Volatile Organic Compounds (VOCs) and dust are key pollutants in many industrial sectors, with environmental implications and health risks. These emissions are particularly prevalent in the chemical, pharmaceutical, automotive, wood, plastics, paint, coatings and food industries.
Every industrial process, from the handling of raw materials to final manufacture, contributes to the release of these substances into the atmosphere. These emissions can be simultaneous or sequential, depending on the specifics of the industrial operations and the materials used. The emission of VOCs and dust is often accompanied by odor nuisance and can present a risk of explosion (ATEX), which requires rigorous management and appropriate preventive measures to minimize the impact on the environment and public health.
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- VOC and dust emissions in the chemical and pharmaceutical industries. Odors and associated ATEX risks.
- Odor nuisance associated with VOC and dust emissions in the chemical industry
- ATEX risk associated with VOC and dust emissions
- Dust and VOC emissions in the automotive industry. Odors and related ATEX risks.
- VOC and dust emissions in the wood industry. Olfactory nuisance and related ATEX risk.
- Dust and VOC emissions in the plastics industry. Odor nuisance and ATEX risk generated.
- Dust and VOCs emitted in the paint and coatings industry. Odors and induced ATEX risks.
- VOC and dust emissions in the food industry. Olfactory nuisance and related ATEX risks.
VOC and dust emissions in the chemical and pharmaceutical industries. Odors and associated ATEX risks.
What operations emit dust and VOCs in the chemical industry?
In these sectors, several industrial processes emit VOCs and dust simultaneously, or within a short space of time. These emissions occur during the movement, use or manufacture of chemical materials. Here are a few examples of operations.
Logistics operations
The unloading, handling and storage of raw materials in powder or granulated form generate dust. If these raw materials contain VOCs, they may emit them during these operations.
Material operations
Mixing or grinding solid chemical substances produces fine particles that become airborne. If these substances contain volatile organic compounds, VOCs will be emitted simultaneously.
Chemical synthesis
During chemical synthesis, the reaction process can produce solid particles, by-products of the reaction. Similarly, the use of reagents and solvents, or the generation ofoff-gases, contribute to VOC emissions.
Drying and heating operations
These operations can generate both particles and VOCs, since they often involve evaporating solvents and obtaining dry products. Gas flow from solvent evaporation and product movement during drying can lead to the formation of particles.
Packaging of VOC- and dust-generating products
The packaging and conditioning of powdered or granulated chemical products will generate dust and VOCs if these products contain them.
Odor nuisance associated with VOC and dust emissions in the chemical industry
In addition to the risks associated with dust and VOCs, some of these chemical substances also cause odor nuisance. These producers of unpleasant odors include :
Solvents and organic compounds used in various chemical processes, or their interaction with other chemical substances, emit :
- aromatic VOCs such as: toluene(sweet, pungent odor like gasoline), xylene(same as toluene, but more pungent and stronger), benzene(sweet, aromatic odor), naphthalene(mothball odor)…
- Oxygenated VOCs such as acetone ( pungent, fruityodor , reminiscent of nail polish and nail polish remover), isopropyl alcohol(alcoholic odor of methylated spirits), formaldehyde(pungent, pungent, irritating, chemical odor) acetaldehyde(pungent, irritating odor with a sweet note),
- sulfur-containing VOCs such as mercaptan(rotten egg smell),
- nitrogenous VOCs such as pyridines (pungent, unpleasant, medicinal odor), aniline (pungent, slightly nauseating odor) and other amino VOCs(pungent, fishy odor, characteristic of amines).
ATEX risk associated with VOC and dust emissions
Most of these VOCs, emitted by chemicals used as raw materials, reagents, solvents, intermediates, by-products of chemical synthesis, or reaction by-products, present an ATEX risk. This ATEX risk arises from operations such as those described above. The operating context will be taken into account by the manufacturer when selecting the device.
Conclusion
Preventing joint emissions of VOCs and dust requires the use of equipment combining filtration of each type of pollutant; or, if emissions are separate in the same workshop, a combination of equipment specializing in VOC or dust filtration .
