RU2476271C1 - Two-gap electric filter - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to equipment for environmental protection. Proposed filter comprises encased ioniser 2, settler 3 consisting of discharge electrodes 4 and corona-free electrodes 5, and high-voltage source 6. Electric filter is equipped with device to create hydrated ions 7 provided with vessel 8 wit water secured at case bottom and short-circuited annular anode 9 and cylindrical cathode 11 coiled in quartz tube 10. Cylindrical cathode is arranged so that its vertical axis is located perpendicular to airflow direction. Cathode end located in water is connected by current conductor via electronic switch 13 and timer 14 with negative plate of capacitors battery while its opposite end extended above water level by 3…5 mm. Note here that short-circuited anode is connected with positive plate of capacitors battery.

EFFECT: higher quality of cleaning.

2 cl, 1 dwg

Description

The invention relates to equipment for the protection of the environment from dust, soot, smoke and harmful substances in industrial enterprises of the metallurgical, engineering, shipbuilding, construction, chemical, petrochemical, mining, food industries, defense complexes, as well as in power plants of fuel and energy plants, boiler houses of the communal network , as well as for cleaning air from dust in residential and non-residential premises and in administrative buildings.

Known electrostatic precipitator containing a housing with a diffuser and a confuser, precipitation electrodes, corona electrodes, shaking mechanism, power supply, hopper (RU 81103 U1, B03C 3/76, declared. 10.10.2008, publ. 10.03.2009). The disadvantage of this electrostatic precipitator is the increased voltage in the ionizer, which leads to an increase in the installed capacity and consumption of electric energy in the electrostatic precipitator, as well as an insufficient degree of purification of air or gas from dust particles or soot.

Known electrostatic precipitator containing a housing with a diffuser and a confuser, precipitation electrodes, corona electrodes, shaking mechanism, power supply and hopper (RU 84743 U1, B03C 3/76, decl. 30.03.2009, publ. 20.07.2009). The disadvantage of this electrostatic precipitator is the increased voltage in the ionizer, which leads to an increase in the consumption of electric energy in the electrostatic precipitator, as well as an insufficient degree of purification of air or gas from dust particles or soot.

Closest to the claimed device is an electrostatic precipitator containing an ionizer enclosed in a housing, a precipitator consisting of corona and non-corona electrodes installed parallel to the air flow, a high voltage source (RU 2192927 B03C 3/00, decl. 09/21/2000, publ. 20.11.2002) . The disadvantage of this electrostatic precipitator is the insufficient degree of purification of air or gas from dust particles or soot. This is due to the limitation of the charge of particles in the ionizer, since this requires an increase in the potential at the corona electrode, which should be accompanied by an increase in the distance between the electrodes, restrained by the dimensions of the electrostatic filter housing. In addition, an increase in the specified distance leads to an increase in the mean free path of the charged particle to the precipitating surface, which leads to a decrease in particle charge.

The technical task of the proposed solution is to increase the degree of purification of air or gas from dust particles and soot.

The problem is solved in that the dual-zone electrostatic precipitator containing an ionizer enclosed in a housing, a precipitator consisting of corona and non-corona electrodes installed parallel to the air flow, a high voltage source, is characterized by the fact that it is equipped with a device for the formation of hydrated ions containing a fixed in the lower part of the housing a container with water and an annular short-circuited anode located therein and a cylindrical cathode closed into a quartz tube, while One is installed in such a way that its vertical axis is perpendicular to the direction of the air flow, the end of the cathode, placed in water, is connected through an electronic key and timer to a negatively charged plate of the capacitor battery, and the other end of the cathode protrudes above the water level at a distance of 3 ... 5 mm moreover, the short-circuited anode is connected by a current path to a positively charged plate of the capacitor bank.

The dual-zone electrostatic precipitator additionally contains the positions of the upper end part of the cathode and the mechanism for moving the vertical position of the cathode fixed on the photosensor body, connected by a current lead.

In principle, a device is known for producing plasma jets and autonomous plasmoid (hydrated ions), (A.I. Egorov, S.I. Stepanov. Properties of short-lived ball lightning obtained in the laboratory. Journal of Technical Physics, 2008, Volume 78, no. 6, St. Petersburg, Nauka, pp. 15-19), in which, to obtain positively and negatively charged hydrated ions, an electric circuit arrester closes and a direct current flows from the negative pole of the capacitor bank through the current lead to the anode and through ionized air to the ground the surface of the water in the tank. The upper end of the cathode is located above the water level in the tank at a distance of three to five millimeters. When a carbon cathode is wetted with a drop of water and a circuit-breaker is quickly opened and closed, a plasma jet is emitted from the cathode, from which a plasmoid detaches, having a core of positively and negatively charged hydrated ions and a negatively charged shell. After 1-2 s, the shell disappears and positively and negatively charged hydrated ions enter the surrounding air. However, the use of this device for ionizing air or gas particles is not known.

