Baghouse dust collectors
In general baghouses filter by building up a dust cake on their bags. But what is the best way for the filter cake to come off the bag? A compressed-air pulse or a reversed air flow. The choice can affect your energy use and your bag life in different applications.
Definition
An industrial baghouse dust collector is a dry filtration system that separates particulate from an air stream using fabric media, then cleans that media in place rather than replacing it.
Dust-laden air enters a housing filled with filter bags. Particulate accumulates as a cake, usually on the outside of the bag, while clean air passes through the media and out. An integral cleaning system periodically dislodges the cake into a hopper below.
Nederman MikroPul's range of baghouse dust collectors handles foundry / smelter fumes, dust, hot gasses, saw dust, hazardous dusts, chemical by-products, limestone, clinker dust, silica, fine powders, active pharmaceutical ingredients, grain dust, sugar, flour and other food particulates, and combustible dust, among others. Airflow can run from the outside to the inside of the bag or the other way around, depending on the application.
Our baghouse dust collectors employ state-of-the-art filtration media that effectively capture a wide range of particle sizes, from large debris to sub-micron dust. This ensures a cleaner, safer environment for your employees and complies with stringent environmental regulations.
Every industrial process is unique. We offer customizable designs to meet the specific needs of your operation, whether it's heavy dust loads, high temperatures, or abrasive materials.
Designed with energy conservation in mind, our systems optimize airflow and reduce power consumption, lowering your operational costs without compromising performance.
Built with high-quality materials, Nederman MikroPul's baghouse dust collectors are engineered to withstand harsh industrial conditions, ensuring long-lasting reliability.
Our user-friendly designs allow for straightforward access to filter bags and components, reducing downtime and maintenance costs.
Cleaning Methods
Bag filters are designed to be cleaned when they clog, not replaced. Baghouse dust collectors can be cleaned by reverse air or by air pulse. Nederman MikroPul manufactures both types of systems.
A cleaning carriage moves from row to row. Above the cleaning air radial fan, a valve pulses air through a telescopic pipe, inflating each bag and reversing the flow to release the dust cake — without compressed air.
A pulse of compressed air is blasted through the bags to blow loose the built-up particles and maintain optimum filtration efficiency. Used when it is impractical to shut the collector down to clean the bags.
Bags are cleaned by high volume, low pressure reverse air every two minutes. A continuous cleaning system avoids the need for compressed air and unreliable valves entirely.
Selection
| Collector | Cleaning method | Media area / duty | Common applications |
|---|---|---|---|
| Modular pulse jet Mikro-Pulsaire™ | Compressed air pulse | 151 – 8,246 ft² | Size reduction machinery, spray dryers, separators, calciners, mixers, packaging machines, conveyors, chemical manufacturers, foundries, grinders |
| Multi-modular pulse jet sectional | Compressed air pulse | > 4,500 ft² | Kilns, boilers, dryers, mixers, coke pushing systems, sinter strand systems, furnaces, ladle casters, foundry sources, smelters, chemical |
| Round pulse jet cylindrical | Compressed air pulse | High vacuum or high pressure duty | Spray drying, separating, coal grinding, mixing, food manufacturing, rail car loading, product receiving |
| Reverse Air Filter RAF II | Reversed low-pressure air flow | Continuous cleaning no compressed air | Applications where bags need to be constantly cleaned |
| Reverse Air Filter RAF-IS | Reversed low-pressure air flow | Ledge-less housing, no internal electrical components | Highly combustible dust and high temperature: coal (including PRB), wood, agro |
| FS flat bag horizontal | Reversed low-pressure air flow | Gases up to 250 °C | Foundries, steel mills, nonferrous metals, asphalt, galvanizing plants, glass |
Family 1 — Reverse Air Flat Bag
The FS series dust collector with horizontally installed flat bag filters is a compact and efficient filter system with intelligent air cleaning technology. It is ideal for high dust loads of finer dust particles and high gas temperatures.
