Wastewater treatment is carried out with the purpose of liquidation of contra-indicated elements from the fulfilled waters for the further their draining in the rivers, lakes, on a ground or secondary use. Wastewater can include rainstorms, waste resources, precipitation from the atmosphere (rain, thawed snow). The negative impact of polluted water resources affects the environment and society, so the importance of wastewater treatment is difficult to underestimate. Such water must be cleaned in order to comply with the regulations.
 

Waste water and pollution control

 
To stabilize the natural balance and save water, several filtration methods are used to purify the pollutants.
 
The main types of sewage treatment are:
Mechanical action based on filtration or sedimentation of large dispersed contaminants. The choice of cleaning equipment depends on the degree of concentration of harmful substances. Applying this method for sewage flushing, cleaning is 70% and up to 90% cleaning the sewage industry.
Purification of pollution by chemicals is carried out with the help of toxic elements, which destroy difficult dissolving substances, forming a sediment in the tanks.
Methods of physico-chemical effects are designed to eliminate poisonous compounds from water drains.
Filters, reservoirs and ponds of biological purpose, are the basis of biological purification methods.
Removal of malicious elements can also be done in a complex manner using all of the above methods.
Using cleaning equipment for such structures, it is necessary to adhere to the established sanitary standards. Sanitary control and the correctness of the use of cleaning methods at private and public facilities are carried out by the owner independently, in multi-storey houses, a water canal. Modern cleaning systems allow to remove contamination of sewage for secondary use for industrial or household purposes. The quality of the cleaning depends on the number of harmful elements (components) that have been eliminated from contaminated sewage and the compliance of these wastewater with the established standards. The determination of the necessary treatment equipment depends on the required result and on the initial data on the contamination.
 

Location of treatment equipment

 
The equipment is installed one after another in such a sequence that the contaminated water masses passing through it are cleaned evenly and sequentially. Initially, the liquid is subjected to mechanical action, where it is settled and the separation of large contaminated substances takes place. After it is purified by a biochemical method, separating less significant substances. The final procedure is water disinfection.
 
Cleaning of sewage systems requires the installation of linear cleaning facilities. After the stage-by-stage elimination of pollution, water can be reused or taken to rivers, lakes, and soil. The resulting sediment can be used in agriculture.
 
Scheme of waste treatment:
  • Automatic processes with the use of sanding and gratings, detaining clogging stones, leaves, paper and so on;
  • Sludge tanks for large-dispersed waste. There is a separation of impurities with a greater density than water itself. At this stage, chemical methods can be used.
  • Methane tank for methane collection, gas outlets, automatic sedimentation and separation, hydraulic conveyors with pumps.
  • Biological filters;
  • Aerotank;
  • Disinfection.
 
Cleaning from sewage according to the methods of classification, preceded by a preliminary cleaning, which implies:
  • Control of uniformity of stock masses;
  • The use of settling tanks, sanding, grating equipment, pressure hydrocyclones, equipment for the separation of oil products, erkensators;
  • coagulation electrical, flocculation;
  • regulation of subacidity;
  • disinfection.
 
Secondary wastewater treatment may consist of:
Adsorption, evacuation. Elimination of molecular phlegmatizers.
Weakening of electrovalent mixtures.
Repeated decontamination to completely eliminate the pathogenic microbes and additives that appeared at the preliminary cleaning levels.
Destruction of organic additives by biological methods.
WWTP
 
To maintain a stable standard of living of mankind, purifying mechanisms of local character are used, which are complex constructions of sewerage systems. The sewage treatment facilities are installed taking into account the volume of the tanks for the stable implementation of all required processes. According to statistics, one person per day uses about 200 liters of water and the amount of stock equipment should be the same.
 
Important! Local cleaning facilities (VOCs) are designed to clean sewage drains of personal possessions or a slightly populated territory when there is no possibility of joining the drainage systems of central importance.

 

In such areas, cleaning systems are mounted independently.

 
A plastic container for settling the effluents in the required quantity. The capacity is divided into sections, where the stage-by-stage wastewater treatment is carried out. This capacity has a long service life and does not require significant effort to maintain it.
For significant industrial enterprises and cities, aerotanks are used. Large tanks, working on the principle of mixing with a sludge of high activity of sewage, through the introduction of oxygen. The composition of the aeration tanks includes catchers for the separation of petroleum products and fatty impurities. Such systems, when used privately, are small in size and are part of septic tanks or other local cleaning lines that include them.
Biological filters are rarely used autonomously. Often used as part of VOCs.
 The waste water streams entering the VOC undergo such purification steps:
 
Tank sediment by mechanical principle;
Bio-elimination of contamination with the use of colonies of protozoa;
Additional cleaning.
Industrial waste water treatment plant
 
