KR930001526B1 - Exhaust gas processing device - Google Patents

Abstract

No content.

Description

Exhaust gas treatment system

1 is a system diagram of an exhaust gas treating apparatus according to a preferred embodiment of the present invention.

2 is a cross-sectional view of the spray cooling tower, the adsorbent supply device, and the dust collector bug chamber in the system of FIG.

3 is a plan view of the spray cooling tower, the adsorbent supplying device, and the dust collector bug chamber of FIG.

4 is a system diagram of a conventional exhaust gas treating apparatus.

* Explanation of symbols for main parts of the drawings

2: electric furnace 4: combustion tower

6: preheating device 7: gas cooler

10: dust sedimentation tower 12: seal collector blower

14: stamp collector dust chamber 16, 18: spray cooling tower

20: adsorbent supply device 22: duct

24: adsorbent receiving

The present invention relates to an exhaust gas treating apparatus of a scrap preheater used for an electric furnace.

The system of the conventional waste gas processing apparatus is shown in FIG. In the electric furnace 2, a combustion tower 4 for burning noxious gas, preheating devices 6, 6 and a gas cooler 8, dust for preheating scraps disposed in parallel with each other. A sedimentation tower 10, a straight dust collector blower 12, and a straight dust collector bug chamber 14 are sequentially provided in series.

The exhaust gas temperatures in this route are 1300 ° C, 800 ° C, 250 ° C, 300 ° C and 250 ° C at the points ⓐ, ⓑ, ⓒ, ⓓ and ⓔ in Fig. 4, respectively. However, the conventional technique shown in FIG. 4 has the following problems.

(A) Exhaust gas having a temperature of 250 ° C. is sent to the dust collector bug chamber 14, and there is a fear that a fire may be caused by the combustion of dust, oil mist, and organic solvent in the exhaust gas in the bug chamber 14. .

(B) Since exhaust gas is high temperature, the condensation degree of oil mist, organic solvent, etc. in the bug chamber 14 is poor, and these removal efficiency is low.

(C) Therefore, the exhaust gas emitted from the bug chamber 14 into the atmosphere contains a considerable amount of white lead, odor, and harmful components, which is not preferable in terms of environmental pollution. In order to solve the above problems, there is also a method of installing a flush flush tower downstream of the articulated dust collector bug room or a liquefied oil-flush absorption tower downstream of the articulated dust collector bug room. The debris removal rate is not good, and the processing is downstream from the bug room, so the fire protection of the bug room is not effective.

In order to solve the above problem, there is also a method of adding a porous adsorbent to the upstream line of the dust collector blower to physically adsorb and remove dust, although it is effective to remove white smoke. It is almost ineffective for removal, and the exhaust gas temperature cannot be lowered, and therefore, it is not effective for fire protection of the dust collector bug chamber.

An object of the present invention is to provide an exhaust gas treatment apparatus that has excellent performance in all of oil mist removal, odor component removal, organic solvent removal, white smoke removal, and the like, and also serves as a fire countermeasure for the dust collector bug chamber. According to the present invention, the above object is achieved by the following exhaust gas treating apparatus. That is, the electric furnace is connected in series with a combustion tower, a preheater and a gas cooler, a dust settling tower, and a linear dust collector blower which are parallel to each other, and at least one stage downstream of the electrical linear dust collector blower. Can be achieved by an exhaust gas treatment device in which a direct flush spray cooling tower equipped with a fan), an adsorbent supply device for supplying a porous adsorbent, and a dust collector bug chamber are connected in series in this order.

In the conventional example, a spray cooling tower and an adsorbent provided with at least one stage between a linear dust collector blower and a linear dust collector bug chamber in the present invention device, while the linear dust collector bug chamber is directly connected to and connected to the linear dust collector blower. The apparatus of the present invention differs from the conventional apparatus in that the supply apparatuses are provided in series in sequence. With respect to the action, by installing the spray cooling tower upstream of the linear dust collector bug chamber and downstream of the linear dust collector blower, the temperature of the gas entering the linear dust collector bug chamber is lowered to about 80 ° C., thereby eliminating the risk of bug fire. . Since the temperature of the exhaust gas is lowered by spray cooling or the like, the oil mist and the organic solvent are condensed. The oil mist and the organic solvent are added to the condensed oil component and the organic solvent component by adding the adsorbent made of porous material in the adsorbent supply device. Solvent, white smoke, and odor removal efficiency is significantly higher.

