JP2003299929A - Method for regenerating filter cloth for dust-collector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for regenerating a filter cloth for a dust-collector realizing a use of the filter cloth for a long period of time by scattering an oil content deposited on the filter cloth of the dust-collector for treating gas discharged from a gasification furnace. <P>SOLUTION: In the filtration type dust-collector 1, the oil content attached and deposited on a surface of the filter cloth 4 and accumulated at the inside is decomposed and volatilized by raising a temperature of the filter cloth to a predetermined set temperature against a usual operation temperature. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of regenerating a filter cloth of a filtration type dust collector by scattering oil accumulated on the surface of the filter cloth or oil accumulated and entangled inside the filter cloth to regenerate the filter cloth,
Particularly, the present invention relates to a dust collector that treats exhaust gas containing a large amount of oil, such as a gasification furnace.

[0002]

2. Description of the Related Art The temperature of the dust collecting gas of a dust collector that processes gas discharged from a conventional gasification furnace or the like is the same as the temperature of the discharged gas or a cooling device provided at the dust collector inlet side. Using a filter cloth having a heat-resistant temperature that can be handled by the temperature control mechanism, the dust collector is designed by setting the filtration wind speed according to the temperature and setting the temperature so that it is below the heat-resistant temperature of the filter cloth.

[0003]

However, in the case of a dust collector for treating gas discharged from a gasification furnace or the like, the temperature of the dust collecting gas is usually up to about 400 ° C. Adhesion of oil and unburned materials causes the dust collection efficiency of the dust collector to drop significantly, and the oil content, etc., will adhere to the filter cloth more than the suction capacity of the induction blower installed on the discharge side of the dust collector, and when passing through the filter cloth. The life of the filter cloth is reached when the pressure loss increases.

At present, as a measure for preventing the oil content from adhering to the filter cloth, it has only been attempted to prevent the oil content and unburned matter from being produced by furnace combustion control.

In view of the above problems, the present invention provides a filter cloth for a dust collector which scatters oil content adhering to the filter cloth of a dust collector for treating gas discharged from a gasification furnace or the like and allows the filter cloth to be used for a long period of time. The purpose is to provide a reproducing method.

[0006]

In order to achieve the above object, a method of regenerating a filter cloth for a dust collector according to the present invention is a filter type dust collector in which a gas temperature flowing into the dust collector is set to a predetermined set temperature with respect to a normal operating temperature. It is characterized in that it decomposes and volatilizes the oil that adheres to the surface of the filter cloth, accumulates, and accumulates inside. Here, the "predetermined set temperature" means that the oil content that adheres to the surface of the filter cloth, accumulates, and is entangled and accumulated inside is decomposed.
It refers to the temperature at which it can be volatilized.

As a result, it is possible to postpone the replacement time of the filter cloth having the increased pressure loss, and to prolong the life of the filter cloth significantly.

In this case, the temperature of the inflowing gas can be raised by reducing the cooling degree of the gas flowing into the filtration type dust collector.

Thus, the temperature of the dust collecting gas can be easily increased by controlling the cooling device provided on the inlet side of the dust collector.

Further, the temperature of the inflowing gas can be raised by heating the gas flowing into the filtration type dust collector.

As a result, the gas temperature can be raised even in the dust collector that processes the gas having a low temperature at the dust collector inlet.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a method for recycling a filter cloth for a dust collector according to the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a filter-type dust collector 1 for treating a gas having a relatively high temperature. The gas sent to the dust-collector is always cooled by a cooling device 2 and then treated in the filter-type dust collector 1. FIG.

Gas and dust-containing air discharged from the gasification furnace or the like are sent to the dust-containing air chamber of the filter-type dust collector 1 through the inflow pipe 5 of the filter-type dust collector 1. At this time, when the gas to be sent exceeds the operating temperature to be processed in the predesigned dust collector, the cooling device 2 is operated to cool it to a specified temperature, and then the gas is sent to the inside of the filter dust collector 1.

