Many industrial processes such as grinding and welding produce dust made of different particulates, which can pose a health risk to workers who inhale it. Reports show that indoor air can be polluted up to five times more than outdoor air. Therefore, workers who are exposed to polluted indoor air are at risk of suffering from headaches, respiratory problems or even cancer. To curb this risk, industrial processes should use dust and particle filtration systems. Dust and particle filtration systems refer to systems that are used to separate particles with dust from air or gas. This system is specifically designed to handle large volumes of dust loads released from commercial and industrial processes. Typically, an industrial dust collector system comprises of a dust filter, a blower, dust removal system, and a filter cleaning system.
Dust collector systems are usually used to separate difficult dust properties from the air. Difficult dust properties refer to dust particles that are difficult to handle or separate. In case there is a mixture of liquid and solid particles, it can be described as difficult dust properties. Dust particles can also be said to be difficult to separate if the particles have a small sticking efficiency. Also, particles with poor flowability and cannot be removed from separator or collecting surface are said to be difficult dust properties. Depending on the particle shape and size including flowability, different types of dust collectors can be used. For example, cyclones can be used to remove conductive particles like diesel soot from gases. A wet scrubber may be used to remove small flow rate particles in case it is not economically feasible to use electrostatic precipitators. The following are five main types of dust collector systems that are used in industrial processes.
Cyclones are mechanical dust separators that use centrifugal force to remove high and large volumes of dust particles from industrial applications. Cyclonic separation is used to eliminate particulates like dust and dirt from gas, air or liquid. A hydrocyclone is usually used in eliminating particulate matter from the liquid. On the other hand, a gas cyclone is normally used while removing particulate matter from gas. Cyclones are only used in industrial applications if particles are bigger than 1-10 . Dust contaminated air enters the mechanical unit via the air inlet and flows in a helical pattern before ending at the bottom end of the unit. Inside the inner cylinder, clean air is carried and discharged to the atmosphere.
2. Electrostatic precipitators
Commonly abbreviated as ESP, electrostatic precipitators are filtration devices that are used in industrial applications to remove fine particles such as smoke and dust from a stream of gas. Electrostatic precipitators are usually used for dust or smoke particles that are greater than 1 . An ESP usually consists of different elements that include an ionizing source, dust removal method, an external enclosure, and power supply. This device also has two inlets that serve different purposes. One inlet allows polluted air to enter the device while the other discharges clean air into the atmosphere. The elements in an ESP work together to eliminate dust from the air, store removed dust and discharge clean air. The electrostatic force is the primary force used in an electrostatic precipitator.
3. Wet scrubber
A wet scrubber is a type of dust collector that uses liquid to remove pollutants from gas streams. Usually, the polluted gas comes into contact with the scrubbing liquid so that the pollutants can be removed. The greater the contact of the scrubbing liquid and gas, the higher the dust removal efficiency. Thanks to their versatility, wet scrubbers can be built in different ways which allow maximum contact of the polluted gas stream and scrubbing liquid. This device removes dust particles from polluted gases by capturing the dust in liquid droplets. A wet scrubber that relies on low energy power input is used to collect particles larger than 5 . While high energy wet scrubbers are used to collect small particles of 1 or less.
4. Fabric filters
Fabric filters are devices used to eliminate particulate matter from a gas stream by passing it through a cloth. This air pollution control device traps particulate matter on the fabric surface while clean air is allowed to pass through. Also known as baghouses, fabric filters are particulate removal devices that are used in industrial applications. The ability of a fabric filter to collect micrometer or submicrometer of particles depends on the accumulated dust and not the fabric. Even if the size of the particle is very small, a fabric filter can achieve a particulate collection efficiency of 99 percent or more.
5. High-temperature filtration
Glass fiber materials are commercially used for high-temperature filtration. Other high-temperature filtration elements available today include metal and ceramic. For metal elements, it can operate at a maximum temperature of 600 degrees Celsius depending on the grade of steel used. For ceramic elements, temperature range can go higher than 850 degrees Celsius. It is important to take into consideration the high rate of chemical reactions while operating a high-temperature filtration equipment.