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‘Watt’ great news- Bellville WWTP is South Africa’s first municipal wastewater treatment plant to achieve global energy management standard<table cellspacing="0" width="100%" class="ms-rteTable-default"><tbody><tr><td class="ms-rteTable-default" style="width:100%;"><p><strong>What to know about Bellville WWTP:</strong></p><ul><li>This facility performs the critical function of treating sewage/wastewater coming from homes, businesses and industries (referred to as influent) before releasing this as treated effluent into the environment via our waterways.</li><li>It services about 592 000 people in areas such as Durbanville, Kuils River, Brackenfell and Bellville.</li><li>It treats about 44,3 million litres of sewage a day. <br></li></ul></td></tr></tbody></table><p>​<br></p><span><p>The South African Bureau of Standards (SABS) issued the certification to the City's Water and Sanitation Directorate during a ceremony today at the Bellville WWTP.</p><p> <strong>The energy-efficiency improvement at Bellville WWT</strong><strong><em>P</em></strong><strong> has resulted in some of these key benefits:</strong></p><ul><li><strong>More than R1 million</strong><strong> in </strong><strong>savings a year for electricity costs.</strong></li><li><strong>More than one million kWh savings a year.</strong></li><li><strong>Reducing the carbon dioxide emission of 1000 tonnes a year.</strong></li><li><strong>The energy saved is equivalent to treating 3000 million litres of wastewater a year. </strong>​​</li></ul></span><span><figure class="subtopic-fullsize-img"> </figure><div><span><p><img src="" class="responsive" alt="" style="width:818px;" /></p>​​</span><span><br></span></div>​​</span><span>​​</span>Over the past four years, the City has invested more than R179,8 million at Bellville WWTP. Recently two contracts were approved that will see a further estimated investment of more than R120 million for the last phase of the Diffused Aeration upgrade.<span><p> 'This is an incredible achievement and we are extremely proud of all our staff who have worked together over the past few years on this initiative. The ISO certification represents the culmination of their efforts, and has put Cape Town on the wastewater energy-efficiency map, not only in South Africa, but also globally. This recognition affirms the City's commitment to improving the quality of treated effluent, adopting energy-efficient operations, and reducing the impact of climate change by lowering carbon dioxide emissions. In the face of constant load-shedding, energy efficiency in our operations is particularly important, as every kWh matters,' said Acting Mayoral Committee Member for Water and Sanitation, Councillor Siseko Mbandezi.</p><p> The energy-efficiency journey started in 2018.</p> <figure class="subtopic-fullsize-img"> </figure></span><span></span><span><figure class="subtopic-fullsize-img"> </figure><div><span> <figure class="subtopic-fullsize-img"> <img src="" class="responsive" alt="" style="width:949px;" /> </figure>​​</span>​<strong>Pursuing this ISO 50001:2018 Energy Management Standard certification involved:</strong></div></span><span><ul><li><strong>Developing an Energy Policy</strong>. This includes the City's commitment to improving both WWTP energy performance and the Energy Management System itself, and supports the procurement of energy-efficient products and services, plant and equipment upgrades, and considers retrofit design to improve the plant's energy performance.<br><br></li><li><strong>Training staff</strong> so that everyone is made aware of their role in reducing energy consumption in the operation. <br> </li><li>The Bellville WWTW management team <strong>conducting an energy review</strong> that involved the trending of past energy consumption, identifying significant energy users (SEUs), and the development of energy baselines. This used plant inflow meters that measure the quantity of wastewater, electrical billing and process unit electrical consumption meters to collate information and correlate in a statistical model, process parameters such as wastewater flow throughput (quantity) to the electrical energy consumption of the plant.<br> </li><li>Using relevant variable data to <strong>determine energy performance indicators</strong> (EnPIs) that can track energy performance of the plant.<br><strong><br></strong></li><li><strong>Identifying and prioritising energy saving opportunity (ESO) projects</strong> that can be implemented to improve the energy performance of the plant going forward.<br></li></ul><ul><li><strong>Project plans</strong> focussing on energy efficiency improvements to the Bellville WWTP had to be compiled which incorporated both energy efficiency measures  already incorporated into existing upgrades and also quick low-cost measures which were implemented to demonstrate continuous improvement in reducing energy consumption.<br> <br></li></ul></span><span><figure class="subtopic-fullsize-img"><img src="" class="responsive" alt="" style="width:948px;" /> </figure>​</span><span><br></span><p><strong>Key operation changes to improve energy-efficiency include:</strong></p><ul><li><strong>Constructing three primary settling tanks</strong> (PSTs) to reduce the solids loading and the Chemical Oxygen Demand (COD) of the wastewater before its treated in the Diffused Aeration reactors. This results in at least 35% reduction of COD which means lower airflow is required into the reactors, which results in lower energy consumption. As a result, expanding the Diffuse Aeration reactors can be deferred because its capacity is better utilised for efficiency improvement.<br><br><span style="text-decoration:line-through;"> </span></li><li><strong>Replacing ageing blowers with modern energy-efficient units.</strong> A new air distribution system with fine bubble diffusers in the three reactors will also be installed with automated dissolved oxygen control. The reactors will be rebuilt to be able to perform full biological nutrient removal, and the new reactor zone configuration with larger anaerobic and anoxic zones will be more energy-efficient.<br></li></ul><p>'A third of the City of Cape Town's municipal electricity consumption is from running wastewater treatment plants. If this could be reduced by 10%, it would result in emission reductions equivalent to 13 000 tons of CO<sup>2 </sup>a year. The Water and Sanitation directorate will continue to invest and enhance energy efficiency and treatment processes of our other plants at Macassar, Wesfleur, Cape Flats, Kraaifontein and Potsdam WWTPs.</p><p> 'Thank you to all our staff who are at the forefront of energy-efficiency innovations for wastewater treatment works in our country. The staff of Bellville WWTP can be justifiably proud of achieving this certification. This will not only lead to a greener Cape Town, but also to a greener South Africa,' said Councillor Mbandezi.</p><p> <strong>End</strong></p><p><br></p>2022-11-09T22:00:00ZGP0|#1d539e44-7c8c-4646-887d-386dc1d95d70;L0|#01d539e44-7c8c-4646-887d-386dc1d95d70|City news;GTSet|#62efe227-07aa-45e7-944c-ceebacca891dGP0|#e461c33b-5a6b-427b-aab7-ae593fa11e6d;L0|#0e461c33b-5a6b-427b-aab7-ae593fa11e6d|awards;GTSet|#2e3de6c1-9951-4747-8f53-470629a399bb;GP0|#a3ac5825-3464-4e1b-a58b-75c8b257d806;L0|#0a3ac5825-3464-4e1b-a58b-75c8b257d806|water & sanitation10


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