Many large cities in India are already grappling with the water crisis, and the treatment of wastewater is necessary to meet the huge demand. But we can always try to save water with some simple practices. You can save water in your daily life by fixing all the leaking taps in your homes and consuming less water for household purposes. Organizations, like Geo India, are trying to make citizens aware of the consequences of the water shortage and the necessity of saving water.

Wastewater treatment is the process by which wastewater collected from homes and industries is removed of all contaminants and returned back to the water cycle. It is an important part of the conservation of water and an integral step to deal with water shortage.

There are many methods to treat wastewater, depending on the nature of contaminants. Treated wastewater is called effluent, which is then used for domestic, agricultural, and industrial purposes. Here we will discuss five such ways to treat wastewater.

Physical Treatment

Domestic sewage water is treated physically with the help of various processes like sedimentation, aeration, and filtration. The physical process of wastewater treatment is the primary treatment where no chemical or biological enzyme is used.

The solid contaminants in wastewater are removed in three steps—screening, sedimentation, and skimming. Screening is done by removing large solid wastes like rags, stones, paper, etc. from the water. Sedimentation is done by suspending insoluble particles so that the clean water can be extracted when the solid settles down. The process of making solid wastes settle down or float to separate pure water is called skimming.

Aeration is another physical process of treating wastewater. In this method, oxygenated air is circulated through the contaminated water to clean it. Filtration is the method that uses various kinds of filters to separate contaminants and insoluble particles from water. A sand filter is used to remove grease from the water surface by the method of filtration.

Biological Treatment

Biological treatment of wastewater is performed if the water is intended to be re-used for drinking. This process is used to break down organic wastes mixed in wastewater, with the help of microorganisms. The treatment involves three steps to extract pure water that is suitable for drinking.

Aerobic Proce ss –This process uses oxygen to make the bacteria decompose the contaminants and create carbon dioxide for the growth of plants.

ss –This process uses oxygen to make the bacteria decompose the contaminants and create carbon dioxide for the growth of plants. Anaerobic Process – In this process the sludge is fermented at a specific temperature.

– In this process the sludge is fermented at a specific temperature. Composting Process – This process uses oxygen and treats wastewater by mixing sludge with sawdust or different sources of carbon.

The biological process of wastewater treatment is called the secondary treatment of wastewater. This process removes almost all the solid waste from the water except few dissolved chemicals like phosphorus and nitrogen.

Chemical Treatment

Chemical treatment of wastewater involves the use of chemicals like chlorine, ozone, and other oxidizing compounds to purify contaminated water. This method is used for treating both domestic sewage water and industrial wastewater. Chlorination is done by mixing chlorine and sodium hypochlorite. This process kills the decomposing bacteria of wastewater. Disinfectants like ozone do not allow bacteria to reproduce, thus cleaning contaminated water.

Industrial wastewater is treated by the process of neutralization. This process involves the use of an acid or base to regulate its pH level. For acidic wastewater treatment bases like lime is used. Carbon is also used for purifying contaminated water by chemical treatment. The most used chemicals for chemical treatment of wastewater are metals having more than one valence.

Sludge Treatment

The sludge treatment of wastewater separates solids from the liquid. A separation device like centrifuge is used for the purpose. The cost of disposal of solid waste depends on the residual moisture in the separated solid waste. This method is the most prominent process to de-contaminate industrial wastewater or sewage water.

Sludge is also collected by physical treatment of wastewater. The sludge is then separated from moisture completely, and then treated to be used for agricultural purpose. The liquid separated from the sludge is purified by aeration.

Natural Treatment

Natural treatment of wastewater is a cost-effective and alternative wastewater treatment method. Wastewater can be treated naturally, by constructing wetlands where the natural biological process of purification of wastewater can take place.

Another method of treating wastewater naturally is by creating a small pond to purify contaminated water. While such a method is not suitable for industrially contaminated water, water having organic wastes and hydraulic waste can be purified efficiently. The natural method of wastewater treatment has a simpler design and reduces carbon footprint as well. But the weather conditions should be suitable to carry out this method.

Conclusion

Water gets polluted by industrial waste from different factories. So, wastewater management is necessary to make the water safe enough to be consumed and used for agricultural purposes. But we can always try to reduce polluting water bodies by not throwing garbage and organic waste. Many homeowners throw chemicals, paints, and other toxic waste in their sewer lines that mix with the water making it unusable. With a few simple changes, we can prevent water pollution and in turn save the environment.