JP3679833B2 - Dust removal system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dust removal system, and particularly has a relative high temperature exhaust gas source and low temperature exhaust gas source, and is useful when applied to the regeneration of a filter using the exhaust gas in addition to the dust removal of the exhaust gas.
[0002]
[Prior art]
Dust is contained in the exhaust gas discharged from the boiler device and the waste incinerator. Therefore, in order to prevent air pollution, the boiler device or the like is provided with a dust removing device for removing (collecting) dust.
[0003]
The following are known as conventional dust removing devices used for boiler devices and the like.
[0004]
(1) Centrifugal dust collector In this centrifugal dust collector, centrifugal force is used to give a large acceleration (swivel speed) to the exhaust gas to separate the dust from the gas. A type dust collector is known.
In addition, in centrifugal dust collectors represented by cyclone type dust collectors, dust is removed using centrifugal force, so dust particles are collected unless the particle diameter of dust particles contained in the gas is larger than a certain level. I can't.
[0005]
(2) Filtration type dust collector A filtration type dust collector collects soot and dust by filtering exhaust gas with a filter cloth using Teflon fiber or glass fiber, and is known as a bag filter. In this filtration type dust collector, the dust collecting chamber is divided into a plurality of parts, and the dust collected is sequentially removed for each chamber. There are a mechanical vibration method, a reverse pressure removal method, a pulse jet method, and the like.
In the bug filter, it is necessary to make the gas flow rate passing through the bug very slow, and so many bugs are required.
[0006]
(3) Electric dust collector In the electrostatic dust collector, the corona discharge around the discharge electrode is used to charge the dust particles in the gas, and the Coulomb force is applied to the charged particles to attract the dust particles to the dust collection electrode. Collect.
In addition, in an electrostatic precipitator, if particle diameters, such as a dust, are not larger than a certain amount, a dust cannot be collected and big electric power is consumed.
[0007]
By the way, on remote islands, power is generated by diesel power generation facilities. In this diesel power generation facility, a generator is rotated by a diesel engine.
The exhaust gas from the diesel engine naturally contains soot, but at present, the diesel power generation equipment is not equipped with a dust removing device in most cases. The reason is as follows.
[0008]
The particle size of soot and dust contained in exhaust gas from diesel engines is extremely small (see Fig. 8), whereas centrifugal dust collectors, filtration dust collectors and electric dust collectors have particles of about 1 [μm] or more. The dust cannot be collected unless the dust is of a diameter, and even if these conventional dust collectors are provided, the dust removal efficiency is extremely poor.
[0009]
Even if the dust removal efficiency is poor, even if the conventional dust collector is installed to reduce the amount of dust emission, even if the conventional dust collector is installed, a large flow (passage) resistance is added to the exhaust gas, and the pressure loss increases and the efficiency of the diesel engine increases. There is a demerit that it is reduced (especially when a bag filter is used) or a large amount of generated power is consumed for dust removal (especially in the case of an electric dust collector).
[0010]
Accordingly, the inventors of the present application have developed a dust removing device that can collect dust with a small particle diameter and that has low pressure loss and low power consumption (Japanese Patent Application No. 2-1473: hereinafter referred to as “prior application”). Called).
[0011]
Here, an outline of the dust removing device of the prior application will be described with reference to FIG. As shown in the figure, the casing 01 is partitioned by a partition plate 02 to form five flow paths 03. Each flow path 03 is provided with a damper 06, a heater 07, and a filter 08 in order from the inlet side (inlet gas duct 04 side) to the outlet side (outlet gas duct 05 side).
[0012]
The damper 06 is rotated by a motor (not shown) to open and close the flow path 03. The heater 07 generates heat by generating a current and regenerates the filter 08. That is, the filter 08 is heated, and the dust collected by the filter 08 (fuel soot, oil mist generated by scattering of lubricating oil, etc.) is combusted. The filter 08 is formed of a ceramic porous body.
