JPS63190665A - Operation of electrostatic precipitator - Google Patents

Abstract

PURPOSE:To prevent the re-scattering of dust at the time of the sharp increase of an output current, in an electric precipitator having a dust collection chamber divided by a plurality of gas passages, by repeating the charge ON/OFF operation of the dust collection chamber during a period when a part of the gas passages is closed. CONSTITUTION:In the operation of an electric precipitator, for example, when a gas passage 6A is closed, the other gas passages 6B-6D are opened and the hammering of dust collection chambers 1A-1D, 2A-2D is successively performed. At the time of the hammering of the dust collection chambers 2A-2D, the inlet dampers 3A-3D and outlet dampers 4A-4D of the electric precipitator and power source apparatuses 8, 9 operate in conjunction with a hammering apparatus. At the time of the closure of the gas passage 6A, re-charging, the stoppage of charging, charging and the stoppage of charging are repeated after the first sedimentation time of dust after the finish of hammering, and the outlet damper 4A and the inlet damper 3A are successively opened through the second sedimentation time and, after completion, gas is transferred to an adjacent dust collection chamber 2B.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides an electrostatic precipitator having a dust collection chamber separated by a plurality of gas passages and a power supply device that charges the dust collection chamber with a high DC voltage. Regarding the operation method, especially when some gas passages are closed, the charge in this dust collection chamber is turned on and off multiple times.
The present invention relates to an operation method for forming an operation control signal that repeats.

[Conventional technology]

A conventional method of operating this type of electrostatic precipitator will be explained using a thermal power plant as an example.

FIG. 1 is a schematic diagram of an electrostatic precipitator for purifying boiler exhaust gas in a thermal power plant.

Depending on the boiler side conditions or operating conditions, the electrostatic precipitator may
It is divided into two series or composed of one series.

The following explanation will be made for the case of l series for simplicity.

The electrostatic precipitator includes a dust collection chamber 1.2 consisting of a discharge electrode, a dust collection electrode, and a hammering device, and an inlet and outlet gas passage 6, 7 separated by an inlet damper 3, an outlet damper 4, and a partition plate 5. Furthermore, a DC power supply device 8 that charges the discharge electrode part of the dust collection chamber with DC high voltage,
The exhaust gas from the boiler is guided into the electrostatic precipitator via the inlet flue 10, and the clean gas with dust collected passes through the outlet flue 11 and is released into the atmosphere from the chimney.

Figure 2 is a diagram of how to operate an electrostatic precipitator, Figure 3
The figure is a partially enlarged view of FIG. 2, and in both figures, the horizontal axis T indicates the time axis.

In order to prevent the collected ash from being re-dispersed when hammering the dust collecting chamber 2A and generating visible smoke from the chimney, the dust collecting chamber 2A is installed.
When hammering, the inlet damper 3A and the outlet damper 4A are completely closed to close the gas passage 6A and prevent gas from flowing into the dust collection chamber 2A.

That is, in the case of FIG. 1, the total gas amount is transferred to the gas passage 6B,
Flow into 6C and 6D. As soon as the outlet damper 4A is fully closed, the dust collection chamber 2A stops being charged for (t4-)-t5), and
It is configured so that after hammering for 4 hours and completing the first dust settling time t5, the dust is transferred to the adjacent dust collection chamber 2B.

As a similar example, (1) Charging does not stop during the hammering time of dust collection chamber 2A.

(11) When the dust collection chamber IA is hammered, charging of the dust collection chamber IA is stopped in the same way as when the dust collection chamber 2A is hammered.

Other methods may also be used.

Normally, the size of this type of electrostatic precipitator, the number of gas passages, and the operation interval shown in Figure 2 are planned assuming the maximum amount of gas that can flow into the electrostatic precipitator and the maximum dust landscape. , when the boiler is operated under a light load or when fuel with low dust generation is used, the hammer opening interval T2 of the dust collection chamber 2A is
The power supply units 8 and 9 were operated by setting the output currents to be long and suppressing the output currents of the power supplies 8 and 9 from the viewpoint of power saving.

