Dust Collection Systems

Safely operating dust collection systems has become increasingly complicated over the last decade. New regulations from OSHA and the NFPA have sought to improve the safety of collecting combustible and explosive dusts. A dust collection system helps keep your shop clean and will protect your health. Smaller dust collection systems use a single-stage vacuum to perform suction and filtration the dust is drawn into an impeller and collected in a container. Air is recirculated into the shop after passing through a filter to trap smaller particulate. Larger systems utilize a two-stage system separating large particles from fine dust, then drawing the air through the impeller. The air is then exhausted outsides or to a filtering system and recirculated back indoors.

 Designing and operating a safe and effective dust collection system begins with a complete and comprehensive analysis of your dust that identifies the general characteristics as well as the associated hazards. Establishing basic information such as the bulk density (specific gravity), terminal velocity, particle size distribution, and moisture content will allow the collection system to be properly sized. Part of this analysis should also include determining whether the dust is combustible or explosive in accordance with current NFPA standards. This is one of the most commonly overlooked steps because of the associated up-front cost. However, avoiding this step or using incorrect information can have dangerous consequences. Also, it’s important to take the time to review the MSDS sheets (if available) for other potential hazards and guidance on how to handle the collected material.

A fully operational dust collection system is comprised of the hood or capture device, the ducting system, the dust collector and the air moving device. If any one of these components is not designed with the dust characteristics and hazards in mind, the entire system safety is in jeopardy. Manufacturers often believe that simply having a dust collector equipped with an explosion vent is adequate protection but they ignore the important considerations of the complete system. For example, poorly designed ducting that does not maintain proper conveyance velocity during operation creates performance and safety hazards where dust build-up can result in fire hazards or even structural failure.

Systems must also be properly maintained in order to achieve the desired level of consistent performance and safety. Filter changes, removing dust build-up on hoods, pressure gauge accuracy, airflow validation and non-obstructed explosion vents are just a few of the items which should be regularly checked to help ensure ongoing safe operation. In addition, operational and maintenance staff should be sufficiently trained and have a solid understanding regarding what the target system performance is, how to verify this performance and how to service the equipment when necessary.

   

Investments in dust collection systems are intended to provide protection to your company’s most valuable assets - your workers and your facility. Dealing with combustible and explosive dust hazards come with associated additional costs but the risks of not adequately addressing the issue are much greater. The amount of publically available information available combined with the documented examples of property damage and loss of life from dust explosions should compel manufacturers to take the necessary steps to ensure that their dust collection systems are safe. And, dust collector manufacturers are willing and eager to help with the education process so be sure to tap into their expertise and knowledge regarding dust collection system safety when you are considering vendors to meet your specific dust collection needs.

dust extraction

Dust and Fume Extraction

  Dust and fume extraction systems are machines that are used to remove dust and other micro and macro particles from the environment. They clean the air therefore protecting people from diseases and also the industry from hazards like fires caused by dust.

These machines are mostly found in industries because it is likely that you find dust or other micro and macro particles caused by the machines in that industry. With them installed they will keep workers safe. If you do not keep them safe then they are likely to conduct diseases and they will bring suits in court against you. In the past industries have lost cases and have had to pay big fines.

One should not think only of the factories having these but also places where people work. To avoid stuffy places, it has been made compulsory to install them. Failure to which leads to imposition of code violation find so as to act as an example to others.

Soot extractors are also essential in places where soot is emitted. In places where this is produced, soot causes a great risk. Some soot particles are combustible and thus can catch fire. In the past, factories have been grazed to the ground because of soot fires. Fixing this will help confine the soot.

Other dust and fume extraction systems include soot extractors. Soot is very risky in a working place. Depending on the components of the soot, it can easily catch fire and explode. This can cause major loses to an industry. These machines will help trap and store soot.

In areas where these dust and fume extractors are not installed, people are prone to soot related diseases. These are asthma, lung cancer and others. It is very costly to treat them and in some instances it can cause deaths. To ensure that people are not affected it is important to fix these machines.

There are different types of dust and fume extraction machines, for example the shot blasting system which is mostly used where fine dust is mostly released to the atmosphere. The other is powder point system which is a dry process where materials are released to the atmosphere due to overspray.

The thermal spraying systems also work like the one mentioned above. It gets the particles released to the atmosphere also because of overspray. When purchasing these machines, it is good to know what they do. They have different purposes. Maintenance is also of essence to these units. An expert is needed when it comes to installing the dust and fume extraction systems. This is because a layman cannot do or manage to install it. If it is not fixed properly it can cause catastrophic effects. One should indulge a specialist so as to avoid unnecessary expenses such as repairs and money to pay the expert.

The advantage of having this person is because he will be able to inform you on different types and which types to go for. He will be of essence when he comes to servicing it.