What operations emit VOCs and dust in the automotive industry?
Several operations, located in the same production volume, can emit particles and volatile organic compounds simultaneously or successively. Here are a few examples of such operations.
Painting and coating operations
Painting and coating operations require the use of solvents to thin paints or clean parts, or the use of paint containing solvents. But solvents emit VOCs. Sanding and grinding painted surfaces emit paint particles that mix with VOCs.
Welding and cutting.
Welding and cutting operations in automotive manufacturing produce fine metal particles that disperse into the air. During these operations, VOCs may be released from surface coatings or lubricants used on metal parts.
Metal machining operations
Operations on metal parts, such as grinding, sanding or turning, generatemetal particle emissions. What’s more, these operations often involve the use of lubricants or solvents, resulting in VOC emissions. Together, they can form a mixture of VOCs and metal dust in the air.
Component assembly
The assembly of metal or plastic components may involve the use of adhesives, lubricants or solvents that emit VOCs. In addition, assembly operations often involve drilling, grinding or polishing components, which can generate metal dust or plastic particles. The proximity or intermingling of these operations leads to an atmosphere laden with VOCs and dust.
Manufacture of plastic automotive parts
Plastic part manufacturing processes can generate VOCs from plastic resins, additives or release agents. In addition, finishing, cutting and sanding operations on plastic parts can also produce dust particles.
Odors emitted by VOCs and dust in the automotive industry.
The solvents and thinners used during painting and coating operations give off characteristic odors: sweet fruity (toluene, xylene), fruity and pungent (acetone, isopropyl alcohol, butyl alcohol), fruity and flowery (esters).
A burning or smoky odour may be produced if welding or cutting burns a surface coating or lubricant. In addition, various chemical odors can be generated by VOCs exhaled by paints, anti-corrosion coatings and lubricants when they heat up during these operations. Welding operations can also generate ozone, with its characteristic pungent odour, when using electric arc welders.
During machining operations on metal parts, friction between the tool and the metal sometimes leads to overheating, resulting in metallic or burnt smells. The lubricants used also emit distinct odours. They will be identified by the worker as greasy, petroleum or chemical, depending on the type of lubricant used.
The VOCs released by adhesives, lubricants and solvents during assembly operations give off a variety of chemical odors, such as sweet, pungent or earthy, depending on their composition. Additional drilling, grinding or polishing operations, if they heat up the materials, generate smoky or burnt odors. Thermal or chemical decomposition of materials during assembly operations produces specific odors linked to the by-products formed.
During the manufacture of plastic automotive parts, odor nuisance results from the combination of chemical odors from resins, solvents and additives. In addition, there are often dusty odors from surface finishing.
ATEX risk generated by dusts and VOCs in the automotive industry
VOCs and particulates emitted during painting and coating operations can generate ATEX. Possible sources of ignition include: sparks, e.g. when sanding or grinding painted surfaces, the presence of hot surfaces, electrical equipment that does not comply with ATEX standards, etc.
In welding and cutting operations, the VOCs released by the vaporization of surface coatings or by the projection of lubricant aerosols, and the dispersion of metal particles will contribute to the formation of an ATEX.
Operations on metal parts produce a combination of airborne metal particles and flammable VOCs, which will form an explosive mixture if concentrations of these substances reach explosive limits. They produce sparks or heat due to friction between the tool and the metal part. These sparks or heat can ignite mixtures of VOCs and metal dust, triggering an explosion.
During assembly operations, the VOCs emitted can form explosive mixtures with the air. Likewise, fine particles produced during drilling, grinding or polishing of components or other operations enter into suspension. They increase the ATEX risk by providing additional contact surfaces for combustion. ATEX hazards can result in fires or explosions.
In the manufacture of plastic automotive parts, the presence of VOCs and dust in suspension in the workshop creates an ATEX risk through the formation of an explosive gas mixture. The equipment and tools used during these operations can be a source of ignition, igniting the mixture.
