[Spray cleaner]
Spray dust collector: in the dust collector, water sprays through the nozzle into a mist. When the dust-containing smoke passes through the mist-like space, due to the collision, interception and cohesion between the dust particles and the droplets, the dust particles follow the droplets. Landing down. The dust collector has a simple structure, low resistance and convenient operation. The outstanding advantage is that the dust collector is provided with a small gap and aperture, which can handle the smoke with higher dust concentration without causing plugging. Because it sprays droplets thicker, there is no need for mist-like nozzles, so that the operation is more reliable. The spray-type dust collector can use recycled water until the particulate matter in the washing liquid reaches a very high level, which greatly simplifies Water treatment facilities. Therefore, such dust collectors are still used by many companies. Its disadvantage is that the equipment has a relatively large volume, the ability to process fine dust is relatively low, and the amount of water to be used is relatively large, so it is commonly used to remove flue gas with large dust particle size and high dust concentration.
The commonly used spray dust collector is divided into three structures according to the flow pattern of gas and liquid in the dust collector:
Spray downstream, ie gas and water droplets flow in the same direction
Counter-current spraying, that is, liquid spraying against the air
Cross-flow spray, which sprays liquid in the direction perpendicular to the air flow.
[Bag filter]
The working mechanism of the bag filter is that the dust-containing flue gas passes through the filter material, the dust particles are filtered, the filtering material collects the coarse-grain dust mainly by inertial collision, and the collection of the fine-grain dust mainly depends on diffusion and screening. The dust layer of the filter also has a certain filtering effect.
The advantages and disadvantages of bag filter dust removal are related to many factors, but mainly depend on the filter material. The filter material of the bag filter is synthetic fabric, natural fiber or glass fiber woven cloth or felt. If necessary, sewn cloth or felt into a cylinder or a flat filter bag. Depending on the nature of the flue gas, filter media suitable for the application conditions are selected. Generally, when the flue gas temperature is lower than 120°C and the filter material is required to have acid resistance and durability, polyester fleece and polyester needle felt are often used; when high-temperature flue gas (<250°C) is processed, graphitization is mainly used. Glass cloth; in some special circumstances, the use of carbon fiber filters.
It is important to control the speed at which the flue gas passes through the filter material (called the filtration rate) during operation of the bag filter. Generally, the filtration rate is 0.5-2 m/min, and the particle efficiency greater than 0.1 μm can reach more than 99%, and the device resistance loss is about 980-I470Pa.
[Venturi Tube Dust Collector]
Venturi tube dust collector consists of two parts: Venturi tube agglomerator and demister. The venturi agglomerator consists of a shrink tube, a throat tube and a diffuser tube. When the flue gas enters the shrink tube, the flow rate gradually increases. When the flue gas enters the throat, the flow rate reaches a maximum, and pressure water is added to the throat. Due to the rapid atomization of water under high-speed airflow, dust particles in the flue gas are forcibly wetted and condensed. The diffusion tube condensation process continues. Finally, the dust-laden water is separated in the demister to achieve the entire process of dust removal.
There are many demisters behind the Venturi tube, such as gravity dehydrator, elbow dehydrator, cyclone dehydrator, cyclone dehydrator, impact dehydrator and so on. When selected, it can be based on the reliability of the work, the degree of atomization of the liquid, the need to absorb harmful gases and economic considerations.
Venturi tube dust collector has the advantage of being able to handle high dust concentrations of flue gas, and can remove 0. 05-100μm dust, the efficiency of up to 99%. However, because of its large pressure loss and high energy consumption, it is generally used only for the treatment of smoke with fine dust or high temperature.