Industrial Utility Efficiency    

Piping/Storage

Technology is available which enables a compressed air flow meter to measure not only the magnitude of the flow, but also the direction. Why is this important? In this article we will describe two case studies where bi-directional compressed air flow measurement plays a key role to come to the right conclusions. In the first case study, we will describe an electronics manufacturing plant, which has a large interconnected ring network with two air compressor rooms located in different buildings. The two air compressor rooms are about five hundred feet apart. In the second case study, the effect of compressed air flow measurement upstream of a local receiver tank is described.
The Compressed Air Challenge® Fundamentals and Advanced training discuss the benefits of using central controllers to efficiently control system compressors. These systems are called “System Master” controls. Modern day System Master Controls use advanced technologies to network air compressors in a preprogrammed sequence. A properly configured network with the right size and type of trim compressor can typically hold the supply air pressure in a tight band of +/- 2 psi. Because of this capability, many users feel the application of System Master Control negates the benefit of applying Pressure-Flow Control to stabilize the plant air pressure.
In continuation of our series examining the application of storage in a compressed air system, this article will focus on another type of supply side storage concept: demand (dry) storage. Before discussing the definition, application and use of demand storage, I would like to reiterate that contrary to current thought, consideration should be given to control (wet) and demand (dry) storage being separate storage solutions based on their primary purpose
The subject of compressed air piping has probably had more pages written about it than any other topic, even storage. Like many other topics in “practical” compressed air technology, a significant portion of this is controversial and often directly opposed.
There are many ways to use storage in a compressed air system to improve the performance and repeatability of production equipment. No one method is a total solution. Some industry professionals will tell you that storage is not required for certain types of compressors. The system, however, can not afford the impact on either performance or operating costs. The alternative to applying storage is to operate at higher pressures with more power all of the time in order to support critical applications and the peak air demand experienced in the system.
While control storage was originally an integral component of a reciprocating air compressor installation, this article will only briefly explore that application. The content of this article will focus instead on rotary screw installations since the rotary screw air compressor has essentially replaced the reciprocating as the compressor of choice in industrial applications. It should also be noted that in compressed air systems where reciprocating and rotary screw air compressors are operating together, control storage should always be utilized.
This food container plant spends $1,028,672 annually on energy to operate the compressed air system at their facility. This figure will increase as electric rates are projected to be raised from their current average of 6.2 cents per kWh. The set of projects identified in the compressed air system assessment could reduce these energy costs by $616,000 per year (49%). Estimated costs for completing the supply and demand-side projects total $525,000. These costs are offset by having qualified for utility company energy incentives of $425,000. After the incentives, this project delivered a simple ROI of two (2) months.
This article describes a compressed air retrofit project implemented at Kellogg’s Eggo factory located in San Jose, California. Kellogg’s continues to realize both annual energy savings and quality improvements because of the upgrade. In addition, Kellogg’s received a substantial utility incentive from Pacific Gas and Electric Company, which was based on the achieved energy savings.
Power Smart® efficiency measures for compressed air systems at Tolko’s paper mill and sawmill at The Pas are saving the company more than $125,000 a year.  
Production processes get their energy from the air stored at higher pressure in the piping distribution system. The air compressors simply replenish the air that is consumed. It is an important distinction to make. The energy input in compressing the air is supplied to the connecting pipes for delivery to the various demands throughout the facility.
Pneumatic air cylinders play a major role in allowing a modern sawmill to produce at the high-speed production rates required. Stable air pressure is critical to allow the air cylinders to respond in a timely manner and avoid any production delays.