In foundries the sprinkler systems are used for the removal of wet dust and odors. Nebulizers have advantages and disadvantages compared to other systems for dust filtration and removal. In this article we identify and analyze our technologies used to reduce the risks arising from dust within the plant, and reduce the complaints that may arise from the presence of dust and odors that spread outwards of establishment.
Used in foundries, wet scrubber technology, made with MGF nebulizers, it is ideal to intercept hot and humid dust and suppress it, for example during preparation, transportation, shakeout and molding recovery. In these phases, dry technology, through filter is not suitable. In fact:
- residual moisture present in the dusts would clog the filter and pipes, making it particularly onerous maintenance of the plant.
- the powders heat makes them particularly volatile and thus more difficult to intercept through a suction system: nebulization in this case provides a double effect, making dust particles heavier and cooling air that carries them, consequently the particles tend to precipitate more quickly to the ground.
- last but not least, nebulization is much more effective with fine dust, as the filtering system generated by the fog is random and is regenerated continuously.
The negative aspects of this technology are the formation of more or less dried sludge that must be disposed.
Volatile organic solvents removal
The nebulization of acid solutions can be suitably used for the abatement, as well as dust, also of volatile organic solvents, due to the chemical reaction that develops. Typically the acid solution in this case is maintained at a pH between 2 and 4 by the addition of sulfuric acid, H3PO4.
This process takes place on the suction line of the mould blowing machine and the solution is sprayed inside the suction duct, as if it were humidifying. The solution is then recovered and is reintegrated sulfuric acid if necessary.
Also in this case it is necessary to eliminate the sludge resulting, by a device sludge dredger in action inside the duct.
A wet scrubbers alternative
The principle of operation of the misting as dust suppression system is similar to the wet scrubber, with the difference that the scrubber works at lower pressures on average due to the fact that the dedusting takes place in a confined environment and there are demisters and structural fills.
When for cost and plant reasons you can not use scrubbers, for example, if the environment is so great as to make ineffective a fume hood (and the following scrubber), then a misting tent performs exactly the same function, without the creation of a vacuum system.
The same technology is used in spray scrubbers and wet scrubbers.
Foundries bad smell reduction
Another application in the foundries is the reduction of odor resulting from the casting of cast iron, steel and light alloys. In fact, unlike the dry abatement systems, it is possible to filter the smallest particles of dust, but also dissolve in solution all the pollutants generated by the process and reduce odors generated by them.
It’s also possible to dose in the fog chemicals reactants with pollutants to increase the effectiveness of odors reduction.
Our technical department is available to create specific chemicals for the abatement of smoke odor with a specific chemical composition.
Hereafter the features of the product that is typically used to reduce smells in foundries:
- specially formulated to neutralize the odorous molecules that cause bad smells. Unlike normal products on the market, does not cover the odors but eliminates them to the base through a mechanism of ionic exchange. Olfactometric surveys conducted according to UNI EN 13725 have shown efficiency in terms of odor abatement up to 70-80%.
- formula based on essential oils, with technological additives in aqueous medium. Completely biodegradable.
- surfactants present in it does not contain phosphates and are therefore not classified as dangerous according to Directives Applicable Law relating to the classification, packaging and labeling of dangerous preparations.
- has no toxicity to humans and is not in any way dangerous to aquatic organisms. It is not subject to any phrase R51, R52 or R53 unlike many products that smell like environments.
- Is supplied in concentrated form but is easily soluble in water according to the recommended dosage. It should be diluted in water as a function of smell intensity from breaking down in proportion to the place where act and system used. Generally we recommend a dilution of the product in a range that varies between 0, 5 and 2% (between 0.5 kg and 2 kg in 100 liters of water). Obtained by spraying a very specific equipment, facilitates action of the product by accelerating the removal of malodorous molecules and optimizing consumption.
- National Institute For Occupational Safety And Health (NIOSH-USA): Registry of Toxic Effects of Chemical Substances, 2003.
- Environmental Protection Agency (USA): Integrated Risk Information System (IRIS).
- American Conference of Governmental Industrial Hygienists (ACGIH-USA).