JP2009121779A - Pressurized fluidized incineration equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressurized fluidized incineration equipment free from a risk of flowing-out of a lubricant from a turbine outlet side. <P>SOLUTION: This pressurized fluidized incineration equipment includes a pressurized fluidized furnace 10 for a treated object S, a supercharger 40 having a turbine 41 driven by an exhaust gas, and a compressor 42 driven by a driving shaft 46 of the turbine 41 and pressurizing the air supplied into the pressurized fluidized furnace 10, a lubricant circulation mechanism 90 having a partitioning material surrounding a shaft part including the driving shaft 46, a tank 91 storing the supplied lubricant, an upstream passage 92 for guiding the lubricant in the tank 91 into a sealed container, a liquid feed pump 93 for forcibly feeding the lubricant in the lubricant tank 91 into the partitioning material through the upstream passage 92, and a downstream passage 94 for guiding the lubricant in the partitioning material to the lubricant tank 91, and an inner pressure of the downstream passage 94 is lower than that of the upstream passage 92. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pressurized fluidized incineration facility. More specifically, the object to be treated is fluidized and combusted under pressure, the turbine is driven by the exhaust gas generated by the combustion, the compressor is driven by the rotational force of the drive shaft of the turbine, and the pressure is increased by driving the compressor. The present invention relates to a pressurized fluidized incineration facility configured to supply air into a pressurized fluidized furnace.

  At present, a pressurized fluidized bed combined power plant using coal as fuel is put into practical use. Normally, when a plant is started up, a turbocharger of a turbine is used as an electric motor to start up to a predetermined pressure and temperature. ing. However, in such a system that uses a supercharger as an electric motor, since the supercharger cannot be used as a starter blower, a large-capacity starter blower is often separately provided.

By the way, as a method of effectively using the exhaust of the turbine, the present applicant has disclosed Patent Document 1. However, Patent Document 1 does not disclose that the compressor is driven by the rotational force of the drive shaft of the turbine, the air is pressurized by driving the compressor, and the pressurized air is effectively used.
In this regard, as a method of driving the compressor by driving the turbine and using the air pressurized by the driving of the compressor, the present applicant supplies the pressurized air into the pressurized fluidized furnace. Disclosed. However, Patent Document 2 does not disclose how to supply (lubricate) the lubricating oil to the shaft portion including the turbine drive shaft.
In this regard, according to a normal idea of those skilled in the art, a partition material that surrounds the shaft portion including the drive shaft, a tank of lubricating oil supplied into the partition material, and the lubricating oil in the lubricating oil tank is used as the partition material. An upstream path leading into the interior, a liquid feed pump that forcibly sends the lubricating oil in the lubricating oil tank into the partition material through the upstream path, and a downstream that guides the lubricating oil supplied into the partition material to the lubricating oil tank A lubricating oil circulation mechanism with a route, etc. will be provided.
However, in a pressurized fluidized incineration facility that fluidizes and burns an object to be treated, the exhaust gas that drives the turbine is high pressure, the turbine inlet side is high pressure, and the air in the compressor is also high pressure. There is a possibility that the circulation of the lubricating oil sent by the liquid feed pump will be delayed. When the circulation of the lubricating oil is delayed, the pressure in the circulation mechanism increases, and the lubricating oil may flow out from the low pressure turbine outlet side. The spilled lubricating oil may be entrained in the exhaust gas and released into the atmosphere.

In addition, if the partition material surrounds the shaft portion so as to completely seal (air-tighten) and the partition material and the turbine inlet side and outlet side are completely shut off, the above problems occur. Absent. However, it is difficult to completely seal the partition material as long as it surrounds the drive shaft that is rotationally driven.
JP-A-9-89232 JP 2007-170705 A

  SUMMARY OF THE INVENTION The main problem to be solved by the present invention is to provide a pressurized fluidized incineration facility in which there is no risk of lubricant flowing out from the turbine outlet side.

