Modern chemical technology is associated with grinding, crushing, transportation of various materials. Some of them turn into an aerosol form during processing, the resulting dust, together with ventilation and process gases, enters the atmosphere. Consider the basics of chemical technology currently used in production.
Dust cleaning apparatus for gaseous substances
Dust particles have a high total surface, as a result they exhibit increased biological and chemical activity. Some substances that are in an aerodispersed form have new properties, for example, they are able to spontaneously explode. There are various chemical technology devices used to purify gaseous substances formed in production from dust particles of various sizes and shapes.
Despite significant differences in design, the principle of their operation is based on the delay of the weighted phase.
Cyclone and settling chambers
Analyzing various processes and devices of chemical technology, let's focus on the groupdust collectors, which include:
- rotary dust collectors;
- cyclones;
- shutter models;
- dust collection chambers.
Among the advantages of such devices, we note the simplicity of their design, due to which they are produced at non-specialized enterprises.
As a minus of such devices, professionals note the lack of efficiency, the need for re-cleaning. All types of dust collectors operate on the basis of centrifugal forces, differ in power and speed of deposition of dust particles.
For example, the classical chemical technology for the production of sulfuric acid involves the use of a cyclone to remove impurities from the furnace gas formed during the roasting of pyrite. The gas, in which there are particles of cinder (mixed iron oxide), enters the cyclone through a special tangential nozzle, then rotates along the inner walls of the apparatus. Accumulation and sedimentation of dust is carried out in the dust bin, and the purified gas rises up, goes to the next apparatus through the central pipe.
Chemical technology is associated with the use of a cyclone in cases where high requirements are not put forward for the resulting gaseous substance.
Wet cleaning machines
The wet method in modern production is considered one of the most effective and simple types of purification of industrial gases from a variety of suspended particles. Processes and devices of chemical technology related towet cleaning of gases, are currently in demand not only in domestic, but also in foreign industry. In addition to suspended particles, they are able to capture gaseous and vaporous components that reduce the quality of products.
There is a division of such devices into packed hollow, foam and bubbling, turbulent and centrifugal types.
The disintegrator consists of a rotor and a stator equipped with special guide vanes. Liquid is fed into the rotating rotor through nozzles. Due to the gas flow moving between the stator and rotor rings, it is crushed into separate drops, as a result of which the contact of gases with the trapped particles of liquid increases. Due to centrifugal forces, dust is thrown to the walls of the apparatus, then removed from it, and the purified gaseous substances enter the next apparatus, or are released into the atmosphere.
Porous filters
Often chemical technology involves the filtration of substances through special porous partitions. This method involves a high degree of purification from a variety of suspended particles, so porous filters are in demand in the chemical industry.
Their main disadvantages are the need for systematic replacement of filter components, as well as the large dimensions of the devices.
Industrial filters are divided into granular and fabric classes. They are designed to purify industrial gaseous substances with highthe concentration of the dispersed phase. To carry out periodic removal of accumulated particles, special regenerating devices are installed in the apparatus.
Features of oil refining
Fine chemical technologies associated with the purification of oil products from mechanical impurities and high humidity are based precisely on filtration processes.
Among those processes and devices that are currently used in the petrochemical industry, there are filtration through coalescing partitions, ultrasound. With the help of centrifugal separators, coalescent filters, settling systems, a preliminary purification stage is carried out.
In order to carry out complex purification of petroleum products, porous polymer compositions are currently used as a filter material.
They have proven their effectiveness, strength, reliability, so they are increasingly used in general chemical technology.
Electric filters
Chemical processes in sulfuric acid production technology require the use of this particular apparatus. The cleaning efficiency in them is from 90 to 99.9 percent. Electrostatic precipitators are capable of capturing liquid and solid particles of various sizes, devices operate in the temperature range of 400-5000 degrees Celsius.
Due to their low operating costs, these devices have become widely used in modern chemical industry.production. Among the main disadvantages of such equipment, we highlight the significant initial costs for their construction, as well as the need to allocate a large space for installation.
From an economic point of view, it is advisable to use them when cleaning significant volumes, otherwise the use of electrostatic precipitators will be a costly undertaking.
Contact machine
Chemistry and chemical technology involves the use of a variety of apparatus and devices. Such an invention as a contact apparatus is intended for the implementation of catalytic processes. An example is the oxidation reaction of sulfur oxide (4) to sulfur dioxide, which is one of the stages in the technological production of sulfuric acid.
Thanks to the radial-spiral year, the gas passes through a layer with a catalyst located on special baffles. Thanks to the contact apparatus, the efficiency of catalytic oxidation is significantly increased, and maintenance of the device is simplified.
A special removable basket with a protective layer of the catalyst makes it easy to replace it.
Kiln
This apparatus is used in the production of sulfuric acid from iron pyrites. The chemical reaction takes place at a temperature of 700 °C. Thanks to the principle of countercurrent, which involves the supply of air oxygen and iron pyrite in opposite directions, a so-called fluidized bed is formed. The point is that the particlesminerals are distributed evenly over the volume of oxygen, which guarantees a high-quality passage of the oxidation process.
After the completion of the oxidation process, the resulting "cinder" (iron oxide) enters a special hopper, from which it is periodically removed. The resulting furnace gas (sulfur oxide 4) is sent for dedusting and then dried.
Modern kilns used in chemical production can significantly reduce the loss of reaction products while increasing the quality of the resulting furnace gas.
In order to speed up the process of pyrite oxidation in the kiln, in the production of sulfuric acid, the feedstock is pre-crushed.
Shaft ovens
These reactors include blast furnaces, which form the basis of ferrous metallurgy. The mixture enters the furnace, contacts with oxygen supplied through special holes, and then the resulting cast iron is cooled.
Various modifications of such devices have found their application in the processing of not only iron, but also copper ores, and the processing of calcium compounds.
Conclusion
It is difficult to imagine a full-fledged life of a modern person without using a product of chemical production. The chemical industry, in turn, cannot fully operate without the use of automated and mechanical technologies, the use of special equipment. Currently, chemical production is a complex set of equipment and machines that are designed for chemical-physical and chemicalprocesses, automated equipment for packaging and transportation of finished products.
Among the main machines and devices in demand in such production, there are those that allow you to increase the working surface of the process, carry out high-quality filtration, full heat exchange, increase the yield of reaction products, and reduce energy costs.