For plant operators such as foundries, smelters and asphalt producers, the FS flat bag dust collector provides pollution control in a compact and easy-to-install package. The filter type FS is operated with efficient air purging: the purging air filter located behind the purging air fan provides an air pulse which inflates the flat bag during a cleaning cycle and creates an air flow against the filter direction.
Up to 40% space savings compared to typical baghouses
Elimination of compressed air for pulse cleaning
Increased bag life, up to 5 years, based on non-contact cleaning technology
Easy installation and transport to site, typically in a single container-sized flatbed delivery
Guaranteed low emissions
Low wear on parts, with oversight via IoT
Melting and casting furnaces, magnesium treatment, molding lines, casting and cooling lines, shot blasting, casting finishing, sand preparation.
Electric arc furnace, secondary dedusting, flame cutting stations and flame cutting equipment.
Aluminum melting furnaces, AlO2 transport and silos, anode fabrication, copper, copper alloys, magnesium, lead and zinc melting furnaces.
Dry drum, parallel drum, mixers, screens, silos, loading station.
Galvanizing baths with edge extraction or enclosure.
Glass tanks, doghouses, glass fiber production, mineral and glass wool.
Family 2 — compressed air
A pulse jet dust collector is a dry filtration system that incorporates an integral media cleaning system. The media is usually a tubular vertical bag of varying diameter and length. Many bags sit inside a housing and particulate accumulates on the outside.
The cleaning system removes the accumulated cake by blowing high pressure compressed air into the inside of the bag. Nederman MikroPul is the home of the original pulse-jet cleaning patent, granted in 1957. Automated cleaning control systems regulate the pulse of compressed air the bags receive.
Fully assembled Mikro-Pulsaire™ pulse jet dust collectors are ideal for applications requiring filter media area generally between 151 and 8,246 ft². Three access configurations are offered, and the choice is driven by how your maintenance team needs to reach the bags.
RAF II & RAF-IS — reliable cleaning without compressed air
For large applications, generally greater than 4,500 ft² (440 m²) media area, pulse jet baghouse collectors are provided in prewired sections sized to suit shipping limitations. Sub-assemblies can be prepared for bolting and/or welding on site. Compressed air cleaned, with a choice of camlock or snapband bag-to-tube-sheet connection for a leak-free seal.
Nederman MikroPul's round pulse jet dust collectors are for high vacuum or high pressure applications, and are well suited to high internal or external static pressures. They are often chosen for applications requiring explosion protection, and for those with tangential inlets, which reduce bag loading.
On the Mikro-Pulsaire® HP series tangential inlet collector, the inlet acts as a cyclone: the air spins, driving heavy particulate to the walls and then into the hopper before it ever reaches the media. Design pressures range from 17″ w.g. (4250 Pa) up to ASME coded vessels.
Fully assembled horzontal Nederman Mikropul pulse jet dust collectors, with filter area from 110m² - 2300m²
The filter with compressed air cleaning FD is fitted with stationary blowpipes and injection nozzles. Compressed air is supplied from compressed air containers with electromagnetic cleaning valves located outside the filter chambers. Typical applications are energy plants, biomass incinerations, crematory, small air volumes.
Family 3 — reverse air tubular bag
Key to the Reverse Air Filter's high reliability and performance is its simple, effective cleaning system. Bags are cleaned by high volume, low pressure reverse air every two minutes. It is designed for high reliability and operates with lower energy use than an equivalent pulse-jet cleaned system.
The RAF II uses a continuous cleaning system, avoiding the need for compressed air and unreliable valves. Each bag is cleaned once every 120 seconds using the efficient reversed flow of processed air. This complete and systematic cleaning dramatically reduces the pressure drop across the media as well as the load demands on the complete fan system, and bag life is extended because of the cleaning method.
RAF uses two techniques to remove dust: cyclonic separation and media filtration, allowing larger particles to be removed easily before meeting the media. It also reduces the possibility that dust can collect inside the structure, lowering fire and explosion risk.
