How water reuse can help close the EC water demand gap
02 December 2020 | Web Article Number: ME202021426
Water management and wastewater reuse is essential if South Africa, and the Eastern Cape in particular, is to plug the gap between supply and growing demand, writes Joyce Moganedi, Sales Manager for Power & Water, ABB Energy Industries in South Africa.
TODAY, four billion people experience severe water scarcity annually, according to the World Business Council for Sustainable Development.
On a global level, water challenges are well known, with a mushrooming global population, urbanization and economic development predicted to increase global demand by 50% by 2030, outstripping supply by 40%.
In South Africa only 27% of the country’s total water production is directed to the consumption, which is already significantly higher than average, of over 60 million people. The mismanagement of water, alongside severe droughts, has created ‘disaster status’ for much of the nation, with the situation in the Eastern Cape particularly precarious. In 2019 Adelaide experienced critical failure which had a crippling impact on local people and industry, much of which is farming and agriculture.
Following multi-year droughts many towns and businesses have been threatened by total water failures. In the last three years alone five municipalities, the Sarah Baartman District, Nelson Mandela Bay, Amathole District, OR Tambo and the Joe Gqabi district, have all been declared a state of disaster due to drought, with key dams at critically low levels.
There is a need to urgently regain control of the water situation in South Africa, and specifically in the Eastern Cape. Municipalities need to think anew about water. We can no longer look to expand the distribution of water without first ensuring that there is enough supply or putting in place measures to control use.
One solution is water reuse: reclaiming, treating and purifying used water and wastewater and repurposing it back into the water cycle. Unfortunately, this strategy is not currently widely adopted. In fact, only a fifth of wastewater generated by society is now reused.
One of the primary problems in the treatment of wastewater is the removal of poorly degradable contaminants and micro pollutants. These pollutants accumulate in surface and ground waters, with treatment requiring more advanced water and wastewater treatment technologies that need even higher levels of energy consumption. As a result, the operating costs often eat into the revenues of the water companies.
The most effective way to avoid this is to improve plant efficiency, through automating process control and digital solutions that reduce energy consumption and operating costs. ABB helps water companies and municipalities to achieve this by providing integrated automation & electrical solutions, instrumentation and digital services for the entire water and wastewater cycle.
In automating all elements of the operational process, utilities can access big data and in so doing gain complete visibility of operations in real time. Analysis of this data helps to identify trends, find savings efficiencies to optimize performance, manage leaks and reduce waste and forecast availability based on dam levels. This information can be used to make more informed accurate decisions aimed around ensuring reliability and security of water lowering stress levels.
One example where ABB is supporting water reuse is the Tuas Water Reclamation Plant (WRP) in Singapore. Considered one of the world’s most water-stressed nations, with no natural water sources, the Tuas WRP is a key component in the nation’s strategy to ensure water security. The plant will receive used water flows from the western part of Singapore via two separate deep tunnels, applying membrane bioreactor (MBR) technology to treat and purify 650,000m3/day of domestic used water to generate new drinking water. A further 150,000m3/day of used industrial water will also be treated and sent back to industries for reuse.
ABB will deliver complete site-wide monitoring and control system for the plant, deploying process control systems across multiple facilities at the site, including pumping stations, a wet weather facility, and biosolids, domestic liquid and industrial liquid modules into one unified control platform.
The solution will enable a small team of operators on site to gain complete visibility of operations and access to all process data to take decisions that optimize performance in real time.