JPS601044B2 - Dust collection method using bug filter - Google Patents

Description

[Detailed Description of the Invention] This invention is designed to suck and conduct dust gas from a dust generation source such as a coke oven, an electric furnace, a blast furnace bank, a steel factory, etc., where the amount of dust generated varies depending on the content of the work, to a bag filter. The present invention relates to a dust collection method in which dust collection is performed using a dust collection method.

Conventionally, in the dust collection method using this type of bag filter,
The dust gas from the dust source is controlled by the suction air volume control mechanism according to the amount of dust generated, while controlling the suction air volume of the exhaust blower.
The suction is conducted to the dust collection section divided into multiple parts of the bag filter, and the dust collected in the bag is collected by a large number of bugs in the bag filter. Each time, a damper opening/closing switching mechanism is operated to shake the bugs off, and a special suction blower generates a backwash airflow, which causes the bugs to contract and expand, and is then brushed off and removed.

In other words, the suction air volume is controlled according to the amount of dust generated, reducing wasted power consumption of the exhaust blower and saving energy.In addition, bugs are removed from each dust collection section using a timer. By performing over-collection of dust gas in the other dust collection sections that are not being brushed off, it is possible to continuously collect dust for a long period of time without stopping the dust gas from the dust source. In addition, when the damper opening/closing switching mechanism operated by the above-mentioned timer control is electrically interlocked with the suction air volume control mechanism and controlled to obtain the maximum suction air volume as the amount of dust gas generated from the dust generation source increases, Even when the time for dust removal by the timer comes, the dust removal mechanism is not operated, and the dust gas from the dust source is conducted to all the dust collection sections to collect the dust, thereby reducing or stopping the amount of dust gas generated by the dust source. Accordingly, by operating the dust removal mechanism only when the suction air volume control mechanism is controlling the air volume, even if the furnace does not have an excessive capacity, the furnace overflow speed increases and the furnace dust collection efficiency decreases. The system is designed to be able to operate without causing problems, thereby reducing the size of the entire device and reducing equipment costs and operating costs.

By the way, in the above-mentioned conventional method, an exhaust blower that suctions and conducts dust gas to each dust collection section and exhausts it, and a suction blower that generates a backwash airflow to blow off the dust collected from bugs are separately provided and operated. There is.

Therefore, two expensive blowers were required, which was uneconomical, and the operation of both blowers had to be controlled individually, which was troublesome. Therefore, recently, instead of using a suction blower dedicated to generating backwash airflow for dust removal, only a main exhaust blower is installed to suck and guide the dust gas from the dust source to the dust collection section of the bag filter. A method has been considered in which the suction action of a blower performs both the collection of dust gas and the action of removing dust from each dust collection section. The schematic configuration of a bag filter device that is equipped with only this main exhaust blower and performs dust collection processing and dust removal is described with reference to Fig. 1.The bag filter 1 is divided into a plurality of parts. A dust collection section 2..., a large number of bugs 3 suspended in each dust collection section 2, and a dust removal hopper 4 disposed at the bottom of each dust collection section 2. ...and a suction port 5 protruding from each hopper 4
. . . and a dust gas communication duct 6 connected to each suction port 5, an exhaust port 7 with an opening/closing damper 7a provided at the upper end of each dust collection section 2, and a backwash airflow with an opening/closing damper 8a. An exhaust duct 9 connected to the inlet 8 and each of the exhaust ports 7, a set of exhaust blowers 10 disposed at the terminals of the exhaust duct 9, and an outside air intake duct connected to each of the backwash airflow inlets 8. It consists of 11. Then, by the suction action of the exhaust blower 10, dust gas from a dust source (not shown) is sucked and conducted into each hopper 4 through each suction port 5 through a dust gas introduction duct 6, and from there to each dust collection section. The clean air passing through the bag 3 inside the bag 3 is collected, and the clean air that escapes to the outside of the bag 3 is discharged from the upper exhaust port 7 through the exhaust duct 9 to the atmosphere from the exhaust blower 10.