The gas and dust-containing air sent to the dust-containing air chamber 7 of the filter-type dust collector 1 are filtered by the filter cloth 4 and sent to the purified air chamber 8 and discharged to the outside air through the discharge pipe 6. The gas flow from the inflow pipe 5 to the exhaust pipe 6 is performed by a suction fan F provided in the exhaust pipe 6.

When the filter cloth 4 is filtered, harmful substances such as dust contained in gas and dust-containing air are deposited on the surface of the filter cloth 4, and the dust collection efficiency (filtration efficiency) is reduced by a certain amount or more. In this case, the pressure air supply switching valve 11 is opened periodically, and the pressure air jet nozzle 10 is inserted through the backwashing pipe 9.
The compressed air is blown into the inside of the filter cloth 4 to scavenge the dust adhering to the surface of the filter cloth 4 and deposit it on the lower part of the filter type dust collector 1.

The dust accumulated in a certain amount is stored in a stocker (not shown) by opening and closing the rotary valve 13 and processed by using an air conveying means or the like.

Dust and the like other than the oil content is removed by backwashing by ejecting the above-mentioned pressurized air, and the dust collection efficiency is restored. However, the oil component (tar etc.) contained in the gas adheres to and accumulates on the surface of the filter cloth, or accumulates inside the filter cloth and becomes entangled.

These oils cannot be removed by backwashing by jetting pressurized air as described above,
Dust collection efficiency is significantly reduced. This has the effect of adhering non-combustible particles (alumina, silica, etc.) to oil, and if the amount of oil that adheres to and accumulates on the surface of the filter cloth increases, the dust, etc. other than oil will also adhere to the oil. It cannot be washed off by backwashing, which shortens the life of the filter cloth.

In the present invention, during normal operation, the cooling degree of the cooling device 2 is lowered, the temperature of the gas fed into the dust collector is increased, and the oil content deposited on the surface of the filter cloth 4 or the inside of the filter cloth is accumulated. Decomposes oil that accumulates and is entangled
The filter cloth 4 is scattered by being volatilized, and the filter cloth 4 is returned to a state in which oil is not attached and accumulated, thereby significantly improving the life of the filter cloth.

According to the experiments conducted by the present inventors, when the normal operation of the filter type dust collector 1 is 400 ° C., the cooling degree of the cooling device 2 is lowered and the temperature of the gas fed into the filter type dust collector 1 is 480 ° C. or more ( By setting the temperature to preferably 500 ° C. or higher), most of the oil that adheres to and deposits on the surface of the filter cloth or that accumulates inside the filter cloth and is entangled is decomposed and volatilized to be scattered.

FIG. 2 shows an embodiment of a filter type dust collector 1 for treating a gas having a relatively low temperature. The gas sent to the dust collector is always at the discharged temperature or after being heated by the heating device 3. FIG. 3 is an explanatory diagram of a case of processing in the filtration dust collector 1.

Also in this case, as in the case described above, the oil content adheres to the surface of the filter cloth in proportion to the operating time of the filter type dust collector 1.
Accumulates or accumulates inside the filter cloth and becomes entangled.

In the second embodiment of the present invention, during normal operation, the temperature of the gas fed into the dust collector is raised by heating by the heating device 3 (in the case of constant heating, the heating degree is increased). The oil that has adhered to and accumulated on the surface of the filter cloth 4 or the oil that has accumulated and entangled inside the filter cloth is decomposed and volatilized to be scattered, and the filter cloth 4 is returned to the state in which the oil has not been adhered and accumulated. Greatly improve the life of.

At this time, the cooling device 2 and the heating device 3 may be used in combination depending on the kind and temperature of the gas to be treated.

FIG. 3 is an explanatory view of an operation intended only for regenerating the filter cloth, not during the normal operation for treating the gas or dust-containing air discharged from the gasification furnace or the like.

