Construction World July 2016

WATER ENGINEERING

SUSTAINABLE WASTEWATER treatment in Gauteng Following on the continued success of Royal

energy consumption. Bert Bakker, Water Advi- sory Director at Royal HaskoningDHV states, “Not only is the capital outlay for Nereda® plants much cheaper but one has to take into account life cycle costs which for a waste- water treatment plant is typically 30 years. These savings are substantial if one considers the energy saving, operational cost savings and reduced maintenance costs while providing better effluent quality.” Royal HaskoningDHV provides technical support with experts on hand who can log in remotely to support the on-site maintenance team. Nereda® is run via Royal Haskoning- DHV’s Aquasuite® Control Software range based on real time data and predictive algo- rithms that can predict 48 hours in advance and adjust systems accordingly to maximise system efficiency. Aquasuite® brings intelligent solutions for the entire water chain, solid model- based forecasting and controlling software to enhance the operational performance of water systems and maximise the potential of assets. “A key feature of the Nereda® Controller software is its predictive ability. This soft- ware is constantly gathering data from the operations in order to be able to think ahead and tell the operator when to adjust the system for various changes in flow etc. What this means is that your plant will always be running at its most efficient because you always know what to expect so you can prepare well in advance,” explains Bakker. About Nereda® Nereda is the biological wastewater treatment technology that purifies water based on bacteria growing into compact granules. The technology was invented by the Delft University of Technology in the Netherlands and developed in a unique public-private partnership between the University, the Dutch Foundation for Applied Water Research (STOWA), the Dutch Water Authorities and Royal HaskoningDHV. Currently there are 15 plants in operation and another 15 under construction or design worldwide.

HaskoningDHV’s ground-breaking Nereda® Waste Water Treatment technology, in operation in the Western Cape as well as a number of countries worldwide, East Rand Water Care Company (ERWAT) has awarded a contract for the design and build of a Nereda® plant in Gauteng.

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constraints, to stricter effluent requirements and these challenges are exacerbated by budgetary constraints. Robertson argued that sustainability requirements are driving technological advancement and innovation and that the advantage of Nereda® in comparison to acti- vated sludge systems ultimately translates into more sustainable and cost effective wastewater treatment. There are a number of fully operational Nereda® wastewater treatment plants across the world with two fully operational sites in the Western Cape – Gansbaai, operational since 2009 and Wemmershoek, operational since 2015 Both plants operate in a footprint much smaller than conventional activated sludge systems. Nereda® plants typically achieve a foot- print reduction of 50 to 75% when compared to similarly loaded activated sludge plants. In addition to this Nereda plants are much more energy efficient and can save up to 50% on

The contract awarded to WEC Projects, with Royal HaskoningDHV the technology supplier, is at the Hartebeesfontein Wastewater

Treatment plant. The project aims to improve the capacity of the plant by 5 Mℓ/ day using existing infrastructure. Nereda® technology is ideally suited to areas where there are budget constraints, space is at a premium, energy saving is critical and there are strict effluent and environmental sustain- ability requirements. In a paper presented at the Water Institute of South Africa (WISA) Confer- ence held at the ICC in Durban during May, Struan Robertson from Royal HaskoningDHV stated that a shift away from ‘activated sludge approach’ towards ‘aerobic granular approach’ would assist in addressing the challenges facing the wastewater treatment industry in South Africa. The South African wastewater treatment industry is facing numerous challenges ranging from energy

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CONSTRUCTION WORLD JULY 2016