工 作 原 理 /The working principle of

Electric tar catcher refers to the use of high-voltage DC electric field to separate the role of tar droplets and gas coke oven gas cooling equipment. The electric tar collector adopts three kinds of structural forms: concentric circle, tube and honeycomb. Regardless of the structure, its working principle is to apply high-voltage direct current between the metal wire and the metal tube wall (or plate) to maintain an electric field sufficient to generate ionization of the gas, so that a corona zone is formed between the yin and the yang. According to the electric field theory, positive ions are adsorbed on the negatively charged corona pole, and negative ions are adsorbed on the positively charged precipitator pole; all the ionized positive and negative ions are filled with the entire space between the corona pole and the precipitator pole. When the gas containing impurities such as tar droplets passes through the electric field, the impurities adsorbed by negative ions and electrons move to the precipitation pole under the action of the coulomb force of the electric field and release the charged charge, and adsorb on the precipitation pole, so as to achieve the purpose of purifying gas, which is usually called charging phenomenon. When the amount of impurities adsorbed on the precipitator increases to greater than its adhesion, it will automatically flow downward and discharge from the bottom of the ionization trap, while the net gas will leave from the upper part of the ionization trap and enter the next process.

结构组成/ Structural components

This product consists of two parts: high-voltage current and electric tar catcher. The former uses various forms of high-voltage DC power supply for electrostatic deposition, while the latter mainly uses FD honeycomb type and WESP wet type in structure. The body of several structures is mainly composed of a cylinder, a discharge electrode (corona pole) and a suction trap (precipitation pole).

The ionization trap consists of two parts: "body system" and "electrical system.

(1) The electrical system consists of "control cabinet", "high-voltage electrostatic silicon rectifier" and "corona pole system.

① High-voltage electric control cabinet: it is the control center of the ionization trap. The power input, working voltage adjustment and output, operation failure alarm and automatic cutting are all completed by the components in the cabinet and the knobs and buttons on the panel. The operation status is displayed by the instrument and indicator light.

② High-voltage electrostatic silicon rectifier: The AC voltage output from the control cabinet is transformed into DC high voltage by boosting and rectification and then transmitted to the corona pole system.

③ Corona system: the main part is corona wire, and is composed of high-voltage porcelain bottle, boom, upper and lower umbrella rings and heavy hammer, etc. The system is installed in the body of the tar removal tower.

When the corona wire is connected to the high voltage, a strong high voltage electric field is generated, and the surrounding gas medium is ionized to generate electric charge, so that the mixture of tar, water mist, dust and the like in the medium is negatively charged.

(2) The body system is the core component of tar removal, and its corona pole system is evenly arranged in each layer of the tower body. When the flue gas is sent from the air inlet to the lower part of the tower body through the gas distribution plate, it flows upward through the middle "precipitation pole" section, and the mixture with negative electricity, such as tar, water mist, dust, etc. Under the action of the high-voltage electric field attraction in this section, these negatively charged mixture is absorbed by the precipitation pole (positive electrode) and collected on the polar plate, then falls down along the polar plate under its own gravity, and discharged regularly, the purified exhaust gas escapes from the upper air outlet of the tower body.

性能特点/The Perfomance charactersticso

The inlet of the ionization trap is equipped with a flow equalizing device in the form of a porous plate and a triangular deflector, so that the flue gas flows evenly through the electric field; the shell is designed to be sealed, rainproof, free of dead corners or dust accumulation areas, and the thickness of the shell wall plate is 4mm; The lower part of the ionization trap is equipped with a manhole. There is a manhole at the top of the dust collector for the maintenance of the electrode suspension system. The diameter of circular manhole door is greater than φ600mm, and the diameter of rectangular manhole door is greater than 500mm × 600mm; The high-voltage part is completely closed and isolated to avoid high-voltage electric shock accident. Insulators are equipped with heat preservation boxes and electric heating devices. All platforms are equipped with guardrails and protective edges. The load of the platform shall not be less than 3KN/m2; the base of the equipment support has taken into account the effect of seismic force acceleration on it; in order to avoid short circuit of flue gas, the ash hopper is equipped with an air equalizing plate, and its lower part is as far as possible from the sewage outlet. The angle between the inclined wall of the ash hopper and the horizontal plane should not be less than 45 ° to ensure the free flow of tar.

Equipment classification

★Concentric circle electric tar collector is composed of several steel plate cylinders with different diameters, with the same vertical axis as the center of the circle, and is sleeved together with the same spacing to form a precipitation pole. Due to the same-sex repulsion between the corona poles. It will make the electric field appear empty small holes, that is, the field strength cave. It is easy to cause short-circuit loss of gas in caves and reduce the trapping effect. At the same time, the concentric circle electric tar collector requires high manufacturing precision and extremely strict installation and debugging. It is easy to change concentricity, levelness and verticality in manufacturing, installation and transportation, which will cause discharge between cathode and anode or other components, making it difficult to reach the required voltage, directly affecting the trapping efficiency of tar, and easily causing breakdown and destruction of electric porcelain bottles. Since the voltage change value of the field strength is 400 V/mm, even if there is a deviation of 1mm between the cathode and the anode, the change value of the field strength voltage can be as high as 400V. Concentric circle electric tar collector has the advantages of large circulation area, low gas flow rate and less steel consumption.

★Tubular electric tar catcher due to the steel pipe and corona wire alone to form an electric field, the field strength voltage depends on the radius of the steel pipe, its value is 400R. Since the tubular electric tar catcher forms an equipolar electric field in each tube section, and there is a vacancy between the tubes, these holes are blocked by the blind area of the tube plate, which reduces the utilization rate of the effective space in the cylinder and reduces the cross-sectional area of the purification channel. This type of electric tar catcher has a large steel consumption, but it is widely used in large and medium-sized gas purification plants due to its advantages of easy manufacturing, equipolar electric field, easy availability of materials and convenient installation and testing.

★Tubular electric tar catcher due to the steel pipe and corona wire alone to form an electric field, the field strength voltage depends on the radius of the steel pipe, its value is 400R. Since the tubular electric tar catcher forms an equipolar electric field in each tube section, and there is a vacancy between the tubes, these holes are blocked by the blind area of the tube plate, which reduces the utilization rate of the effective space in the cylinder and reduces the cross-sectional area of the purification channel. This type of electric tar catcher has a large steel consumption, but it is widely used in large and medium-sized gas purification plants due to its advantages of easy manufacturing, equipolar electric field, easy availability of materials and convenient installation and testing.

Scope of application/Scope of application/

● Oil-containing paraffin waste gas from the production line of the plastic industry;

●The tar-containing smoke produced by the asphalt waterproof linoleum production line;

Tar waste gas produced by foaming and vulcanization production lines in rubber industry;

●The oily waste gas discharged from the textile printing and dyeing industry, the steam cloth machine;

● Organic waste gas discharged from cleaning machines and pellet extruders in the plastic recycling industry;

● Volatile waste gas from printing, painting and painting industries.

It is mainly used for gas purification in asphalt, rubber, chemical fertilizer, coking, city gas, metallurgy, building materials, carbon, ceramics and other industries. At the same time, it removes tar, dust, water mist and other impurities to achieve the dual effects of material recovery and gas purification. It also plays a vital role in ensuring the normal and stable operation of equipment in the rear section of the process flow. In addition, it is mainly used for pretreatment devices for comprehensive organic waste gas treatment.