Since the cooling tower sprays spray water directly onto the exhaust gas, dust and foreign matter in the exhaust gas can be directly washed and dropped. In addition, direct blowing is effective for reducing the temperature of the exhaust gas. These spray cooling towers and adsorbent supply devices can be added to the exhaust gas treatment system of the existing arc furnace scrap preheater without additional design changes and arrangements. It can also be used to improve exhaust emissions.

EXAMPLE

A preferred embodiment of the exhaust gas treating apparatus according to the present invention will be described below with reference to the drawings of FIGS. 1 to 3.

1 shows the system of the apparatus.

The same components as those of the conventional apparatus shown in FIG. 4 are denoted by the same reference numerals as those of FIG. 4 for clarity of correspondence between the present invention and the conventional apparatus.

In FIG. 1, the electric furnace 2 includes a combustion tower 4 for burning noxious gas, preheating devices 6, 6 and a gas cooler 8 (preheating) for preheating scraps which are provided along a path. The apparatus 6 and the gas cooler 8 are provided in series in the order), the dust settling tower 10, and the linear dust collector blower 12 in series.

The scrap preheated in the preheaters 6 and 6 is then dissolved in an electric furnace 2. The temperatures of the gas at points ⓐ, ⓑ, ⓒ, ⓓ and ⓔ in FIG. 1 are 1300 ° C, 800 ° C, 250 ° C, 300 ° C and 250 ° C, respectively, as in the prior art. A straight dust collector bug chamber 14 is provided downstream of the straight dust collector blower 12, and the arrangement relationship with the straight dust collector bug chamber 14 of the straight dust collector blower 12 may face each other as in the prior art.

That is, when applying this invention as an improvement of the existing waste gas processing apparatus, the relative arrangement relationship of the linear dust collector blower 12 and the linear dust collector bug chamber 14 becomes the same as before.

However, in the present invention, between the dust collector blower 12 and the dust collector bug chamber 14, (a) is installed in at least one stage, that is, in the embodiment, a direct flush spray cooling tower installed in two stages. (16), (18), and (b) The adsorbent supply device 20 is provided in this order. That is, the spray cooling towers 16 and 18 are arrange | positioned upstream rather than the adsorption agent supply apparatus 20. FIG.

As shown in FIGS. 2 and 3, the spray cooling towers 16 and 18 are disposed on the tops of the towers 16a and 18a and the towers 16a and 18a which are hollow inside. At least one sprayed water jet pipe 16b, 18b is retained.

Then, the exhaust gas is introduced into the tower 16a from the top of the tower 16a of the first stage and the sprayed water is blown directly into the exhaust gas, and then the exhaust gas is discharged from the lower vicinity of the tower 16a of the first stage, and 2 It enters into the tower 18a from the upper part of the tower | column 18a of the stage, and is discharged | emitted from the lower vicinity of the tower 18a. Water sprayed from the towers 16a and 18a, dust and foreign substances washed with the water, oil mist and organic solvent absorbed by the water are collected in the lower portions of the towers 16a and 18a. It discharges as needed through the drain 16c, 18c provided in the lower part of the tower 16a, 18a.

The spray water ejection pipes 16b and 18b eject the water droplets toward the entire cross-sectional area in the column so that the exhaust gas and the spray water directly contact each other. The adsorbent supply device 20 is a device for supplying a porous particulate adsorbent by dropping it from the upper portion of the duct 22 into the duct 22 connecting the spray cooling tower 18 and the dust collector bug chamber 14. The adsorbent receiver 24 is provided in the lower part which falls down.

The adsorbent 26 is supplied to be in direct contact with the exhaust gas flowing in the duct 22. The adsorbent 26 is composed of a porous material containing diatomaceous earth activated carbon as a main component. For example, an adsorbent sold under the trade name zeolite can be used.

One example of such an adsorbent is 47.5% SiO ₂ , 2.3% Al ₂ O ₃ , 2.2% Fe ₂ O ₃ , 24.9% CaO.

Such adsorbents have a very large surface area because of the porous surface of the particles, and condensate to form water droplets that adsorb and absorb oil components and organic solvent components floating in the exhaust gas to remove odors, white smoke, and harmful components. It has a big effect on having. FIG. 3 shows the spray cooling towers 16 and 18 and the adsorbent supply device by providing a duct between the linear dust collector blower 12 and the linear dust collector bug chamber 14 of the existing actual device. 20) is provided in the dust collector bug chamber 14, indicating that it can be compactly and easily disposed.