What operations emit dust and VOCs in the woodworking industry?
In the woodworking industry, several processes may emit dust particles and volatile organic compounds (VOCs) simultaneously or in close succession, resulting in an ambient atmosphere containing both dust and VOCs. Here are a few examples of these operations.
Sawing and wood cutting
Sawing and wood-cutting operations disperse dust particles into the air. At the same time, VOCs can be released if the wood has been previously treated with chemicals or solvents.
Sanding and finishing
Wood sanding generates fine dust which is dispersed in the air. Finishing operations, such as applying varnish, lacquer or paint to wood, can emit VOCs from the solvents used in these finishing products.
Gluing and assembling wooden parts
These operations often use glues or adhesives containing solvents that emit VOCs. Dust particles can also be generated during these operations, especially if parts need to be adjusted or worked on during assembly.
Industrial wood drying
Drying lumber in kilns can release VOCs, especially if the lumber contains natural resins or moisture that causes them to evaporate. During the drying process, wood dust can also be released into the air.
Odor nuisance associated with dust and VOCs in the wood industry
Woody odors come from VOCs released by dust particles from sawing, sanding and wood assembly, or from moisture evaporation during the industrial drying process. These odors vary according to the species processed. Humans perceive them as natural, resinous, sweet and slightly smoky. However, if the wood is treated, the odour nuisance comes from the chemical odours released by the dust. They will be perceived as strong and unpleasant, depending on the chemical substance used.
Chemical odors emanate mainly from solvents used in the application of paints, varnishes, finishing lacquers, glues or assembly adhesives, and persist during drying. Some of the odors released are unpleasant because they are perceived as pungent, pungent, chemical, medicinal, astringent, alcoholic… Olfactory nuisance varies according to the concentration of VOCs in the air.
ATEX risk associated with dusts and VOCs in the wood industry
The airborne combination of wood dust and VOCs from the chemicals used in the various woodworking operations creates a potentially explosive environment. The flammable mixture may encounter several ignition sources during woodworking. Operations involving friction between the wood material and a tool can generate heat. Tools and electrical equipment can emit sparks. The ATEX risk arises from the possibility of explosions or fires when mixtures of dust and VOCs are ignited by a source of ignition.
Dust and VOC emissions in the plastics industry. Odor nuisance and ATEX risk generated.
What operations emit VOCs and dust in the plastics industry?
Here are a few examples of operations that can emit dust particles and volatile organic compounds (VOCs) simultaneously, or within minutes of each other. When no preventive measures are taken, they lead to an atmosphere combining VOCs and dust.
Injection molding
The main polymers using this process are polyolefins (PE and PP), polyamides (PA) and polyethylene terephthalate (PET). The operation involves heating plastic resins, which releases VOCs. Similarly, additives and release agents can release VOCs when heated. Cutting or finishing operations on molded parts can generate plastic dust particles.
Plastic extrusion
Extrusion involves heating and shaping plastic resins to transform them into films, tubes or other shapes. Extrusion uses polymers such as polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polystyrene (PS), etc. VOC emissions come from heated resin or additives. Cutting operations on extruded products can generate dust.
Thermoforming
Thermoforming involves heating a sheet of plastic to make it flexible, then molding it into the desired shape. The most commonly used polymers are polystyrene (PS), polyethylene (PE), polypropylene (PP), polycarbonate (PC), acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC), polymethyl methacrylate (PMMA) and impact polystyrene (SB). VOCs are often dissipated during heating of the plastic, particularly if the plate contains additives. Cutting or finishing thermoformed products can produce plastic dust particles.
Cutting and polishing
When cutting or polishing plastic parts, contact between the tool and the plastic material disperses fine dust particles. If plastic parts have been treated with solvents or adhesives, VOCs will be emitted during these operations.
Surface treatment
Surface treatment operations, such as theapplication of paints, varnishes or coatings to plastic parts, release VOCs from the solvents used or contained in the products. Sanding or surface preparation prior to treatment releases dust particles into the air.
