Patent Application
20120325642
The present invention relates to an improvement of a carbonizing apparatus that recycles an organic treatment object to be treated, such as a waste tire, wood, and other wastes, into oil, gas, a carbonized product, etc. by dry distillation.
Dry distillation gas is generated when an organic treatment object to be treated, such as rubber or plastics, is decomposed by heating. When the dry distillation gas passes through a cooling device, oil is separated therefrom. In the cooling device, surplus gas containing a low-boiling-point component that is not liquefied is generated. This surplus gas has odor, and therefore, cannot be directly discharged into the air. For this reason, in conventional carbonizing apparatuses, surplus gas is burnt in an odor and smoke eliminating device (combustion furnace) to be detoxified and deodorized.
In such a conventional carbonizing apparatus, a plurality of treatment chambers, which are closed by shielding doors, are arranged in series, and a carry-in step, a preheating step, a thermal decomposition (dry distillation) step, a cooling step, a carry-out step, etc. are performed in order in the treatment chambers (see Patent Literature 1).
In a system disclosed in Patent Literature 1, first and second preliminary chambers are provided on an upstream side of a plurality of heating chambers. In the second preliminary chamber adjacent to the first heating chamber, a treatment object in a container is preheated by a heater on a predetermined temperature condition. By thus preheating the treatment object before the treatment objects enters the first heating chamber, heating efficiency in the first heating chamber is enhanced.
However, in the carbonizing apparatus disclosed in Patent Literature 1, since preheating is performed in the second preliminary chamber, dry distillation gas may be generated from the treatment object according to the type of the treatment object. If dry distillation gas is generated and is exhausted outside through the first preliminary chamber, even a risk of explosion exists. This is significantly undesirable. That is, in terms of safety, the system needs to completely eliminate at least the risk of explosion, even if the heating efficiency is reduced somewhat.
The present invention has been made in view of the above-described problems, and an object of the invention is to provide a carbonizing apparatus that can completely eliminate the possibility that dry distillation gas will leak out of the apparatus and explode.
A carbonizing apparatus according to the present invention includes: a heating chamber that thermally decomposes a treatment object by heating; a preliminary chamber through which the treatment object is carried from an outside into the heating chamber in a state in which the heating chamber is substantially shielded from the outside, the preliminary chamber being provided between the heating chamber and the outside; a plurality of cooling chambers in which the treatment object is treated after thermal decomposition; shielding doors that close the preliminary chamber, the heating chamber, and the cooling chambers arranged in series; a transport means that transports the treatment object while opening and closing the shielding doors; and exhaust pipes through which gas discharged from the preliminary chamber, the heating chamber, and the cooling chambers is exhausted. The treatment object is carbonized while being sequentially passed through the preliminary chamber, the heating chamber, and the cooling chambers. The preliminary chamber is kept unheated.
The transport means includes a container that receives the treatment object, and a conveyor that transports the container.
3. The present invention carbonizes a treatment object received in a container by passing the treatment object through at least a heating chamber.
The container includes a box-shaped body formed by an open upper face, a bottom portion, and side wall portions provided on all sides, and a treatment-object set portion inclined with respect to the bottom portion such that the treatment object is set on the treatment-object set portion.
One of a pair of faces of the side wall portions has a slot through which the treatment object is fed in the treatment-object set portion, and the other of the pair of faces of the side wall portions has a vent hole.
A stepped portion that prevents the fed treatment object from falling off through the vent hole is provided between the vent hole and the treatment-object set portion.
An embodiment in which the present invention is applied to a carbonizing apparatus for carbonizing an organic waste material by thermal decomposition will be described below with reference to the attached drawings.
As illustrated in
As shown by the arrow in
The setting numbers of preliminary chambers 11 and 12 and treatment chambers 21 to 24 and 31 to 33 are not limited thereto, and may be increased or decreased, for example, according to the required processing performance. For example, instead of four heating chambers, that is, the first to fourth heating chambers 21 to 24, three or less, or five or more heating chambers may be provided.
The carbonizing apparatus includes, as a transport means, a container 100 that receives a treatment object, and a conveyor that transports the container 100. The conveyor extends through the interiors and exteriors of the treatment chambers 11, 12, 21 to 24, and 31 to 33, and transports the container 100 in a flow direction shown by the arrow (a substantially horizontal direction).
