How is FSA working to improve Energy Efficiency of Sealing Systems?
FSA members have been working to improve sealing technology steadily and this has had two major beneficial side effects for the industry. The first one has been to reduce fugitive emissions from industrial processes. As hazardous or toxic chemicals are more effectively contained, there has been a reduction in the risk of pollution of the air and water sources surrounding heavy industrial activity. The other major side benefit has been a decrease in the power consumed by sealing systems, either directly or indirectly. Seals are not generally seen as being a significant source of power consumption, yet it has been shown that some pump sealing systems can actually consume more power than the pump motor. As sealing technology has improved over the last few decades, more efficient systems have been devised and put in place to significantly contribute to energy savings.
In addition to individual members’ contributions, there has been another aspect of the improvement which has occurred through the interaction of manufacturers within the Fluid Sealing Association. There has also been a significant cooperation with the European Sealing Association to increase the reach of the efforts of both associations.
As a group, the manufacturers have been able to develop and conduct many educational programs on the correct use of their products. The curriculum is generic and geared so that users can properly obtain all the benefits that the sealing products can provide. Indeed the proper selection, application, and installation of sealing devices are essential in being able to achieve the maximum reliability and life. Sealing products are sensitive to installation and operation, and instructing users on how to use the products to gain maximum life has been a major contribution that has been done as an organization. Indeed, Mean Time Between Repair, (MTBR), has steadily increased in the recent past, and this has been in part due to the educational efforts conducted by its members individually and by the FSA as a group. Keeping plants running and operational increases their productivity and helps reduce the extra power consumption incurred during equipment stops and starts.
How will improving Sealing Systems Efficiency help Pumping Systems?
The first direct improvement in efficiency is simply in containing the process. Any reduction in leakage of a process results in overall plant efficiency by increasing its productivity. Surprisingly the amount of lost product can be a percentage of production, and therefore any reduction in leakage increases output without any increase in the amount of energy required.
Systems contain product but can also contain energy. In a power plant, for example, water is used as a medium and not as output. Electrical energy is the output. Yet water used as boiler feed, steam or condensate is at a temperature far above ambient and energy is required to bring the water to these higher energy states. Thus any leakage of hot water or steam that must be replaced requires extra energy and thus reduced the plant efficiency.
For dynamic seals such as compression packing or mechanical seals there is also direct power consumption. As surfaces are in contact in relative motion and under substantial loads, there is frictional heat generated. New materials are used in compression packing that are PTFE and carbon or graphite based with much reduced coefficient of friction and therefore reduced power consumption. For mechanical seals hydraulically balanced designs have replaced unbalanced ones, and gas lubricated non contacting seals have been adapted to pump service, with much reduced or negligible heat generation. The judicious use of face material, such as silicon carbide against silicon carbide, can eliminate the need for an external flush in many processes where solids are present in the pumped fluid. Removing the liquid introduced at the seal needs, in many cases, to be removed, and this can be extremely energy intensive in processes where it needs to be evaporated. Similarly, using seals with material able to operate in elevated temperatures reduce or eliminate the requirement to cool the seals and therefore the process which must then be reheated to maintain system integrity. The judicious use of seal design and material can therefore significantly increase the efficiency of sealing systems.
Have you seen any improvements? What is the next step?
There have been many improvements in the reliability of sealing systems and in the reduction of their energy footprint. In general, increased reliability goes hand in hand with reduced power consumption. Although the systems may require an increased initial cost, their life cycle cost ends up being substantially lower through energy savings and reduced maintenance. The MTBR in many industries are no longer determined in months but in years. Some seal have been known to operate for more than a decade. The mechanical seal standard ISO 21049, API 682, has set as a goal a minimum of three year continuous service. Members of the FSA and ESA have contributed to this extensive standard which includes many tutorials and explanations as well as specifications. A new extensively updated and expanded edition is in the final stages of the approval process.
Course material specifically dedicated to reducing the energy consumption of sealing systems has been developed by the FSA and will be first delivered at the upcoming International Pump Users Symposium in Houston. The delivery of educational material is changing as well, from the traditional format of one day classes at an industry gathering to online teaching courses.
The Department of Energy is working on establishing Regulations for industrial pump systems efficiency, and the FSA in collaboration with the Hydraulic Institute is supplying technical information to regulators in order to insure the maximum effectiveness from the upcoming regulatory mandate.
The expectation for seal reliability and extended life of sealing systems has greatly increased and continues to increase. A sealing expert once said that the successes of yesterday are the standard of today, and the failures of tomorrow. The Fluid Sealing Association and its members are working to make this a continuing reality.
For more information, visit www.fluidsealing.com