In the proposed electrostatic precipitator hydrated ions are obtained in a device for the formation of hydrated ions. The latter, colliding with neutral particles of dust or soot in the air stream, give them a charge, that is, ionize them.

Studies have shown that when using the inventive electrostatic precipitator for air purification, dust particles and soot particles smaller than 0.5 microns are captured.

The invention is illustrated in the drawing, which gives a General view of the electrostatic precipitator.

The electrostatic precipitator consists of a housing 1, containing an ionizer 2 enclosed in the housing, a precipitator 3, including corona 4 and non-corona 5 electrodes installed in parallel with the air flow, a high voltage source 6, a device for the formation of hydrated ions 7, containing a container 8 with water and with it an annular short-circuited anode 9 and a cylindrical cathode 11 closed in a quartz tube 10. The end face of the cathode placed in water is connected to the current lead 12 through an electronic switch 13 and the timer 14 is negatively charged th plate of the capacitor bank 15. The upper end of the cathode protrudes above the water level at a distance of 3 ... 5 mm. The short-circuited anode 9 is connected by a current path to a positively charged plate of the capacitor bank. The electrostatic precipitator further comprises a photosensor 16 of the position of the upper end part of the cathode, connected by a current path to a mechanism 17 for moving the vertical position of the cathode located outside the capacitance.

The electrostatic precipitator works as follows.

The cleaned air stream or gas containing particles of dust or soot is horizontally directed to the inlet of the housing 1 and enters the ionizer 2, into which hydrated ions are dispersed perpendicular to the stream from the device 7, during which they are ionized by neutral particles of dust or soot. When the timer 14 is turned on, the electronic key 13 is triggered and the electric circuit is closed, consisting of a negatively charged plate of the capacitor bank 15, a current lead 12, a cylindrical cathode 11 closed in a quartz tube 10, water vapor above the cathode, water in the tank 8, and a short-circuited anode 9, connected by a current lead to a positively charged plate of a capacitor bank.

When a drop of water is wetted by the upper end part of the cylindrical cathode 11, a plasma jet takes off from it to a height of 15-20 mm. After 0.1 seconds, the electrical discharge ceases, a plasmoid is formed, which rises perpendicular to the flow of the cleaned air or gas stream. After 1-2 s, the plasmoid membrane disappears and the positively and negatively charged hydrated ions enter the air stream. Upon impact with neutral particles of dust or soot, positively and negatively charged hydrated ions give them a charge, that is, ionize them.

Further, an air stream containing ionized particles of dust or soot enters the space between the corona 4 and non-corona 5 electrodes of the precipitator 3.

In this case, an electric field is created between the corona electrodes connected to the terminal of the high voltage source 6 and the non-corona electrodes connected to the grounded terminal of the high voltage source. Under the influence of the Coulomb forces of the electric field, ionized dust particles or soot are deposited on non-corona electrodes and removed from the cleaned stream of air or gas.

A change in the position of the upper end part of the cathode above the water level is recorded using a photosensor 16, the signal of which is fed to the mechanism for regulating the position of the cathode 17, made in the form of a rack and pinion transmission. If the upper end part of the cylindrical cathode falls below the water level in the tank, then a rack-and-pinion drive (not shown) is turned on and the upper end part of the cathode rises. On the contrary, if the upper end part of the cathode rises above the water level to a height of more than five millimeters, then the rack and pinion drive (not shown) is turned on and the upper end part of the cathode falls down.

Operation of an electrostatic precipitator in an industrial environment can reduce the consumption of electrical energy by reducing the installation capacity of a high voltage source.

The operation of the electrostatic precipitator of the proposed design was tested in a production environment. During the operation of the electrostatic precipitator installed on the welding section of the workshop for the production of metal pipe welding, the degree of purification of air from soot particles amounted to 99.5%.

Claims (2)

1. Two-zone electrostatic precipitator containing an ionizer enclosed in a housing, a precipitator consisting of corona and non-corona electrodes installed in parallel with the air flow, a high voltage source, characterized in that it is equipped with a device for the formation of hydrated ions, containing a container of water attached to the bottom of the housing and the cylindrical short-circuited anode located therein and the cylindrical cathode closed into the quartz tube, while the cylindrical cathode is mounted so that its the vertical axis is perpendicular to the direction of the air flow, the end of the cathode placed in the water is connected via an electronic switch and a timer to the negatively charged plate of the capacitor battery, and the other end of the cathode protrudes above the water level at a distance of 3 ... 5 mm, and the short-circuited anode is connected to positively charged capacitor bank plate. 2. The dual-zone electrostatic precipitator according to claim 1, characterized in that it further comprises a position sensor of the upper end part of the cathode and a mechanism for displacing the vertical position of the cathode fixed on the casing, connected by a current lead.