Waste water treatment is the process of removing contaminated substances from water and converting it into effluent that will not harm the environment and maintain the purity of water bodies. Waste water discharged from factories and laboratories is a pressing matter, it essentially impacts the bodies of water like rivers, ponds, lakes and makes them polluted and unfit for drinking and aquatic animals suffer on it’s account too. Treatment may consist of chemical, biological, or physical processes or a combination thereof. Water may be treated to any level of quality desired. Waste water consists of many pollutants like bacteria, chemicals and other toxic substances. There are two wastewater treatment plants namely chemical or physical treatment plants, and biological wastewater treatment plants.
Biological wastewater treatment uses biological substances like bacteria (aerobically or anaerobically), algae, and fungi (aerobically) and breaks down the waste matter into simpler substances. Physical waste treatment plants use chemical reactions as well as physical processes to treat wastewater.
Biological treatment is ideal for waste discharged from households and business offices. Physical treatment is more suitable for the large amount of waste water discharged by manufacturing units, factories, mills etc.
Wastewater treatment process is a multi tiered procedure which consists of primary, secondary and tertiary stages.
First level eliminates the waste through the use of screens and settling tanks. At this stage, the essentially large impurities like sticks, big stones and other miscellaneous wastes are removed from the water being treated.
Second level makes the use of bacteria and oxygen to engulf the remaining pollutants and further increase the level of purity obtained for distribution to lakes,rivers, households etc.Tertiary (or advanced) treatment removes dissolved substances, such as colour, metals, organic chemicals and nutrients like phosphorus and nitrogen. There are a number of physical, chemical and biological treatment processes that are used for tertiary treatment. One of the biological treatment processes is called Biological Nutrient Removal (BNR).
Environment can only be restored to its former integrity and purity if we pledge to eradicate the problems from the roots. The harmful impact waste water poses for us is that it is gradually rendering the water level unfit for drinking and poses a threat to aquatic life forms. We are polluting the water resources which is an essential component we need for survival on the planet and it is gradually decreasing the amount of water available for our use. The impact on wildlife and their habitat these chemical discharges pose are unprecedented and treacherous.
Another harmful effect of this chemical laden water is squalor. It strips the environment of it’s beauty and hygiene and makes it smelly and undesirable to go about. It carries several diseases which when exposed to the outer worlds can lead to dangerous aftermath. Approximately 3.4 million people die each year due to water- borne diseases. Besides the diseases wastewater carries, the combination of human waste, solvents, and paints create fumes that aren’t only putrid, but they also expose people to harmful fumes. It also leads to degradation of the quality of soils while reducing it’s fertility and eroding it’s top most essential layer. It may harm the growth of crops and leave the lands barren and unfair to grow anything on the said soil. The crops which do grow are not suggested to be consumed by humans as they carry harmful chemicals inside them.