The carbonizing apparatus includes ten shielding doors 5 serving as means for opening and closing the preliminary chambers 11 and 12 and the treatment chambers 21 to 24 and 31 to 33. The shielding doors 5 are moved up and down by an unillustrated driving mechanism. When the shielding doors 5 are pulled up to predetermined opening positions, they open doorways of the preliminary chambers 11 and 12 and the treatment chambers 21 to 24 and 31 to 33 so that the container 100 transported by the conveyor can pass therethrough. In contrast, when the shielding doors 5 are pulled down to predetermined closing positions, they hermetically close the preliminary chambers 11 and 12 and the treatment chambers 21 to 24 and 31 to 33.
Each of the preliminary chambers 11 and 12 and the treatment chambers 21 to 24 and 31 to 33 is provided with a nitrogen-gas injection pipe 2 through which nitrogen gas is injected, and an exhaust pipe 3 through which gas is exhausted from the chamber. A low oxygen concentration atmosphere is produced by nitrogen substitution in which nitrogen gas is injected through the nitrogen-gas injection pipe 2 and gas in the chamber is forcedly exhausted through the exhaust pipe 3.
The first to fourth heating chambers 21 to 24 are arranged side by side at the center in the flow direction of the carbonizing procedure. In the first to fourth heating chambers 21 to 24, a treatment object in the container 100 is heated by an unillustrated heater on a predetermined temperature condition (e.g., about 360 to 450° C.), and the treatment object is carbonized by thermal decomposition (dry distillation) without being burnt in the low oxygen concentration atmosphere. In the first to fourth heating chambers 21 to 24, high-calorie dry distillation gas is generated from the treatment object by this thermal decomposition, and gas exhausted from the first to fourth heating chambers 21 to 24 to the exhaust pipes 3 by nitrogen substitution has a high concentration of combustible components.
In this way, carbonization for thermally decomposing the treatment object is performed in the first to fourth heating chambers 21 to 24. In contrast, in the embodiment, the preliminary chambers 11 and 12 are kept unheated, and therefore, thermal decomposition of the treatment object is not performed in the preliminary chambers 11 and 12. As a result, dry distillation gas is not generated from the treatment object.
The second preliminary chamber 12 is provided between the first heating chamber 21 and the first heating chamber 21, and the container 100 is transported from the second preliminary chamber 12 to the first heating chamber 21 while opening and closing the shielding door 5. In the second preliminary chamber 12, nitrogen substitution is performed.
Since the second preliminary chamber 12 is kept unheated, a state in which no dry distillation gas is generated from the treatment object is maintained. However, when the shielding door 5 is opened and closed, dry distillation gas in the adjacent first heating chamber 21 flows into the second preliminary chamber 12, so that gas exhausted from the second preliminary chamber 12 to the exhaust pipe 3 by nitrogen substitution has a somewhat high concentration of combustible components.
The first preliminary chamber 11 is provided on the most upstream side in the flow direction of the carbonizing procedure. While the shielding door 5 is opened and closed, the container 100 is carried in the first preliminary chamber 11, where nitrogen substitution is performed.
The first preliminary chamber 11 is provided on an upstream side of the second preliminary chamber 12. While the shielding door 5 is opened and closed, the container 100 is carried from the first preliminary chamber 11 into the second preliminary chamber 12. In the first preliminary chamber 11, dry distillation gas is not generated from the treatment object because thermal decomposition of the treatment object is not performed. Although a small amount of dry distillation gas remaining in the adjacent second preliminary chamber 12 flows in the first preliminary chamber 11 when the shielding door 5 is opened and closed, gas exhausted from the first preliminary chamber 11 to the exhaust pipe 3 by nitrogen substitution has a low concentration of combustible components.
On a downstream side of the first to fourth heating chambers 21 to 24, the first to third cooling chambers 31 to 33 are provided as cooling chambers where treatment after thermal decomposition is performed.
The first cooling chamber 31 is provided on a downstream side of the fourth heating chamber 24. While the shielding door 5 is opened and closed, the container 100 is carried from the fourth heating chamber 24 into the first cooling chamber 31. In the first cooling chamber 31, a first cooling step for the treatment object is performed. Dry distillation gas is generated from the treatment object by residual heat, and dry distillation gas flows from the adjacent fourth heating chamber 24 in the first cooling chamber 31 when the shielding door 5 is opened and closed, so that gas exhausted from the first cooling chamber 31 to the exhaust pipe 3 has a somewhat high concentration of combustible components.
The second cooling chamber 32 is provided on a downstream side of the first cooling chamber 31. While the shielding door 5 thereof is opened and closed, the container 100 is carried from the first cooling chamber 31 into the second cooling chamber 32. In the second cooling chamber 32, a second cooling step for the treatment object is performed, and little dry distillation gas is generated from the treatment object by residual heat. Although a small amount of dry distillation gas remaining in the adjacent first cooling chamber 31 flows into the second cooling chamber 32 when the shielding door 5 is opened and closed, gas exhausted from the second cooling chamber 32 to the exhaust pipe 3 by nitrogen substitution has a low concentration of combustible components.
