Abundant water reuse opportunities in South Africa

ABUNDANT WATER REUSE OPPORTUNITIES IN SOUTH AFRICA

There is no single, specific technology for water reuse

While there is extensive scope to expand water reuse in South Africa, it is by no means a new concept for the country. In 2001, a water recycling project was commissioned in KwaZulu-Natal where Veolia was awarded a 20-year operations and maintenance contract.

We have recently submitted a tender for another 20year concession. Presently, the plant treats domestic and industrial wastewater to near potable standards for sale to industrial customers for direct use in their processes. The new tender includes the additional supply of potable water for the local community,” says Miles Murray, director: Business Development, Veolia Services Southern Africa.

Currently, the plant features Veolia technologies such as the Multiflo clarifier and Hydrex water treatment chemicals. Multiflo offers an efficient process for removing total suspended solids (TSS), colour, algae and heavy metal co-precipitates. It can also be used in the softening process, as well as the polishing process to remove pesticides, organic matter and new emerging pollutants. Hydrex water treatment chemicals protect water treatment systems against scale deposition, corrosion, fouling and biological problems.

Over the past 20 years, Veolia has been responsible for the plant’s wastewater catchment, conveyance, trade effluent control, preliminary and primary treatment, secondary and tertiary treatment, reclaimed water reticulation and utilisation.

It is South Africa’s first water reuse plant, one of the first water-related public-private partnerships (PPPs) of its kind, and the first to adopt a new contractual model for financing new infrastructure. The project is managed under a build-own-operate-transfer (BOOT) model.

The total cost of the project (construction for the new tertiary plant, purchase and upgrade of the municipal utility assets used for the project, and piping system) was around R72 million. Veolia, together with other partners, provided all

Miles Murray, director: Business Development, Veolia Services Southern Africa

Martin Kotze, project development manager, Veolia Services Southern Africa

the funding needed for the project. Veolia shoulders the risks of meeting the water quality needs by the two industrial users. Therefore, the municipal utility has not incurred any extra capital cost for the taxpayers.

The plant pays the municipal utility an annual management fee and a fee for the lease of the land, as well as a levy per cubic metre to reflect the cross-subsidisation income from the industrial users – who have signed water purchase agreements.

The private industries using the water benefit from a saving of 52% in water tariffs by reducing the amount of potable municipal water consumed; the municipality and the local community benefit from the freeing up of scarce potable resources for human use; and the environment benefits from a 10% reduction of wastewater discharged into the ocean, mitigating pollution impacts.

Practical considerations “These types of projects can take close to a year to create a concession agreement and fine-tune the financial modelling. Then the plant almost always needs to be upgraded to achieve water reuse. A company will recoup the capital investment after a few years, so it is important to take a long-term view when structuring PPPs and BOOT agreements for water reuse,” explains Murray.

Martin Kotze, project development manager at Veolia, adds that extensive water and wastewater sample and collection analysis is a pivotal part of a water reuse plant’s success. “There is little point in investing millions of rand into a plant and only analysing one water and wastewater sample. This does not account for seasonal variability or inconsistencies on certain days of the week. For instance, a factory floor may be washed down with water on a Friday and the factory may only manufacture a certain product on a Sunday. This will all have an impact on wastewater, and it is important to understand these parameters before designing a plant.

“Water treatment cannot be an afterthought. There needs to be adequate space to build a plant as well as space for maintenance (removing pumps). There also needs to be adequate time to build a plant,” he says.

Water reuse technologies There is no single, specific technology for water reuse. Water reuse involves several processes/technologies (like clarification, reverse osmosis, evaporation and chemical treatment); the combination of which is customised to suit each individual case’s requirements.

“The municipal water treatment market mostly uses standard primary and secondary treatment with large basins, clarifiers and a membrane plant, with either ultrafiltration, ultraviolet purifier or advanced oxidisation at the end,” adds Kotze.

According to Kotze, mine water and wastewater treatment solutions from Veolia help mining companies reduce their effects on the environment with economical mine process water and wastewater treatment technologies.

At a gold mine in South Africa, Veolia supplied mine water treatment boilers for metallurgical operations. The mining company’s site is also maintained with chemicals and technical support from Veolia, where acid mine water was affecting the environment and surrounding communities.

There is another water reuse plant near Jeffreys Bay where the wastewater contains organic matter from milk, yoghurt and cheese residues. The aim

Veolia is well established in Southern Africa, with water reuse plants in both Namibia and Botswana Reverse osmosis membrane trains

Veolia can help companies comply with zero effluent discharge standards

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is to reuse the treated water for non-food production applications, such as cooling, garden watering and cleaning. The facility includes an acidification tank, anaerobic digester, ultrafiltration and reverse osmosis skids, as well as a biogas boiler.

Orion purified water technology is used for water reuse at a pharmaceutical company in Port Elizabeth. It offers softening, reverse osmosis and continuous electrodeionisation technologies that can be fully or partially hot-water sanitised. Orion can reduce overall water and energy consumption through a reuse cycle and the introduction of more energy-efficient pumps.

Veolia is well established in the Southern African environment, with water reuse plants in both Namibia and Botswana.

The Veolia difference “If reused water is worked back into a production process, it needs to be within certain parameters. Veolia excels at efficiencies across pipelines, reducing downtime and equipment maintenance costs, as well as ensuring that the water is of a consistent quality within the agreed-upon parameters,” says Kotze.

He elaborates that Veolia has the necessary skills and experience and that – as a global company with a 168-year history in the water industry – Veolia technologies are trusted and recognised worldwide. This makes various certification processes a lot easier. “Our strength is that we supply an end-to-end solution. Veolia understands the entire water treatment value chain and we usually do everything in-house. The operation and maintenance of a plant is important to Veolia – we like to take ownership of an entire water treatment project to make sure it works optimally.”

Veolia also has the financial muscle with a strong balance sheet and good credit ratings to finance BOOT projects.

Drivers “Water reuse is increasingly becoming a part of different companies’ sustainability plans. But in South Africa, water security is the primary driver. Manufacturing plants and other businesses cannot afford to come to grinding halt every time a municipality is unable to supply water. The cost of potable water in South Africa, compared to the cost of potable water in Europe, is very cheap. So, while sustainability and water security are drivers for water reuse in South Africa, there is little motivation for cost savings. However, as water becomes increasingly scarce – with growing populations and the economy – and as water pollution intensifies, the cost of water treatment will rise and water reuse will become an obvious choice,” concludes Murray.