What is a Baghouse?
A Baghouse is
a generic name for Air Pollution Control Equipment (APC)
Baghouses are designed around the use of engineered fabric filter tubes, envelopes or cartridges in the dust capturing, separation of filtering process.
Baghouses are NOT VACUUM CLEANERS
The fact that a system can be engineered for almost any dust producing application under almost any set of circumstances puts them into a totally different class.
Because of the wide range of available fabric filters media, the baghouse has proven that it will remain a prime player in the worldwide quest for cleaner air.
Filter Cake
The dust cake accumulation on the surface of the bags s often referred to as the “filter of filtering cake”. This is generally true because we tend to view this dust cake as a filtering element within itself.
If you manage the dust cake performance, you will control the baghouse performance!
Large dust particles create a barrier that can capture the incoming fine particles. Fine particles, 1 micron in diameter or less, are very difficult to deal with. Most “conventional” fabrics have difficulty trapping there “fines” without the assistance of:
- A managed dust cake
- A surface treatment on the filter media intended to act as a barrier or as a dust cake builder.
- A dust cake builder (filter aid) that can be introduced into the system gas stream.
Basic Common Design Elements:
There are many interpretations of how a baghouse should be designed and operated.
Generally, we see the following:
- Compact baghouses with:
- Long bags to provide a large dust drop out chamber.
- Long bags that provide a high cloth area and large dust-setting chamber.
- Compact high cloth area cartridges for large particle drop out capabilities.
There are also many approaches to how fabrics should be utilized in a system:
- In Europe and Asia, we see specific fabrics for specific applications: The Engineered media approach.
- In North America, we tend to favor the “off-the shelf” method: The price approach.
- There is surface filtration.
- There is depth filtration.
- High cloth area compact cartridge filtration
- Then of course, membrane and laminate technology.
Baghouses are flexible in many ways:
- They can come in almost any size to suit any available location or process.
- The fact they have the ability to work in almost any reasonably dry dusty atmosphere is remarkable.
- There are many available parts or retrofits available for almost any make or model.
- They can withstand a lot of abuse and still carry on operating within design specifications.
- There is a large array of filter media available to suit every type of process.
- Most baghouses are only limited by operating temperature and chemical conditions.
- Overhaul costs are relatively cost effective if the machine ins serviced on a regular basis.
General Assessment Guidelines
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We believe the following general guidelines useful whenever we need to review the operation of a baghouse:
- The baghouse is only 1 component of a ventilation system.
- Not all problems in a baghouse are filter media related.
- The dust particles, gas stream and media in a system will produce a characteristic dust cake “profile” for a particular process.
- The dust accumulation on the surface of the bag is usually the most dynamic part of the system.
- The style of bag cleaning system will reflect how the cake is managed.
- The larger the dust drop out area for dust particles before the filter media is impacted, the less stress there usually is on the filtering process.