Description of dust removal plan

The pharmaceutical factory engaged in the production of traditional Chinese medicine granules will produce a large amount of bran-containing powder at the end of the steam dryer. This kind of dust produces a large amount and has a certain viscosity. Explain the solution to the dust removal of the pharmaceutical factory.

Technical Design Notes

After on-site inspection and discussion with relevant technical personnel of the owner, it is determined that the wet dust removal technology is used to treat the gas. The gas is collected by the collection pipeline and enters the wet dust removal tower for purification, and the treated gas is discharged through the chimney. Wet dust removal technology mainly utilizes the solubility of sugar in dust. On the surface of the filler, the powdered sugar is in full contact with the water film to speed up the mass transfer rate and achieve the purpose of dust removal. The exhaust gas temperature is 74°C, which is conducive to the dissolution of powdered sugar.

The equipment is to be arranged on the third floor platform of the drying operation room. The exhaust gas (temperature 60℃-90℃) from the owner's drying equipment passes through the gas collecting pipeline to the wet dust removal equipment of the wet dust removal tower. The wet dust removal tower is equipped with a pre-spray device to remove the waste gas. It contains high concentration dust and has a cooling effect, and the pretreated exhaust gas enters the packing layer. A Pall ring with a specification of φ50 is arranged in the packing layer, and the upper spray water mist adheres to the Pall ring, which increases the contact area with the exhaust gas and improves the removal efficiency of dust in the exhaust gas.

The water after spraying is collected into the circulating water tank below through the action of gravity. Under the action of the circulating water pump, the purpose of recycling is achieved. The bottom of the circulating water tank is provided with a sewage interface, and the saturated wastewater is discharged through the sewage pipeline to the owner's sewer pipeline for centralized treatment. The treated exhaust gas is subjected to secondary treatment by the defogging layer, and after removing the water mist in the exhaust gas, it is discharged to the chimney on the roof of the building through the extraction fan. The treatment efficiency of this equipment for dust is 99%, and the treated exhaust gas meets the emission standard.

This set of equipment is equipped with an accident exhaust system. The accident exhaust system is a pipeline type dry filter, which is arranged in the front section of the wet dust removal tower and is shut off by bursting disc pressure. When the instantaneous pressure in the system is too large or the wet dust removal tower is damaged, the air Press the top to open the rupture disc, and the dusty exhaust gas is discharged into the atmosphere through the bypass pipeline after dry filtration, so as to minimize the pollution value of the accident exhaust air to the atmosphere.

Wet dust removal tower system Flow

Wet dust removal tower is a wet dust removal device, which is a commonly used purification equipment in waste gas treatment projects. The wet dust removal tower is composed of tower body, packing layer, defogging layer, circulating water pump and circulating pipeline. This project uses a wet dust removal tower, which has the characteristics of small footprint, small pressure drop and high treatment efficiency.

The working principle of the wet dust removal tower: the exhaust gas is sucked into the tower body by the centrifugal fan, dedusted and cooled by the imported pre-spraying system, the pretreated gas enters the packing layer, and the aqueous solution is lifted from the circulating water tank to the top of the tower by the pump, and sprayed by the spiral nozzle. After drenching, it adheres to the surface of the filler, and the liquid film formed on the surface of the filler completes the main collection work. The larger specific surface area of the filler provides material conduction between the gas phase and the solid phase. The gas treated by the packing layer flows through the defogging section to block and collect the mist, and then is discharged into the atmosphere.

The material of this equipment is PPH, which is β-modified on ordinary PP material, so that it has a uniform and fine Beta crystal structure, and has excellent chemical corrosion resistance, wear resistance, high temperature resistance, corrosion resistance, aging resistance and j It is an excellent quality product with good affinity, and the temperature tolerance range is -20°C to 110°C.

Water pump

The circulating water power of this system is supplied by the water pump, and the water pump keeps working continuously. The water pump adopts one for use and one for standby. When the running water pump fails, the other water pump can be started quickly. The two pumps operate alternately, and each pump runs for 12 hours. In order to prevent the water pump from dragging the motor and the electric control for a long time and get damp, and to make the wear and tear of each water pump evenly, when the water level is normal, each water pump should be able to automatically work in rotation to ensure that each water pump can be properly maintained. When the water level is dangerous, open the automatic water replenishment valve to replenish water. If a pump fails during startup or operation, the pump should be stopped immediately, stopped for maintenance, and the next pump should be started automatically. Before the fault is cleared, the faulty pump circuit is blocked and exits normal work. It has the most complete protection measures to ensure the safe operation of the equipment. Once a fault occurs, it will be switched immediately and an audible and visual alarm signal will be issued to avoid further expansion of the accident.

Extraction fan

This processing system is planned to be equipped with six extraction fans with an air volume of 7500m³/h. To ensure production, one fan is used and one is prepared. Adopt domestic well-known brands to ensure the quality of operation. The induced draft fan is the power source of the air volume of the wet dust removal system in the drying room, and is controlled by a frequency converter to meet the air volume requirements of various working conditions. The extraction fan is made of FRP material, which is resistant to corrosion, acid and alkali, and is suitable for the treatment of Kangrentang dust and waste gas.

Recommend usage plans and viewpoints

This type of dust collector equipment mainly collects dust through dust removal bags. According to its design principle, it can be divided into three types: mechanical vibration type bag type dust collector, atmospheric backflushing type bag type dust collector and pulse jet type bag type dust collector. kind. It is mainly used to separate granular dust and fine dust in industrial production. The fields involved are: cement, thermal power plants, building materials, asphalt mixers, grain, foundry, metallurgy, mining, chemicals, tobacco, mechanical processing, and boiler dust removal. The disadvantage is that the dust removal efficiency is low, the dust is difficult to clean, and the dust encounters the risk of explosion during the cleaning process.

Cartridge dust collector is a high-efficiency dust collector equipment, which specially solves some disadvantages such as difficult dust collection, poor filtration effect, high filtration wind speed, and difficult dust removal, which makes the dust collector equipment double in operation cost and dust removal effect. The traditional filter cartridge dust collector has two cleaning methods, one is high-pressure airflow backflushing, and the other is pulsed airflow injection.

Wet dust removal is the use of liquid in the dust removal process, mainly water, and the dust-containing gas is in contact with water, and the dust particles remain in the water, in the state of solution or mud, with large contact surface area for water vapor and high treatment efficiency.