The person who is to install it will also give you guidelines on which type to buy. He will also be ensuring that Welding fume extractor is well serviced and will inspect it on any damages. A new design of these dust and fume extraction systems has been manufactured. This one can handle explosive substances like titanium. This will also prevent these investments from catastrophic events such as explosions.

dust reduction

Dust Reduction and Extraction

Dust reduction is the science of reducing harmful dust emissions by applying sound engineering principles. Properly designed, maintained, and operated dust reduction systems can reduce dust emissions and, thus workers' exposure to harmful dusts. Dust reduction systems can also reduce equipment wear, maintenance, and downtime; increase visibility; and boost employee morale and productivity. The saying "prevention is better than cure" can certainly be applied to the control of dust. Although total prevention of dust in the bulk material handling operation is an impossible task, properly designed bulk material handling components can play an important role in reducing dust generation, emission, and dispersion. After all the necessary preventive measures have been adopted, the dust still remaining in the workplace can be controlled by one or more of the following techniques: dust reduction systems, wet dust suppression systems, and airborne dust capture through water sprays.

Dust collection systems are industrial ventilation principles to capture airborne dust from the source. The captured dust is then transported to a dust collector, which cleans the dusty air. Wet dust suppression systems use liquids (usually water) to wet the material so that it has a lower tendency to generate dust. Keeping the material damp immobilizes the dust, and very little material becomes airborne. Airborne Dust Capture through Water Sprays technique suppresses airborne dust by spraying fine droplets of water on the dust cloud. The water droplets and dust particles collide and form agglomerates. Once these agglomerates become too heavy to remain airborne, they settle from the air stream.

Many types of dust and fume are hazardous to health if inhaled. People can become permanently sensitized to fumes which mean that continued exposure, even to very small amounts of fume, may cause asthma attacks or other respiratory diseases. Dust and Fume extraction systems are installed to capture the fumes & unburnt particles of material which is generated during various processes. The Dust and Fume extraction system consists of suction hoods, swivel hood for standby furnace; hood required during pouring and other types of hood required at different processes with ducting’s & butterfly dampers. Centrifugal ID fan is also provided as a part of the Dust and Fume Extraction system (FES). Dust and Fume extraction systems can capture the dry dust. These systems create safe & clean environment to work. Fume extraction systems are user friendly and they have maintenance free operations.

The dust and fume extraction systems provide dust free, fumes free and clean atmosphere in the application area and are very simple to use. The industries in which these systems are catered to are as follows: • Rubber and plastic moulding industries • Foundries • Chemical process industries • Pharmaceuticals • Heat treatment plants • Chemical treatment plants • Steel • Cement • Power plants. These systems are also excellent for operations like welding, soldering, vapor control with solvent ink printing and many other industrial uses requiring effective fume and particle control. Dust and Fume extraction systems come standard with maintenance free high performance turbines with a digital control interface to monitor filter performance, airflow, operating hours and more.

Air Pollution Control

Air pollution occurs when the air contains gases, dust, fumes or odour in harmful amounts. That is, amounts which could be harmful to the health or comfort of humans and animals or which could cause damage to plants and materials. The substances that cause air pollution are called pollutants. Pollutants that are pumped into our atmosphere and directly pollute the air are called primary pollutants. Primary pollutant examples include carbon monoxide from car exhausts and sulfur dioxide from the combustion of coal. Concerns about global air pollution levels are increasing, and for business owners feeling the pressure, the growing area of air pollution control can be pretty cloudy itself.

Volatile Organic Compounds (VOCs)

One of the major causes of both indoor and outdoor air pollution is Volatile Organic Compounds (VOCs). VOCs are found within a wide range of consumer products, including solvent-based paints, printing inks and petrol products. Due to the proven contribution of VOCs to air pollution (and ultimately smog) VOC control regulations are enforced around the world to protect the environment against them.

Activated Carbon

Activated Carbon is a popular air pollution control method. One of the most common forms of carbon treatment in air pollution control is carbon adsorption. This method sees the use of dry chemical scrubbing media such as carbon filters for the adsorption of fumes from the air.

Biofilters: Clearing the Air

Biofiltration is a method of air pollution control in which process pollutants are biologically degraded using microorganisms. The most common air pollution control application of bio filters is the microbiotic oxidation of contaminants in the air. Bio filters use living materials to degrade pollutants when immobilized in the biofilm. Applications of this method include treatment of the off-gas from wastewater treatment plants, after painting and during the manufacture of food products. 

Although capable of treating large airflows, one of the disadvantages of biofilters is the requirement of a large amount of physical space. In recent years efforts have been made to reduce the amount of space needed, meaning that footprint reductions have been seen.

