Bag Filter ppt for information which provide knowledgable

Bag Filter ppt for information which provide knowledgable

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  Bag Filter COMPONENTS ANDTHEIR FUNCTION -WALI MUNEER
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  What is aBag Filter? As the name suggests, it is a filter that looks like bag… But wait…. If it was that simple we would never have thousands of engineers working on it… So definitely it is not a simple filter... So what this bag filter is actually? And where is it used? It’s actually a filter designed to meet the demands of industry. It is used to reduce the emissions from factories.
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  How does itlook? Obviously a bag filter does not look like this in reality.. But you can get an idea about how does it work just by looking at this picture. The components looking like milky bar chocolates are filter bags that traps the dust particles coming from inlet (blue arrow on the extreme left). These filters let the clean air pass through them to the outlet where an outlet fan creates enough suction for the air to flow out of the bag filter through stack. The dust finally falls in hopper (trapezium looking section). Bag filters are fitted inside holes on a sheet called tube sheet.
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  Bag Filter This ishow a bag filter actually looks from outside.
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  Components of bagfilter. Let’s talk about components of bag filter in brief.
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  1. Filter Bag Thisis the key component of a bag filter. It is used to collect dust particles from air when the air passes through it and later that dust is removed from bags by pulsing them. It acts just like a sieve that is used to separate tea from tea leaves. We take into account various factors like Gas temperature, Dust type, Gas volume, Particle size, Flow rate, Pressure, etc.
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  2. Tube Sheet Thisis a tube sheet having holes in which filter bags are fitted. It is made up of single sheet to ensure that there is no leakage and dirty air do not mix with clean air. These sheets are generally made up of mild steel. Below this tube sheet dirty air is present hence we call it dirty air plenum and above this tube sheet clean air is present hence we call it clean air plenum. We ensure that bags are properly fitted so that dirty air does not leaks from dirty air plenum to clean air plenum.
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  3. Cages These colourfulbird-cage looking objects are actually cages that are used to hold filter bags inside bag filter. These are generally made up of mild steel or stainless steel and can be up to 11 metre long. If we hang filter bags directly from tube sheet then they will collapse as soon as air tries to pass through tube-sheet holes. So these cages act like a support to filter bags.
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  Casing Now look atthe rectangular section containing dirt inside. This is actually a cuboidal section which is provided as a region for gas to enter and move upward. The bag filters and cages hang down in this section. Casing is generally made up of mild steel. We ensure that outside dirt is strictly prohibited to enter this area.
• 10.
  Hopper Now looking atthe same image, we can see a trapezium section which is actually a bifurcated pyramidal section in 3D, this section is called hopper. Hopper is used to collect dust that falls from filter bags. Below hopper we provide a device that facilitates the removal of dust from hopper slowly.
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  Pulse jet valves ThisPulse jet valve which is controlled by sequential timer is used for the pulsing of filter bags. It blows filter bags with high pressure and due to this impact dust falls off from filter bags like cake. We generally use two types of pulse jet valves – Right - angle type (Angular valve) and Immersed type.
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  Compressed air header Compressed airheader is used to store compressed air.
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  Blow Tubes Blow tubesare used to carry compressed air from air header to the pulse solenoid valve. They are located in the clean air plenum.
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  Rotary Air Lock Valve Itis a device that rotates slowly to facilitate movement of dust from hopper to outside and prevent the dirt from outside the hopper from entering into the hopper again.
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  Level Switch Level switchis used to indicate the level of dust inside the hopper. It transmits signal to the imcc panel once dust reaches the level where it is fixed. It is fixed at opposite sides of the hopper at different heights to counter variations because of uneven dust accumulation inside hopper.
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  Hopper Heater Inside hopper,dust can absorb moisture and harden. It can resist flow of dust inside hopper. To counter this effect hopper heater is provided inside hopper. Moisture absorbs heat and evaporates which prevents dust from jamming inside hopper
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  Venturi Venturi is usedin bag filters above 5 meters. It is used to increase the impact of pulsing to facilitate the removal of gas. High pressure – low volume type venturi is used to increase the pressure.
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  Explosion Vent Explosion ventsare used to release excessive pressure built inside casing. This pressure can be generated due to explosion caused by combustibles present inside bag filter.
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  ID Fan Induced draftfan is used to suck clean air from the clean air plenum and release the clean air into the atmosphere via stack.