JPS6058251A - Charging method of electric dust colletor - Google Patents

Abstract

PURPOSE:To enhance the coolecting capacity of low resistant dust, by forming an electric field between a dust coolecting electrode and a discharge electrode by flowing a necessary minimum current to dust particles during the charging stop time of intermittent charging. CONSTITUTION:In performing intermittent charging to an electric dust collector by alternately providing a charging time T1 and a charging stop time T2, a necessary minimum current (for example, about 0.1mA/m<2>) is flowed to dust particles as shown by the solid line during the charging stop time T2. By this method, high voltage applied to the electric dust collector is controlled so as to be brought to a voltage wave form as shown by the solid line. Therefore, the reduction of power consumption and the enhancement of collection capacity can be attained.

Description

[Detailed description of the invention] The present invention relates to a method for charging an electrostatic precipitator.

In a conventional electrostatic precipitator (hereinafter referred to as EP), in order to improve the collection performance of, for example, high-resistance dust, and also to reduce the power consumption of the EP, Japanese Patent Application No. 146238/1989 filed by the present applicant has been proposed. No. is proposed. The device described in the specification of Japanese Patent Application No. 54-146238 has a thyristor whose input side is connected to a commercial power supply, whose negative side is connected to the side connected to the output side of the thyristor, and whose output side is an EP opener. A high voltage rectifier connected to the electrode and #1110
．． This EP is characterized by comprising a control circuit for the thyristor that controls charging of the discharge electrode of the EP with a DC high voltage intermittently at a cycle of 0.01 to 1 second.

However, with the intermittent charging method in the conventional EP described above, it is hardly possible to expect an improvement in collection performance, especially for low paper and anti-dust processing, and the energy saving effect is also reduced by 1/2 ( (maintaining performance under normal charging) is at best.

As a result of further testing and research on the conventional intermittent charging method described above, the present inventors have found that during the charging pause time, the minimum necessary low current is passed through the dust particles to create an electric field between the collecting electrode and the discharge electrode. It has been found that the collection performance of low-resistance dust can be improved by forming such a material, and the power consumption when processing low-resistance dust can be reduced.

The purpose is to provide an EP charging method that can reduce power consumption and improve collection performance when processing low-resistance dust in an intermittent charging type EP.

The EP charging method according to the present invention involves passing a minimum necessary low current through the dust particles during the charging pause time of the BP, which performs intermittent charging, to form an electric field between the dust collection electrode and the discharge electrode, thereby collecting low-resistance dust. This technology improves dust collection efficiency at low charge rates (less than 1/2), which was conventionally seen when processing low-resistance dust, and reduces power consumption. It is something.

An embodiment of the method of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a waveform diagram of charging current in an embodiment of the method of the present invention, FIG. 2 is a waveform diagram of charging voltage corresponding to the current waveform shown in FIG. 1, and FIG. 3 is an embodiment of the method of the present invention. FIG. 3 is a characteristic diagram showing the relationship between charge rate and dust collection efficiency in FIG.

In FIG. 1, T1 is a charging time, and T is a charging pause time. The apparatus for carrying out the EP charging method according to the present invention as shown in FIG. A detailed description thereof will be omitted since it is possible to use a device having the following. The above conventional EP
In the thyristor control circuit (for example, as shown by the dotted line in Fig. 1), only a current close to 0 flows during the charging pause time T, and as a result, E
The high voltage applied to Pi2 is controlled to have a voltage waveform as shown by the dotted line in FIG. On the other hand, according to the method of the present invention, even during the load 1 [body retention time T2, the minimum necessary low current is required for the dust particles (this current value can be freely varied) as shown by the solid line in FIG. 1, for example, 0. A current of around 1ynA/+♂ is passed, and the high voltage applied to the EP is the second
It is configured to control the voltage waveform as shown by the solid line in the figure. .

The operation of one embodiment of the method of the present invention will be explained.

Since the method of the present invention is configured as described above,
For example, as shown in Figures 1 and 2, even during the charging pause time T2 of the conventional intermittent charging method, a corona current flows in the EP, and the rainbow dust particles are minimally charged. Moreover, since an electric field above a certain level is maintained between the collecting electrode and the discharge electrode, for example, in the case of low-resistance dust that does not cause reverse ionization, its collection is as shown in Figure 3. Dust efficiency will be improved.

Figure 3 shows the charge rate for low resistance dust. Diagrams T and +T show the relationship between ('/　) and dust collection efficiency.

The dotted line shows the dust collection efficiency when using the conventional intermittent charging method in which no current is applied during 16 hours, and the solid line shows the dust collection efficiency when the minimum current is applied to the dust particles even during 17 hours. It shows the dust collection efficiency when using the invention method. As is clear from FIG. 3, according to the method of the present invention, the above-mentioned predetermined dust collection efficiency does not decrease even during 13 hours. In other words, the charging rate can be set lower while maintaining the same dust collection efficiency, so 1
This means that the power consumption of the EP can be reduced even if a low current is passed for two hours.

According to the method of the present invention, a predetermined low current is passed even during the charging pause time of the EP that performs intermittent charging to form an electric field between the dust collection electrode and the discharge electrode to collect low resistance dust. Second, it has excellent effects such as reducing power consumption of EP and improving collection efficiency when processing low-resistance dust 1. be.

[Brief explanation of the drawing]

FIG. 1 is a waveform diagram of a charging current in one embodiment of the method of the present invention, FIG. 2 is a waveform diagram of a charging voltage corresponding to the current waveform shown in FIG. 1, and FIG. 3 is a diagram of an embodiment of the method of the present invention. OT, which is a characteristic diagram showing the relationship between charging rate and dust collection efficiency in an example, shows charging time, Tt... charging rest time. …Kanjin seat, Tanukijin dialect + M E Takehiko

Claims (1)

[Claims] During the charging pause time of the electric collector that performs intermittent charging, the minimum necessary low current is passed through the dust particles to form an electric field between the collection electrode and the discharge electrode, thereby processing low-resistance dust. A charging method for an electrostatic precipitator, characterized in that: