What is biological waste water treatment?
Biological wastewater treatment leverages the effects of bacteria and other microorganisms to purify water.
Biological wastewater treatment is a seemingly simple process because it uses natural processes to aid in the decomposition of organic matter, but in reality it is a complex and complete interface between biology and biochemistry. Biological treatment relies on bacteria, nematodes, or other small organisms to break down organic waste using normal cellular processes. Sewage is usually high in organic matter such as garbage, sewage and partially digested foods. It may also contain pathogens, heavy metals and toxins.
What is the purpose of biological wastewater treatment?
The purpose of biological wastewater treatment is to create a system that can easily collect and dispose of decomposition results. Biological treatments are used around the world because they are more effective and economical than many mechanical or chemical processes.
What are the two types of biological processes?
Biological processing is usually divided into aerobic and anaerobic processes.
"Aerobic" refers to the process in which oxygen is present, and
"Anaerobic" refers to the biological process in which oxygen is not present.
Scientists have been able to control and improve both aerobic and anaerobic biological processes for optimal removal of organic matter from wastewater.
Biological wastewater treatment is widely used as a post-treatment process to remove substances remaining after pre-treatment using processes such as Dissolve Air Flotation (DAF). Primary water treatment removes substances such as sediments and oils from wastewater.
Aerobic wastewater treatment
Aerobic wastewater treatment methods include simple septic tanks or aerobic tanks, Surface and spray aeration; Liquefaction; Oxidation ponds, watering filters; Pond and lagoon-based treatments, and aerobic digestion.
Biological treatment processes also include various types of filtration. Diffusion ventilation systems can be used to maximize oxygen transfer and minimize odours during wastewater treatment. An old example of an aerobic biological treatment process is the activated sludge process. It is widely used for secondary treatment of domestic wastewater and industrial wastewater. It is very suitable for treating the flow of organic matter and highly biodegradable waste and is widely used for treating urban wastewater, wastewater from the food industry such as pulp and paper factories or meatprocessing and carbonaceous industrial waste.
In recent years, technological advances have changed biological processes. An example is the Membrane Aeration Bio film Reactor (MABR), which improves this process and reduces the energy used for aeration by 90%. This is usually the most energy-intensive stage of traditional biological processing.
Nitrification/de-nitrification are achieved by a bio film formed on the membrane. The result is wastewater suitable for irrigation and thus, release to the environment.
Most old plants around the world use activated sludge treatment or other old aerobic treatment processes. Such systems are time consuming and expensive to replace or do not have the space required for expansion.
In just a few years, MABR has matured into mature technology and has undertaken a large-scale.
In contrast, anaerobic treatment uses bacteria to break down organic matter in an oxygen-free environment. Lagoons and septic tanks can use anaerobic processes, but the most well-known anaerobic treatment is anaerobic digestion, which is used to treat food and beverage production wastewater, urban wastewater, chemical wastewater, and agricultural waste.
Anaerobic digestion promotes energy recovery, one of the most powerful areas of resource recovery. In this form of energy recovery, also known as the conversion of waste to energy, biogas, which consists primarily of methane, is produced by anaerobic fermentation. Operators can use it to generate energy, support operations towards net-zero energy, or turn waste flow into revenue flow.
The type of biological treatment chosen for wastewater treatment, whether aerobic or anaerobic, depends on a variety of factors, including compliance with environmental quality regulations for emissions.
Biological treatments are often complemented by additional treatment steps such as chlorination and UV treatment and various filtration options such as activated charcoal.While biological treatment has a long history, it continues to evolve in ways that make it more effective, efficient, and available.