pipe (25) into which there opens a fresh air inlet OM (42), and preferably also a gas outlet line (41) from a condenser (37) connected to the upper chamber (3) of the vessel. 9. An arrangement according to either of Patent Claims 7 - 8, characterised in that the gas outlet hole (21) is in communication with the gas inlet hole (20), a gas cir¬ culation device such as a fan (30), for example, preferably being .provided for the circulation of gas in a circuit. 10. An arrangement according to Patent Claim 8, characterised in that the air supply pipe (25) is connected to a heat-exchanger (25) v/hich is connected in turn via a passage (28) to an outflow hole (22) in the lower chamber M

Inventors: ASP LENNART, ASP, LENNART
Applicants: SWEDRIER AB
Application year: 1982
Main classification: F26B25
IPC codes: F26B3, F26B17, F26B25