[0013]
The exhaust gas is sent from the inlet gas duct 04 into the casing 01. In order to collect the dust in the exhaust gas, the damper 06 is opened without passing an electric current through the heater 07. As a result, the exhaust gas passes through the filter 08 and dust is collected in the filter 08. The exhaust gas that has passed through the filter 08 is sent to the chimney via the outlet gas duct 05.
[0014]
The regeneration of the filter 08 is periodically performed by shifting the phase in order for each flow path 03. This reproduction method will be described with reference to FIG. In addition, in order to distinguish each flow path 03 here, code | symbol 03-1, 03-2, 03-3, 03-4, 03-5 is attached | subjected and demonstrated.
[0015]
As shown in FIG. 10, in the period T ₁ , regeneration is performed in the flow path 03-1 and dust is collected in the flow paths 03-2, 03-3, 03-4, and 03-5. That is, in the flow path 03-1, the damper 06 is closed and a current is supplied to the heater 07 to heat the filter 08 to regenerate the filter, and the other flow paths 03-2, 03-3, 03-4, 03- 5, dust is collected by the filter 08 without opening the damper 06 and passing a current through the heater 07.
[0016]
In period T ₂ , regeneration is performed in the flow path 03-2, dust collection is performed in the other flow path, and in period T ₃ , regeneration is performed in the flow path 0-3 and soot collection is performed in the other flow path. Similarly, it collects in another flow path, reproducing | regenerating in one flow path.
[0017]
On the other hand, the diesel engine generally has a supercharger, and the dust removing device is connected to the downstream side of the supercharger.
[0018]
FIG. 11 is a block diagram showing the dust removal system in this case. In the figure, I has five independent chambers partitioned by a partition plate 02 by a dust removing device, and a heater 07 and a filter 08 are disposed in each chamber. In addition, exhaust gas flows into each chamber through an inlet damper 06 and exhaust gas flows out through an outlet damper 09. 010 is a diesel engine, 011 is a supercharger, and 012 is an exhaust pipe.
[0019]
[Problems to be solved by the invention]
In the dust removal system described above, the exhaust gas at the time of regeneration of the dust remover I is at the outlet side of the supercharger 011 even though the exhaust gas at the inlet side of the supercharger 011 generally equipped in the diesel engine 010 is high temperature and high pressure. Low temperature and low pressure are used. For this reason, there remains room for improvement in order to improve the reproduction efficiency.
[0020]
That is, there is no doubt that it is advantageous to use the exhaust gas on the inlet side of the high-temperature, high-pressure supercharger 011 when the filter 08 is regenerated. Incidentally, the exhaust gas on the inlet side of the supercharger 011 is 50 ° to 150 ° C. higher than the outlet side, and the heat-up temperature of the exhaust gas by the heater 07 can be reduced accordingly.
[0021]
In view of the above-described prior art, the present invention can efficiently regenerate the filter of the dust removing device when there are two types of exhaust gas sources of relatively high temperature and low temperature, such as the inlet side and the outlet side of the turbocharger. It aims at providing the dust removal system which can be performed.
[0022]
[Means for Solving the Problems]
The configuration of the present invention that achieves the above object is characterized by the following points.
[0023]
1) an exhaust gas source that emits relatively high temperature exhaust gas and low temperature exhaust gas;
A casing having a plurality of chambers through which exhaust gas flows from the inlet side to the outlet side, and installed by corresponding to each chamber. A plurality of dampers that prevent the exhaust gas from flowing through the chambers, heaters that are arranged in each chamber and generate heat when energized, and in each chamber at a position downstream of the heater along the exhaust gas flow direction. A dust removing device having a filter composed of a ceramic porous body disposed;
An exhaust pipe for guiding the low temperature exhaust gas for dust removal discharged from the exhaust gas source to the dust remover;
Other exhaust pipes that have branch pipes that communicate directly with the upstream side of the filter in each chamber of the dust remover and that guide the high temperature exhaust gas for regeneration of the filter discharged from the exhaust gas source to the dust remover via each branch pipe,
A hot gas valve disposed in each branch pipe to control the inflow of hot exhaust gas into each chamber of the dust remover,
The high temperature gas valve corresponding to at least one of the chambers is opened, the heater is energized and the damper is closed to regenerate the filter of the chamber, and the high temperature gas valves corresponding to the remaining chambers are closed, While the heater is de-energized and the damper is open, the exhaust gas is removed by the filter in the chamber, and the operation of the high-temperature gas valve, heater and damper is controlled so that the regeneration mode or dust removal mode is sequentially switched in each chamber. Configured to do.
