SE433074B - REACTOR FOR ANAEROBIC ROOTING AND MANUFACTURING OF METANGE GAS FROM SLAM CONTAINING ORGANIC MATERIAL - Google Patents

Description

7909320-9 i l As the methane bacteria multiply slowly, it has beaten, that part of the bacterial mass is returned to the beginning of the process as a graft to streamline gas production. The acid however, the toxic effect is strongest at the inlet end of the reactor.

If the toxicity is eliminated before the inoculation, the methane bacteria can continue their activities without interruption. This can be done using using certain 'reducing' chemicals or by to pre-treat the material with so-called optional bacteria. This conveniently takes place in the pre-treatment department, in which the sludge at the same time can be heated to reaction temperature. The arrangement of such a separate pre-treatment or preheating department however, raises the price of the reactor. Between the different departments pumps and pipes should also be provided, which means technical and increases the risk of oxygen leakage.

The types of reactors used for anaerobic digestion of organic sludge currently usually comprises standing cylinders, which are difficult to divide into sections. There are several of them agitators, pump shafts and other auxiliary equipment caused which carry risks of leakage of either oxygen in the sludge, which interferes with the activity of the methane bacteria, or by methane gas, which poses a risk of explosion. l standing reactors the hydraulic pressure is high, which is disadvantageous for methane bacteria, and in addition the agitation is uneven and demanding a lot of energy or complicated and expensive pumps.

ZS Formerly known are also horizontal reactors (Sierp, Fr., Splittberger, A. and Holthöfer, H., Handbuch der Lebensmittel- chemistry, water and air, part I, Springer-Verlag (1939), p. 327, UE ~ 0S 25 35 750, Fr-A-73¿.738 and FR-A-78l.147). [une I such horizontal reactor is arranged one rotating about a horizontal axis. bar mechanical stirrer. The disadvantage of these reactors has been, that they could not at the same time be provided with partitions and at stirrer attach longitudinal support and other structures. Bristen on support structures has led to the agitator shaft having must be dimensioned unreasonably strong or supported with intermediate horizontal support brackets, which also prevent the installation of all longitudinal, 1 copy pipelines required for graft transport.

Unlike previously known reactor types, intermediate attached to the walls of the reactor of the present invention on the stirrer so that they rotate with it. Thus, partition walls are 40 na no longer in the way of longitudinal structures for raising 7909320-9 of the stirrer strength, whereby the stirrer can be made with a light but at the same time strong construction, and it can in addition with support structures are also provided with completely new longitudinal structures tours, for example a pipe and scraper device for returning a part of the solid seed material sedimented at the outlet end of the reactor to the inlet end of the reactor. Namely, the return device consists of one from one opening near the periphery of the sedimentation compartment partition to any compartment at the inlet end of the container by any intermediate partitions extend, with the stirrer rotating and with its axis an angle-forming tube and a scraper, extending from said opening along the sedimentation compartment bottom and rotates with the stirrer to control it on sediment the bottom of the mentation department sedimented the solid material in in the return pipe. The return pipe can be either main objectively straight or arranged to extend in a helical path near the cylindrical shell of the container.

What is new about the restoration device is that it runs completely within the reactor and that it is arranged to rotate with the stirrer, whereby the rotational movement of the stirrer contributes to the feed of the return sludge from the scraper through the pipe.

In the reactor according to the invention, at least the first the rotating partition be axially movable so that the size the relationship between the first and second departments may change as needed. inloppct for undigested sludge is led into the first the compartment and the outlet opening of the return pipe are located preferably in the second compartment, so that returned inoculum rial does not come into direct contact with fresh and oxygen-rich sludge.

The first partition can be slidable along the shaft and is preferably attached to a device arranged inside the stirrer shaft rod, which extends outside the reactor, so that partitions can be moved axially from time to time from the outside of the reactor.

When the inlet end of the return pipe and the scraper in its elongation is raised from the sludge upon rotation of the mixer, slides the return sludge in the return pipe downwards towards the so-called methane gavdolningen and graft a methane bacterial mass into it. If- the stirrer is preferably stopped in such a position that the scraper and from it accumulated sludge of high dry matter content above the sludge surface. The recycling sludge then slides off 79093 20-9 ZS 40 11 itself from the scraper into the return pipe and further into the methane department. Inside the sedimentation section there is_also preferably in the rear wall of the reactor attached substantially to the reactor. tower longitudinal vertical slats on such height above the bottom of the sedimentation compartment, to the scraper can pass under them. The scraper is arranged to move close the lower edge of the vertical slats, so that the scraper at each lap cuts a sheet of the sediment sinking between the slats mented the sludge cake without disturbing the sedimentation.

