JPS60216824A - Dust collecting method of combustion exhaust gas - Google Patents

Abstract

PURPOSE:To increase dust removing effects of fine granules and to lower the cost in a dust removing method by extracting one part of the titled exhaust gas, electrifying the soot and dust contained therein with an electrification apparatus and mixing the extracted exhaust gas with the exhaust gas introduced in a cyclone. CONSTITUTION:One part of gas (about 5-15% of combustion gas) is extracted through an extraction pipe C1 from a suitable place under a cyclone 1 and introduced into an electrification apparatus 2. After the soot and dust contained the extracted gas is electrified with the electrification apparatus, the gas is sent into an exhaust gas introducing pipe (a) through a mixing pipe (d) and mixed with the combustion gas and fed into the cyclone 1. By this method, the fine soot and dust contained in the combustion exhaust gas are adsorbed by the electrified soot and dust, flocculated to make bulky, separated and collected and the purified gas is discharged through a gas discharging pipe (b).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for efficiently collecting soot and dust contained in combustion exhaust gas, particularly soot and dust of fine particles.

As dust collectors for combustion exhaust gas, in addition to the water washing method, mechanical separation methods such as cyclones or electrical methods that charge the soot and dust in the exhaust gas and attract and coagulate the particles are used. Disposal of a huge amount of water after cleaning is a problem, and while mechanical methods are effective against relatively large soot particles, they are less effective against fine particles, which are released along with the gas.

Furthermore, the electrical method not only requires a huge amount of equipment but also has the drawback that the electricity consumed by the charging device during operation is expensive.

The present invention provides a new method that takes advantage of the characteristics of mechanical or electrical dust collection described above and eliminates the drawbacks, and examples thereof will be described below with reference to the accompanying drawings.

Figure 1 illustrates the basic method of this invention, in which 1 is a Zyclone for mechanically separating and collecting soot and dust, 2 is a charging device, 3 is a blower for blowing air, and a is a cyclone for cleaning combustion exhaust gas. b is a gas discharge pipe of cyclone 1; C is an extraction pipe that extracts a part of the combustion exhaust gas mixed with soot and dust from the lower part of cyclone 1 and supplies it to charging device 2; This is a mixing tube that sends the gas that has passed through the charging device 2 into the exhaust gas introduction pipe a, and the combustion exhaust gas is introduced into the cyclone 1 from the introduction pipe a, where the soot and dust in the exhaust gas is separated and settled downward. The collected exhaust gas and separated soot and dust are released from the upper gas release pipe.

A part of the gas, for example, about 5% to 15% of the combustion exhaust gas, is extracted from an appropriate position below the cyclone 1 through the extraction pipe C1 and introduced into the charging device 2. This extracted gas is mixed with the soot dust contained in the combustion exhaust gas, and after this soot dust is charged with a charging device 2, it is fed into the exhaust gas introduction pipe a through the mixing pipe d, mixed with the combustion exhaust gas, and then passed through the cyclone. Send it to 1.

By mixing the charged soot dust with the combustion exhaust gas as described above, the fine soot dust in the combustion exhaust gas is adsorbed and aggregated by the charged soot dust, becomes coarse, is separated and collected, and is added to the gas released from the gas discharge pipe. Only gas without microscopic particles that cannot be collected by a cyclone is released. Moreover, the gas and dust supplied to the charging device 2 are extracted from a part of the combustion exhaust gas, and are small compared to the total amount of exhaust gas, so the charging device 2 can be small and have a small capacity, and the power consumption required for charging. It is also inexpensive, requires simple equipment, and can provide excellent dust collection effects. The amount of gas extracted from the cyclone 1 and sent to the charging device 2 is adjusted by a blower 3 provided in the mixing tube d or a damper (not shown).

Fig. 2 shows another embodiment. In the embodiment shown in Fig. 1, a part of the soot and dust is extracted from below the cyclone 1 along with a small amount of gas. A part of the exhaust gas is extracted by the extraction pipe C2 and sent to the charging device.In this case, the soot and dust content in the extracted gas is lower than in the case shown in Fig. 1, but the extracted gas m
By adjusting , the same result as in the case of FIG. 1 can be obtained.

Figure 3 shows a part of the exhaust gas released from the gas discharge pipe b' of the cyclo mower into the extraction pipe 0. In this example, the dust contained in the extracted gas is only the dust that could not be collected by cyclone 1, and the dust content is lower than that in Figures 1 and 2, but the dust collection function for fine particles is still effective. will improve.

FIG. 4 shows one of the most preferred embodiments of the present invention, in which the combustion exhaust gas is fed into the first cyclone 4 from the exhaust gas introduction pipe a, and part or all of the soot and dust separated and collected in the same cyclone is transferred to the second cyclone 5. together with a small amount of exhaust gas,
The soot dust separated and collected by this second cyclone is discharged from below, and the gas is sent from above to the zone N device 2 through the extraction pipe C4, and further passes through the mixing pipe d, where it is mixed with the exhaust gas in the exhaust gas introduction pipe a. .

For example, the first and second cyclones 4 and 5 have a soot and dust separation ability of 2μ or more, and the first cyclone 4
The gas extracted together with the soot and dust accounts for 5% to 15% of the combustion exhaust gas.
%, the gas to be treated in the second cyclone is small compared to the amount of combustion gas, so a small-capacity cyclone is sufficient, and the soot and dust is separated and collected by the two → Neuclones, so good dust collection results can be obtained, and fine dust collection can be achieved. The release of particles can also be prevented.

Further, in the above embodiment, the first cyclone 4 and the second cyclone 5 have particle size collection performance, for example, the first cyclone 4 has a particle size collection performance of 2μ or more, and the second cyclone 5 has a particle size collection performance of 10μ or more. If the particles have a collection performance, the particles sent from the second cyclone 5 to the charging device 2 will be less than 10μ and have a uniform particle size, so that the charging state by the charging device 2 and the mixing state with the combustion exhaust gas will be improved. , the effect of collecting fine dust by the first cyclone 4 can be improved.

[Brief Description of the Drawings] Fig. 1 is an explanatory diagram illustrating the basic method of this invention, Figs. 2 and 3 are explanatory diagrams of other embodiments, and Fig. 4 is an explanatory diagram of a preferred embodiment of this invention. FIG. 1...Cyclone 2...Charging device 4...First cyclone 5...Second cyclone a...Combustion exhaust gas introduction pipe b...Gas discharge pipe C, C3, C4
...Extraction tube d...Mixing tube Patent applicant: Gumi Nishioka Representative: Patent attorney: Kazu 1) Akira

Claims (3)

[Claims] (1) Combustion characterized by extracting part of the soot dust in the combustion exhaust gas together with a small amount of the exhaust gas, charging the soot dust in the extracted exhaust gas with a charging device, and mixing it into the combustion exhaust gas introduced into the cyclone. How to collect dust from exhaust gas. (2) Separate and collect the soot dust in the combustion exhaust gas. The soot dust separated by the first cyclone is introduced into the second cyclone together with a small amount of gas, and the exhaust gas from the cyclone is introduced into the charging device,
A method for collecting dust from combustion exhaust gas according to claim 1, characterized in that the soot dust remaining in the exhaust gas is charged and mixed into the combustion exhaust gas introduced into the first Zykron. (3) The first cyclone and the second cyclone have different dust particle size collection performance.
Dust collection method for combustion exhaust gas as described in section.