Back to: MICROBIOLOGY 400 LEVEL
Welcome to class!
Hello brilliant one! I’m so glad you’re here today, eager to learn something very practical and important. Have you ever thought about what happens to the water that goes down the sink after washing plates or the water from factories? That water is no longer clean—it becomes wastewater. Today, we’ll be learning about the composition of domestic and industrial wastewater. This knowledge is vital for solving many environmental and public health problems we face in Nigeria and across Africa.
Composition Of Domestic And Industrial Wastewater
Wastewater is used water that contains various substances removed from homes, schools, factories, and businesses. It includes everything from bath water and urine to chemicals and waste from production processes. There are two main types of wastewater:
1. Domestic Wastewater (Sewage)
Domestic wastewater comes from households, schools, restaurants, and offices. It includes:
Organic Matter: Like food particles, fats, oils, and grease from kitchens. These provide nutrients for bacteria but can cause pollution if untreated.
Human Waste: Faeces and urine contain nitrogen, phosphorus, and disease-causing microorganisms.
Soaps and Detergents: These come from bathing, washing clothes, and cleaning. They contain phosphates and other chemicals.
Hair, Dirt, and Paper: From sinks, showers, and toilets.
Pathogens: Microorganisms like bacteria (E. coli), viruses, and parasites that can cause diseases such as cholera and typhoid.
In urban areas like Lagos, if domestic wastewater is not properly managed, it can pollute rivers, causing outbreaks of waterborne diseases.
2. Industrial Wastewater
This comes from factories and production facilities—such as oil refineries, textile companies, breweries, and food processing plants. Its composition depends on the type of industry:
Heavy Metals: Such as lead, mercury, chromium, and cadmium from industries like battery manufacturing or metal plating.
Toxic Chemicals: Including acids, alkalis, and solvents used in production processes.
Organic Pollutants: Like alcohol, sugar residues, and oils from food and beverage industries.
Suspended Solids: These include sand, dust, or leftover raw materials.
Dyes and Colourants: From textile and leather industries, which can colour rivers and harm aquatic life.
In places like Aba or Kano where manufacturing is common, untreated industrial wastewater can damage soil, poison water sources, and harm people and animals.
Why This Matters
Understanding what is in wastewater helps us treat it properly before it is released back into the environment. Wastewater treatment protects our rivers, food systems, and public health.
Summary
- Wastewater is used water that contains unwanted materials.
- Domestic wastewater comes from homes and public places.
- It contains organic matter, faeces, soaps, and disease-causing microbes.
- Industrial wastewater comes from factories and depends on the type of industry.
- It may contain heavy metals, toxic chemicals, dyes, and other dangerous substances.
- Domestic and industrial wastewaters can pollute the environment if untreated.
- Untreated sewage can spread diseases like cholera and typhoid.
- Industrial waste can harm rivers, soil, and aquatic life.
- Proper wastewater management is crucial for public health and environmental safety.
Evaluation
- List three components commonly found in domestic wastewater.
- Mention two harmful substances found in industrial wastewater and their sources.
- Why is it important to treat wastewater before releasing it into the environment?
understanding wastewater, you’re one step closer to becoming part of the solution to some of Nigeria’s biggest environmental challenges. Keep showing up, keep learning, and keep believing in yourself. Afrilearn is proud of you—see you in the next class!