The RAF-IS Reverse Air Filter is specifically designed for highly combustible dust and high temperature applications, and is ideally suited to coal (including PRB), wood and agro material filtration. It combines high performance, low energy use and reliable reverse-air cleaning in a ledge-less filter housing totally free of internal electrical components.
Gas-phase treatment
A baghouse captures particulate. It does not, on its own, capture acid gases, dioxins or mercury. Additive dosing injects an adsorbent upstream of the collector so the gas-phase pollutant is converted or bound to a solid, and then removed as ordinary dust.
The addition of the adsorbent takes place on the pneumatic way. The hydrated lime is taken out of a silo through a slide gate, a rotary valve and a screw conveyor. In an intermediate vessel the adsorbent is weighed and blown into the ductwork. The dosing quantity can be adjusted by a frequency drive so that the necessary amount of adsorbent can be adapted.
Mostly eliminates acidic pollutants such as sulphurous acid (SO₂), hydrochloric acid (HCl) or hydrofluoric acid (HF). Almost exclusively lime-based products are used here, such as hydrated lime or sodium bicarbonate.
For reducing volatile hydrocarbons, dioxins and mercury. Products such as activated carbon or hearth furnace coke are used; the disadvantage is the explosiveness of these substances. A mixture of carbohydrate and activated carbon may be employed, or a zeolite material. These additives bind the substances above through a very porous structure of about 1000 m²/g. There is no chemical reaction, but a purely physical binding.
Construction lime or stone meal, giving a protective layer for filter bags made of needle felt, or for cartridges.
Often from thermal furnace processes. All acids are chemically converted to salts, which can then be cleaned and disposed of in the filter system as a normal dust filtration process.
Ca(OH)₂ + 2HCl → CaCl₂ + 2H₂O
Ca(OH)₂ + SO₂ → CaSO₃ + H₂O
CaSO₃·H₂O + ½O₂ + H₂O → CaSO₄·2H₂O
Ca(OH)₂ + 2HF → CaF₂ + 2H₂O
Ca(OH)₂ + CO₂ → CaCO₃ + H₂O
Common things to know
Answers to common questions about industrial dust collectors
Connect with Nederman MikroPul to improve your dust collection.
Last updated: August 2026
A baghouse dust collector is an industrial filtration unit that separates particulate from a gas stream using fabric filter bags. The particles are normally captured on the surface of the bag, and the bags are designed to be cleaned when they are clogged rather than replaced. Nederman MikroPul's range suits dusts including wood waste, saw dust, chemical, mineral and combustible dust.
Baghouse dust collectors can be cleaned by manual cleaning, mechanical shaking, reverse air, or by air pulse. Pulse jet collectors blast compressed air through the bag to blow loose the built-up particles. Reverse air filters use a high volume, low pressure reversed flow of processed air.
Pulse jet collectors clean with a short burst of high pressure compressed air fired into the inside of the bag. Reverse air filters clean each bag using reverse air at high volume and low pressure — no compressed air, no pulse valves, no dampers or PD pump to maintain, and in some cases lower energy use than an equivalent pulse-jet cleaned system.
Yes. Collectors receive thorough treatment, as required, in accordance with local standards for prevention of fire and dust explosions, practices for static electricity, deflagration venting, and explosion prevention. Round pulse jet collectors are often chosen where explosion protection is required. The RAF-IS reverse air filter is specifically designed for highly combustible dust and high temperature applications including coal (including PRB), wood and agro materials, using a ledge-less housing free of internal electrical components.
FS flat bag filters handle gas temperatures up to 250 °C. Filter media is selected to suit the application's chemistry, efficiency and temperature requirements.
Additive dosing injects an adsorbent into the ductwork upstream of the collector to treat pollutants that filtration alone cannot capture. There are three basic uses: chemical reaction to eliminate acidic pollutants such as SO₂, HCl and HF using lime-based products; adsorption to reduce volatile hydrocarbons, dioxins and mercury using activated carbon or similar; and a binder such as construction lime or stone meal for oily exhaust air, which protects the filter bags.
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