The third cooling chamber 33 is provided on a downstream side of the second cooling chamber 32. While the shielding door 5 is opened and closed, the container 100 is carried from the second cooling chamber 32 into the third cooling chamber 33. In the third cooling chamber 33, a third cooling step for the treatment object is performed, and little distillation gas is generated from the treatment object by residual heat. Although a very small amount of dry distillation gas remaining in the adjacent second cooling chamber 32 flows into the third cooling chamber 33 when the shielding door 5 is opened and closed, gas exhausted from the third cooling chamber 33 to the exhaust pipe 3 by nitrogen substitution has a low concentration of combustible components.
The third cooling chamber 33 is provided on the most downstream side in the flow direction of the carbonizing procedure. While the shielding door 5 thereof is opened and closed, the container 100 is carried from the third cooling chamber 33 to the outside.
In the first to fourth heating chambers 21 to 24, high-calorie dry distillation gas is generated from the treatment object during thermal decomposition. This dry distillation gas contains a lot of combustible hydrocarbon components. When the dry distillation gas passes through the exhaust pipes 3 and is heated by cooling devices 6, the combustible components are liquefied and combustible oil is recovered. However, surplus gas passing through the cooling devices 6 contains a low-boiling-point combustible component that is not liquefied. For example, the surplus gas has a calorie of about 1000 to 10000 kcal/m3.
Since the second preliminary chamber 12 is kept unheated, no dry distillation gas is generated from the treatment object. However, when the shielding door 5 is opened and closed, dry distillation gas in the adjacent first heating chamber 21 flows into the second preliminary chamber 12. Thus, when gas exhausted from the second preliminary chamber 12 through the exhaust pipe 3 is cooled by a cooling device 6, combustible components are liquefied and combustible oil is recovered. Surplus gas passing through the cooling device 6 contains some low-boiling-point combustible components that are not liquefied.
In the first cooling chamber 31, dry distillation gas is generated by residual heat during cooling of the treatment object, and dry distillation gas in the adjacent fourth heating chamber 24 flows in the first cooling chamber 31 when the shielding door 5 is opened and closed. Thus, when gas exhausted from the first cooling chamber 31 through the exhaust pipe 3 and is cooled by a cooling device 6, combustible components are liquefied and combustible oil is recovered. Surplus gas passing through the cooling device 6 contains some low-boiling-point combustible components that are not liquefied.
As equipment for treating gas exhausted from the treatment chambers 11, 32, and 33, a safety device 8 for preventing backflow of the gas and a first odor and smoke eliminating device 51 for burning the gas are provided.
As equipment for treating gas exhausted from the treatment chambers 12, 21 to 24, and 31, cooling devices 6 for separating oil by cooling the gas, oil recovery devices 7 for recovering oil contained in surplus gas, safety devices 8 and 9 for preventing backflow of the gas, and second odor and smoke eliminating devices 61 are provided.
While two second odor and smoke eliminating devices 61 and one first odor and smoke eliminating device 51 are provided in the embodiment, alternatively, the setting number of odor and smoke eliminating devices may be increased or decreased, for example, according to the required processing performance.
Gas containing few combustible components and exhausted from the first preliminary chamber 11, the second cooling chamber 32, and the third cooling chamber 33 passes through a first exhaust passage 50, and is introduced into the first odor and smoke eliminating device 51, where odor and smoke of the gas are eliminated by a high-temperature atmosphere. Then, the gas is exhausted outside from a heat exhaust pipe 55 of the first odor and smoke eliminating device 51.
The exhaust pipes 3 extending from the first preliminary chamber 11, the second cooling chamber 32, and the third cooling chamber 33 are connected to one safety device 8, and gas passing through the safety device 8 is guided to the first odor and smoke eliminating device 51 through the first exhaust passage 50. That is, in a path through which gas from the first preliminary chamber 11, the second cooling chamber 32, and the third cooling chamber 33 is guided to the first odor and smoke eliminating device 51, a cooling device and an oil recovery device are not provided.
The safety device 8 has a structure similar to that of below-described safety devices 9 (see
A suction fan 56 is provided in the first exhaust passage 50, and gas is sent into the first odor and smoke eliminating device 51 through the suction fan 56.
The first odor and smoke eliminating device 51 includes a combustion furnace 54 where gas is retained, a burner 53 facing the interior of the combustion furnace 54 to maintain the temperature in the combustion furnace, and a heat exhaust pipe 55 through which gas burnt in the combustion furnace 54 is exhausted outside.
