Mechanical seals, pumps and complementary pumps products supplier Mechanical Rotating Solutions (MRS) partnered with international pumps company HCP Pumps to supply axial flow pumps to service the recirculated aquaculture system (RAS) of an aquaculture farm in the Eastern Cape.

The project, completed in July, required the augmenting of the RAS with the correct equipment, which MRS CEO Franscois Steenkamp says enables the system to control the overall environment and ensure optimum water quality and temperature, consequently guaranteeing optimal, sustainable fish farming.

The RAS is a land-based unit that circulates, cleans and recycles saltwater, with the least possible volume of water used while avoiding spills and pollution.

“The recirculation of the water means that pumps are the most crucial element in the aquaculture system. “Considerable thought goes into selecting suitable pumps to work in this specific environment. “This project called for the use of axial flow propeller pumps together with centrifugal pumps and single-stage, end-suction pumps,” explains HCP Pumps South Africa MD Gerhard Swart.

The design of the RAS required that the pumps ensure an effective volume and constant flow of water through the system to mimic a natural environment for the fish.

Steenkamp explains that the movement of water ensures that particles and sediment introduced during feeding does not settle at the bottom of the tank system, with strong flow also forcing a particular swimming behaviour onto the fish in the system, further mimicking a natural environment.

Hence, HCP chose to implement its L-series of axial flow pumps. These large- volume transfer pumps are ideal for flood control, irrigation out of canals and for water supply or drainage in agriculture and aquaculture applications.

These pumps can move 5 500 ℓ/min at a 4 m head, consequently ensuring optimal flood control for this specific application.

Further, owing to the corrosive effects of saltwater, MRS coated the wet-ends of the pumps with the Belzona 5811 immersion-grade epoxy coating to extend the life of the new pumps.

The two-part epoxy coating protects immersed equipment in aqueous solutions of up to 50 º from the effects of corrosion caused by chemicals, sea water and crude oil.

This solvent-free coating is suited to any metallic and nonmetallic surface, with maintenance further simplified through its being applied by brush or sprayed, and cured at room temperature without the need for hot work.

“By augmenting the HCP pump range with specialist products offered by MRS, clients are assured of the best solution possible. Over the past decade, we have combined HCP’s pump offering and MRS’ Belzona-engineered coatings to prevent severe cavitation and corrosion,” adds Steenkamp.

Other Projects

MRS replaced the gland packing of a pump in August at the tailings facility of a mine, in Mpumalanga, this year.

Steenkamp explains that, because the pump consumed large volumes of water, the original gland packing was replaced with an AESSEAL CDPH mechanical seal, complemented by a SW02 water management system.

An AESSEAL double seal and tank support system – which recirculates the water instead of flushing it to drain or adding it to the slurry – eliminate wasted water.

Meanwhile, MRS has noted an uptick in demand in Africa for its Straub pipe couplings over the past six months; the couplings are being used in more than 40-million pipe connections globally.

There has been a recent increase in orders from mining industries in the Democratic Republic of Congo (DRC) and Zambia.

Steenkamp adds that, with the DRC being considered “wealthy” with regard to its natural resources, MRS expanded its business footprint into the DRC and Zambia.

He explains that these countries, collectively, contain over 70% of the world’s cobalt reserves, as well as abundant natural resources such as copper, silver, uranium, lead, coal, zinc and gold.

“By joining new African partners, MRS will have a local footprint offering in these countries that will encompass the complete range of Straub pipe couplings. “Our new venture will ensure that we have the right coupling available.

“This will, consequently, allow for pipe connections of practically all conceivable pipe diameters for the same or different types of pipe materials, various media and temperatures, as well as for a range of the operating pressure values,” Steenkamp concludes.