Learn about how to treat wastewater? What are the steps of wastewater treatment?
Wastewater from domestic, industrial or medical production contains many serious pollutants if not treated properly. Establishing a wastewater treatment system not only helps to remove toxic components in water but is also a necessary solution to protect the environment and promote the reuse of precious water resources. The following article by GREEN IN will answer your questions about wastewater treatment!
1. Concept of wastewater treatment
Wastewater is a by-product of living, production and service activities, from households to businesses. To control the impact of wastewater on the environment, it is necessary to implement wastewater treatment - a process that uses mechanical, chemical and biological methods to remove or reduce harmful substances. This process ensures that wastewater before being discharged or reused has met safety standards, limiting health risks and environmental pollution.
A typical example is domestic wastewater, formed from activities such as washing, cooking, bathing, etc. in households and residential areas. This is a common type of wastewater that needs to be collected and treated properly.
2. What is a wastewater treatment system?
Wastewater Treatment System is a set of specialized technologies and equipment used to treat polluted water. This system can be customized according to the specific characteristics of water volume, pollution level and treatment purpose.
An effective system should meet the following criteria:
- Ability to thoroughly treat harmful substances, ensuring that treated water meets QCVN standards issued by the Ministry of Health.
- Reasonable investment cost, both economical and still ensures technical efficiency.
- Easy to upgrade and expand as processing needs change over time.
- Flexible chemical addition to meet diverse input water conditions.
3. Steps in the wastewater treatment process
To ensure that wastewater does not have a negative impact on the natural environment, organizations and individuals need to build a systematic treatment system. Below are the main stages in this process:
Mechanical and physical treatment
The first stage is to remove insoluble impurities such as garbage, gravel, sand by using equipment such as screens, trash racks or sand settling tanks. This is the foundation step to help the next stages operate more effectively.
Chemical and physical treatment
This is followed by pH adjustment, coagulation and flocculation processes to remove heavy metals and small solids that are difficult to remove mechanically. Chemical reactions convert the contaminants into more manageable forms.
Biological treatment
This stage applies microbiological methods such as aerobic and anaerobic to decompose organic substances dissolved in water such as H2S, NH3, nitrogen, etc. This is an important part in removing biological pollutants.
4. Modern wastewater treatment technologies
Regulating technology: This technology helps stabilize the flow and quality of water before entering the main treatment system. Wastewater will be stored and pumped at a predetermined flow rate to avoid overloading the treatment tanks.
pH neutralization technology: Used when wastewater is acidic or alkaline beyond the threshold. The system will add neutralizers to bring the pH to the appropriate level for biological processes and discharge.
Coagulation and flocculation: By adding alum, iron alum or flocculating chemicals, small particles in water will clump together into large flocs and easily settle or be filtered out.
Precipitation method: Mainly used to remove heavy metals such as lead, zinc, mercury through the reaction to form insoluble precipitates in water. pH adjustment is often required to optimize this process.
Flotation technology: Applied to wastewater containing grease or floating substances. By injecting air to create bubbles, light particles will float and be separated from the water stream.
Settling Tank: Based on the difference in density, this process allows the solids to settle and separate from the water. This is one of the most basic and effective steps.
Aerobic biological treatment: Microorganisms use oxygen to decompose organic matter, effectively cleaning water. This technology requires continuous oxygen supplementation and a suitable environment for microorganisms to grow.
Aerator: Provides oxygen for microorganisms and supports the oxidation of metals such as iron and manganese. Aeration also helps increase the DO content in water to meet discharge requirements.
Tertiary wastewater treatment: Includes the following steps: filtration – adsorption – ion exchange. This process is used to remove residual substances after biological and chemical treatment, especially toxic ions or organic substances that are difficult to decompose.
5. Conclusion
In the context of increasingly depleted water resources and the living environment facing many challenges, building a systematic wastewater treatment system is a must for individuals, organizations and businesses. Current legal regulations such as QCVN on wastewater, or Government decrees have clearly stated responsibilities in wastewater treatment. An efficient treatment system not only helps businesses save costs in the long run, but is also a way to demonstrate social responsibility and protect a green future for the community. Follow now GREEN IN to receive more useful information!