For land-based power generation operators – plants, stations, refineries – redundancy in water treatment is critical. Where seawater is required, effective processing and marine growth prevention Systems (MGPS) play a vital role in protecting plant assets, so preventing downtime is vital. In this second blog focused on the power sector, Darren Dale, Global Product Director at Evoqua Water Technologies discusses the N+1 philosophy as an effective way to minimise risk of plant downtime through system redundancy, and its importance to minimise fixed operating costs in a sustainable way.

With energy prices in many parts of the world at long-term highs, maintaining process uptime is critical to meeting customer demand and maximising all commercial opportunities. By focussing on reliability and selecting the right system, plants can avoid costly downtime and keep their water treatment systems – and, therefore, facility – operational at all times. The best way to boost reliability and resilience? Build in redundancy.

Here at Evoqua, we refer to N+1 as modular redundancy – a way to ensure there is a redundant stream available while running at full capacity. Time and again, this has shown to be a less expensive and more competitive way of operating water treatment within the power sector. It is something many of our clients are now requesting at specification stage, and, indeed, should be a consideration for all those interested in operating MGPS technology and our Chloropac® system.

Let’s take it back to fundamentals. Seawater naturally contains high levels of bacteria and microbes that can cause substantial corrosion, known as microbial induced corrosion (MIC), and build-up in the system, which can lead to extensive asset damage and downtime. Protecting against biofilm, acid-producing bacteria and general bacteria removal can not only reduce unplanned downtime but can also help to reduce operational expenditure.

Industry-leading disinfection technology

Evoqua’s industry-leading technology, the Chloropac® system has been trusted around the world to deliver effective, safe and precise disinfection for more than 35 years. Producing a dilute solution of sodium hypochlorite for direct injection to the treatment stream, the Chloropac system is able to prevent marine growth without the requirement to purchase, store or handle dangerous chemicals on-site.

Chloropac, inherent redundancy and N+1

Our Chloropac systems are a patented* design that utilise concentric tube electrolysis (CTE) cells. Each system utilises multiple cells in each electrolyser and can be scaled to requirements, this means that redundancy is already integrated into the design. If one cell begins to drop in output or is due for replacement, the other cells in each electrolyser can maintain continuous output until the system is serviced. Monitors on each cell pinpoint the cell quickly. The cell design also means that a cell swap out takes only 30-60 minutes and can be done onsite by a trained operative. When compared to alternative MGPS technologies, like flat plate, a single Chloropac electrolyser is equivalent to using a pair of 100% flat plate units.

For larger plants, we offer N+1 systems for ultimate peace of mind. This means ‘N’ number of electrolysers are sized for 100% of duty with one (1) redundant electrolyser.   Combined with the integrated cell redundancy in each electrolyser, the overall installed catalyst area is reduced when compared to a more conventional approach of adding full stream redundancy, e.g. 3 x 50% or 4 x 33% streams, up to 30% less, saving on the total cost of ownership through the life of the plant. This has the added benefit of minimising the use of a precious resource, the catalyst materials, helping us in our common journey to sustainable energy transition.

As the energy market reaches new peaks, ensure that your plant is able to meet consumer demand and maximise its competitiveness, by minimising downtime with the help of effective MGP and disinfection. The Chloropac system is an industry-proven solution that offers cost effective redundancy options, in a compact footprint, offering excellent service life and with zero requirement to handle or store harmful chemicals.

*patented in some countries