A valuable resource is water. All wastewater is therefore first purified of containments and pollutants before it is returned to the water cycle in order to save our natural waters and promote the production of drinking water. Different techniques are applied to the water to treat it and produce the highest, most natural water quality. To learn more about wastewater treatment be sure to check out Cleanawater.
In general, there are two different basic types of wastewater treatment. First, harmful elements are taken out of the water. This is accomplished through cleaning, desalination, sterilization, removal of iron, manganese, or softening. Second, particular supplements are added to boost quality and have an impact on variables like pH or conductivity.
Municipal wastewater treatment facilities must treat the most wastewater, so a more varied combination and more efficient process are required here. Depending on the kind of wastewater treatment plant, several processes are used. There are various steps to the treatment procedures in wastewater treatment plants.
Step 1: Mechanical water treatment
The first stage of wastewater treatment involves mechanically treating the remaining entirely untreated wastewater, which eliminates 20–30% of the contained particles. In a screening facility, where a screen or sieve drum filters out coarse pollutants like leaves, paper, or textiles, wastewater is directed to do this.
The coarse materials are gradually filtered out by a variety of screens, ranging from coarse screens with a gap width of several centimeters to fine screens with a gap width of a few millimeters, through which the water travels at various speeds. The screen material that was mechanically retrieved is dewatered and disposed of in an incinerator facility.
The introduction of process air causes a rolling motion in the water, which lifts lighter particles, such oils and fats, to the surface, allowing the aerated sand collector to remove additional fats and oils from the wastewater. Here, it is simple to get them out of the water.
Step 2: Biological water treatment
The pre-purified water from the mechanical treatment stage now enters what are known as aeration tanks, which are frequently created as circulation tanks, in the majority of wastewater treatment plants. The biological cleaning process happens here.
Propellers and the addition of oxygen are used to circulate the water. Different milieu conditions are established for bacteria and germs in more or less ventilated locations. These microbes consume the remaining organic pollutants in the water and transform them into inorganic materials. The availability of oxygen encourages bacterial growth, which aids in the production of activated sludge.As a result, the activated sludge process is another name for this biological wastewater treatment procedure.
Step 3: Chemical water treatment
Chemical methods are employed in the wastewater treatment process at this step. In order to attain the statutory water standard levels, chemical substances are used. A few of the chemical processes used in wastewater treatment facilities are neutralization, disinfection, phosphate precipitation, nitrogen removal, deicing, and manganese removal.
With the addition of an acid, neutralization is utilizedto create the desired pH level. The addition of chlorine or chlorine dioxide during disinfection kills microorganisms. An excellent substitute for adding chemicals to wastewater is to irradiate it with UV light; however, this method is not as widely employed. They cause nutrient enrichment and over fertilization of water bodies if they are allowed to remain in the wastewater, which can result in eutrophication, or the growth of plants that are not necessary and are therefore bad for the ecosystem.