Assembly and gluing
Plastic parts assembly operations use glues or adhesives with potential VOC release. Cutting and preparation operations during assembly can generate plastic dust particles.
3D printing using plastics
The 3D printing of industrial parts, models and prototypes, or other products, using Acrylonitrile Butadiene Styrene (ABS) emits aerosols containing Volatile Organic Compounds (VOCs). These include nitriles (acrylonitrile, etc.), aliphatic hydrocarbons (butadiene, etc.), aromatic hydrocarbons (styrene, etc.) and aldehydes (formaldehyde, etc.). Deburring and sanding operations to finish printed parts emit dust.
Odour nuisance linked to VOC and dust emissions in the plastics industry
During injection molding, extrusion and thermoforming operations, odors come from VOCs emitted by the heating of plastic resins, additives (stabilizers, plasticizers, antioxidants) and release agents. Odors are generally characterized as plastic, chemical or solvent. Some odors can be stronger and more pronounced, especially when temperatures are high.
In addition, odors associated with the application of paints, varnishes or coatings to plastic parts, or with assembly operations using glues and adhesives, derive mainly from the VOC solvents present in their formulation. They are often described as strong, pungent or chemical, depending on the solvents used.
Similarly, VOC odors during cutting and polishing originate from the chemicals, such as solvents, glues, etc., used during pre-treatment. These odors vary according to the substances present. In 3D printing, the decomposition of the material and the additives it contains releases various VOCs, resulting in a variety of odors ranging from pungent, pungent and irritating to sweet, sweet and aromatic.
Although dust particles themselves have little odour, they can carry VOCs from the air. In addition, the fine particles generated by the cutting operations may have been calcined or heated during the process. They then contribute to the diffusion of odors described as “burnt plastic” or sometimes “chemical”. Odors associated with dust can also come from surface preparation and treatment products impregnated into the plastic.
ATEX risk linked to the release of VOCs and dust in the plastics industry
The mechanisms that cause an explosive atmosphere are :
- the emission of flammable VOCs either during the heating of resins and additives, or by solvents contained in the various treatment products;
- the generation of fine dust during cutting or finishing operations, sanding or surface preparation.
Secondly, the concentration of VOCs and particles in the air can create an explosive atmosphere. Some operations can generate heat or sparks, particularly through friction or electrical contact. These ignition sources can ignite VOCs or dust particles suspended in the air, causing an explosion.
Dust and VOCs emitted in the paint and coatings industry. Odors and induced ATEX risks.
What operations emit VOCs and dust in the paint and coatings industry?
Here are a few examples of operations
Paint and coatings manufacturing
In the manufacture of paints and coatings, the mixing and grinding of pigments and resins can generate dust particles. The solvents used in paint formulations can emit VOCs during the mixing process.
Preparing the surface to be painted
Sandblasting or shotblasting operations to prepare a surface produce dust. Solvents used to clean or degrease surfaces before applying paint can emit VOCs.
Paint and coating application
Paint and coating application operations, notably by spraying (liquid or electrostatic powder), can emit paint aerosols as well as VOCs from the solvents used in the paints. Drying operations after paint application can also release VOCs as solvents evaporate.
Sanding and polishing
Sanding or polishing painted or coated surfaces generates dust. These operations are carried out after paint or coatings have been applied, and result in the dispersion of VOC-containing dust in the air.
Recycling and waste treatment
Recycling or processing paint waste can release dust particles. Residual solvents or chemicals may release VOCs during these operations.
Odour nuisance linked to VOC and dust emissions in the coatings industry
Odors are mainly due to the VOCs present in the solvents used in paint formulation, surface preparation and paint thinning prior to application. These solvents emit aliphatic or aromatic hydrocarbon VOCs, alcohols, esters and other volatile organic compounds. The odors are often strong. Some can be described as chemical, acrid or pungent, others as sweet. Specific odors depend on the solvents used in the paint formulation.