In such operation, when the load on the boiler increases or when the output current of power supplies 8 and 9 is suddenly increased during the soot process, the dust that has accumulated in the dust collection chambers 1 and 2 of the electrostatic precipitator will be removed due to the sudden increase in the output current. Due to the influence of ion winds, it may be re-dispersed and confirmed as visible smoke from chimneys.

[Problem that the invention seeks to solve]

The object of the present invention is to solve the problems of the prior art, as shown in FIGS. 2 and 3. To provide a method of operating an electrostatic precipitator which increases the effect of removing adhering dust during hammering and reduces the amount of re-splattered dust when the output current of a power supply device is suddenly increased during an increase in boiler load or temporary soot profiling.

[Means for solving problems]

This invention confirms that the re-scattering of dust when the output current of a power supply device increases rapidly is due to the ion wind of the dust that has adhered and accumulated in the dust collector, and reduces the amount of this adhered and accumulated dust.
That is, as a means of increasing the peeling effect during hammering and eliminating adhering and accumulated dust, the charge in the dust collection chamber is turned on and off several times while some of the gas passages are closed. The hand movement control signal is configured as follows.

[Embodiment] Fig. 4 shows a diagram of an embodiment of a method of operating an electrostatic precipitator according to the present invention.

For example, in FIGS. 1 to 4, when the gas passage 6A is closed, the other gas passages 6B and 6C.

6D is open circuit. Dust collection chamber IA-I of electrostatic precipitator
The hammering steps D and 2A to 2D are performed sequentially as shown in FIG. When hammering the dust collecting chambers 2A to 2D, as shown in FIGS. 3 and 4, the inlet dampers 3A to 3D and the outlet dampers 4A to 4D of the electrostatic precipitator are used.

Power supplies 8 and 9 are configured to operate in conjunction with the hammering device. When the gas passage 6A is closed, it is generally configured as shown in FIG. 3, but in this embodiment, after the first settling time t5 of dust after hammering, recharging, charging pause, and re-recharging are performed. Repeat charging, charging pause, and charging ON-OFF, second sedimentation time [t6-t) x n times-tsX(n-1)
After the completion of charging, the outlet damper 4A is opened, the inlet damper 3A is opened, and after the charging is completed, the charging chamber 2B is moved to the adjacent dust collection chamber 2B. Each is set for a few seconds. In addition, due to the charging, the effect of blowing away the dust that was not removed by the hammering for t4 hours and the dust that had newly adhered and accumulated in the dust collection chamber as a result of the hammering was obtained.

〔Effect of the invention〕

This invention provides a time period during which a part of the gas passages of an electrostatic precipitator has a dust collection chamber divided by a plurality of gas passages and a power supply device that charges the dust collection chamber with a DC high voltage. Since we have adopted an operation method that forms an operation control signal that repeats the power ON and OFF of this dust collection chamber multiple times, the collection can be easily performed when the boiler load increases or when the output current of the temporary DC power supply of the Soot Pro increases rapidly. The peak value of ant dust at the exit of the dust device is I
It can be lowered to below A.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an electrostatic precipitator for purifying boiler exhaust gas in a thermal power plant to which the operating method according to the present invention is applied, and FIG. 2 is a diagram of an example of the operating method of the electrostatic precipitator. 1.2...Dust collection room. 6A...Closed gas passage. 6B, 6C, 6D...Open gas passages. Fig. 1 1.2 --- ME room 6A --- M path east force wound 1 each 6B, 6C, 6D --- Ichisho Yoshiyuki 1 Girth I 1 Fig. 3 Fig. 4

Claims (1)

[Claims] 1. A method for operating an electrostatic precipitator having a dust collection chamber separated by a plurality of gas passages and a power supply device that charges the dust collection chamber with a high DC voltage, A method for operating an electrostatic precipitator, which comprises forming an operation control signal that repeats charging ON and OFF of the dust collecting chamber a plurality of times during a time when a passage is closed.