Most people don’t give a second thought to the water that comes out of their taps, until something goes wrong. Northumbrian Water is at the forefront of water treatment, making sure that the water we use domestically and commercially is fit for purpose.  HEATHER BARRON reports

 

AT Bran Sands, near Redcar on Teesside, a water treatment site exists that few realise is there.

Even fewer give a second thought to what goes on there. Yet none of us would want to imagine what life would be like without it.

The site is Northumbrian Water’s Regional Effluent Treatment Works, which receives and treats the sewage and other waste from around 380,000 businesses and households across the Tees Valley area.

In the region of 150 litres of sewage per person, per day, comes into the site and is treated to strict environmental standards that make the final water clean enough to be released back into the River Tees. The plant’s activity has undoubtedly played its part, along with other investments by Northumbrian Water in its sewer network, in improving the water quality in the Tees, and in the area’s bathing waters.

However, it is not only domestic waste that is treated at Bran Sands. Northumbrian Water runs three treatment “trains”, allowing it to take a wide range of effluent from across the region’s industries, ensuring the right treatment is given to whatever waste comes into the site.

Bran Sands even has a dedicated pilot plant on the site, which allows new waste types and strains to be tested, to ensure it can be treated correctly. New or existing customers are encouraged to provide samples of the effluent so that Northumbrian Water’s experts can test it and ensure it can be treated in compliance with strict environmental legislation.

Northumbrian Water’s Total Water Solutions division also works closely with the Bran Sands team, and with businesses across the area to tanker waste to Bran Sands, on occasions when it cannot be treated on site to make it suitable for discharge into the sewer systems.

This allows businesses to conform to regulations laid out in the Environment Act, which states that waste must be disposed of safely, with no danger to people or the environment.

In sectors such as manufacturing, construction, or process, where waste water might contain chemicals or organic matter that is unsuitable for public sewers, tankering to Bran Sands ensures environmentally focused treatment at a government-approved centre.

And while the water returns to the environment, the sludge that remains within the works, which are situated on top of a membrane covering an old ICI tip, is then used in Northumbrian Water’s industry-leading advanced anaerobic digestion (AAD) facility. This sees the sludge heated in silos where bugs feed on it and then release methane gas, creating “power from poo” electricity that eventually goes back into the National Grid.

Northumbrian Water is the only water company in the UK that uses 100 per cent of the sludge from its sewage treatment in this way. As well as at Bran Sands, the company has a second AAD plant at its treatment works at Howdon, on the north banks of the River Tyne.

Any remaining solids after the AAD process are then used as agricultural fertiliser, making the whole process zero waste.

Using advanced anaerobic digestion, the centre has achieved not only a reduction in carbon emissions, but a 90 per cent reduction in biogas consumption and a 50 per cent reduction in imported electricity. This reduction in the operating costs of the facility means that Northumbrian Water customers’ bills are protected, and the company is able to offer a cost effective and eco-friendly waste water treatment solution.

Tony Rutherford, Process Optimisation Controller at NWG, explains: “The digestion and combined heat and power (CHP) elements of processing sewage and sludge are well established, however conventional treatment is a lengthy method, taking approximately 30 days in traditional digesters.

Where our treatment plants are revolutionary, is the introduction of thermal hydrolysis, which reduces this time by 50 per cent, meaning it takes approximately 15 to 18 days to break the waste down. This reduction in time means that a higher volume of waste can be processed into power more quickly, generating more money for the organisation.

“For companies that deal with human, agricultural, or household waste, Anaerobic Digestion is an ideal solution to consider, it is a more cost-effective option than standard disposal or sewerage costs. With companies increasingly aware of their impact on the environment, it is important to identify that the plants fully recycle the sludge, making it an environmentally-friendly and sustainable method of energy production.

“The AD plants use cutting-edge technology to deliver high-efficiency results at a lower cost to organisations, ensuring that everyone benefits from using the plants. Our Howdon and Bran Sands sites serve many different types of businesses, so even organisations that don’t produce enough waste to warrant purchasing an AD system of their own can benefit from our services. At present, our plants are able to produce 50 per cent more biogas than conventional methods of anaerobic digestion. NWG produces approximately 30,000,000m3 of biogas from sludge per year.

“Not only does the AD process increase income, compared to conventional digestion processes, but also 100 per cent of NWG’s sludge will pass through these plants, ensuring Enhanced Treated product status is achieved for use in agriculture as fertiliser. This means it meets specific EU regulations that reduce the number of micro-organisms in the fertiliser to an almost negligible level.”

  • Businesses interested in knowing more about Northumbrian Water's work at Bran Sands, and how the company can support them in ensuring compliance in their waste water management, can contact 0800 028 3557.