Industrial Utility Efficiency    

Technology

The useful and various properties of nitrogen (N2) in industrial applications rank it as one of the most specified gases in industry. For the manufacturer, nitrogen options exist in the choice of delivery system, compliance with clean air standards, safety and purity. In researching these choices, manufacturers can accurately select the optimum nitrogen supply required, often at a considerable savings. Selecting purity levels of 99.99% or higher in many industries and applications ads a variety of costs, both financial and efficiency, which may be needlessly incurred.

Air Compressors

In general, this article focuses on the definitions of terms often used to understand centrifugal air compressor performance. Comments are also made on how to measure power consumption. This article is not intended to be an engineering discussion of the various types and designs of centrifugal and other air compressors.

Air Treatment

Compressed air is dried to prevent condensation and corrosion which can disrupt manufacturing processes and contaminate products. Water is the primary promotor of chemical reactions and physical erosion in compressed air systems. A myriad of desiccant dryer designs have been devised to provide “commercially dry” air, air having a dew point of -40°F or less, to prevent corrosion.  Desiccant dryers use solid adsorbents in granule form to reduce the moisture content of compressed air.

Blowers

High speed bearing technology is applicable for aeration blowers operating at much higher speeds than the typical 60Hz, 3600RPM for cast multistage units. High Speed Turbo (HST) units are usually single stage (though some utilize multiple cores) and rotate from 15,000 to 50,000RPM. At such high speeds, standard roller bearings cannot offer the industry standard L10 bearing life. Two types of bearing technologies have come to dominate the wastewater treatment market for these types of machines: airfoil and magnetically levitated. Often the two technologies are compared as equals, however, in many significant ways they are not.

Compressor Controls

Quite often the typical variability in compressed air flow demand does not proportionately translate into power reductions at the air compressors. This can be a result of numerous problems with the compressed air supply system. It is important to understand the supply-side’s ability to respond to the demand-side of the compressed air system. If the air compressors, on the supply-side, are not able to translate flow reductions into energy savings, implementation of demand reduction projects should be re-evaluated.  

Instrumentation

This article defines different aspects of regulator design and how they affect air wasted by droop. Some ways to reduce droop have be shown and some special case situations discussed. By taking care with regulator selection and installation, regulators can save large amounts of air instead of wasting it.  

Pneumatics

The design of wastewater treatment plants is changing, and it has something to do with LEGO® bricks. More specifically, it has to do with how large and complex LEGO structures are built. If you follow the instructions carefully, you build module after module, eventually piecing them together to create a fully functional and cohesive unit.

Vacuum

It’s one thing to move materials during the production process, but when it’s a finished product on the packaging line, choosing the right material handling system is essential. Getting it wrong results in squandered production time when product loss occurs, and wasted raw materials.

Cooling Systems

As a result of compressed air awareness training and a focus on energy management, two facilities in different parts of the world have reduced their compressed air demand substantially by removing vortex style cabinet coolers from some of their electrical panels and reworking the cooling systems.  These facilities were previously unaware of the high cost of compressed air and how much could be saved if other methods of cooling were used. This article describes some of their efforts in demand reduction.
Compressed air is used in more than 70 percent of all manufacturing activities, ranging from highly critical applications that may impact product quality to general “shop” uses. When compressed air is used in the production of pharmaceuticals, food, beverages, medical devices, and other products, there seems to be confusion on what testing needs to be performed.
In compressed air systems, every adjustment or system modification has consequences, so, before making changes, it’s important to understand how those changes will affect each piece of equipment.  For example, simple things — such as lowering the compressor’s pressure set point, or failing to maintain the compressor’s aftercooler — can result in moisture contamination occurring out in the system. Why? Because the effects of these actions reduce the air dryer’s capacity. In this article, I address some ideas that can make your system more reliable.
Centrifugal compressors are dynamic, and each has a characteristic curve of rising pressure as capacity decreases. Without any control system, the compressor would operate along this natural curve. A centrifugal compressor's flow and pressure are typically controlled by a combination of an inlet control device and an unloading valve (UV).
We are in the midst of the fourth industrial revolution, or, as it is known in Germany, Industry 4.0. In broad terms, the concept describes manufacturing facilities where all of the machines — including the air compressors, along with their corresponding sensors and air treatment equipment — communicate with each other autonomously, recording performance metrics to a local controller, a wireless network, and an external database. These communicative abilities are enabled by the Industrial Internet of Things (IIoT), in which intelligent, networked devices link everything back to a main data hub.
The introduction of rotary screw air compressors controlled by variable speed drives (VSDs) is one of the best energy efficiency innovations introduced to the industry in the past few years. This style of compressor control can significantly reduce the energy wasted by compressors running in the unloaded condition. But the type of VSD control offered by various manufacturers can differ, and some of these differences can affect the efficiency of the system. This article discusses some little known tweaks to VSD compressor control, including some using hidden features that can sometimes be implemented to enhance the savings gained by the installation of this type of compressors.
In recent years, we have seen an upward trend of higher production manufacturers wanting to integrate their air gauging quality checks from a stand-alone, outside-of-machine device where the operator is performing a manual check to an automated in-process gauge. There are several reasons for this trend, including higher quality standards, tighter tolerances, as well as running a leaner operation. The benefits are 100 percent inspection of the required geometric callout, as well as handshaking between measuring device and machine to make each piece better than the prior one. It also removes any bad parts.
In this article, Chad Larrabee from Ingersoll Rand writes about today’s status quo in most air compressor rooms – a group of air compressors all running off their individual controllers with different control schemes attempting to coordinate them. Larrabee then describes the advantages of a smart system controller, which can direct " compressors to respond to one common signal … dynamically matching compressed air supply with demand.” He concludes by outlining the benefits of remote connectivity and automated alerts for maintenance staff.
A major Midwestern aluminum plant was experiencing dwindling compressed air capacity, primarily due to air leaks. If those capacity issues went unresolved, the facility would have needed rental compressors to keep up with demand. Instead, they turned to flow metering to identify and fix the leaks. In this article, they share their solutions with others who may be having similar difficulties.
Compressed Air Best Practices® Magazine recently caught up with Rick Stasyshan, the Compressed Air and Gas Institute’s (CAGI) Technical Consultant, and John Kassin of Cameron to discuss variable inlet guide vanes (IGV). The following interview describes how centrifugal compressor efficiency can be improved thanks to recent developments in IGV technology.
A replacement strategy for air compressors and blowers integrated into a system-level approach towards energy efficiency can deliver significant energy savings and optimize equipment performance. At the Victor Valley Wastewater Reclamation Authority, a blower replacement project yielded annual energy savings of more than 928,000 kWh and $98,000 in energy costs, while improving the reliability of its secondary treatment process. In addition, the agency qualified for important incentives from its electric utility — significantly improving the project economics and resulting in a 2.94-year payback.