Also, during the dust collection operation, a damper opening/closing mechanism (not shown) is installed in each dust collection section 2 using a damper.
is operated to repeatedly open and close the opening/closing dampers 7a and 8a, thereby closing the opening/closing damper 7a and opening the opening/closing damper 8a, thereby conducting dust gas from other dust collecting sections 2 into the dust collecting section 2 concerned. Duct 6, suction port 5
By applying the suction action of the exhaust blower 10 through the
Outside air is sucked into the dust collection section 2 from above as a backwash airflow, and a backwash airflow of the outside air and a normal dust gas flow are alternately generated inside the dust collection section 2. By repeating the contraction and expansion of the bags 3, the dust collected on the bags 3 is brushed off and settled in the lower hopper 4 for removal. However, in the above-mentioned method of collecting dust gas and removing dust only by the suction operation of the main exhaust blower 10, in order to reduce wasteful power consumption, as in the past, the amount of dust gas generated from the dust source is If the suction air volume of the exhaust blower 10 is controlled by a suction air volume control mechanism (not shown), the suction air volume of the exhaust blower 10 will be at its minimum when the dust source is at rest or when the amount of dust generated is small. If the time and the timing of dusting off by the timer match, even if the opening/closing dampers 7a and 8a of the dust collection section 2 are switched open and closed, the suction pressure is low, so the required backwash airflow is not generated in the dust collection section 2. Therefore, the dust gas cannot be removed effectively, and the dust gas is introduced after the dust removal period has elapsed without the bug 3... being regenerated. There was a problem in which the pressure drop resistance of the filter increased abnormally, causing a major problem in dust collection.

The present invention has been made in view of the above circumstances, and provides an exhaust blower in which dust gas from a dust source is controlled by a suction air volume control mechanism according to the amount of dust generated.

At the same time, suction is conducted to each dust collection section by a blower to collect the dust in the furnace, and a timer is used to operate a damper opening/closing mechanism for each dust collection section to generate a backwash airflow by suction from the exhaust blower to remove dust. In the method for removing dust, the damper opening/closing switching mechanism is electrically interlocked with the suction air volume control mechanism to control the maximum suction air volume when the amount of dust generated by the dust source increases, and when the amount of dust generated is reduced. During the low suction air volume control, the dust gas is continued to be conducted to each dust collecting section without operating the damper opening/closing switching mechanism even when the time for dust removal by the timer comes, and the dust is removed until the intermediate suction air volume control state is reached. It is characterized by delaying the dropping time, and this prevents an increase in the furnace overflow speed at maximum suction airflow, which in turn prevents the furnace overflow dust collection efficiency from decreasing, and also prevents the generation of backwash airflow from insufficient pressure during low suction airflow control. The object of the present invention is to provide a method that avoids scandals such as inability to remove dust and allows continuous and effective dust collection operation at all times. An embodiment of the method of the present invention will be described below.

Here, a method of collecting dust gas generated from a coke oven (not shown) which is a source of dust generation using the bag filter 1 shown in FIG. 1 will be exemplified. First, in the above-mentioned coke oven, dust is normally collected using a suction air volume that corresponds to the various dust sources that change during the operation of the oven, as shown in FIG. That is, when the furnace lid is removed during coke cake extrusion, dust gas is generated from the furnace mouth. At this time, the exhaust blower 10 is controlled to an intermediate suction air volume to collect dust at the kiln mouth. Since a large amount of dust gas is generated near the guide car during coke cake extrusion work performed during this furnace mouth dust collection, the guide car dust is collected by controlling the exhaust blower 10 to the maximum suction air volume. In addition, dust gas is generated from the coal charging port during the coal charging operation after coke cake extrusion is completed.
The exhaust blower 10 is controlled to an intermediate suction air volume to collect dust from the coal loading car. Furthermore, since almost no dust gas is generated when each furnace working equipment such as a guide car is moved to the next furnace or is at rest, the exhaust blower 10 is controlled to the maximum suction air volume of 4.0 and the furnace is at rest. The suction air volume control mechanism that controls the suction air volume automatically controls the exhaust blower by means of a fluid coupling, a thyristor motor, a Serbus motor, a marine clutch, etc. in response to the operation of the furnace working equipment such as the guide car. 10
It is controlled by controlling the rotation speed of the exhaust blower, or by controlling the opening and closing of the vanes built into the exhaust blower. Therefore, the dust gas generated from the coke oven,
The suction air volume corresponding to the amount of dust gas generated during the various furnace operations is conducted to each dust collection section 2 of the bag filter 1 to over-collect the furnace. The opening/closing switching mechanism is operated to remove dust from each dust collecting section 2 one after another.

