What are the energy and water usage impacts of these systems?
by Jason Ferris

The markets for pumping systems are seeing an ever-increasing focus on energy efficiency in an effort to reduce carbon emissions, resource usage and costs of operation. Industrial pump system users have heightened their focus on efficiency initiatives as natural resource and raw material usage costs increase. External drivers include the U.S. Department of Energy (DOE), which has highlighted data showing that pump systems represent approximately 6 percent of the total U.S. industrial energy consumption.

Plant Water Usage
When assessing the overall operating efficiency of plants, water usage can become a significant energy cost of its own. Water is commonly used as a primary system in power cycles. It is also used as a secondary system for cooling, dilution or cleaning. Closed-loop water systems require pumps, cooling towers and makeup water treatment systems that can consume significant electrical and thermal energy. Open-loop systems also require effluent treatment before returning the water to its source. Efforts to reduce water use and the associated energy costs are often a component of industrial plant best practices for efficiency improvement.

Pump Systems
Significant opportunities for improvement exist for energy and water use reductions in pump systems. Pumps are often operated at suboptimal flow and head, significantly decreasing efficiency. The Hydraulic Institute (HI) introduced the educational initiative “Pump Systems Matter” to help increase focus on this opportunity.

Certain types of sealing systems can have a large impact not only on energy but water usage as well. In some cases, the combined power use can equal or exceed that of the pump driver. The opportunities to reduce energy usage in sealing systems can be far greater than those achieved by correcting pump efficiency issues.

Life-Cycle Cost Tool
The Fluid Sealing Association (FSA) and the European Sealing Association (ESA) have produced a seal life-cycle cost calculator tool that estimates the relative energy consumption of different sealing system configurations. This tool can be used to help customers identify the most efficient system option for their applications.

ISO Assessment Standard
In addition to FSA’s calculator tool, draft Standard pr ISO 14414, “Energy Assessment for Pumping Systems,” has been released for comment in 2013. The draft contains an annex that provides simplified guidance on selecting sealing systems based on energy and water efficiency considerations. Figure 1 provides a quick reference to the thermal, water and electrical efficiencies of different seal arrangements and their supporting API piping plans. This figure is based on Table B.4 in Annex B of the ISO draft with permission from ISO. This “Sealing Sense” will provide an overview of the contents of this table, with examples of selected inefficient API piping plans and their energy and water usage impacts, along with alternatives to those plans.