In addition, the stirrer preferably has a plurality of i in the vicinity of the reactor jacket arranged in the axial direction stretched and substantially over the entire length of the reactor with the exception of take for the sedimentation department extending wings, which either attached to the partitions or passing through these if a partition is axially displaceable. When stirring The rotation of the tube moves along the inner wall of the container, at the inner wall is kept clean, which facilitates heat transfer from a possible heat source arranged on the outside of the jacket. In addition the wings rise above the surface of the sludge in the reactor and extinguish effectively accumulated foam on the surface of the sludge, when they are lowered again below the sludge surface. There are no agitators in the sedimentation department ~ wings and they can also be omitted from one or more of the others departments. The agitator blades are usually attached in between the walls, but if the partition is axially displaceable, the the pipe wings arranged to pass through corresponding openings in the sliding partition.

In the partitions may be openings, through which the sludge can pass from one department to another. These openings are. however, not indispensable, in that sludge can pass even through the gaps between the mill walls and the reactor jacket.

The invention is described in more detail below with reference _to the attached drawing, there fig. 1 shows a vertical longitudinal section through an embodiment of the invention, Fig. 2 is a section along line A-A in Fig. 1, Fig. 3 is a section along line B-B in Fig. 1 and fig. 4 shows an end view of it in fig. 1 shows the outlet of the reactor End.

In the drawing, 1 denotes a reactor's cylindrical jacket.

Inside the horizontal cylindrical jacket 1 is arranged one 40 7909320-9 central shaft 2, which at the outlet end of the reactor extends outside the end of the reactor 3 and is connected there to a drive device 4, by means of which the shaft 2 rotates. Shaft 2 is at each end stored in layers in the reactor ends 3 and 5, of which layers it in end 3 is sealed.

In the end S of the reactor there is an inlet 6 for sludge. lnloppet 6 opens into the reactor substantially in the middle portion of the gable 5, so that the inlet completely surrounds the bearing 2 of the shaft 2 in the end wall 5, the bearing does not need to be sealed. At the opposite end of the reactor there is an outlet 7 for digested sludge, which opens to the reactor at a point slightly above the shaft 2 bushing bearings.

As can be seen in more detail in Figs. 1 and 4, can be found in outlet 7 a height-adjustable dam slide 8, by means of which sludge level S in the reactor is adjustable. At the outlet end of the reactor is located in addition, a drain pipe 9 for flue gas, which is arranged at it highest point of the cylindrical shell 1, so that its opening is located above the sludge surface S. In the reactor there are also some axially spaced apart at the shaft 2 attached circular partitions 10, which in addition to the first partition count in the direction of flow are stationary. This first partition is axially displaceable by means of one inside the shaft 2 of the stirrer extending and outside the reactor's extending rod 11, which is attached to the first partition with the help of a on shaft Z slides sleeve.

Between the partitions 10 are further arranged three stirring tubes wings 13 in the vicinity of the cylindrical wall 1, so that the wings 13 are located in the corners of an equilateral triangle. In the last of the reactor department, the so-called sedimentation department 14, exists no agitator wings 13. On the other hand, the wings 13 extend through the axially displaceable first partition wall 10 and into it the first zone, where their ends are interconnected by stng IS. The agitator vanes 13 extend so close to that of the cylindrical jacket In the inner wall, that when the stirrer rotates, they pour the inner wall clean and in addition they have an effective extinguishing effect on the foam, which formed on the surface of the sludge (S), as they pass down below the surface. The also provides efficient agitation.

In addition, the partitions 10 have one or more openings ll, through which the sludge can flow from one compartment to another Other. In addition, the sludge can flow through the annular gap between the inner periphery of the partitions and the cylindrical shell I 'inner wall.

ZS p 4: 1 40 7909320-9 6 Reference numeral 17 denotes a return pipe. The return pipe 17 extends from an opening 20 in the vicinity of the periphery of the last partition wall 10 by intermediate partitions walls to the second department. Tube 17 passes through intermediate partitions 10.

In addition, a scraper is attached to the last partition wall 10 18, which extends from this partition wall into the sedimentation compartment 14 in the immediate vicinity of the cylindrical jacket 1.

