The world’s largest thickeners include our Dorr-Oliver brand and our sedimentation equipment is used around the world - recognized as the leader in mining thickening applications such as concentrate, tailings, preleach and CCD.


Dorr-Oliver and WEMCO flotation technology provides either naturally aspirated or forced-air flotation, using a universal tank design which creates greater flexibility and more control over coarse and fine particles for maximum recovery.

mixedROW flotation system

Industrial pumps

Our Dorr-Oliver ODS® and Gorator® pumps are rugged and durable, able to handle heavy slurries, or even extremely corrosive or abrasive materials. Our ODS Diaphragm Pump design is the result of decades of experience in slurry and sludge-handling technology. Our Gorator pump is used in pulp and paper mills, industrial water, chemical processing, and food waste processing.

A brief history of Dorr-Oliver

The Dorr-Oliver brand has a history stretching back almost a hundred years to a time when Dorr and Oliver were two separate companies.

Founded in 1904, the Dorr Company’s initial focus was on solving processing difficulties in gold milling, but they quickly expanded into other industries on the back of successful innovations such as the reciprocating rake classifier, continuous processing thickener and agitator.

The Oliver company followed a very similar path. Founded in 1907, their first widely successful invention was the continuous vacuum filter, designed to separate leached slimes from gold bearing cyanide solution. Like the Dorr company, they quickly moved into other industries, continuing to build on their success.

By the middle of the century, it was clear the two companies were aligned in their solutions, industries served and marketing philosophies; Dorr-Oliver was formed. Further M&A activity increased the company’s scope both geographically and in expertise. After multiple changes in ownership and structure, Dorr-Oliver became part of FLSmidth in 2007 with the acquisition of Dorr-Oliver, EIMCO, WEMCO and KREBS® Engineers from Groupe Laperrière & Verreault Inc. (GL&V).

Today, Dorr-Oliver’s long legacy is upheld with the continued sale and development of our filter, flotation and pump products for industries including minerals processing, industrial wastewater, chemicals processing, pulp and paper, food processing and more.

Stories from FLSmidth