What are the advantages of containerised modular systems?
MO: The modular system, as the name implies, is supplied either as prebuilt and package-type plants or built on-site out of concrete (or steel) in such a way that further modules may be added later to cater for increased demand. Being modular, the add-on is far less painful and costly than building extra capacity from scratch.

Why are these systems suited to rural South African and African conditions?
With the pre-built modular plants, the modules are typically predesigned and standard size steel (or GRP) items, like clarifiers and pressure filters, or in the case of smaller modular plants, the whole or part of the plant is housed in a marine container (either 6 or 12 m). This gives the advantage of only requiring the most basic of civil work. Rural plants are typically difficult and expensive to build as they’re inaccessible and out of the range of deliveries of cement, bricks, etc.

What are WPCP’s offerings?
WPCP offers a range of modular/containerised plants from small skid-mounted plants to modular plants that can handle up to 10 Mℓ/d.

What are the most effective applications?
Agricultural villages, small out-of-the-way towns and emergency plants where there is just no timeto wait for the conventional concrete-type plants to be built.

What are the challenges to the roll-out of these systems?
The usual challenges include, but are not limited to: funding and location – the cost of and the sometimes difficult, if not impossible, terrain that needs to be dealt with in getting the equipment to site. Lastly, but most importantly, the running and management, including maintenance of the plant once it has been constructed.

How does WPCP overcome these challenges?
We offer financing, if required, via our partner banks. We also try and employ a plant design that suits the application and terrain. We offer ongoing training and support.

How do these systems compare cost-wise to other options?
The modular, coated steel plants – or GRP/ fibreglass in the case of smaller plants – are a lot cheaper than conventional concrete-type plants. The structures are cheaper and take about a quarter of the time to construct, saving labour and time-related P&G costs.

How technology-intensive are they?
They are fairly technology intensive, but can be made to be mainly manually operated or automatically operated using PLCs, SCADA and telemetry/modem. The choice of technology depends on the client and the infrastructure that they have to both run and maintain the plant. A fully automated, and well maintained, plant will always give better ongoing quality final water than a manually operated plant, especially with changing raw water quality. The opex will be lower but the capex will be quite a lot higher. Obviously one cannot propose a fully automatic PLC-driven plant if there are no suitably trained technicians to repair a defective electric actuator of PLC software, for example

What is WPCP’s focus going forward?
The demand for potable water and purified process water is increasing with the growing population and things like mining infrastructure further north in places like Mozambique, Zambia as well as Central and Western Africa. It is our intention to focus on this, without any detrimental effect on our current South African municipal business.

Any advice for potential clients?
Any water plant requires upfront design based on a number of factors. This includes raw water quality, which needs to be analysed (typically a SANS 241 analysis) over the different seasons chemically and microbiologically. The capacity required should also be considered: What are the current, medium- and longterm capacity requirements? Too many package/modular plants are designed on the basis of “I have a dam and there are 500 people. What will a plant cost?”