Modern sewage treatment: features, description and types
The process of urbanization and in particular the expansionutilities complicates the tasks of serving urban organizations. The fight against sewage pollution in this respect is particularly important, since waste products of household fluids have a direct impact on the hydrological system of the terrain. In connection with this, more effective means of minimizing negative environmental impact processes are being developed. Today, wastewater treatment is organized taking into account several factors for eliminating harmful microorganisms. The main way of water purification is still the arrangement of mechanical filtering stations, but even more often there are complex installations that perform high-quality biological water treatment.
Features of modern wastewater treatment
Engineering equipment is developed by commondirections that are oriented towards increasing ergonomics and reliability. Therefore, the modern sewage treatment plant is multifunctional, efficient and easy to manage. Both industrial and domestic drainage filtration systems are equipped with control panels with a wide range of settings.
In addition, project developerssewer and septic systems are trying to maximize the rationalization of communication networks, optimizing energy resources. In other words, sewage treatment at some sites can also be combined with integrated engineering systems at home or enterprise. And this is not speaking about increasing the basic operational capabilities of the cleaning equipment, which is achieved through the use of high-tech filtration materials.
The whole process of wastewater treatment is divided intoseveral stages that have significant technological differences. The stage of mechanical filtration is primary and at the same time multi-stage. The simplest mechanism of such cleaning can be observed on the streets in the form of metal, concrete or plastic gratings, which detain debris, foliage, stones and other large elements. In the future, effluents can be sent through the canal to special centrifuges and hydrocyclones. Also, to detain microscopic particles, a special filter is used - in effect, it is a filtration cleaning station. Due to such equipment, the drain can be cleaned of elements up to 0.25 mm. Together, the cleaning steps by this point make it possible to eliminate about 80% of foreign bodies in the waste fluid.
Means of this kind of purification are usually usedas a continuation of mechanical filtration. It can be said that basic purification by the percolators prepares liquid for deeper processing by biological stations. At the same time, both methods work according to different principles. That is, it is wrong to assume that mechanical filtration detains large particles, and biological installations are small. The second option focuses on the ecological neutralization of water, which does not cause chemical damage during the maintenance and after release into water. To date, the biological purification of effluents primarily aims at eliminating organic matter or its processing. As a result, the composition of the liquid medium retains only dissolved nitrates and oxygen. In practice, such purification is realized in two ways - natural or artificial. In the first case, waste water is dispersed in filtration fields and in biological ponds. Artificial cleaning is carried out in special aerotanks, which release environmentally safe water into water bodies.
Chemical and thermal cleaning methods
From the point of view of elimination of negative processesdecomposition in the waste environment one of the most effective methods is chemical reagent. As a rule, this group of methods is based on oxidation-reduction reactions, which in effect abolish certain reactions, replacing them with other, environmentally less dangerous ones. But the most effective method of controlling pollution in wastewater is thermal exposure. This method is carried out with the help of furnace installations and burners, in which the liquid is burned. It is also practiced and cleaning of sewage by the fire method without the use of furnace facilities. Technologically, this method involves spraying the liquid in a finely dispersed state into a special torch formed by burning gaseous fuel. As a result, water evaporates, and harmful compounds are eliminated.
New technologies, thanks to whichcomplete elimination of the decomposition products is provided, while they are not used at all treatment facilities. Moreover, this principle does not always justify itself economically. Therefore, traditional cleaning channels are still common, the work of which leaves precipitation. The new technologies in such processing processes manifest themselves at the final stage of utilization of the residues. In particular, methane tanks are used. These are massive ferro-concrete tanks, in which biogas is formed by fermentation. As a result, methane fuel is formed, which can later be used in boiler rooms instead of traditional fuel. Also, complex treatment of sewage with the elimination of sludge involves the use of methods of mechanical dewatering with the use of special apparatus - centrifuges, belt or chamber press units. In the future, the products of such processing, depending on the chemical composition, can be used in agriculture as fertilizer.
At this stage of development of sewer systemsMany manufacturers solve the problem of a complete transition to one of the cleaning methods. This is due to the fact that the technical organization of several stages of processing contaminated liquid is expensive and requires the connection of large resources in the process of maintenance. Alternatively, a biological wastewater treatment plant is considered, which also provides for mechanical processing functions, but only as ancillary steps. However, this option can not be called universal, since biological aerotankers lose by the effectiveness of eliminating harmful particles with the same thermal treatment. Therefore, it is still advisable to approach the problem of wastewater treatment by developing projects that take into account the individual conditions and requirements of the treatment equipment operation.