Creative new impeller design keeps latex flowing

Edited by the Processingtalk editorial team Jan 23, 2007

Amarinth has designed and commissioned an innovative pumping solution for Polimeri Europa which prevents the frequent clogging common when moving latex agglomerate around a plant

Amarinth has designed and commissioned an innovative pumping solution for Polimeri Europa which prevents the frequent clogging inherent in the existing centrifugal pumps used to move latex agglomerate around the plant.

The new pumps have increased reliability by a factor of 15, delivering a return on investment in just nine months.

Polimeri Europa is one of the major world producers of elastomers at their plants in Hythe and Grangemouth, United Kingdom.

Using a range of proprietary technologies and state-of-the-art production systems, the company produces basic chemicals, polyethylene, elastomers and styrenics for many of the world's leading brands.

For years, the latex agglomerate used during production had tended to clog and accumulate behind the impellers of the existing centrifugal pumps.

This overloaded the pumps causing gland leakage.

Despite a regular maintenance schedule of stripping, cleaning and rebuilding the pumps and re-packing the glands, seizures would still occur each week, sometimes resulting in the failure of a shaft or bearings.

The consequence was unplanned downtime and disruption to critical stages of the production process.

Polimeri Europa was unable to identify any standard products that would meet their needs and so it invited a number of ISO9001 accredited pump suppliers with proven track records to propose how they could resolve the problem.

The design parameters were for a pump that could run for three weeks before requiring any maintenance.

Amarinth were selected for their ability and willingness to work with Polimeri Europa on optimising a design which would include special features outside their standard catalogue.

The base pump chosen was an N-Series which included a removable front suction cover enabling quick access for cleaning.

A scalloped impeller was specifically designed to minimise clogging and an electro-polish was applied to the back-plate and impeller to create low cohesion surfaces.

Finally, working in partnership with John Crane, a special mechanical seal was designed to contain the latex agglomerate.

The new pumps were delivered on-time and have exceeded the design expectations on this very demanding application.

Reliability has improved by a factor of 15 and a quick internal jet-wash is all that is often needed.

Previous pumps required cleaning and re-packing every few days, or even daily during difficult running conditions, a process that took 6 - 8 man hours for each pump.

The resultant cost savings in parts and labour mean that the pumps will pay for themselves in just nine months.

Polimeri Europa are delighted with the results and has now brought additional pumps on-line: they are working with Amarinth to enhance the existing pumping solutions in other applications.

Robert Pearce, Project Manager at Polimeri Europa, summed up his satisfaction: "We are delighted with the original thinking and design work undertaken by Amarinth in developing a pump tailored to our demanding application.

They have successfully overcome the issues we have faced for the last 20 years of clogging when pumping our latex agglomerate.

These new pumps were delivered on-time and have performed to specification, leading to a significant reduction in maintenance costs and eliminating expensive and disruptive unscheduled stoppages".