The burner 53 for maintaining the temperature in the combustion furnace is provided near an exit of the combustion furnace 54. The burner 53 burns supplied fuel in the combustion furnace 54 to maintain a predetermined temperature (e.g., about 800° C.) in the combustion furnace 54.
In the first odor and smoke eliminating device 51, the combustion furnace 54 has a capacity such that a predetermined gas retention time can be obtained. While gas (dry distillation gas+nitrogen) passes through a high-temperature atmosphere in the combustion furnace 54, odor is efficiently eliminated from the gas.
Gas containing a lot of combustible components and exhausted from the second preliminary chamber 12, the first to fourth heating chambers 21 to 24, and the first cooling chamber 31 passes through second exhaust passages 60, and is introduced into the second odor and smoke eliminating devices 61, where it is burnt. After that, odor and smoke are eliminated from the gas in a high-temperature atmosphere, and is exhausted outside from heat exhaust pipes 65 of the second odor and smoke eliminating devices 61.
In the exhaust pipes 3 through which gas is exhausted from the second preliminary chamber 12, the first to fourth heating chambers 21 to 24, and the first cooling chamber 31, cooling devices 6, oil recovery devices 7, and safety devices 9 are arranged in series.
Dry distillation gas exhausted from the second preliminary chamber 12, the first to fourth heating chambers 21 to 24, and the first cooling chamber 31 through the exhaust pipes 3 is cooled by the cooling devices 6, so that oil contained in the dry distillation gas is liquefied.
Each of the cooling devices 6 includes a group of cooling water pipes through which cooling water flows, and a heat exchanging unit where cooling water circulates around a gas tube through which dry distillation gas passes. The cooling device 6 cools the dry distillation gas by these components, and recovers sludge, such as liquefied oil and sulfur contents, from the dry distillation gas.
The oil liquefied in the cooling devices 6 is sent to a primary oil tank 41 through pipes 15, oil in the primary oil tank 41 is sent to three secondary oil tanks (oil tanks) 42 through pipes 16 and oil transfer pumps 26, and oil in the secondary oil tanks 42 is sent to a clean oil tank 43 through pipes 17 and oil transfer pumps 27, and is stored in the clean oil tank 43.
An overflow receiving tank 44 is provided to store oil overflowing from the primary oil tank 41 and the secondary oil tanks 42 and 43. Oil overflowing from the primary oil tank 41 is sent to the overflow receiving tank 44 through a pipe 35, oil overflowing from the secondary oil tanks 42 is sent to the overflow receiving tank 44 through pipes 36, and oil overflowing from the clean oil tank 43 is sent to the overflow receiving tank 44 through a pipe 19. Oil in the overflow receiving tank 44 is returned to the primary oil tank 41 through a pipe 37 and an oil transfer pump 38.
Fuel oil, such as heavy oil A, is stored in an underground tank 46 and an indoor tank 47. Oil overflowing the indoor tank 47 is sent to the underground tank 46 through a pipe 49. Oil in the underground tank 46 is returned to the indoor tank 47 via an oil transfer pump 48.
Oil in the indoor tank 47 and oil in the clean oil tank (fuel tank) 43 are sent to combustion furnace burners 62 and 63 in the second odor and smoke eliminating devices 61 and the burner 53 in the first odor and smoke eliminating device 51 through a fuel supply passage 18. The indoor tank 47 is connected to the fuel supply passage 18 via a switch valve 58, and the clean oil tank (fuel tank) 43 is connected to the fuel supply passage 18 via a switch valve 59.
At the start of dry distillation (a state in which clean oil is not stored in the clean oil tank 43) and when clean oil runs out in the clean oil tank 43 during dry distillation, the switch valve 59 is closed and the switch valve 58 is opened to supply heavy oil from the indoor tank 47 to the combustion furnace burners 53, 62, and 63 through the fuel supply passage 18. When a sufficient amount of clean oil is stored in the clean oil tank 43, the switch valve 59 is opened and the switch valve 58 is closed to supply the clean oil from the clean oil tank 43 to the combustion furnace burners 53, 62, and 63 through the fuel supply passage 18.
A wastewater tank 45 is provided to store wastewater taken out of the safety devices 9 and the safety device 8. Into the wastewater tank 45, wastewater from the safety devices 9 is guided through a pipe 67, and wastewater from the safety device 8 is guided through a pipe 68.