The present invention that has solved this problem is as follows.
<Invention of Claim 1>
A pressurized fluidizing furnace for fluidizing and burning a workpiece under pressure;
A turbocharger having a turbine driven by exhaust gas generated by the combustion, and a compressor connected to a drive shaft of the turbine and driven by the rotational force of the drive shaft to pressurize the air supplied into the pressurized fluidized furnace. Machine,
A partition material surrounding the shaft portion including the drive shaft, a lubricating oil tank for storing lubricating oil supplied in the partition material, an upstream path for guiding the lubricating oil in the lubricating oil tank into the partition material, and this upstream path The lubricating oil having a liquid feed pump for forcibly sending the lubricating oil in the lubricating oil tank into the partition material through, and a downstream path for guiding the lubricating oil supplied in the partition material to the lubricating oil tank The circulation mechanism of
A pressurized fluidized incineration facility comprising:
The internal pressure of the downstream path is configured to be lower than the internal pressure of the upstream path.
A pressurized fluidized incineration facility characterized by that.

<Invention of Claim 2>
A pressurized fluidizing furnace for fluidizing and burning a workpiece under pressure;
A turbocharger having a turbine driven by exhaust gas generated by the combustion, and a compressor connected to a drive shaft of the turbine and driven by the rotational force of the drive shaft to pressurize the air supplied into the pressurized fluidized furnace. Machine,
A partition material surrounding the shaft portion including the drive shaft, a lubricating oil tank for storing lubricating oil supplied in the partition material, an upstream path for guiding the lubricating oil in the lubricating oil tank into the partition material, and this upstream path The lubricating oil having a liquid feed pump for forcibly sending the lubricating oil in the lubricating oil tank into the partition material through, and a downstream path for guiding the lubricating oil supplied in the partition material to the lubricating oil tank The circulation mechanism of
A pressurized fluidized incineration facility comprising:
A path that communicates the lubricating oil tank and the exhaust gas path downstream of the turbine is provided, and the internal pressure of the downstream path is configured to be lower than the internal pressure of the upstream path.
A pressurized fluidized incineration facility characterized by that.

<Invention of Claim 3>
The lubricating oil tank is arranged at a higher position than the partition material, and after the operation of the lubricating oil pump is stopped, the lubricating oil in the lubricating oil tank naturally flows into the partition material through the upstream path. The pressurized fluidized incineration equipment according to claim 1 or 2 constituted to.

Embodiments of the present invention will be described below.
As shown in FIG. 1, the pressurized fluidized incineration facility of the present embodiment includes a pressurized fluidized furnace 10 that combusts the workpiece S, a turbine 41 that is driven by the exhaust gas generated by the combustion, and the turbine 41. And a supercharger 40 that is connected to the drive shaft 46 and is driven by the rotational force of the drive shaft 46 and has a compressor 42 that pressurizes the air supplied into the pressurized flow furnace 10.

  The pressurized fluidized furnace 10 is supplied with workpieces S such as biomass, municipal waste, and dewatered cake of sewage sludge from the supply port, and at the time of startup, fuel and combustion for combustion from the lower starter burner 12 Service air is supplied. As will be described later, pressurized air is blown from the lower part of the pressurized fluidized furnace 10, and the object to be processed S is fluidized and burned by the fluidization energy.

  The exhaust gas generated by the combustion incineration is sent to the air preheater 20 through the flow path 71, and then passes through the dust collector 30 such as a bag filter or a ceramic filter through the flow path 72 and then through the flow path 73 of the supercharger 40. Guided to turbine 41.

  In the supercharger 40, the turbine 41 is driven by the exhaust gas, and the compressor 42 connected to the turbine 41 via the drive shaft 46 is also driven. After the exhaust gas expanded in the turbine 41 is guided to the white smoke prevention preheater 50 through the flow path 74, the exhaust gas is guided to the smoke treatment tower 60 through the flow path 75, and after being purified by the smoke treatment tower 60. It is emitted from the chimney 62 into the atmosphere.

  However, it is preferable that the exhaust gas expanded by the turbine 41 is led to a steam boiler (not shown), for example, before being led to the white smoke prevention preheater 50. The exhaust gas expanded by the turbine 41 has a high temperature and a high pressure of, for example, 400 to 450 ° C. and 0.02 to 0.05 MPa, and thus can recover heat and generate steam. Therefore, the steam generated by the steam boiler is guided to the exhaust gas treatment system upstream of the turbine 41, and the steam is mixed into the exhaust gas. As a result, the amount of exhaust gas guided to the turbine 41 increases, so the amount of air pressurized by the compressor 42 also increases, improving the thermal efficiency of the entire pressurized fluidized incineration facility.

