Twelve Milton Roy dosing pumps are being installed at petrochemicals producer Sasol Synfuels’ water recovery growth project, in Secunda.

Germiston-based pumps company Ecochem Pumps signed a contract with Germany-based engineering company ThyssenKruppe in September last year to supply the chemical-dosing pump models from pumps manufacturer Milton Roy’s Maxroy, mRoy and Prime Roy ranges.

“The pumps are used for chemical injection to automatically dose the correct amount of chemicals into the system,” says Ecochem pumps MD Ed Lemke.

He notes that Milton Roy is the largest dosing-pump company in the world and Ecochem Pumps has the complete Milton Roy range, which consists of a utility water-treatment, light-duty range of pumps and a heavy-duty industrial range of pumps.

“We supply both types of pumps to general industry and oil refineries across the country,” he states.

The Sasol Synfuels water recovery growth project entails the treatment of water effluent from the refinery reactors using a process in which alcohols, ketones and other usable chemicals are removed, while the remaining acid- containing waste water is treated at a biological plant.

The Sasol Synfuels water recovery growth project started in late 2010.

Ecochem Pumps sales engineer Darren Cox says the Milton Roy dosing pumps are the product of choice for oil refineries throughout Southern Africa.

“The dosing pump is a reliable, long- lasting API 675-compliant product, with a low overall cost of ownership. Ecochem Pumps has old pumps at refine- ries throughout the country that are still functioning after 30 years plus, owing to their robust construction and superior technology and the relatively small number of moving parts in the design,” he says.

Cox notes that the largest pumps ordered for Sasol Synfuels will deliver dosing capacities of up to 2 500 ℓ/h.

The dosing pumps are the hydraulically actuated diaphragm type, which come from the heavy-duty range.

“This type of mechanism results in a dosing flow rate that is accurate to about 1% as per API 675 requirements. The stroke control knob can be adjusted from zero to 100% while running,” he says.

The pumps for Sasol feature a double diaphragm with a rupture-detection mechanism that provides increased safety and operational redundancy, while also enabling sufficient time to plan for rupture repairs should they occur on the ruptured diaphragm, with- out pump downtime.

“If the process diaphragm is per- forated, the rupture is immediately indicated by a pressure gauge installed on the liquid end,” he points out.

Lemke states that Milton Roy was the original inventor of the hydrauli- cally actuated dosing pump and that the API 675 specification was set around the company’s dosing pumps in the 1940s.

“These are now the standard dosing pumps used at oil refineries globally,” he notes.

“Our record shows the industry that we are at the forefront of development when it comes to supplying pumps for oil refineries. “We are a reliable and user-friendly company because we have a range of products, good engineering support and sufficient spares that are readily available,” Lemke points out.

He explains that it is important to have a variety of spares on hand and for many pumps manufacturing companies to support the large number of pumps throughout the southern hemis- phere.

“A refinery wants to be assured that a company has spares available and because we support such a large industry, we must have spares available on the shelf,” concludes Lemke.