Various systems are used to ensure that sufficient moisture levels are maintained throughout the system. Air is humidified before entry to the bed using humidification chambers, bio scrubbers and water spray systems. Bio filters are cost-effective and straightforward options for pollutants capable of biodegrading reasonably easily. The absence of further pollution from bio filters is another positive associated with this method of air pollution control. 

Driving Towards Cleaner Emissions

Car engine emissions are recognized as one of the leading causes of air pollution. Catalytic Oxidizers are placed in the exhaust system of cars to reduce emissions from the exhaust pipe. The ideal byproducts of a car’s engine are carbon dioxide, some water and nitrogen. However in reality engines continue to release unburned hydrocarbons which damage the environment. Catalytic oxidizers now oxidize many of the unburnt hydrocarbons from an engine, leading to cleaner emissions from cars. 

Dust Collection

Dust Extraction & Collection: Live Safely in Dusty Environments

Dust is a term used to describe all airborne particles – these can be wood, stone, flour, concrete, grain, mold or asbestos particles as well as fumes and chemicals. Many activities create dust. Larger dust particles get lodged in the nose and throat while the smaller more dangerous particles get lodged deep in the lungs – these dust particles are the ones that can cause fatal diseases. It is a legal requirement to assess and monitor the dust risk in a work environment where the creation of dust is “part of the job”. After the risk is assessed, dust extraction and suppression equipment can then be installed and utilized. In order to lower your risk in terms of dust exposure attempt to implement the following ideas – try to avoid creating dust by investigating different ways of doing a dust-creating job; try to prevent your exposure to dust or use dust extracting methods and equipment; however, if it’s not possible to avoid dust completely, try to minimize your exposure as much as possible. Remember, dust is dangerous – work safely.

A dust collector is a system used to enhance the quality of air released from industrial and commercial processes by collecting dust and other impurities from air or gas. Designed to handle high-volume dust loads, a dust collector system consists of a blower, dust filter, a filter-cleaning system, and a dust receptacle or dust removal system. It is distinguished from air cleaners, which use disposable filters to remove dust.

Five principal types of industrial dust collectors are:

·         Inertial separators

·         Fabric filters

·         Wet scrubbers

·         Electrostatic precipitators

·         Unit collectors

Dust collectors vary widely in design, operation, effectiveness, space requirements, construction, and capital, operating, and maintenance costs. Each type has advantages and disadvantages. However, the selection of a dust collector should be based on the following general factors:

·         Dust concentration and particle size - For minerals processing operations, the dust concentration can range from 0.1 to 5.0 grains (0.32 g) of dust per cubic feet of air (0.23 to 11.44 grams per standard cubic meter), and the particle size can vary from 0.5 to 100 µm.

·         Degree of dust collection required - The degree of dust collection required depends on its potential as a health hazard or public nuisance, the plant location, the allowable emission rate, the nature of the dust, its salvage value, and so forth. The selection of a collector should be based on the efficiency required and should consider the need for high-efficiency, high-cost equipment, such as electrostatic precipitators; high-efficiency, moderate-cost equipment, such as baghouses or wet scrubbers; or lower cost, primary units, such as dry centrifugal collectors.

·         Characteristics of airstream - The characteristics of the airstream can have a significant impact on collector selection. For example, cotton fabric filters cannot be used where air temperatures exceed 180°F (82°C). Also, condensation of steam or water vapor can blind bags. Various chemicals can attach fabric or metal and cause corrosion in wet scrubbers.

·         Characteristics of dust - Moderate to heavy concentrations of many dusts (such as dust from silica sand or metal ores) can be abrasive to dry centrifugal collectors. Hygroscopic material can blind bag collectors. Sticky material can adhere to collector elements and plug passages. Some particle sizes and shapes may rule out certain types of fabric collectors. The combustible nature of many fine materials rules out the use of electrostatic precipitators.

·         Methods of disposal - Methods of dust removal and disposal vary with the material, plant process, volume, and type of collector used. Collectors can unload continuously or in batches. Dry materials can create secondary dust problems during unloading and disposal that do not occur with wet collectors. Disposal of wet slurry or sludge can be an additional material-handling problem; sewer or water pollution problems can result if wastewater is not treated properly.

Dust collectors are used in many processes to either recover valuable granular solid or powder from process streams, or to remove granular solid pollutants from exhaust gases prior to venting to the atmosphere. Dust collection is an online process for collecting any process-generated dust from the source point on a continuous basis. Dust collectors may be of single unit construction, or a collection of devices used to separate particulate matter from the process air. They are often used as an air pollution control device to maintain or improve air quality.

Dust collectors remove particulate matter in the form of fine liquid droplets from the air. They are often used for the collection of metal working fluids, and coolant or oil mists. Mist collectors are often used to improve or maintain the quality of air in the workplace environment.