  The exhaust gas treatment system upstream of the turbine 41 includes a flow path 73 that leads the exhaust gas from the dust collector 30 to the turbine 41, a flow path 71 that leads the exhaust gas from the pressurized fluidized furnace 10 to the air preheater 20, and exhaust gas from the air preheater 20 to the dust collector. The flow path 72 leading to 30, the pressurized fluidized furnace 10, the air preheater 20, the dust collector 30, and the like can be exemplified. The air preheater 20 is for preheating the pressurized air supplied into the pressurized fluidized furnace 10 by the heat of the exhaust gas.

By the way, in this embodiment, as shown in FIG. 1, a starter blower 43 is provided for the compressor 42. The air from the starter blower 43 is sent to the compressor 42 through the flow path 76 having the switching valve 44 and is pressurized by the compressor 42 to be pressurized air. This pressurized air is guided to the air preheater 20 through the flow path 77 and the flow path 78 and further supplied into the pressurized fluidized furnace 10 through the flow path 79. Further, a branch path 80 that leads to the starter burner 12 of the pressurized flow furnace 10 branches off from the flow path 77. The compressed air is supplied as combustion air to the starter burner 12 through the branch path 80 in addition to the pressurized fluidized furnace 10. Here, the advantage of providing the branch path 80 will be described.
That is, it is uneconomical to provide a dedicated blower for sending combustion air to the starter burner 12 only for start-up operation about once or twice (at most several times) per year. It will only lead to soaring. In particular, in order to send combustion air to the pressurized fluidized furnace 10 having a large capacity until the pressurized fluidized furnace 10 reaches a stable operation in a predetermined pressurized state, the dedicated blower must be enlarged. The pressure of the pressurized fluidized furnace 10 is a low pressure at the start-up, but needs to be increased with the passage of time. Therefore, it is necessary for the dedicated blower to have a capacity that can handle the low discharge pressure and low air flow rate at the start-up and the high discharge pressure and high air flow rate after the passage of time. . However, the pressurized fluidized incineration facility of the present embodiment is configured to supply air to the pressurized fluidized furnace 10 by supplying air from the starter blower 43 provided for the compressor 42 through the compressor 43 (channels 77 to 79). ), And a branch path (flow path 80) branched from this path and continuing to the start burner 12 of the pressurized fluidized furnace 10, and when the pressurized fluidized furnace 10 is started up, In addition to the pressurized fluidized furnace 10, the starting burner 12 is supplied as combustion air through a branch path. As a result, when the temperature rises due to the progress of combustion over time and the pressure in the pressurized fluidized furnace 10 increases, the compression ratio of the compressor 42 increases, and the pressure of the air pressurized by the compressor 42 is increased. The pressure is always higher than the pressure in the fluidized-furnace 10 (increased by the pressure exceeding the pressure loss in the fluidized part in the pressurized fluidized furnace 10). As the pressure in the pressurized fluidized furnace 10 increases, the air volume at the outlet side of the compressor 42 also increases. As a result, even with the startup blower 43 having a small capacity, it is possible to ensure a high discharge pressure and a high air flow rate after a lapse of time. Accordingly, a dedicated blower is not used to send the combustion air for the starter burner 12 hypothetically shown as reference numeral 43A in FIG. 1, or an extremely small one is sufficient, and the equipment cost and running cost are reduced. be able to. Further, since the pressure in the pressurized fluidized furnace 10 and the pressure of the pressurized air blown into the pressurized fluidized furnace 10 as combustion air are linked, it is easy to control the combustion air amount in the starter burner 12. There are also advantages.

  On the other hand, the white smoke prevention preheater 50 is, in the conventional form, white smoke prevention air mixed in the exhaust gas before being sent from the white smoke prevention fan hypothetically illustrated as reference numeral 52A and released into the atmosphere. Heat is recovered from the exhaust gas expanded by the turbine 41 and preheated. The preheated white smoke prevention air heats the clean air from the flue gas treatment tower 60 in the chimney 62 so that white smoke is not generated. The flue gas treatment tower 60 is intended to finally clean the exhaust gas before being released into the atmosphere through the white smoke prevention preheater 50, and employs a wet dust collection system or the like.

