JPS58133846A - Treatment of waste gas - Google Patents

Abstract

PURPOSE:To improve dust collecting efficiency as well as to prevent white smoking from a chimney and to improve a diffusion effect in the stage of treating waste gas with a wet type desulfurizer through an electrical dust precipitator by conducting the waste gas from the desulfurizer into the hollow dust precipitating electrodes in the dust precipitator. CONSTITUTION:For example, the waste gas of a coal boiler is cooled with an air heater 1 and is introduced into an electrical dust precipitator 2 consist of hollow dust precipitating electrodes 3 of pipe or square shape. However, in this state, the dust of high resistant sticks on the electrodes 3, and causes back corona phenomena, by which dust precipitating efficiency is decreased. Thereupon, the waste gas passes through the precipitator 2 and since the waste gas flowing out from a wet type desulfurizer 4 is low in temp., the waste gas is conducted to the electrodes 3 to cool the electrodes 3, whereby the temp. of the high resistance dust stuck thereon is reduced and the electric resistance value is decreased. Thus, back corona phenomena are prevented and dust precipitating efficiency is improved. On the other hand, the waste gas past the electrodes 3 is heated, whereby the white smoking of the gas released from a chimney 5 is prevented and a diffusion efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating exhaust gas from a coal boiler, for example, by using an electric waste treatment device and exhaust gas treatment equipment such as a wet desulfurization device installed after it. In case, F i1
Tatami boiler economizer → air heater → electric '911 shutsu haiga - comic style descaling, lung purchase - ◆The chimney and exhaust gas pass through. At this time, the temperature of the exhaust gas flowing out from the air heater and flowing into the electrostatic precipitator is between 150 and 150 degrees Celsius, and the temperature of the gas flowing out from the wet desulfurization device is 45 to 60°C. For this reason, the exhaust gas discharged from the chimney produces white smoke, has a poor diffusion effect, and the temperature of the exhaust gas flowing into the electrostatic precipitator is high (σ) in this state, the electrical resistance is large, and the pack corona is high. This phenomenon occurred, leading to a decrease in the dust collection rate.As a means to prevent this, the dust collection electrode of the electrostatic precipitator was installed as a hollow pipe or square plate with water etc. The heating medium VJAt.

A method is generally known in which the dust collection rate W is improved by lowering the temperature of the dust collecting electrode and lowering the electrical resistance of the collected dust.

The present invention is directed to exhaust gas flowing out from an active immersion type desulfurization device in a hollow collector pole of an electrostatic precipitator! It cools the dust collecting electrode, lowers the electrical resistance value of the dust adhering to the dust collecting electrode, prevents the pack corona phenomenon, and improves the service efficiency. The purpose is to prevent white smoke from forming and increase the diffusion effect - Pv. J, f, One embodiment of the present invention〉Described with reference to drawing Y (
1 in the figure is an air heater, which is a heat exchanger used to heat the furnace air. 2 is an electrostatic precipitator that removes dust from the exhaust gas and purifies it. The dust collection electrode of this W 2 is a hollow pipe or □ rectangular shape. This wet desulfurization device (4), which will be described later, has a structure that allows exhaust gas to pass through.4 is a 7-butt type desulfurization device, which removes the sulfur content in the exhaust gas.
L11 stones. Reference numeral 5 denotes a chimney from which the exhaust gas flowing out from the wet desulfurization equipment is released and diffused into the atmosphere.

In the I11 construction of the 4th floor, the exhaust gas of the r1 coal boiler was
7): J1v exits and enters the Qw air device 2 at a temperature of 130°C to 150″C.If this continues, high-resistance dust will accumulate on the dust collecting electrode 3 of the air collecting device 2. This causes a phenomenon of crystallization, and the dust collection rate increases. Then, the electrostatic precipitator 2V passes through, and the humidity f:, the main sulfur unit 4V passes, and the dust collection rate increases.
- The temperature of the exhaust gas is as low as 6or from 45℃, and the exhaust gas is guided to the hollow dust collection electrode 3 and collected at
5 V, the temperature of the high-resistance dust that adheres to the dust collection electrode 5 is lowered, the electric resistance value is lowered, the back corona phenomenon is prevented, and the evaporation rate is increased.Meanwhile, the wet desulfurization equipment The exhaust gas passing through 4 and 3 dust collecting electrodes is heated and passes through 9
The temperature increases from 0 to 110°C and is discharged into the atmosphere through the flue 6 and chimney 5V. This prevents zero white smoke from being released into the atmosphere from the chimney 5J and has a diffusion effect! enhance

As described above, according to the present invention, the filtered exhaust gas flowing out from the wet desulfurization device is passed into the hollow dust collecting electrode of the electrostatic precipitator σ), and the exhaust gas passing through the inside of the electrostatic precipitator raises S. At the same time, the electric industry 11. * The temperature of the dust adhering to the surface of the dust collection electrode decreases, the electrical resistance of the adhesion duct decreases, and the dust collection rate not only increases, but also increases the temperature of the wet desulfurization equipment outlet gas and releases it into the atmosphere from the chimney. White smoke prevention +1.1-1 Atmospheric diffusion effect 4Iv is increased (・U effect v*-rb-

[Brief explanation of the drawing]

The above is a flow showing a specific embodiment of the present invention. 1... Air heater, 2... Electrostatic precipitator, 3... Dust collection electrode, 4... Desulfurization amount, 5... ·chimney.

Claims (1)

[Claims] In this method, the exhaust gas is passed through an electrostatic precipitator to remove dust, and then passed through a wet desulfurization device to remove the sulfur content. Inside the hollow dust collecting pole...Introducing λ1.2, the canyon drops,
An exhaust gas treatment method characterized by raising the temperature of the exhaust gas passing through the inside of the air collector IIi device and cooling a single collector pole.