It should be noted here that the relative positional relationship between the linear dust collector blower 12 and the linear dust collector bug chamber 14 is sufficient as previously installed, and the spray cooling towers 16, 18 and the adsorbent supply device 20 are By the additional installation, the relative position of the dust collector bug chamber and the dust collector blower of the conventional apparatus need not be changed. Therefore, the present invention can be easily added to an existing device as an improvement on environmental pollution of the conventional device.

Next, the operation of the above-described embodiment of the present invention will be described. The exhaust gas flows from the electric furnace 2 to the linear dust collector blower 12 and is sent out to the downstream by the linear dust collector blower 12 as in the prior art. The exhaust gas enters the spray cooling tower 16 through the duct, and when the spray cooling tower is installed in multiple stages, the exhaust gas flows in series and is discharged from the spray cooling tower 18 at the final stage. (22) enters the dust collector bug room (14), where it is discharged into the atmosphere. In the duct 22 between the spray cooling tower 18 and the dust collector bug chamber 14 at the final stage, the adsorbent 26 is directly supplied to the exhaust gas from the adsorbent supply device 20.

When the exhaust gas passes through the spray cooling towers 16 and 18, the exhaust gas is directly in contact with the spray water, and the temperature of the exhaust gas is drastically lowered, so that the spray cooling towers 16 and 18 of the first and second stages are reduced. It becomes 120 degreeC at ⓕ between and, and it goes down to 80 degreeC from the point of the inlet ⓖ of the linear dust collector bug room 14.

By cooling the exhaust gas in the spray cooling towers 16 and 18 as described above, the oil mist and organic solvent in the exhaust gas condense into droplets, and some of them are sprayed with dust and foreign matter. It is washed with water and collected in the lower portions of the spray cooling towers 16 and 18 and discharged from the drains 16c and 18c. Droplet oil components and organic solvent components not removed from the spray cooling towers 16 and 18 flow into the adsorbent supply device 20 together with the flow of the exhaust gas, where they are dropped from the adsorbent supply device 20 and supplied. It adsorb | sucks to many particle | grains type | mold adsorbents 26, and is discharged | emitted from the adsorbent receiver 24.

In this way, the low-temperature exhaust gas from which the oil component and the organic solvent component are removed with high accuracy is sent to the dust collector bug chamber 14.

The effect by the present invention is as follows.

(A) Since the spray cooling towers 16 and 18 were installed upstream of the linear dust collector bug chamber 14, when the exhaust gas reached the linear dust collector bug chamber 14, the exhaust gas temperature was sufficiently high, for example, 80 ° C. There is no fear of a fire occurring in the dust collector bug chamber 14 after descending to the extent.

(B) Spray cooling towers 16 and 18 are installed to lower the exhaust gas temperature, and spray cooling towers 20 and 18 are provided with adsorbent supply devices 20 downstream of the spray cooling towers 16 and 18. It is possible to effectively adsorb and remove the oil and the organic solvent condensed and dripping in (16) and (18) by the adsorbent 26 in the adsorbent supply device 20.

(C) A table is prepared by comparing the above-described effects with the conventional methods of flush absorption, liquefied emulsion absorption, and special filter adsorption.

As apparent from Table 1, according to the present invention, it is excellent in any of oil removal, odor removal, organic solvent removal, white smoke removal, topical measures, etc., and is very good as a comprehensive evaluation.

Table 1 Arrangement and Evaluation of Test Results

Claims (3)

In the electric furnace 2, a combustion tower 4, preheating devices 6, 6, and a gas cooler 7, a dust settling tower 10, and a dust collector blower 12, which are parallel to each other, are provided. In order to be connected in series and downstream of the aforementioned linear dust collector blower 12, a direct flush spray cooling tower and a linear dust collector bug chamber 14 having at least one stage are connected in series in this order. An exhaust gas treatment device characterized in that an adsorbent supply device (20) for supplying a porous adsorbent into the duct is provided in a duct (22) connecting the spray cooling tower and the electrical dust collector bug chamber that is electrically connected to the spray cooling tower. The exhaust gas treatment apparatus according to claim 1, wherein the spray cooling towers (16) and (18) of the aforementioned direct flush type are provided in two stages in series. 2. The exhaust gas according to claim 1, wherein the porous adsorbent supplied from the adsorbent supply device 20 described above is composed of an adsorbent composed mainly of 47.5% SiO ₂ , 2.3% Al ₂ O ₃ , 2.2% Fe ₂ O ₃ , and 24.9% CaO. Gas treatment device.

Images