  Here, in the present embodiment, the white smoke prevention fan 52A is not provided, and the white air is prevented by branching from the flow path 77 for supplying the air pressurized by the compressor 42 into the pressurized flow furnace 10. A flow path 52 serving as a branch path that is connected to the preheater 50 is provided. Then, the pressurized air is guided to the white smoke prevention preheater 50 through the flow path 52 as white smoke prevention air. When the workpiece S has a high water content, for example, the exhaust gas from the high-pressure fluidized furnace 10 contains water vapor, so that the amount of air pressurized by driving the compressor 42 increases, and this pressurized air is added. A surplus occurs only by supplying the fluid into the pressure fluidized furnace 10. The start burner 12 is used as combustion air during start-up operation. However, in the above embodiment, the excess air is effectively used as white smoke prevention air. The use as the air for preventing white smoke is used in the pressurized flow incineration equipment system, and the white smoke prevention fan 52A is not used or can be made extremely small. Running cost can be reduced. Regarding the use of this surplus air, a pressure gauge 77A is provided in the flow path 77 through which the pressurized air passes, and the opening of the control valve 47 provided in the flow path 52 is adjusted by the pressure measured by the pressure gauge 77A. It is possible to adjust the ratio between the pressurized air led to the pressure fluidized furnace 10 and the pressurized air led to the white smoke prevention preheater 50.

  On the other hand, in this embodiment, a supply flow path 81 having a switching valve 45 that guides the external air A around the equipment to the compressor 42 is provided. During start-up operation, air is sent from the starter blower 43 to the compressor 42, and a predetermined temperature and pressure, for example, the inlet temperature of the turbine 41 is 350 ° C. or higher and the pressure is 0.11 to 0.15 MPa as an index. When the stable operation is reached, the switching valve 44 is closed, and instead, the switching valve 45 is opened and the external air A is sent to the compressor 42 through the supply flow path 81. Thereafter, this condition continues.

Conventionally, in a bubbling flow furnace that does not perform pressurization that is used for incineration, it is necessary to continuously operate a flow blower and to install an induction fan for forcibly exhausting from the chimney 62 In the pressurized fluidized incineration facility according to the present embodiment, it is only necessary to use the starter blower 43 at the time of start-up, so that there is an advantage that running cost is reduced and installation of an induction fan becomes unnecessary.
Although there is no limitation on the operating conditions of the pressurized fluidized furnace 10, it is desirable to pressurize to about 0.1 to 0.3 MPa and to set the temperature to about 800 to 850 ° C. from the viewpoint of preventing dioxin generation.

  By the way, in the pressurized flow incinerator of this embodiment, as shown in FIG. 2, a partition material (not shown) surrounding a shaft portion including a drive shaft 46 of the turbine 41 and a bearing (not shown) of the drive shaft 46, and the partition Lubricating oil tank 91 for storing lubricating oil supplied into the material, an upstream path 92 for guiding the lubricating oil in the lubricating oil tank 91 into the partition material, and a lubricating oil in the lubricating oil tank 91 through the upstream path 92 A lubricating oil circulation mechanism 90 having a liquid feed pump 93 that forcibly feeds the lubricating oil into the partition material and a downstream path 94 that guides the lubricating oil supplied into the partition material to the lubricating oil tank 91 is provided. As a result, the lubricating oil in the lubricating oil tank 91 repeats circulation through the upstream path 92, the partition material, and the downstream path 94 and back into the lubricating oil tank 91.

  Here, if only the above circulation mechanism 90 is provided, the inlet side of the turbine 41 becomes a high pressure as described above, so that the partition material also becomes a high pressure and is sent by the liquid feed pump 93. Lubrication oil circulation may be delayed. When the circulation of the lubricating oil is delayed, the pressure in the circulation mechanism 90 increases, and the lubricating oil may flow out from the outlet side of the turbine 41 that is at a low pressure.

However, in the pressurized fluidized incineration facility of this embodiment, a pressure adjusting path 95 that communicates the lubricating oil tank 91 and the flow path 74 that is an exhaust gas path downstream of the turbine 41 is provided. When this pressure adjustment path 95 is provided, the internal pressure of the exhaust oil path downstream of the turbine 41 such as the flow path 74 is low, so the internal pressure of the lubricating oil tank 91 is also reduced. As a result, the internal pressure of the downstream path 94 also decreases and becomes lower than the internal pressure of the upstream path 92. And when such a pressure difference arises, since the lubricating oil in a partition material will be in the state attracted | sucked in the downstream path 94, the stagnation in a partition material is prevented and the outflow from the turbine 41 exit side is prevented. Is done.
The (pressure) difference between the internal pressure of the downstream path 94 and the internal pressure of the upstream path 92 can be adjusted, for example, by providing a gate valve or the like in the pressure control path 95 and adjusting the opening of the gate valve. .

