Chaitanya “Chatty” Sakhalkar
- Jun 12, 2023
- 3 min read

Green—and Smart—By Design

True secondary containment and onboard bearing-wear monitoring make canned-motor pumps the preferred choice where sealless pumps are required.

With the goal to combat climate change through feedstock selection and process technologies that would eliminate greenhouse-gas (GHG) emissions, the renewable bioeconomy—which includes sustainable aviation fuel (SAF), renewable diesel, green crude, biodiesel, ethanol, and finished biobased chemicals—is using carbon intensity (CI) as a metric to measure its operations.

While the big focus continues to be the feedstock, plant personnel are being challenged to identify more ways to contribute to lowering the CI of plant operations. Consistent with this effort, essential process centrifugal pumps are at the forefront of these low-carbon initiatives.

Given the emissions and possible leaks associated with mechanical shaft seals, bioeconomy industry leaders are pursuing sealless pump technology. By design, sealless pumps eliminate any potential of operating emissions and liquid leaks, making the technology an ideal choice for sustainable and environmentally conscious companies.

Within the realm of sealless pumps, canned-motor pumps are often preferred over magnetically coupled solutions due to standard advantages of true secondary containment as well onboard bearing-wear monitoring. Magnetically coupled pumps are equipped with a single containment shell that eliminates operating emissions and leaks normally associated with mechanical seals.

However, in specifying canned-motor pumps, where true secondary containment is provided as standard design, plant operators can rest assured that process fluid cannot leak into the atmosphere—even under upset scenarios.

Further, with technology to monitor bearing wear, canned-motor pump technology offers the only pumping solution that provides real-time measurement of the actual condition of pump-wear components, as opposed to symptoms of wear, which can be inferred from fluctuating power or rises in circulated liquid temperature.

These two features—true secondary containment and onboard bearing-wear monitoring—allow the plants to manage risk and trend wear patterns to establish preventative maintenance schedules with the longest mean time between maintenance (MTBM) intervals, as well as avoid unplanned shutdowns due to pump failures.

In biorefining services, canned-motor pumps are being used in various inside battery limit (ISBL) and outside battery limit (OSBL) applications. Traditional refinery and chemical processing industry operators have invoked ASME B73 for OSBL services and API 685 for ISBL services. Bioeconomy projects follow a similar approach. The application of canned-motor pumps, however, has been broadened within the biobased industry, and they are now being used on highly critical services such as hydrodeoxygenation as well as simpler services in water-treatment facilities.

A variety of features and enhancements are available that provide the opportunity to monitor critical operating parameters required for the handling of volatile, toxic and environmentally sensitive liquids and minimize maintenance exposure. These include:

Rotating element position and bearing-wear monitors with control outputs

Variable frequency drive (VFD) speed-control capability for enhanced process control

Secondary-containment leak monitors

Elimination of alignment

Underwriters certification for hazardous-area classifications

Versatile and space-saving mounting arrangements with small footprints

Full compliance to industry design standards such as API, ISO and ASME/ANSI

High-temperature motor-insulation systems that eliminate cooling-water needs

API 685 Annex D and ASME/ANSI B73.3 circulation systems to meet all fluid characteristics

The global Teikoku Group is the world’s largest manufacturer of sealless, emission-free, canned motor process centrifugal pumps. With manufacturing and design capability in the U.S., China, India and Japan, and subsidiary offices and service centers located in major markets worldwide, Teikoku is positioned to exceed user expectations in both production and support of its pumping technology.