The combustion furnace burners 53, 62, and 63 are of a water combine combustion type that mixes and burns oil supplied from the clean oil tank 43 or the indoor tank 47 through the fuel supply passage 18 and flow-rate adjusting valves 57 and wastewater supplied from the wastewater tank 45 through a wastewater supply passage 69 and flow-rate adjusting valves 20. The amounts of fuel oil and water supplied to the combustion furnace burners 53, 62, and 63 are adjusted by the openings of the flow-rate adjusting valves 57 and the flow-rate adjusting valves 20 so that the oil and the water are mixed at a proper mixing ratio.
Surplus gas passing through the cooling devices 6 is sent to the oil recovery devices 7, where oil and sludge contained in the surplus gas are recovered. The oil and sludge recovered by the oil recovery devices 7 are sent to the primary oil tank 41 through pipes 10.
As will be described below, the oil recovery devices 7 store oil adsorbing liquid, and pass surplus gas in the oil adsorbing liquid. When the oil contained in the surplus gas is liquefied by contact with the oil adsorbing liquid, and is then recovered. Surplus gas emerging on the oil adsorbing liquid in the oil recovery devices 7 is sent to the safety devices 9 through pipes 8.
As illustrated in
The number of gas chambers 76 to 78 and the number of gas inflow pipes 71 to 73 are not limited thereto, and are arbitrarily set, for example, according to the required processing performance.
Surplus passing through the cooling device 6 flows into the oil adsorbing liquid in the oil adsorbing liquid tank 75 through the gas inflow pipe 71. The surplus gas emerging in the gas chamber 76 above the surface of the oil adsorbing liquid flows into the oil adsorbing liquid in the oil adsorbing liquid tank 75 through the gas inflow pipe 72, the surplus gas emerging in the gas chamber 77 above the oil adsorbing liquid flows into the oil adsorbing liquid in the oil adsorbing liquid tank 75 through the gas inflow pipe 73, and the surplus gas emerging in the gas chamber 78 above the surface of the oil adsorbing liquid flows out through a gas outflow pipe 85. The surplus gas coming out of the oil recovery device 7 through the gas outflow pipe 85 is guided into the safety device 9 through a surplus-gas introducing pipe 85.
The oil adsorbing liquid tank 75 includes gas-permeable plates 81 serving as a bubble dividing means 80 through which bubbles of the surplus gas rising after flowing out from the gas inflow pipes 71 to 73 pass to be divided into fine bubbles. The surplus gas flowing out in the form of large bubbles from the gas inflow pipes 71 to 73 passes through the gas-permeable plates 81 while rising in the oil adsorbing liquid, so that the large bubbles are turned into fine bubbles. This urges oil contained in the surplus gas to be liquefied by contact with the oil adsorbing liquid and to be mixed in the oil adsorbing liquid.
The gas-permeable plates 81 have a lot of small holes opening at predetermined intervals. The bubble dividing means 80 is not limited to the gas-permeable plates 81, and, for example, may be formed by a mesh material.
Three gas-permeable plates 81 are arranged in the up-down direction. Lower ends of the gas inflow pipes 71 to 73 extend through the gas-permeable plates 81. The number of gas-permeable plates 81 is not limited thereto, and is arbitrarily set, for example, according to the required processing performance.
A gas intake port 82 shaped like a cutout is provided in an upper portion of an open end of each of the gas inflow pipes 72 and 73 at the gas chamber 77, and an oil-mist collision plate 83 is fixed to oppose the gas intake port 82. Thus, gas in the gas chamber 77 flows from the gas intake port 82 into a relay pipe 88 beyond the oil-mist collision plate 83. When the oil adsorbing liquid in the oil adsorbing liquid tank 75 bubbles and oil mist is produced in the gas chamber 77, the oil mist is urged to be liquefied by colliding with the oil-mist collision plate 83.
A disc-shaped oil-mist collision plate 86 is provided to oppose an open end of the gas outflow pipe 85 in the gas chamber 77. Thus, gas in the gas chamber 77 flows into the gas outflow pipe 85 while bypassing the oil-mist collision plate 86. When the oil adsorbing liquid in the oil adsorbing liquid tank 75 bubbles and oil mist is produced in the gas chamber 77, this oil mist is urged to be liquefied by colliding with the oil-mist collision plate 86.
In a lower portion of the oil adsorbing liquid tank 75, an exit 87 is opened, and a valve 89 is provided to open and close the exit 87. The oil adsorbing liquid tank 75 has a bottom portion 88 that slopes toward the exit 87. Sludge contained in the oil adsorbing liquid is collected at the exit 87 through the bottom portion 88 by gravity. When the valve 89 is opened, the sludge is sent together with the oil adsorbing liquid to the primary oil tank 41 through the pipe 10.
