Industrial Utility Efficiency    

System Assessment

One of the most satisfying parts of being a compressed air system auditor is resolving compressed air system reliability issues. This article exposes a seldom, if ever, mentioned problem that can occur when air dryers are dedicated to air compressors. It examines a real-world application and discusses the action taken to remedy the situation.

Compressor Controls

It was early summer, the air compressors were above the production floor on a mezzanine, and temperatures were heating up both outdoors and indoors. The compressed air system was comprised of three 500-horsepower centrifugal air compressors, and one 350-horsepower variable speed drive oil-free rotary screw air compressor.

Piping Storage

An air receiver tank (sometimes called an air compressor tank or compressed air storage tank) is a type of pressure vessel that receives air from the air compressor and holds it under pressure for future use. The tanks come in a range of sizes and in both vertical and horizontal configurations. An air receiver tank provides temporary storage for compressed air. It also helps your compressed air system run more efficiently.

End Uses

For Imerys S.A. there’s little question about the importance of managing dust collection systems it uses to control and reduce harmful particulates in its worldwide minerals processing facilities. And now there’s zero doubt about the tremendous energy savings it stands to save by reducing the amount of compressed air needed for these same dust collectors.

Pressure

Most industrial systems like compressed air have essentially random demand if you look at the long-term life cycle of the system. Hundreds, even thousands of independent small and large subsystems require constant or varying flow. These demands are typically not timed or synchronized with each other, so they aggregate to a fairly random flow profile, within a range. That range changes significantly when production processes change. Certainly a 2-week audit might show some patterns that appear predictable for demand A (“production”) and demand B (“non-production”) or day type, but they change over time as the plant adapts to new production systems and removes old ones. If demand was that profile forever, a lesser experienced auditor might be tempted to size one set of compressors that work perfectly for that profile but not for alternates.

Air Treatment/N2

Dew point is simply the temperature to which air must be cooled for the water vapor within to condense into dew or frost. At any temperature, there is a maximum amount of water vapor that the air can hold. This maximum amount is called the water vapor saturation pressure. If more water vapor is added beyond this point, it will result in condensation.

Leaks

Awareness and interest in leak detection only continues to grow thanks to a number of factors. What we have seen over the last 20 years is a more sustainable way of thinking, established international energy efficiency standards, reliable leak detection technology, and best practices to implement leak detection.

Pneumatics

In manufacturing and packaging facilities that rely on pneumatics, there’s a four-letter word worse than virtually any other: leak. Unidentified air leakage and unexpected maintenance in pneumatic systems are significant sources of revenue and productivity loss but identifying the cause of leakages and preventing unforeseen downtime is typically a challenge.

Vacuum Blowers

Every municipality and utility is facing the reality of rising energy costs. In 2010, the Town of Billerica, MA, which is located 22 miles northwest of Boston with a population of just under 40,000 residents, engaged Process Energy Services and Woodard & Curran to conduct an energy evaluation of the Town’s Wastewater Treatment Facility (WWTF) and pump station systems sponsored by National Grid. The objective of the evaluation was to provide an overview of each facility system to determine how electrical energy and natural gas were being used at the facility and to identify and develop potential costsaving projects.
Reverse pulse type dust collectors often represent a challenge to compressed air energy efficiency, and sometimes throw a wrench into the works by causing huge air pressure fluctuations, high transient flows and just plain large leaks. This article discusses this type of dust collector, often installed in food processing plants, and gives some real-life examples of problematic installations. Some suggested measures are mentioned to ensure your dust collectors keep running in a trouble-free manner.
Maintenance is the customer of controls and energy engineering is the customer of monitoring. And I discussed potential problems that can occur when combining monitoring and control in the same system. In this article, I will get more specific about building practical systems that address both controls and monitoring.
Launched in 2006, the TTU-IAC program provides manufacturers in the state with free energy, productivity, and waste assessments – including best practices for compressed air systems, and blowers and vacuum, as well as cooling towers and chillers. The assessments to date have provided manufacturers in the program with $27.48 million in recommended cost savings, equaling 3.82 trillion British thermal units of energy savings.
This article reviews the benefits and design considerations of controlling system pressure from the air compressor room to the production headers and selected production processes and areas. Over the last several decades, the phrase “demand-side control” has become the generic term to describe establishing a “flat line” header pressure using proper storage and an appropriate pressure regulator, or “pressure flow controller.” Use of a demand-side controller to control pressure and flow can be implemented at the entry to the production area header(s) and at selected production areas or processes.
In a strategic approach to improving its management of compressed air, the company initiated an upgrade of its compressed air system at its Midway plant. In so doing, SumiRiko Tennessee saves 2.1 million kWh and $100,000 in energy costs per year at the plant.  Additionally, lower energy use resulted in the reduction in CO2 of 800 tons per year. With a utility rebate, the project paid for itself within two years.
Many OEMs of air compressors, dryers, sensors and master controls are integrating monitoring features and capabilities into their components. It would seem a no-brainer to keep it simple and use those sensors and systems for both control and monitoring. What could be simpler? 
By far the most important development in the world of screw type air compressors has been the introduction of variable speed control using electronic variable frequency drives (VFD’s). Systems that run with at least one air compressor at part load can almost always operate more efficiently if a well-controlled VFD is added to the system. But what if a system has two or more VFD units? This article discusses the challenges in controlling multiple VFD air compressors with some suggested solutions.
Compressed air represents one of the largest opportunities for immediate energy savings, which accounts for an average of 15% of an industrial facility’s electrical consumption. In fact, over a 10-year period, electricity can make up 76% of the total compressed air system costs. Monitoring compressed air usage, identifying compressed air waste and inefficiencies, and making investments in new compressed air equipment – including piping – are tangible ways businesses can cut their operating costs by lowering their electricity bill.
The advent of manifold-mounted, plug-in pneumatic valves has been a boon for machine builders. It allows them to mount complete valve packages in a safe and secure location on a machine. Using a D-sub connector, serial interface module, or similar single-point wiring system, all of the electrical control outputs can feed into one location on the manifold, greatly simplifying the wiring.
Baseline measurements include flow, power, pressure, production output, and other relevant variables impacting compressed air use. These data evaluate trending averages to develop Key Performance Indicator (KPI) and Energy Performance Indicator (EnPI) parameters and establish base‑year performance. The focus of this article is the application, evaluation, and analysis of baseline measurements to provide information necessary to improve Compressed Air Supply Efficiency.