Carrying out purification procedures in industrial enterprises, it is necessary to adhere to the established norms of sanitation. Sanitary norms are always taken into account at the initial stages of project development. To connect the withdrawal of pollution of enterprises to the central drain systems, the norms for the content of harmful substances in the liquid are established:
 
The biochemical indicator of the oxygen consumption of the treatment plants should not exceed the value established in the sewage system;
It is forbidden to combine cleaning mechanisms of enterprises, interfering with the normal operation of drainage systems;
The values ​​of the water hardness index should be 6.5-9, and the temperature regime should be maintained to 40 degrees;
It is unacceptable to clog the sewerage wells and the pipeline with uncleaned waste;
Sewage should not contain substances that adversely affect the condition of the drainage mechanisms;
It is not allowed to withdraw if there are viruses, radioactive, highly pathogenic or explosive substances in the sewage;
The composition of the withdrawn liquids should not include surface-active, rigid elements.
The value of chemical use of oxygen should not exceed the biochemical index by 2.5 times.
In case of deviation of industrial effluents from an established standard, the enterprise is obliged to carry out preliminary cleaning works on the adjacent zone independently. The rules are regulated by local authorities and commissions that design city drainage structures.
 
Industrial wastewater treatment for production uses methods:
  • Change in the chemical content of contaminated water.
  • Biochemical treatment.
  • Sewer cleaning methods
 
In our time, the treatment of sewage sludge is very important. The current contaminated domestic waters contain many caustic elements and impurities, which negatively affects the ecological situation. They must also be processed.
 
If you ignore the treatment procedures, all rivers and lakes in a short period of time will become garbage dumps. The aggregate in the drains of harmful elements (viral, pathogenic, chemical and other) is large.
 
Centralized sewerage systems for the disposal of contaminated water are constructed on the principle of treating effluents in three ways.
 
  1. Automatic removal of contaminated masses before entering the sewage system in order to get rid of significant insoluble blockages. In the municipal sewerage system, various wastes (rags, stones, animal remains, etc.) come in, which requires filtration. After that there is a sediment of a liquid with the subsequent passage through filters of a sandy and gravel kind. Carrying out this method, chemical, viral substances and microbes remain in the effluent. When using automatic cleaning mechanisms, large areas of size are required to fully equip the relevant equipment, and the installation is carried out in a complex manner with other systems.
  2. Chemical methods are used rarely and only for industrial wastewater. The system uses organic and chemical elements. As a consequence of their work - a sediment. Because of the high cost and significant time costs, it is not used as an additional cleaning for the removal of sewage sludge. Large industrial plants use this technology to remove chemicals from water.
  3. Cleansing by biological methods is now more in demand. Inhabit bacteria that feed on waste of life - this method is effective. Widely used for cleaning autonomous systems and lines of centralized sewerage. The application of this method helps to eliminate harmful elements by 90% and allows the use of purified water for a secondary economic purpose or pour it into water bodies.
  4. Elimination of pollution by anaerobic organisms that do not require oxygen saturation. The application of anaerobes is effective by 95%. Silt deposits necessarily occur in the bottom of the tanks due to the action of microorganisms. Silt can be used as fertilizer.

Structure of technological purification:
  • Sandpipers, lattice equipment, settling tanks;
  • Aerotanks;
  • Systems of water disinfection.
 

Sediment processing

After passing the stage-by-stage purification procedures through biological and mechanical devices, the initial sedimentary particles are formed, which require further transformation to reduce the hazard.
 
The transformation process is based on the processes of sludge and fermentation followed by dehydration and drying. After the removal of chemical poisons, the sediment can be used for other purposes.
 
Transformation is carried out in methantants, biological filters, septic tanks.
 

Varieties of cleaning structures

 
The structure of the wastewater treatment processes requires the installation of such equipment:
 
  • Primary systems for filtration of large clogs, processing of sediment in the form of methane tents with settling tanks in two tiers with area for silt;
  • Biological filters;
  • Disinfection mechanisms.
 
Types of buildings cleansing:
 
  • A typical variety of buildings designed to clean city drain sewers;
  • Purification lines for enterprises;
  • Independent designs for eliminating pollution for small settlements and private property;
  • Sewage system for storm sewage.
 
Purification lines for enterprises are complex designs. The effluents of industrial production are cleared of a huge number of harmful mixtures and additives of poison. At the same time, specialized equipment is used. Sewer lines of central destination are connected to different systems, including industrial ones.
 
In their own homes are used individual sewage mechanisms that allow the use of water several times. It is not advisable to use garbage as a sewage system, which can lead to contamination of land and drinking water nearby.
 
Water resources are not infinite and reasonable use of them can save such a valuable resource for future generations.