2) In 1) above,
The exhaust gas source is composed of an internal combustion engine having a supercharger, while high temperature exhaust gas is supplied from the inlet side of the supercharger and low temperature exhaust gas is supplied from the outlet side of the supercharger.
3) In 1) above,
The exhaust gas source was a boiler.
4) a boiler which is an exhaust gas source that discharges high-temperature exhaust gas that can regenerate the filter of the dust removal device with the heat of the exhaust gas itself and low-temperature exhaust gas for dust removal;
A casing having a plurality of chambers through which exhaust gas flows from the inlet side to the outlet side, and installed by corresponding to each chamber. A dust removing device having a plurality of dampers for preventing exhaust gas from flowing through the chambers, and a filter made of a ceramic porous body disposed in each chamber;
An exhaust pipe for guiding the low temperature exhaust gas for dust removal discharged from the boiler to the dust removal device;
Other exhaust pipes that have branch pipes that communicate directly with the upstream side of the filter in each chamber of the dust remover and that guide the high-temperature exhaust gas for regeneration of the filter discharged from the boiler to the dust remover via each branch pipe,
A hot gas valve disposed in each branch pipe to control the inflow of hot exhaust gas into each chamber of the dust remover,
The high temperature gas valve corresponding to at least one of the chambers is opened and the damper is closed to regenerate the filter of the chamber, and the high temperature gas valves corresponding to the remaining chambers are closed and the damper is opened. The exhaust gas is removed by the filter in the chamber, and the operation of the high-temperature gas valve and the damper is controlled so that the regeneration mode or the dust removal mode is sequentially switched in each chamber .
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the same parts as those in FIG. 11 are denoted by the same reference numerals and redundant description is omitted.
[0028]
As shown in FIG. 1, in this embodiment, a separate exhaust pipe 101 is connected to the inlet side of the supercharger 011 and the exhaust pipe 101 is connected to each chamber 3a, 3b, 3c, 3d, 3e of the dust removing device II. Branch pipes 101a, 101b, 101c, 101d, and 101e communicating with the upstream side of the filter 5 are provided. Hot gas valves 102a, 102b, 102c, 102d, and 102e are interposed in the branch pipes 101a to 101e.
[0029]
The dust remover II includes a heater 4, a filter 5, inlet dampers 8a, 8b, 8c, 8d, and 8e, outlet dampers 11a, 11b, 11c, 11d, and 11e, etc., but exhaust gas flows from the lower part to the upper part. It is formed in a vertical shape to be discharged. Incidentally, the dust removing apparatus I shown in FIG. 11 is a horizontal type.
[0030]
In this embodiment, exhaust gas on the inlet side of the supercharger 011 is introduced into the regeneration mode chambers 3 a to 3 e for regenerating the filter 5 through the exhaust pipe 101. For example, when the chamber 3a is set to the regeneration mode, the hot gas valve 102a is opened and the entry damper 8a is closed.
[0031]
On the other hand, for the other chambers 3b to 3e, the high-pressure gas valves 102b to 102e corresponding to the chambers 3b to 3e are closed, and the inlet side dampers 8b to 8e are opened.