The scraper 18 has the shape of a gutter, the mouth of which is directed forward ate in the direction of rotation, so that the Scraper 18 in its lower position filled with material deposited in the sedimentation compartment 14 bottom and bring it with you. The inlet pipe of the return pipe 17 In opening 20 is located at the bottom of the gutter-shaped scraper 18, so that material which has entered the scraper 18 flows through the opening into the return pipe 17 and thereby on to the other department. The stirrer is preferably stopped when the scraper 18 is finds itself in its upper position, so that in the existing return material under the influence of gravity flows into the return tube 17.

In the sedimentation compartment 14 a wide is further arranged attached to the reactor end 3 of a lamella package 19 comprising a number vertically spaced vertical, in the length of the reactor direction-directed slats, which have the task of damping in sedimentation compartment 14 any occurring currents and facilitate the sedimentation of the solid material from the sludge.

The lamella package 19 is arranged at such a height above the sediment the bottom of the compartment 14, that the scraper 18 can unhindered pass between the jacket 1 and the lamella package 19 taking between the slats sedimented solid material. _ Rot sludge, in which any reducing or other chemicals, are fed either intermittently or continuously through the inlet 6 in the reactor. The sludge is stirred and heated in the first section; which can be called heating department, in the second department shall be appointed from the tube 17 coming methane bacterial mass, whereby the digestion begins and in the second, third and fourth compartments methane is formed, which exits through the pipe 9 in the upper part of the reactor and is recovered.

In the last section, i.e. the sedimentation section 14, it sinks the solid of the sludge to the bottom of the sedimentation compartment 14 and some of this sedimented sludge is returned by means of 7909320-9 7 The scraper 18 and the return pipe 17 to the second compartment.

Finally, the digested sludge flows out into the outlet 7, in which the sludge level in the reactor is regulated with the dam slide 8. The stirrer rotates either continuously or and preferably inter- middle, so that the scraper 18 always stays in its upper position, so that the sludge carried by the action of gravity flows into the return tube 17.

Claims (5)

7909320-9 * 3 PÅTÉNIÉBÅY l. Reactor for anaerobic digestion and production of methane gas from sludge containing organic material, comprising a substantially horizontal cylindrical container ill, in which is arranged around an equally substantially horizontal shaft ll rotor container. one end has an inlet (bl for feeding sludge sludge into the container and at the other end an outlet (7l for removing rotten sludge from the container and in the upper part an outlet pipe (9bl for collecting methane gas), l partitions extending at the stirrer at mutually axial intervals loaded partitions llül, connections extend to the vicinity of the cylindrical jacket and rotate with the stirrer.Which partitions divide the heater in its longitudinal direction into compartments, the last of which constitutes a sedimentation compartment «l4l , and by means for returning a part of the solid material sedimented in the sedimentation compartment to another compartment closer the inlet end of the container, which return means are constituted by a tube 117), which from an opening near the periphery of the partition wall of the sedimentation section extends through any intermediate partitions to said compartment closer to the inlet end of the container and rotates with the stirrer and forms an axis and (18), which extends from the opening in the partition wall of the sedimentation compartment along the bottom of the sedimentation compartment and rotates with the stirrer to conduct the solid material sedimented to the bottom of the sedimentation compartment to the return pipe. 2. A reactor according to claim 1, characterized in that the inlet and outlet openings of the return pipe are inherently offset seen in the axial direction of the stirrer and are preferably located on opposite sides of the shaft of the stirrer. 3. A reactor according to claim 1, characterized in that the return pipe is arranged to run along a substantially helical path in the vicinity of the cylindrical shell of the container. 4. A reactor according to claim 1, ¿or 3, characterized in that at least the first partition wall is axially displaceable. 5. A reactor according to claim 3, characterized in that at least the first partition wall is fastened in a sleeve (12) slidable on the shaft of the driver, which in turn is connected 7909320-9. q mcd un inn-s i -Jnirörarcns ax-fl liiirlíšisziiiilu »ch ulaniêii 'rcakturr sig strückandc back and forth movable fi tang Klin. . nch i lüngdriktningun Förlöpandc lzuncllzrr. 7. Rcaktox 'according to any of you förcgnexiclc: patøntkravcn, k ii nnctc L' knad of ntt plural in närhofcii of ruaktorns iimntL-l pa omrörarcn zmurdnadi »limgstrširkta vingar, which striirkiri- siy n 'icl lu ivrz' ~ - hola líinig! mL-d undzln ~ l ag lm '* avd in-.vnl at. iif-nsav-JL ln 1 ngvn, vi i La: m1 iiigcii En i íisl 'adc nu .nul lrmxvšiggcxa ullršr passerar lgcnnin -.1ciis ~. ~ 1nnii.i, da fnul lanvšigguii iir .1_ \' icl ll lör lör. .