Most-Open-Valve (MOV) can be a cost-effective way to optimize aeration energy. It can also be a confusing and troublesome addition to a process automation project. In my experience MOV is the least understood aspect of aeration control. This article will shed light on MOV, the process and energy impacts and why it’s worth the trouble.
An envelope manufacturer is upgrading their vacuum system to include a new VSD controlled pump. As part of the preparation for the installation, an energy baseline was developed, and leakage survey conducted. The auditor used a newly developed acoustic imaging camera as well as a basic ultrasonic leak detector gun. This article describes what was found and some of the challenges faced in detecting leaks in a busy plant.
Meat packaging plants have long used vacuum pumps as a way to remove air and reduce the amount of oxygen in their products’ plastic packaging. Vacuum packaging extends the meat’s shelf life while protecting its flavor and exposure to outside elements, such as freezer burn and bacteria.
At Scholle IPN, Valley Packline’s engineering experience and JetAir’s drying expertise came together to deliver an automated, energy efficient solution. Ultimately, the new system eliminated 120 man-hours each week dedicated entirely to erecting and washing. The new system can be manned by just one employee as it pulls bins directly off delivery trucks, re-erects, washes, and dries them, and feeds them into the facility for refilling. Throughput at Scholle was improved by the system, while energy costs were kept to a minimum.
This article reviews two common pneumatic conveying system types and the importance for each operating plant to know their design and operating parameters particularly conveying air flow velocity and particle velocity profile.
The integrated process that leads to perfectly finished components begins in the plant’s new material store. “One way we’re staying at the leading edge in our market is by researching the latest innovations and choosing the best machine for each process,” Legere explains. “Our new material store, operational in June 2017, is one example. It combines a physical data base of sheet goods with a robotic arm that handles materials and presents them to a cutting machine for processing. After a few minutes, a finished part emerges. All of this occurs with zero human interaction.”
The capacity and pressure requirements of blowers in a Water Resource Recovery Facility (WRRF) are determined by the aeration system. When systems are manually controlled blowers often operate at constant flow and pressure day in, day out. When the aeration system is automatically controlled to maintain a set dissolved oxygen (DO), however, the blower’s flow and system pressure vary constantly. Understanding these variations will help designers and suppliers optimize blower performance.
In open end pipe line suspension flow, or dilute phase pneumatic conveying, proper particle velocity is critical to continuing productivity and product quality. Until recently, measurement of actual particle velocity within the pipe has not been practical outside the laboratory. The plant operating personnel depend on a much less accurate metric - estimating the conveying air velocity in the pipe and relating that to particle velocity.
If you want to understand vacuum systems, you have to get out of the ruts, and slog through the mud and bounce over the rocks a bit. If you’re a “compressed air person”, think outside the box for a few pages with me. I am going to borrow some terms from the “pump people” to explain how vacuum systems are similar, yet different from compressed air systems. There are several ruts to get out of. Remembering what changes and what doesn’t, what is controlled, and how to design systems for optimal energy consumption.
Industrial process operating loads and optimal set points are not usually accurately known at the time of design, so often there is significant mismatch between equipment and the process it serves. To overcome this uncertainty, designers typically oversize equipment. Over time, process changes and equipment efficiencies decline, so equipment might be operating less efficiently than at start-up. Or, equipment can be undersized, thereby hampering the entire system and causing other inefficiencies to compensate. For instance, too much steam usage in the dryer section of a paper machine can occur because of inadequate vacuum at the wet end.
The wastewater treatment plant in the Town of Hurlock, Maryland provides service to approximately 2,100 residences. However, the majority of the water treated comes from a nearby poultry processing plant, giving the plant influent a high organic content. That is why the Town of Hurlock replaced its two million-gallon-per-day (MGD) lagoon plant with a 1.65 MGD four-stage activated sludge facility ten years ago. After construction was completed, operating costs of the new plant were significantly higher than before. This meant the town had to get creative in order to keep costs down for their ratepayers.