[0032]
Thus, high-temperature and high-pressure exhaust gas at the inlet side of the supercharger 011 is introduced into the chamber 3 a upstream of the filter 5, and the exhaust gas is reheated by the heater 4 to regenerate the filter 5. On the other hand, the exhaust gas on the outlet side of the supercharger 011 is introduced into the other chambers 3b to 3e to perform dust removal. After the regeneration relating to the chamber 3a is completed, the chambers in the regeneration mode are sequentially switched, for example, the chamber 3b. As a result, the regeneration of the filter 5 in each of the chambers 3a to 3e can be efficiently performed using high temperature and high pressure exhaust gas.
[0033]
As described above, in this embodiment, the exhaust gas of the diesel engine 010 is divided into the one for regeneration and the one for dust removal, but the distribution ratio of both is as follows: (1) Select the pipe diameter of the exhaust pipes 012 and 101, (2) High temperature The gas valves 102a to 102e can be easily selected by taking measures such as having a throttling function. Specifically, the exhaust gas for regeneration is a few percent of the exhaust gas for dust removal.
[0034]
In the above embodiment, the diesel engine 010 and the supercharger 011 are used as high-temperature and low-temperature exhaust gas sources, but other internal combustion engines may be used as long as they have a supercharger.
[0035]
Further, as shown in FIG. 2, the boiler 201 may be the high-temperature and low-temperature exhaust gas source. That is, in this case, in addition to the conventional exhaust pipe 202 through which the low-temperature exhaust gas flows, an exhaust pipe 203 through which the regeneration high-temperature exhaust gas flows can be provided and connected to the dust removing device II as in the embodiment shown in FIG. .
[0036]
When a boiler is used as an exhaust gas source, exhaust gas having a high temperature that can regenerate the filter 5 with the heat of the exhaust gas itself without being heated by the heater 4 may be obtained. Therefore, in this case, the heater 4 can be removed. Incidentally, when the exhaust gas source is an internal combustion engine, it is necessary to heat up to obtain a predetermined temperature for regeneration (about 600 ° C.).
[0037]
【Example】
Here, an embodiment useful as a dust removing device in the dust removing system as described above, particularly useful as a dust removing device of the diesel engine 010 will be described.
[0038]
FIG. 3 is a perspective view showing the dust removing device obtained in the present embodiment in a partially broken view. In this dust removing apparatus, four partition plates 2 are provided in the casing 1 in the vertical direction, and five chambers 3 a to 3 e are formed in the casing 1. Each of the chambers 3a to 3e extends in the vertical direction, and includes a heater 4 (described later in detail) and a filter 5 (described later in detail).
[0039]
Inlet gas ducts 6a to 6e communicate with the lower front sides of the respective chambers 3a to 3e. In each of the inlet gas ducts 6a to 6e, inlet side dampers 8a to 8e are opened and closed by driving of motors 7a to 7e. Is provided.
[0040]
In addition, outlet gas ducts 9a to 9e communicate with the rear sides of the upper portions of the respective chambers 3a to 3e, and outlet dampers 11a to 11e that are opened and closed by driving motors 10a to 10e in the outlet gas ducts 9a to 9e. (In the figure, 11b to 11e are not visible).
[0041]
The exhaust gas emitted from the diesel engine or the like is guided to the chambers 3a to 3e via the inlet gas ducts 6a to 6e, passes through the chambers 3a to 3e upward from below, and then passes through the outlet gas ducts 9a to 9e. Are discharged and sent to the chimney.
[0042]
On the other hand, each chamber 3a-3e is connected to branch pipes 101a-101e communicating directly with each chamber 3a-3e without passing through the inlet gas ducts 6a-6e, and each branch pipe 101a-101e is a high-temperature gas valve 102a. To 102e through the exhaust pipe 101. Thus, the high temperature exhaust gas for regeneration is configured to directly flow into the respective chambers 3a to 3e via the exhaust pipe 101 and the high temperature gas valves 102a to 102e.
