Emerson Industrial Automation
Newsfront
TAMING THE CPI’S ENERGY BEAST Motors are notorious energy users, but advanced motor and drive technologies can help increase efficiency in the plant hether for pumping, mixing, compression or ventilation, motors are used everywhere in the chemical process industries (CPI). Unfortunately, they are notoriously energy intensive, accounting for about 65% of the electrical consumption of a chemical production site. However, with the world, especially the U.S. and Europe, turning a watchful eye on energy consumption, motor and drive manufacturers are developing newer, highly efficient motors, optimized systems and smarter drives that can help tame the proverbial energy beast, leading to potentially significant savings. “We are finding that improvements in the efficiency of fixed-speed motors allow a reduction of approximately 10% of the electrical energy consumption of a site, while the use of variable speed generally allows savings of over 30% to be made on the drive system concerned,” says Pascal Galant, president of sales and services for drives and motors with LeroySomer (Angouleme, France; www. leroy-somer.com), a business unit of Emerson Industrial Automation. Among the latest offerings, according to Galant, are induction motors with IE2 or IE3 efficiency levels that can be used in conjunction with very low-loss gearboxes. For variable speed, motors specifically designed for operation on variable speed drives provide solutions for process require-
W
ments such as high efficiencies and operation at constant torque. And innovations including permanent magnets are also becoming more widely available. These technologies are making it possible to find the energy reductions Baldor stated above.
FIGURE 1. The Dyneo LSRPM permanent-magnet synchronous motor’s patented technology allows a significant increase in efficiency, particularly in machines that operate with a variable load
FIGURE 2. Baldor offers the power dense, energy efficient technology of the RPM AC motor with permanentmagnet rotor technology to provide a direct drive motor for cooling tower applications
Motor
Advanced motors For example, Leroy-Somer offers its Dyneo variable speed drive units, such as the LSRPM permanent-magnet synchronous motor (Figure 1). The LSRPM has the benefit of the mechanical construction of an induction motor, making it particularly suitable in harsh environments. But by eliminating rotor losses, the patented technology of the radial permanentmagnet rotor allows a very significant increase in the efficiency of the machines, in particular those that operate with a highly variable load. The company says it has measured additional energy savings of over 10% compared with traditional variablespeed solutions (IE2 induction motors controlled by a variable speed drive). Baldor Electric Co. (Ft. Smith, Ark.; www.baldor.com), a member of the ABB Group, is offering a cooling-tower direct-drive, permanent-magnet motor and variable-speed drive as a more energy efficient replacement for conventional mechanical-gear reduction
designs. The cooling-tower drive controller and RPMAC permanentmagnet motors (Figure 2) are designed to drop directly into existing gearboxmounting patterns. One of the biggest benefits of a retrofit is the improvement to the fan-drive-system efficiency via the elimination of the gearbox from the system and the addition of the adjustable-speed drive. Permanent-magnet motors greatly increase operating efficiencies, even under lightly loaded conditions that are typical in fan applications at low speeds. Temperature rise in the motor is also considerably lower, making for a power-dense package and increased motor life over conventional motor systems. And, Hagglunds (Mellansel, Sweden; www.hagglunds.com), a division of Bosch Rexroth AG (Lohr, Germany), offers its CBM direct drive motor to help processors do more with less energy and resources, says Ashok Amin, mining and material handling manager in the Americas with Hagglands. The
CHEMICAL ENGINEERING WWW.CHE.COM FEBRUARY 2013
23