How does wastewater affect the environment?
In the UK we are lucky to have a modern sewage system that means we do not have to think much about what happens to the wastewater we produce. It provides us with a safe and hygienic way to dispose of wastewater which in turn protects us from the risk of infection and disease. Our excellent wastewater treatment processes mean we have reliable access to clean water for drinking and industrial use.
But it’s no secret that pollution is a real problem, and wastewater is one pollutant that is often less talked about. In this blog post, we explore how wastewater affects the environment and how wastewater treatment and reuse is helping to have a positive impact.
What is wastewater?
Wastewater refers to any liquid waste or sewage that comes from homes, hospitals, factories and any other building that uses water in its facilities. From flushing the toilet to the vast amount of wastewater that flows out of industrial plants, we all contribute to it. Unless wastewater is properly treated, it can harm public health and the environment.
How bad is wastewater for the environment?
Untreated wastewater can have a severely detrimental impact on the environment. The fact we are making water unusable means we are literally draining our water supplies.
That waste is then being dumped into our existing bodies of water, contaminating it with harmful substances such as heavy metals, pathogens, toxic chemicals, oil and grease, sludge, organic and inorganic materials.
This process presents numerous hazards for humans, as well as huge amounts of wildlife, including hundreds of species of fish that live in water. These harmful substances can also find their way into the soil, causing it to yield fewer crops at a slower rate.
So, what can we do about it?
Waste not, want not...
Nature has an incredible ability to cope with small amounts of water wastes and pollution. But it would simply be overwhelmed if we didn’t treat the billions of gallons of wastewater and sewage produced every day before releasing it back into the environment.
Today, wastewater treatment plants are large complex facilities that use multiple technologies to remove up to 99% of all pollutants in wastewater.
Wastewater treatment is a process used to remove contaminants from the water before the remaining water, called effluent, is discharged back into the water cycle. Once returned to the water cycle, the effluent creates an acceptable impact on the environment - or can be reused for various purposes.
4 phases of wastewater treatment
Primary treatment - Wastewater is placed in holding tanks and solids settle to the bottom where they are collected. Fats and oils are then scraped off the top and the remaining liquid is sent on for secondary treatment. Meanwhile, leftover sludge (when treated separately) can be used for other commercial purposes.
Dissolved Air Flotation (DAF) is one primary treatment that can be used to concentrate and remove a wide range of suspended solids in wastewater. This process can remove up to 60% of suspended solids and organic loads.
Secondary treatment - This phase makes use of oxidation to further purify wastewater. Coagulants and flocculant chemicals are used for further solids removal, water clarification, lime softening, sludge thickening and solids dewatering. This process can result in the removal of more than 90% of suspended solids and organic loads.
Tertiary treatment - This phase is used to improve the quality of the effluent resulting from primary and secondary treatment processes. It involves sand filtration, nitrifying bacteria and lagooning.
Disinfection - This is the final stage, removing microbes and odours from the wastewater. It can include the use of ozone, ultraviolet (UV) light or chlorine dioxide. The latter is particularly effective at removing microorganisms such as bacteria, viruses and parasites.
You can read more about the wastewater treatment process in our previous blog post here.
Once the water has been disinfected it can be used again in a variety of industrial and agricultural applications. There are, however, strict environmental regulations around the safe disposal and reuse of water and sludge, which you can read about here.
And don’t forget, regular testing is essential for ensuring that the water you’re reusing is safe and within the appropriate limits for preventing microbiological growth.
Water recycling and reuse
With the rising climate crisis and growing spotlight on companies to embed more eco-friendly practices, many companies are recognising that there is an opportunity to manage their water in a highly sustainable way. Technology can be used that enables wastewater to be reused, while bespoke machines, equipment and processes also exist to help companies transform wastewater into energy.
Being able to efficiently recycle wastewater and reducing the amount of sludge produced by current processes is not only about protecting the environment and adding to your green credentials. With waste supply and disposal costs on the rise, it can save you significant amounts of money by reducing your required intake of freshwater and the cost of sludge disposal too.
WCS Group’s Wastewater and Dewatering team provides specialist commercial and industrial water treatment knowledge which enables wastewater to be re-used and sludge to be minimised, therefore reducing discharge and cost. To find out more about how our solutions could help you, click here.
Written by James Greenwood
James Greenwood as been working in the Water Treatment and Water Hygiene Industry for over 20 years. He is currently the Sales and Marketing Director for WCS Group the largest water hygiene and treatment Company in the UK. James has been instrumental in bringing significant innovations to the UK market over the years always focusing on enhancing client’s compliance and delivering true return on investment projects offering monetary and environmental savings.