To the oil adsorbing liquid tank 75, heavy oil A is supplied as oil adsorbing liquid from the indoor tank 47 through a pipe 91 via an oil transfer pump 92. The oil adsorbing liquid tank 75 includes a liquid level gauge (not illustrated) which detects the liquid surface level of the oil adsorbing liquid. When the detected liquid surface level is lower than a predetermined value, a valve 90 is opened to supply heavy oil A from the indoor tank 47 to the oil adsorbing liquid tank 75.
Heavy oil A is used as oil adsorbing liquid. It was confirmed by experiment that heavy oil A could obtain a viscosity suited to liquid for entrapping bubbles of surplus gas and could provide an oil recovery rate higher than that of light oil or the like having a lower viscosity.
The oil adsorbing liquid is not limited to heavy oil A, and it is conceivable to use another fuel oil or water. However, when water is used as oil adsorbing liquid, an oil-water separator or the like is needed to recover oil floating on the water.
Oil adsorbing liquid overflowing from the oil adsorbing liquid tank 75 flows out from an exhaust pipe 95, and is sent to the primary oil tank 41 through the pipe 15.
Surplus gas passing through the oil recovery device 7 is sent to the second odor and smoke eliminating device 61 through the safety device 9, and is burnt in the second odor and smoke eliminating device 61.
Water is stored in the safety device 9. This water blocks the flow of gas that flows back from the second odor and smoke eliminating device 61 through the pipe 50. Since the water in the safety device 9 is contaminated by the passage of surplus gas, it is periodically exhausted to the wastewater tank 45 through the pipe 67.
As illustrated in
The water tank 93 of the safety device 9 stores water supplied through a pipe 68. Discharged water overflowing from the water tank 93 flows into the wastewater tank 45 through the pipe 67. During maintenance, the water is drained from the safety device 9 with a valve 39 being opened.
Sludge is deposited from dry distillation gas flowing through the cooling device 6 and the oil recovery device 7. This sludge is sent together with liquefied oil to the primary oil tank 41 through the pipe 15, and is collected into the corresponding secondary oil tank 42 through the pipe 16.
Each secondary oil tank 42 is provided with an oil circulation circuit 96 that circulates oil stored therein. In the oil circulation circuit 96, a centrifugal separator 97 is provided to separate and remove sludge and the like contained in the oil. The oil circulation circuit 96 is formed by a plurality of pipes that communicate between the secondary oil tank 42 and the centrifugal separator 97. Oil in the secondary oil tank 42 is sucked into a pump of the centrifugal separator 97 through one of the pipes, and oil flowing out of the centrifugal separator 97 flows to the secondary oil tank 42 through the other pipe. The centrifugal separator 97 separates sludge from the oil circulating therein by centrifugal force. After such a sludge separating and removing process for separating sludge is finished, the oil transfer pump 27 is driven to send and collect the oil in the secondary oil tank 42 into the clean oil tank 43 through the pipe 17.
A clean-oil circulation circuit 99 is provided to circulate the oil in the clean oil tank 43 via a circulation pump 98. A suction port of the clean-oil circulation circuit 99 is connected to a lower portion of the clean oil tank 43. When the oil in the clean oil tank 43 is circulated in the clean-oil circulation circuit 99 by driving the circulation pump 98, it is stirred so that a tar substance contained in the oil of the clean oil tank 43 does not precipitate. Thus, the tar substance is uniformly mixed in the oil to be sent from the clean oil tank 43 to the combustion furnace burners 62, 63, and 53 through the fuel supply passage 18, and is burnt together with the oil in the combustion furnace burners 62, 63, and 53.
Suction fans 66 are provided in the second exhaust passages 60, and gas is sent into the second odor and smoke eliminating devices 61 via the suction fans 66.
Each of the second odor and smoke eliminating devices 61 includes a combustion furnace 64 in which gas is retained, a combustible-gas ignition small-capacity burner 62 facing the interior of the combustion furnace 64, a large-capacity burner 63 for maintaining the temperature in the combustion furnace, and a heat exhaust pipe 65 that exhausts, to the outside, gas burnt in the combustion furnace 64.
The combustible-gas ignition small-capacity burner 62 is provided near an entrance of the combustion furnace 64. The small-capacity burner 62 burns supplied fuel in the combustion furnace 64, and ignites a combustible component contained in the gas flowing into the combustion furnace 64.
The large-capacity burner 63 for maintaining the temperature in the combustion furnace is provided near an exit of the combustion furnace 64, and burns supplied fuel in the combustion furnace 64 so as to maintain a predetermined temperature (e.g., about 800° C.) or more in the combustion furnace 64.