Reference numeral 14 denotes a circulation duct which connects the rear side of the discharge pipe 6 and the front side of the inflow pipe 5, and normally, valves V3 and V4.
Is closed and the valves V1 and V2 are opened, and the gas and dust-containing air discharged from the gasification furnace or the like are treated by the method described above.

When the oil content adhering to and accumulated on the surface of the filter cloth 4 or the oil content accumulated and entangled inside the filter cloth increases by the operation for a certain period of time, the normal operation of the dust collector is stopped.

Thereafter, the valves V1 and V2 are closed and the valves V3 and V4 are opened. As a result, the filter dust collector 1 becomes a closed circuit in which the rear of the discharge pipe 6 and the front of the inflow pipe 5 are connected, and only the air of the filter dust collector 1 is circulated by the circulation fan F ′.

At this time, the heating device 3'is operated to raise the temperature of the circulating air, thereby adhering to the surface of the filter cloth 4,
The accumulated oil and the oil entangled and entangled inside the filter cloth are decomposed and volatilized to be scattered, and the filter cloth 4 is returned to a state in which the oil is not adhered and accumulated, thereby significantly improving the life of the filter cloth. .

The temperature of the air to be circulated can be set to 480 ° C. or higher (preferably 500 ° C. or higher) to scatter the oil content, as in the case described above.

The upper limit of the temperature to be raised is the heat resistant temperature of the filter cloth used. As a material for general filter cloth, ceramic, alumina-silicate fiber molded type filter cloth or cordierite, and sintered type filter cloth have a heat resistant temperature of 850 ° C., woven type using ceramic fiber or stainless fiber The heat resistant temperature of the woven cloth and ceramic coating type is 500 ° C.

Although the method for recycling the filter cloth for the dust collector of the present invention has been described above based on the embodiments thereof, the present invention is not limited to the configurations described in the above embodiments and does not deviate from the spirit thereof. The configuration can be appropriately changed within the range.

[0034]

As described above, according to the present invention, the dust collector having a reduced dust collection efficiency due to the oil components attached to and deposited on the surface of the filter fabric or the oil components accumulated and entangled inside the filter fabric (the collection efficiency is reduced). The filter cloth can be regenerated by a simple method of raising the temperature of the gas flowing into the dust collector from the normal processing temperature by about 80 to 120 ° C., and the life of the filter cloth can be greatly improved.

When the treatment temperature is raised by reducing the cooling degree of the cooling device, it can be used in almost all existing dust collectors.

Further, when the treatment temperature is raised by using a heating device, even in a dust collector for treating a gas having a relatively low temperature, the oil content attached to and deposited on the surface of the filter cloth can be scattered to regenerate the filter cloth. And so on.

[Brief description of drawings]

FIG. 1 is an explanatory view of an embodiment of a method for recycling a filter cloth for a dust collector of the present invention.

FIG. 2 is an explanatory view of another embodiment of the method for recycling the filter cloth for the dust collector of the present invention.

FIG. 3 is an explanatory view of another embodiment of the method for recycling the filter cloth for the dust collector of the present invention.

[Explanation of symbols]

1 Filter dust collector 2 Cooling device 3 heating devices 4 filter cloth

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takamasa Kijima             4-30 Shioe, Amagasaki-shi, Hyogo Japan Su             Inside Pindle Manufacturing Co., Ltd. F-term (reference) 4D058 JA02 JA04 MA41 SA15 SA20

Claims (3)

[Claims] 1. In a filter type dust collector, the gas temperature flowing into the dust collector is raised to a predetermined set temperature with respect to the normal operating temperature, and the oil content adhering to the surface of the filter cloth, accumulated, and decomposed and volatilized is volatilized. A method for recycling a filter cloth for a dust collector, which is characterized. 2. A method of regenerating a filter cloth for a dust collector according to claim 1, wherein the temperature of the inflowing gas is raised by reducing the cooling degree of the gas flowing into the filtration dust collector. 3. The method for recycling a filter cloth for a dust collector according to claim 1, wherein the temperature of the inflowing gas is raised by heating the gas flowing into the filter type dust collector.