Abstract: The dryer exhaust gas treatment technology is the difficulty of dust, here introduces several dryer exhaust gas dust removal technology.

Dryer exhaust air volume, high concentrations of dust, moisture large, dew point, easy to condensation, high point of discharge, a wide range of pollution, is the difficulty of the dust removal technology. Dryer tail exhaust with factory conditions related to individual enterprises for drying many materials, production changes, open frequent downtime, large fluctuation range, Furthermore, coal for drying heat source emissions of sulfur the metal oxide structure is corrosive to choose precipitator bring some difficulties.

Cyclone technology

Cyclone technology has low cost equipment that can handle high-temperature gas, easy to operate, suitable for high dust concentration characteristics of the gas. Its working principle is the role of the fan, the dust stream from the inlet at high speed in a tangential direction into the dust collector volute, from top to bottom as the spiral rotary motion, dust particles under the influence of centrifugal force, left behind to the outer wall, and along the lower wall spin, with the contraction of the cone steering axis and by the lower part of the resistance and return, along the axis of bottom-up spiral rotation by core discharge pipe. The outer wall of dust particles in the air stream and gravity driven downward movement along the wall fall into the ash bucket, to achieve the purpose of dust. Since the cyclone is to rely on inertial separation of dust, dust removal efficiency and particle size is proportional to the good effect of dust particle size is large; small particle size, the effect of dust poor, fair treatment of more than 20 microns dust, dust removal efficiency of 70% to 90% .

Bag dust removal technology

Bag filter stable, efficient, easy maintenance and reliable operation is recognized, its particles of 0.1 micron dust gas dust removal efficiency of up to 99%, the dryer exhaust dust bag filter without considering the selection of emission concentration in excess of the problem. Dryer anti-condensation glass fiber bag filter is ideal for dust purification equipment. The device using computer control, sub-room cleaning, regular cleaning, and equipped with temperature detection display, over-temperature alarm device, CW300-FcA using anti-condensation glass fiber filter bag, the bag can effectively prevent condensation, it will not burn bad bag. Hebei Taihang Group diameter of 3 × 24 Mi slag dryer to a dust removal process will be two LFEF7 × 358-HSY / H anti-condensation bag filter, the determination by the environmental protection department, the amount of exhaust gas per hour 42621 standard cubic meters imported dust concentration 69620 mg per standard cubic meter, outlet dust concentration of 147 mg per standard cubic meter, up to the national emission standards. Not only increase production, but also the recovery of dry material, the annual economic benefits of more than 70 million, also received a significant social benefits. However, there is an area of large bag filter, high-investment shortcomings, with the development of the bag laminating technology, this shortcoming will be overcome, the use will be more extensive.

High-voltage electrostatic dust removal technology

High-voltage electrostatic dust removal technology is 50 Hz, 220-volt alternating current into direct current more than 100 kilowatts added to the corona electrode (cathode) forming a non-uniform high voltage electric field, gas ionization to produce large amounts of negative ions and electrons, which enter the field of gas dust charged under the action of the electric force, charged dust tends to the opposite electrode, general anode dust pole, relying on rapping fall into the ash hopper discharge to complete the purifying process dust. High voltage electrostatic precipitator efficiency and low resistance can be widely used in building materials, metallurgy, chemical industry, dust pollution occasions. It handles the high concentration of dust, fine for 001 micron or high resistivity dust, dust effect is more obvious, the series of products to meet different air flow drying equipment, flexible matching for the dryer exhaust dust control characteristics.

Wet dust removal technology

Wet dust removal technology dusty gas by the induced draft fan through the air tube into the lower part of the dust tower, due to the larger cross-section, the flow rate is reduced, and coarse particles of dust first settlement in the gas stream, fine dust with the air rises, spray down the water droplets reverse movement of dust and air flow, the dust is increased wet weight, by gravity, to overcome the decreased lift airflow into the muddy water, into the sedimentation tank through the lower conduit, to achieve the purpose of dust. Muddy water usually after 2 to 3 cycle precipitation level becomes water, pumped into the tower dust recycling, does not cause secondary pollution. The operation is generally positive dust removal technology for drying clay, a variety of objects (original) material drying, easy to mix recycled material can not be used, and the blades wear large. Suzhou cement used on the diameter 2.2 × 12 Mi clay dryer Wet dust removal technology, emission concentration of 132 milligrams per standard cubic meter, up to the national emission standards. Sedimentation tank clean-up once a year, by the wet soil to dry storage, as raw material. The dust collecting system of high efficiency, low resistance, no secondary pollution, flexible technology, reliable operation, low power consumption, investment, non-condensing, adaptable, with good economic and social benefits.

Gravity sedimentation + high-voltage electrostatic dust removal technology

By the settling chamber and the composition of high-voltage electrostatic dust removal technology is dusty gas by the induced draft fan through the duct into the settling chamber speed, bumping into the wall, the airflow direction changes so quickly lower wind speed, particles of dust settling, the delivery device is discharged, fine dust into the air high voltage electrostatic precipitator field, under continuous bombardment of ions and charged, flying dust is discharged after a very collected, purified gas from the duct into the atmosphere. Two dust removal process, primary sedimentation chamber 40 microns or more large particles of dust collection and reduce the dust concentration of gas, will help improve the efficiency of high-voltage electrostatic precipitator dust, wind speed can be larger, the device can be smaller, reduce investment. Zhejiang Lanxi cement dust removal process diameter 22 × 12 Mi clay dryer, dust from the dryer exhaust tail cover by the induced draft fan tube into a square steel plate settling chamber through the air, the exhaust gas after settling into the high-voltage electrostatic dust It is, after purification into the atmosphere. Induced draft fan and settling chamber is installed indoors, electrostatic precipitators installed outdoors, the normal operation of dust removal system, used for many years, non-condensing, measured by the environmental protection department, emission concentration of 48 milligrams per normal cubic meter, lower than the national emission standards.

Tornado + High Voltage Electrostatic Precipitator technology

The dust removal technology is dusty gas from the dryer duct into the top grade high efficiency cyclone pre-dust, dust discharged from the hopper by ash equipment, air dust concentration decreases, then enter the secondary high-voltage electrostatic precipitator dust , a gas turbine after purification into the atmosphere, so that collection efficiency, process flexibility, safety and reliability.

Applications dryer exhaust gas dust removal technology, not only to protect the environment, reduce labor intensity, but also improve the yield when the station, reduced spending sewage charges, the recovered dust is a good cement raw materials, there are significant economic benefits, social and environmental benefits.