[0043]
As shown in FIG. 4, the filter 5 has a structure in which two filter members 5-1 and 5-2 are arranged in a palm, that is, the upper side is connected and the gap between the two gradually increases toward the lower side. It has an open structure. And each filter member 5-1 and 5-2 are the structures which incorporated the ceramic porous body 5b in the frame material 5a. This ceramic porous body 5b is a mixture of cordierite (2MgO · Al ₂ O ₃ · 5SiO ₂ ) and alumina (Al ₂ O ₃ ), has 10 to 15 holes per inch, and has a porosity of (The porosity is 80 to 90%). The thickness of the ceramic porous body 5b (the length in the direction in which the exhaust gas passes) is 40 to 60 [mm].
[0044]
The flow rate of the exhaust gas (exhaust gas emitted from the diesel engine) flowing through the chambers 3a to 3e is as fast as 0.5 to 2 [m / sec], but the ceramic porous body 5b has a three-dimensional skeleton structure and its porosity Because of the large pressure loss. Moreover, although the diameter of the pores of the ceramic porous body 5b is as large as several [mm], the thickness of the ceramic porous body 5b is 40 to 60 [mm] and there are a plurality of continuous passages through the pores. can do. In the end, the porosity and thickness of the ceramic porous body 5b were determined so that both characteristics would be good in consideration of the pressure loss and the collection efficiency, which are related to the deterioration of the other.
[0045]
In addition, if it adds here, the flow velocity of the waste gas in a bag filter is as extremely slow as about 1-2 [m / min].
[0046]
Further, as shown in FIG. 5, the angle θ formed by the filter members 5-1 and 5-2 was set to 10 to 30 °. By doing in this way, the total area of the filter 5 becomes wide with respect to the cross-sectional area of a chamber, and it contributes to reduction of pressure loss.
[0047]
Further, as shown in FIG. 5, the heater 4 is arranged in a triangle at a position below the filter 5. When an electric current is passed through the heater 4, the heater 4 is heated, and the radiant heat of the heater strikes the ceramic porous body 5b, and the heated air rises and penetrates into the ceramic porous body 5b. Thereby, the ceramic porous body 5b can be heated and regenerated.
[0048]
As shown in FIG. 6, six heaters 4 may be arranged below the filter 5. A three-phase alternating current is supplied to the heater 4 having a triangular arrangement (FIG. 5) or a six-element arrangement (FIG. 6).
[0049]
The configuration of the heater 4 is as shown in FIG. That is, the heating element 4b is accommodated in the outer cylinder 4a, and this heating element 4b is supported in a state of penetrating the plurality of disks 4c. Further, a spacer 4d is provided between the disks 4c, and the open end (the left end in the figure) of the outer cylinder 4a is sealed with a refractory heat resistant material 4e. The heating element 4b generates heat by supplying power to the heating element 4b via the lead wire 4f.
[0050]
The base end (left end in FIG. 7) of this heater 4 is bolted to the front wall 1a of the casing 1, and the front end (right end in FIG. 7) is locked to the rear wall 1b of the casing 1.
[0051]
【The invention's effect】
As specifically described with the above embodiment, according to the present invention, the high-temperature exhaust gas and the low-temperature exhaust gas possessed by the exhaust gas source are used, and the exhaust gas for regeneration of the filter is used at a high temperature. Therefore, the rate of heat-up by the conventional heater can be reduced, and in some cases, there is no need for heat-up, so that the regeneration efficiency can be improved.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an embodiment of the present invention.
FIG. 2 is a block diagram showing another embodiment of the present invention.
FIG. 3 is a partially cutaway perspective view showing the dust removing apparatus according to the embodiment of the present invention.
FIG. 4 is a perspective view showing a filter.
FIG. 5 is a front view showing a filter and a heater.
FIG. 6 is a front view showing a filter and a heater.
FIG. 7 is a cross-sectional view showing a heater.
FIG. 8 is a characteristic diagram showing the dust diameter and its ratio in diesel exhaust gas.