At this time, the damper opening/closing switching mechanism is electrically interlocked with the suction air volume control mechanism, and the dust blowing timing by the timer is controlled to an intermediate suction air volume by the exhaust blower 10 during dust collection of the coal loading car, etc., as shown in FIG. Only when the state is the same as the state in which The bug 3... is generated repeatedly and the dust from it is brushed off to regenerate the bug 3..., and the maximum suction air volume state during other guide car dust collection is controlled, when it is stopped, and the minimum suction air volume state. When the time for dust removal by the above-mentioned timer comes during the control, the damper opening/closing switching mechanism is not operated and normal dust collection operation is continued without operating, and the exhaust blower 10 is controlled to the above-mentioned intermediate suction air volume. When this state is reached, the damper opening/closing switching mechanism is operated to remove dust in the same manner as above. In addition,
Although the above embodiment describes a method for collecting dust from a coke oven, the present invention is not limited to this, and can also be applied to collecting dust gas from various dust sources such as electric furnaces.

Since the method of this invention is performed as described in detail above, the dust gas is passed through the furnace by suction only by the main exhaust blower whose suction air volume is controlled according to the amount of dust generated by the dust source, and the dust gas is collected through the furnace. The system uses a timer to set the timing of dust removal, and also electrically interlocks the suction air volume control mechanism to set the time when the suction air volume is at maximum and when it is below a certain level. Since the dust removal operation is not performed when the suction air volume is low, the increase in the furnace overflow speed at the maximum suction air volume is reduced.
In addition to preventing excessive dust collection efficiency from decreasing in the furnace, it is also possible to avoid problems such as inability to remove dust due to insufficient backwash air flow generation pressure at low suction air volumes, resulting in always effective dust collection operation. This means that you can continue to do so.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a bag filter device used in the method of the present invention, and Fig. 2 is a diagram showing an embodiment of the method of the present invention. FIG. 3 is an explanatory diagram illustrating the suction air volume state in a time flow chart at the time of the operation, and FIG. 3 is an explanatory diagram illustrating the bag internal pressure in the same embodiment in a time flow chart. 1... Bag filter, 2... Dust collection section, 3
...bug, 10...exhaust blower, 7a, 8a...opening/closing dan/f
-oFigure 1Figure 2Figure 3

Claims (1)

[Claims] 1 Dust gas from a dust generation source is sucked and conducted into each dust collection section divided into multiple parts of the bag filter by a suction air volume control mechanism according to the amount of dust generated, and is filtered and captured by a large number of dust collection sections in the dust collection section. At the same time, the purified air is discharged to the outside via the exhaust blower, and the dust collected in the bugs is removed by the exhaust blower by operating the damper opening/closing mechanism for each dust collection section using a timer. At the same time, the suction airflow control mechanism is electrically interlocked with the damper opening/closing switching mechanism, and the exhaust blower is turned to maximum suction as the amount of dust from the dust source increases. When the air volume is controlled to a low level, or when the amount of dust generated decreases and the exhaust blower is controlled to a low suction air volume that is less than the backwash air flow generation pressure due to this suction, even when the time for dust removal by the above timer comes. This dust collection method using a bag filter is characterized in that dust gas is continued to be conducted to each dust collection section without operating a damper opening/closing switching mechanism, and the timing of dust removal is delayed until the dust collection air volume is controlled to an intermediate suction air volume.