In the past years, we started to become worried about the consequences of water scarcity or low quality. Among the ongoing developments, what has grown in the last few years is the practice of wastewater biological treatment. This has transformed the thinking of the majority of the population by making green and more environmentally friendly choices. The process revolves around treating and reusing water, and reducing wastage to use it for irrigation and related purposes. The process involves the use of microorganisms for water purification and aerobic treatment to make the water reusable.
In this guide, we shall shed some light on the steps that go into wastewater treatment and its meaning. And last, but not least, we shall know the reasons behind its popularity, current trends, and the sustainability of the process.
What is Wastewater Biological Treatment?
To treat wastewater biologically, some microorganisms are used in the process and include bacteria, fungi, and protozoa. Therefore, they are able to break down the organic impurities and pollutants in water, thus killing them. There are no hazardous procedures in this process because it accelerates the natural process of purifying water by decomposing it.
We can sub-categorize the types and procedures, that too, depending on the type of microorganisms involved with different wastewater biological treatment methods:
1. Aerobic Treatment
Firstly, the treatment primarily uses the microorganisms from highly oxygen-rich environments to break down the organic waste matter. This process helps with the purification and recovery of nitrogen in the wastewater.
2. Anaerobic Treatment
The process of anaerobic treatment goes through stages as it is efficient even in water that is strongly contaminated. The bacteria (Hydrolytic bacteria and Acidogenic bacteria) and archaea (Methanogenic archaea) taking part in this process can break organic matter without even the need to have oxygen. Hydrogen, carbon dioxide, acetic acid, and biogas are all released as end compounds from anaerobic treatment of wastewater.
3. Anoxic Treatment
Lastly, this treatment was developed with a specific aim, that is, to eliminate nitrates after completing aerobic treatment. Why? Since microorganisms do not grow in the presence of oxygen, but grow in the presence of nitrates, owing to after aerobic treatment.
What is the Process of Wastewater Biological Treatment?
The process of wastewater biological treatment is divided into four processes that should be followed in their chronological order. These four steps of biological treatment of wastewater are further described below:
Phase 1: Removal of Debris and Grit
Firstly, this step is constructed by eliminating big and small items in the water that can easily destroy the machinery. These items can be sticks, rags, rocks, stones, debris, grit, gravel, and other inorganic matter that gets eliminated with wastewater treatment screens.
Phase 2: Sludge Removal
This, in other words, sludge removal is to remove the clumps or floating solids or organic/inorganic matter in the wastewater that too, with the help of the sedimentation process. The heaviest material (sludge) is deposited at the bottom, and this, together with the floating material, is removed, and the remaining portion of the water proceeds to the next stage.
Phase 3: Biological Treatment
Now, this is the primary process of the entire process of wastewater biological treatment in which microbial communities are grown and controlled. All of this is to eliminate as much organic waste as possible by letting them feed off it. These microbes consume only the organic matter and give out gases until they eliminate all the organic matter present.
Phase 4: Filtration and Disinfection
Then, high-tech filtration, chemical, and disinfection are the last stage of the wastewater biological treatment. This is because this step is only about eliminating any remaining contaminants to make the water fit for discharge.
Current Wastewater Treatment Trends
In terms of wastewater treatment trends, there have been numerous new developments and innovations that have come in to bring the process to a new level of energy efficiency and effectiveness in the following ways:
1. Water Reuse and Reclamation
Current trends have offered advanced filtration and disinfection systems such as reverse osmosis and UV irradiation, for quality treated water. Then, the treatment plants can use the recovered product in non-potable applications, such as in agriculture, industrial processes, and toilet flushing.
2. Eco-Friendly and Nature-Based Solutions
Wetland and phytoremediation (plants to clean up water) are also proving to be less expensive and sustainable for the smaller communities or even individual industries. In other words, it is nothing more than how the wastewater biological treatment solutions are turning the planet greener.
3. The Development of Membrane Bioreactor
The membrane bioreactors combine wastewater biological treatment with state-of-the-art filtration membranes to achieve high-quality effluent. In other words, they are small in size, manage high-strength wastewater, and reduce sludge formation and energy consumption by means of an efficient aeration system.
4. Treatment Systems that are Positive in Energy
The new systems use biogas, solar power, and microbial fuel cells to produce more energy than they use. Such a transition to net-zero operations minimizes the use of external power grids and minimizes carbon footprints. Likewise, facilities all over the world implement them because of the need to meet the sustainability objectives without compromising the effectiveness of the treatment.
5. Innovations of Electrochemical Treatment
Electrochemical processes to attack stubborn pollutants, such as the electrocoagulation and electrooxidation, without the use of chemical additives. They use electricity to decompose organics, heavy metals, and pharmaceuticals in compact and modular systems. This is trending with faster and less sludge-generating decentralized applications.
Is the Wastewater Treatment Process Sustainable?
Some of you might now be wondering, “Is wastewater treatment sustainable?”, after learning about the process of treating wastewater biologically. The simple response to this is yes. The details of this process being sustainable over the long term are, however, detailed and listed below:
1. Use of Organic Resources
This is unlike the usual means of wastewater treatment, which involves the use of heavy and hazardous chemicals. The worst part? This technique depends on accelerating the natural process of organic decomposition through the use of microorganisms.
2. Savings on Resources
Water treatment consumes a significant amount of resources as financial resources to buy chemicals, store them, and use machinery, etc. Likewise, wastewater biological treatment enables nature to do its thing by not entailing a lot of manual processes or interventions.
3. Fuel and Biogas production
This treatment process produces a lot of biogas, which is a renewable source of energy in its anaerobic section. This way, treatment plants will be in a position to reduce their overall carbon footprint by using green energy.
4. Water Reuse and Conservation
Rather than discharging polluted water into the natural resources, the process purifies the water naturally to ensure its reusability. In this manner, we save the natural resources from pollution by treating wastewater in a manner that can be reused.
Biological Wastewater Treatment to a Greener Future
As the modern age of innovation and industrialism sets in, it becomes a little hard to attract attention towards preserving our world. But even small projects, such as wastewater biological treatment, we get to make small steps towards a green future. Water is the most naturally available resource, and the one that is the most abused in today’s world. Yet today, we can make a little step in the right direction by respecting what sustains and gives us life.
Frequently Asked Questions (FAQs)
1. What is unique about the moving bed biofilm reactor (MBBR) in wastewater bio-treatment processes?
MD Biofilm reactors involve the utilization of plastic carriers that microorganisms can colonize to develop strong biofilms to degrade organic materials. Now, aerated tanks have freely floating carriers that enhance the retention of biomass and the capacity to treat it. In other words, this technique is effective in dealing with shock loads and reducing sludge generation in small designs.
2. What are the benefits of lagoon systems in supplementing the process of biological treatment of wastewater?
The lagoon systems expose the wastewater to the sun and wind, and K-12, through which the algae and bacteria collaborate to oxidize organics. Facultative lagoons are stratified into aerobic top and anaerobic bottom layers to have a complete pollutant removal. They do well in hot climates, and they provide low-cost solutions to rural societies in the global world.
3. What are the advantages of nitrifying bacteria in the biological treatment of wastewater?
Ammonia is oxidized sequentially through the action of nitrifying bacteria to produce nitrates and nitrites in aerated zones. Likewise, they facilitate the elimination of nitrogen when combined with denitrifying microorganisms during anoxic processes efficiently. This, to sum up, is a biological means of averting the eutrophication of the water bodies receiving the discharge.