On the other hand, in the pressurized fluidized incineration facility provided with the lubricating oil circulation mechanism 90 as described above, the following problems are assumed.
That is, when the equipment is stopped urgently for some reason, the operation of the liquid feed pump 93 constituting the circulation mechanism 90 is also stopped, and as a result, the supply of the lubricating oil from the lubricating oil tank 91 to the partition material is also stopped. However, even if the equipment is urgently stopped, exhaust gas continues to be generated for a while, so that the turbine 41 is driven and the drive shaft 46 is driven to rotate. Therefore, if the liquid supply pump 93 stops simultaneously with the emergency stop of the equipment and the supply of the lubricating oil stops, the drive unit including the drive shaft 46 that continues to rotate may be broken.
Therefore, as shown in FIG. 3, the lubricating oil tank 91 is preferably arranged at a higher position than the partition material. According to this embodiment, even after the operation of the lubricating oil pump 93 is stopped, the lubricating oil in the lubricating oil tank 91 naturally flows down into the partition material through the upstream path 92, so that a failure of the driving unit including the driving shaft 46 occurs. Is prevented.

It is explanatory drawing of the structural example of a pressurization fluidization incineration equipment. It is explanatory drawing of the structural example of the circulation mechanism of lubricating oil. It is explanatory drawing of the modified structural example of the circulation mechanism of lubricating oil.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Pressurized flow furnace, 12 ... Start-up burner, 20 ... Air preheater, 30 ... Dust collector, 40 ... Supercharger, 41 ... Turbine, 42 ... Compressor, 43 ... Start blower, 50 ... Preheat for white smoke prevention , 60 ... Flue gas treatment tower, 90 ... Circulation mechanism, 91 ... Lubricating oil tank, 92 ... Upstream path, 93 ... Liquid feed pump, 94 ... Downstream path, 95 ... Pressure regulation path, S ... Processed object

Claims (3)

A pressurized fluidizing furnace for fluidizing and burning a workpiece under pressure;
A turbocharger having a turbine driven by exhaust gas generated by the combustion, and a compressor connected to a drive shaft of the turbine and driven by the rotational force of the drive shaft to pressurize the air supplied into the pressurized fluidized furnace. Machine,
A partition material surrounding the shaft portion including the drive shaft, a lubricating oil tank for storing lubricating oil supplied in the partition material, an upstream path for guiding the lubricating oil in the lubricating oil tank into the partition material, and this upstream path A liquid feed pump for forcibly sending the lubricating oil in the lubricating oil tank into the partition through the downstream, and a downstream path for guiding the lubricating oil supplied in the partition to the lubricating oil tank The circulation mechanism of
A pressurized fluidized incineration facility comprising:
The internal pressure of the downstream path is configured to be lower than the internal pressure of the upstream path.
A pressurized fluidized incineration facility characterized by that. A pressurized fluidizing furnace for fluidizing and burning a workpiece under pressure;
A turbocharger having a turbine driven by exhaust gas generated by the combustion, and a compressor connected to a drive shaft of the turbine and driven by the rotational force of the drive shaft to pressurize the air supplied into the pressurized fluidized furnace. Machine,
A partition material surrounding the shaft portion including the drive shaft, a lubricating oil tank for storing lubricating oil supplied in the partition material, an upstream path for guiding the lubricating oil in the lubricating oil tank into the partition material, and this upstream path The lubricating oil having a liquid feed pump for forcibly sending the lubricating oil in the lubricating oil tank into the partition material through, and a downstream path for guiding the lubricating oil supplied in the partition material to the lubricating oil tank The circulation mechanism of
A pressurized fluidized incineration facility comprising:
A path that communicates the lubricating oil tank and the exhaust gas path downstream of the turbine is provided, and the internal pressure of the downstream path is configured to be lower than the internal pressure of the upstream path.
A pressurized fluidized incineration facility characterized by that.   The lubricating oil tank is arranged at a higher position than the partition material, and after the operation of the lubricating oil pump is stopped, the lubricating oil in the lubricating oil tank naturally flows into the partition material through the upstream path. The pressurized fluidized incineration equipment according to claim 1 or 2 constituted to.

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