Once it’s disappeared down the drain, most of us don’t give our water a second thought. However, it’s just the start of the journey for wastewater and its microscopic sludge. Here’s everything you need to know!
The UK government defines urban wastewater as the mixture of water that has been used by homes, industries discharging into sewers, and rainwater runoff. In other words, any water that enters the sewer system can be called wastewater, including industrial and agricultural process water.
Sludge is the solid, formerly soluble waste material left behind by water treatment, wastewater treatment, or sanitation treatment. It is a mixture of solids and liquids and contains both organic and inorganic compounds, as well as microorganisms. The types of compound depend upon whether the wastewater originates from process water, sewage, or industrial settings.
Almost every commercial environment generates wastewater. In office and retail settings, the main sources are toilets, kitchens, and wash areas. In commercial settings, sites such as vehicle repair shops and car washes are major contributors. Most manufacturing and industrial settings use water for processes including pipe flushing, and all farms generate large quantities of wastewater. Rainwater is also a very important contributor.
Wastewater contains around 99.9% water, all of which can be safely reused. The 0.01% that remains forms sludge. Therefore, sanitising 1000 gallons of wastewater will generate around 0.1 gallons of sludge.
Sludge has a surprising number of uses. It is often rich in nutrients such as nitrogen and phosphorus, both key ingredients in fertiliser. Its viscous properties mean sludge is also used to control soil erosion and improve landscaping. In some parts of Europe, it is increasingly being used as an alternative fuel source, especially in the cement industry. Using the same principles, sludge that has been anaerobically treated can be used to heat homes, leading the European Commission to highlight it as an important element of sustainable energy strategies.
Rainwater harvesting is important in domestic, commercial, and industrial settings. When it is properly harvested, rainwater can be used for a variety of grey-water applications such as toilets. Although sludge contains many helpful nutrients, it also contains harmful heavy metals and dangerous bacteria, so it is important to remove it from rainwater. Good rainwater harvesting systems contain filters to minimise the volume of sediment in the water, and a simple cleaning schedule using eco-friendly detergents can prevent the build-up of sludge.
At Enduramaxx, we support businesses to create water systems that are clean, safe, and cost-effective. To find out more about how you can save money whilst helping the environment, please get in touch.
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