The second odor and smoke eliminating device 61 burns a combustible component in gas (dry distillation gas+nitrogen) to detoxify the gas and to eliminate odor from the gas, and secures the capacity of the combustion furnace 64 so that the temperature in the combustion furnace 64 does not rise above a permitted value (e.g., one thousand and several hundred degrees Celsius) with combustion of the combustible component in the gas. In the combustion furnace 64, abnormal combustion is prevented, and explosion is prevented.
Next, a description will be given of the container 100 used in the carbonizing apparatus of the present invention.
The container 100 includes a box-shaped body 102 having an open upper face 103, a bottom portion 104, and side wall portions 105 provided on all sides, and a plurality of treatment-object set portions 110 which are inclined with respect to the bottom portion 104 and which receive treatment objects.
One face 106 of a pair of faces of the side wall portions 105 has slots 112 through which treatment objects are fed into the treatment-object set portions 110, and the other face 107 of the pair of faces of the side wall portions 105 has a plurality of vent holes 114.
Between the vent holes 114 and surfaces of the treatment-object set portions 110 on which treatment objects are placed, stepped portions 116 are provided corresponding to the treatment-object set portions 110 to prevent the fed treatment objects from falling off through the vent holes 114.
The treatment-object set portions 110 are inclined to slope downward from the slots 112 side toward the vent holes 114. The interval between the treatment-object set portions 110 may be arbitrarily set, for example, according to the size or usage of treatment objects, and the treatment-object set portions 110 may be attached in various manners, for example, by fitting or by integral formation. Further, the treatment-object set portions 110 can be variously modified without departing from the object of the present invention, for example, the treatment-object set portions 110 may be formed of a material having high thermal conductivity, or a heater or the like may be set in the treatment-object set portions 110.
In general, in a container having no treatment-object set portions 110, treatment objects fed in the container are heaped up into a mountain, and the heat transfer area, that is, the contact area between the treatment objects and a low oxygen concentration atmosphere (nitrogen atmosphere) for transferring heat from a heater is small. Hence, heat is not sufficiently transferred into the fed treatment objects. For this reason, in such a container having no treatment-object set portions 110, it is necessary to reduce treatment objects to be fed into the container or to manually level the treatment objects.
However, in the container 100 having the above-described structure, treatment objects are substantially uniformly leveled along the inclination of the treatment-object set portions 110 by being simply fed from the slots 112. This allows heat of the heater to be efficiently transferred to the treatment objects.
The vent holes 114 provided in the other face 107 of the pair of faces of the side wall portions 105, which faces the one face 106 of the pair of faces of the side wall portions 105, allow the low oxygen concentration atmosphere (nitrogen atmosphere) to pass between the slots 112 and the vent holes 114. Hence, the treatment objects are heated efficiently.
Further, the stepped portions 116 provided on the vent holes 114 side can not only prevent the treatment objects from falling off through the vent holes 114 when being fed, but also prevent the treatment objects, which are thermally decomposed and fluidized by heating, from flowing out of the container 100 and leaking to a driving unit for the device, such as the conveyor for conveying the container 100, and to other units in the carbonizing apparatus of the invention.
Next, a description will be given of another container 200 used in the carbonizing apparatus of the present invention.
The container 200 includes a box-shaped body 202 having an open upper face 203, a bottom portion 204, and side wall portions 205 provided on all sides, and a plurality of treatment-object set portions 210 which are inclined with respect to the bottom portion 204 and which receive treatment objects.
The treatment-object set portions 210 are inclined with respect to the bottom portion 204 at an angle different from a vertical angle. The interval between the treatment-object set portions 210 may be arbitrarily set, for example, according to the size and usage of the treatment objects, and the treatment-object set portions 110 may be attached in various manners, for example, by fitting or by integral formation. Further, the treatment-object set portions 210 can be variously modified without departing from the object of the present invention, for example, the treatment-object set portions 210 may be formed of a material having high thermal conductivity, or a heater or the like may be set in the treatment-object set portions 210.
In the container 200 having such a structure, treatment objects are substantially uniformly leveled along the inclination of the treatment-object set portions 210 by being simply fed from the upper face 203. Hence, heat from the heater is efficiently transferred to the treatment objects.
The above-described configuration is provided. Next, operation and advantages will be described.
By being indirectly heated in an oxygen-free condition in the first to fourth heating chambers 21 to 24 hermetically closed by the shielding doors 5, organic materials are subjected to dry distillation to form carbonized products, and dry distillation gas containing oil is taken out through the exhaust pipes 3.