FIG. 9 is a perspective view showing a conventional dust removing device with a part broken away.
FIG. 10 is a time sequence diagram showing a method of operating a conventional dust removing device.
FIG. 11 is a block diagram showing a conventional dust removal system.
[Explanation of symbols]
II Dust remover 1 Casing 2 Partition plates 3a to 3e Chamber 4 Heater 5 Filter 5-1 and 5-2 Filter member 5a Frame member 5b Ceramic porous bodies 6a to 6e Inlet gas ducts 7a to 7e Motors 8a to 8e Inlet dampers 9a to 9e Outlet gas ducts 10a to 10e Motors 11a to 11e Outlet damper 010 Diesel engine 011 Supercharger 012 and 101 Exhaust pipes 101a to 101e Branch pipes 102a to 102e Hot gas valve

Claims (4)

An exhaust gas source that emits relatively hot and cold exhaust gases;
A casing having a plurality of chambers through which exhaust gas flows from the inlet side to the outlet side, and installed by corresponding to each chamber. A plurality of dampers that prevent the exhaust gas from flowing through the chambers, heaters that are arranged in each chamber and generate heat when energized, and in each chamber at a position downstream of the heater along the exhaust gas flow direction. A dust removing device having a filter composed of a ceramic porous body disposed;
An exhaust pipe for guiding the low temperature exhaust gas for dust removal discharged from the exhaust gas source to the dust remover;
Other exhaust pipes that have branch pipes that communicate directly with the upstream side of the filter in each chamber of the dust remover and that guide the high temperature exhaust gas for regeneration of the filter discharged from the exhaust gas source to the dust remover via each branch pipe,
A hot gas valve disposed in each branch pipe to control the inflow of hot exhaust gas into each chamber of the dust remover,
The high temperature gas valve corresponding to at least one of the chambers is opened, the heater is energized and the damper is closed to regenerate the filter of the chamber, and the high temperature gas valves corresponding to the remaining chambers are closed, While the heater is de-energized and the damper is open, the exhaust gas is removed by the filter in the chamber, and the operation of the high-temperature gas valve, heater and damper is controlled so that the regeneration mode or dust removal mode is sequentially switched in each chamber. A dust removal system characterized by being configured to do so .   The exhaust gas source is constituted by an internal combustion engine having a supercharger, while the high temperature exhaust gas is supplied from the inlet side of the supercharger and the low temperature exhaust gas is supplied from the outlet side of the supercharger. The dust removal system according to claim 1.   The dust removal system according to claim 1, wherein the exhaust gas source is a boiler. A boiler that is a source of exhaust gas that discharges high-temperature exhaust gas that can regenerate the filter of the dust removal device with the heat of the exhaust gas itself and low-temperature exhaust gas for dust removal;
A casing having a plurality of chambers through which exhaust gas flows from the inlet side to the outlet side, and installed by corresponding to each chamber. A dust removing device having a plurality of dampers for preventing exhaust gas from flowing through the chambers, and a filter made of a ceramic porous body disposed in each chamber;
An exhaust pipe for guiding the low temperature exhaust gas for dust removal discharged from the boiler to the dust removal device;
Other exhaust pipes that have branch pipes that communicate directly with the upstream side of the filter in each chamber of the dust remover and that guide the high-temperature exhaust gas for regeneration of the filter discharged from the boiler to the dust remover via each branch pipe,
A hot gas valve disposed in each branch pipe to control the inflow of hot exhaust gas into each chamber of the dust remover,
The high temperature gas valve corresponding to at least one of the chambers is opened and the damper is closed to regenerate the filter of the chamber, and the high temperature gas valves corresponding to the remaining chambers are closed and the damper is opened. A dust removal system configured to control the operation of the high-temperature gas valve and the damper so that the regeneration mode or the dust removal mode is sequentially switched in each chamber while the dust in the exhaust gas is removed by a filter in the chamber .

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