Pigment and resin mixing and grinding operations release dust particles into the air, which can give off characteristic odors depending on the composition of the material used. Some are milder or neutral scents, while others are more resinous or mineral.
Paint particles sprayed during application also release odours via VOCs. Drying and drying coatings also release VOCs, and hence odors. The same applies to the suspension of VOC-containing paint dust during sanding and polishing operations.
ATEX risk linked to the release of VOCs and dust in the coatings industry
Solvents used in paint formulations release VOCs during mixing, application, drying, etc. These VOCs will form an explosive atmosphere when mixed with air in the right concentrations.
The mixing and grinding of pigments and resins, surface preparation, sanding and polishing operations, etc. disperse fine dust particles into the air, creating a potentially explosive atmosphere.
The mixing of VOCs and dust creates an ATEX risk. Sources of ignition such as electrostatic discharge, heating, etc. may emerge during operation. The result will be fire or explosion.
What operations emit dust and VOCs in the food industry?
Here are a few examples of activities that emit VOCs and particles in a food processing plant.
Receiving, handling and storing agricultural raw materials
The movement of certain raw materials, such as cereals or spices, spreads dust. Raw materials treated with chemicals (e.g. stock protection pesticides, preservatives) will emit VOCs during handling.
Grinding and milling of agricultural raw materials
These operations on grain, cereals or other raw materials disperse organic dust. If the raw materials contain chemical treatment or preservative agents, VOCs will be emitted.
Cooking and heat treatment of food
These operations release VOCs from heated ingredients (e.g. oils, spices) or additives used in formulations. Grinding or mixing operations after firing can generate dust particles.
Food packaging and conditioning
These operations release particles into the air from thepackaging or from the food products themselves. VOC emissions come from the adhesives, printing inks and chemicals (preservatives, antimicrobials) used in these operations.
Cleaning and disinfection
These operations use chemicals that often release VOCs. In addition, the cleaning of food residues can generate fine particles.
Odor nuisance from VOCs and dust in the food industry.
Agricultural raw materials treated with pesticides or preservatives will emit odors due to the release of VOCs.
Odors from thesecompounds can be pungent, chemical or unpleasant. Similarly, agricultural raw materials will give off unpleasant odors of fermentation or decomposition if stored for long periods or in unsuitable conditions. Certain VOCs, by-products of the thermal decomposition of foodstuffs and additives (artificial flavourings, preservatives during cooking), can emit cooking odours considered unpleasant by workers. Lastly, VOCs from adhesives, printing inks and chemicals can emit strong, pungent chemical odors during packaging operations.
Dust from the transfer of raw materials treated with pesticides or preservatives can give off a chemical or pungent odor. Grinding or milling operations can accentuate this phenomenon. Dust particles dispersed during the handling of packaging materials or food products produce an odorous mixture that can be considered unpleasant by employees.
The ATEX risk posed by VOCs and dusts in the food industry
Food raw materials are handled or stored in bulk. Transfer takes place in large masses and suspends combustible fine dust. The ATEX risk arises from the movement of these large masses, which produces electrostatic discharges that ignite the dust cloud. Pesticides and preservatives used on these products emit often flammable VOCs. This increases the ATEX risk.
In the same vein, dry grain grinding and milling operations disperse fine, dry dusts that are highly flammable. VOCs from preservatives release equally flammable VOCs that contribute to an explosive atmosphere.
The same applies to cooking VOCs, which, if present in sufficient concentration in the air, will form an explosive atmosphere. The fineness of the particles emitted by grinding or mixing after firing also creates a risk of explosion. All of which accentuates the ATEX risk.
Dust particles dispersed in the air from food products or packaging materials, and VOCs emitted by adhesives, inks and other chemicals also contribute to an explosive atmosphere. If the concentration of organic dust or VOCs reaches a certain flammable threshold, the ATEX risk is confirmed. Wrapping and packaging operations use electrical machines or equipment, and friction between materials can be a source of ignition.