High-temperature dry distillation gas taken out of the first to fourth heating chambers 21 to 24 is cooled by the cooling devices 6, so that the oil in the dry distillation gas is liquefied and recovered.
Surplus gas taken out from the cooling devices 6 contains oil that is not liquefied thereat. This oil is liquefied by contact with the oil adsorbing liquid stored in the oil recovery devices 7, and the liquefied oil is entrapped in the oil adsorbing liquid and is recovered.
The surplus gas is sent to the safety devices 9 after oil is sufficiently removed therefrom by the oil recovery devices 7. This can inhibit the oil from being liquefied and floating on the water stored in the safety devices 9, and can prevent shortage of water to be supplied via the wastewater tank 45 to the combustion furnace burners 62, 63, and 53 of a water combine combustion type.
In contrast, the surplus gas taken out via the safety devices 9 is transferred to the second odor and smoke eliminating devices 61. Since oil contained in the surplus gas passing through the safety devices 9 is reduced, the oil contained in the surplus gas is prevented from being liquefied and dripping outside at the gas suction fans provided at the entrances of the second odor and smoke eliminating devices 61.
In this way, gas exhausted from the second preliminary chamber 12, the first to fourth heating chambers 21 to 24, and the first cooling chamber 31 and containing a lot of combustible components passes through the second exhaust passages 60, is introduced into the second odor and smoke eliminating devices 61, and is burnt in the second odor and smoke eliminating devices 61. Also, odor and smoke are eliminated from the gas in high-temperature atmospheres in the second odor and smoke eliminating devices 61, and the gas is exhausted out from the heat exhaust pipes 65 of the second odor and smoke eliminating devices 61.
The carbonizing apparatus of the embodiment includes a plurality of preliminary chambers (first and second preliminary chambers 11 and 12) where a treatment object is safely transferred to heating chambers for performing thermal decomposition, heating chambers (first to fourth heating chambers 21 to 24) where the treatment object is thermally decomposed by heating, a plurality of cooling chambers (first to third cooling chambers 31 to 33) where processes after thermal decomposition of the treatment object are performed, shielding doors 5 that close the preliminary chambers (first and second preliminary chambers 11 and 12), the heating chambers (first to fourth heating chambers 21 to 24), and the cooling chambers (first to third cooling chambers 31 to 33) which are arranged in series, a transport means that transports the treatment object while opening and closing the shielding doors 5, and exhaust pipes 3 through which gas exhausted from the preliminary chambers (first and second preliminary chambers 11 and 12), the heating chambers (first to fourth heating chambers 21 to 24) and the cooling chambers (first to third cooling chambers 31 to 33) are taken out. In the carbonizing apparatus, the treatment object is carbonized while being sequentially passed through the preliminary chambers, the heating chambers, and the cooling chambers. Since the preliminary chambers are kept unheated, the treatment object is not heated in the preliminary chambers during passage therethrough.
As a result, the fear that dry distillation gas will be generated from the treatment object in the preliminary chambers is completely eliminated. Therefore, generation of dry distillation gas caused by preheating the treatment object in the preliminary chambers, even if the generation is slightly supposed, is completely prevented. In this way, even when the preliminary chambers communicate with the outside of the apparatus, dry distillation gas will not leak out of the apparatus because it is not generated in the preliminary chambers. Therefore, the risk of explosion of dry distillation gas is completely eliminated, and a considerably high level of safety is secured.
It is needless to say that the present invention is not limited to the above-described embodiment and that various modifications are possible without departing from the object of the present invention.
According to the present invention, when a treatment object passes through the preliminary chambers, it is not heated through the passage of the preliminary chambers, because the preliminary chambers are kept unheated. As a result, the fear that dry distillation gas will be generated from the treatment object in the preliminary chambers is completely eliminated. Therefore, generation of dry distillation gas caused by preheating the treatment object in the preliminary chambers, even if the generation is slightly supposed, is completely prevented. In this way, even when the preliminary chambers communicate with the outside of the apparatus, dry distillation gas will not leak out of the apparatus because it is not generated in the preliminary chambers. Therefore, the risk of explosion of dry distillation gas is completely eliminated, and a considerably high level of safety is secured.
Further, according to the present invention, the treatment-object set portions in the container that receive the treatment object enhance thermal decomposition efficiency in heating treatment for carbonizing the organic material in the treatment object by thermal decomposition (dry distillation).
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-243873 | Oct 2009 | JP | national |
| 2010-233031 | Sep 2010 | JP | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2010/067604 | Sep 2010 | US |
| Child | 13435237 | US |
