An Overview Of Water Effluent Sewage Treatment

Effluent is basically treated sewage from places like septic tanks or sewage treatment plants. Some call it "trade effluent" or just "wastewater." It is not waste from kitchens, toilets, or surface water. Any business or industry can make and release effluent. Usually, it goes straight into the main sewer system and cannot go into a river or lake unless it is cleaned and treated first. Understanding the value of every drop, many ETP and STP plant manufacturers in Delhi are making significant efforts to achieve a sustainable civilization with the help of their advanced sewage treatment plants. 

Effluent typically has some contaminants in it, such as:

• Detergents 
• Fats, oils and greases (FOGs) 
• Chemicals 
• Solids 
• Heavy metal rinses 
• Food waste

Wastewater Treatment

The remarkable wastewater treatment process of ETP and STP plant manufacturers in Delhi aims to get rid of as many suspended solids as they can before letting the treated water go back into the environment. The first round of treatment (primary treatment) removes around 60% of these solids). After the second round of treatment (secondary treatment), more than 90% of the suspended solids are taken out.

1. Primary Treatment 

Primary treatment gets rid of things that can either float or easily settle down. It involves basic steps like screening, breaking down, getting rid of grit, and letting the solid stuff settle.

• Screening: Screens, made of long metal bars, stop things like wood or rags from blocking pipes. In modern places, machines clean these screens, and the stuff they catch is buried on-site. A grinder might be used to break down things that get through the screens. The broken bits are taken out later by settling or floating. 
• Removing Grit: Grit chambers are like long tanks that slow down the water. This helps things like sand or coffee grounds to settle at the bottom. This matters a lot in places with combined sewer systems, where a lot of dirt washes off the streets during a storm. 
• Settling the Remaining Solid: After this, sedimentation tanks, or primary clarifiers, let the remaining solids settle down. This takes a couple of hours as the sewage moves through slowly. The settled stuff, called raw or primary sludge, is scraped along the tank bottom by machines. It is collected and pumped out for removal. Devices on the surface take away things like grease.

2. Secondary Treatment

Secondary treatment deals with the stuff that dissolves or stays in the water after the first round. It is about getting rid of more solids and organic matter.

• Biological Processes: Tiny living things, like microbes, eat up the organic impurities in the water as their food. They turn them into carbon dioxide, water, and energy for their own growth. The sewage treatment plant provides the right environment, even if it's made of steel and concrete, for this natural process to happen. 
• Removing the Dissolved Part: Getting rid of the dissolved organic matter at the treatment plant helps keep the balance of oxygen in the water of a stream, river, or lake. There are three main ways to do this: using a trickling filter, the activated sludge process, or an oxidation pond. Another less common method is the rotating biological contactor.

How Effluent Treatment Plant (ETP) Works?

The treatment approach of ETP Plant Supplier involves getting rid of suspended particles, and dissolved organic matter, and handling sludge for disposal. Here are the different steps:

• Equalization: The equalization tank balances raw effluent from various units by collecting it in a mixed effluent tank. It is then pumped into an aeration tank, which also acts as an equalization tank. A floating aerator homogenizes the effluent before it is sent to the neutralization tank for treatment. 
• PH Control: The pH should be between 5.5 and 9.0 according to the Bureau of Indian Standards (BIS). pH neutralization adjusts the pH using bases for acidic waste and acids for alkali waste. 
• Coagulation: Liquid aluminum sulfate is added to untreated water in the coagulation process. This causes small dirt particles to stick together, forming larger, heavier particles that settle and can be easily removed through settling and filtration.
• Sedimentation: In this slow process, heavy particles settle to the bottom, forming sludge. Sludge is the term for the particles that collect at the bottom of a container. 
• Filtration: Water passes through filters made of sand and gravel layers to remove particulates. Regular backwashing is necessary to clean these filters. 
• Disinfection: Water is disinfected with chlorine before entering the distribution system to ensure it is safe and clean. 
• Sludge Drying: Sedimentation collects solids that are then transported to drying beds. Sludge charging is stopped when the thickness reaches around 300 mm, allowing natural evaporation to dry it off, which takes about ten days.

History of Sewage Treatment

People used to think that if you threw a little sewage into a flowing river, it would naturally clean itself. But when towns get big and produce a lot of sewage, just letting it flow does not work. So, we started building sewage treatment plants in the late 1800s and early 1900s, mainly in the UK and the US. Instead of dumping sewage directly into the water, we began using processes like physical, biological, and chemical methods to take out the bad stuff. 

In the 1900s, we also changed how we collect sewage, keeping stormwater separate from household wastewater. This way, treatment plants would not get overwhelmed during rainy times. As people became more worried about the environment around the 1950s, rules got stricter, and we needed better treatment. Industries had to treat their wastewater too, so harmful chemicals would not mess up the treatment plants. 

By the middle of the 1900s, technology improved, and we could almost completely clean sewage. But it was so expensive that we did not always do it. Treatment plants got big and used a lot of energy. When oil prices went up in the 1970s, we started caring more about saving energy. So, we started looking into other ways to get rid of sewage, like putting it in the ground. These simpler methods might save energy, and they could even recycle nutrients and refill groundwater.

Conclusion 

Water is considered polluted when it has too many impurities, which makes it unsuitable for specific purposes like drinking, swimming, or fishing. Wastewater treatment is the process of removing these impurities from sewage before it gets into natural water sources like rivers, lakes, and oceans. The extent of treatment needed depends on local environmental factors and government standards.