Industrial Utility Efficiency    

Technology

Among the many “systems” plant personnel are concerned with, the compressed air system often provides the biggest opportunity for improvement and overall savings. There are many manufacturers and several air compressor technologies to choose from. Reciprocating or rotary? Fixed speed or variable speed? Oil flooded or oil free? Single-stage or two-stage technology? It’s enough to make anyone want to run and hide!

Air Compressors

Properly sizing a compressed air system can help determine if your facility has enough air to adequately supply your production equipment. Designing a cost effective system that minimizes any interruptions to productivity requires thoughtful planning and design. Typically, the desired outcomes of such a system focus on stable pressure and efficient operation, though it is important to note that each of these elements requires a unique solution. This article will provide guidance in proper selection considerations and suggest when a centrifugal air compressor may be ideal for your needs.

Air Treatment

Air compressors can produce a lot of water. Humidity in ambient air, once compressed, results in much of this water falling out, which we know as condensate. On a warm and humid summer day with inlet air temperatures of 80 oF, a 75-horsepower (hp) air compressor running fully loaded can produce over 25 gallons of condensate in just one eight-hour shift, with another five gallons being produced once the compressed air is sent through a dryer. The compression process allows for the air, water vapor, and lubricating fluids to mix. Once the condensate leaves the system, trace amounts of lubricant travel with it. This condensate should be processed through an oil-water separator before being discharged to groundwater or wastewater treatment plants.

Blowers

The plant upgrades, in combination with a progressive management strategy, allows the plant to consume less energy and reduce its reliance on outside contractors for biosolids removal, resulting in total operational savings of approximately $60,000 per year.  The plant is also positioned to efficiently manage the area’s wastewater for decades to come.

Compressor Controls

Companies will experience periods of increased production, as well as periods of slower or stopped production. It’s the nature of being in business. Understanding the implications of these business shifts for compressed-air installations (the powerhouse behind a facility’s production) is key for ensuring that air compressors remain functional and efficient. Here are guidelines to ensure your facility’s compressed-air system operates at top performance, no matter the speed of production.

Instrumentation

Like any system, to properly manage compressed air equipment some measurements have to be taken. Typically, some sort of data logging equipment is installed to measure various pressures, amps or power, flow, and sometimes temperatures and dewpoints. Placing this equipment on a system is like putting an electrocardiograph machine on a human heart, the heartbeat of the compressed air system in a plant can be analyzed to determine if everything is normal or if there is a problem, all without interrupting the system. 

Pneumatics

In this article, we discuss problems associated with static electricity in industrial manufacturing operations and how to effectively address them. At the atomic level, materials have a balance of positively charged protons in the nucleus and negatively charged electrons in the shell. Balance requires the same number of each.  A static charge occurs when that balance shifts due to the loss or gain of one or more electrons from the atom or molecule. The primary mechanism for this loss or gain, among several possibilities, is friction.

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.
As an end user, have you ever heard the message to put in the biggest VFD air compressor, and the system will always be reliable and efficient.  Why do an audit?  Just add up the compressors on site and put one VFD for that size or larger.  Why have the complexity of multiple compressors, storage, sequencing, etc?  Even better, put in two of them, one for the whole system, and one for back-up.  If you could wave a wand, wouldn’t that be what every system should look like?  Perfect peace and efficiency, with 100% confidence of reliability.
The 2017 Hannover Messe attracted 225,000 visitors with 75,000 coming from outside Germany. The over-arching theme of the event was the Industrial Internet of Things – or Industry 4.0, as it is known in Germany. Dr. Jochen Köckler, Member of the Managing Board at Deutsche Messe commented,“Over the past five days, Hannover has served as a global hub for all things related to Industrie 4.0. Every sector involved in the digitalization of industry was on hand to showcase its answers to the key question faced by industrial enterprises everywhere: How can I best get my company into shape for the digital future?
A complete compressed air system assessment should provide detailed information on both the supply and demand sides of the system. The supply-side refers to the equipment supplying compressed air – the air compressor, dryers, filters, piping and storage tanks.  The purpose of this article is to illustrate what information we believe a factory should receive from a supply-side system assessment and more importantly – what information a plant should always know about their compressed air system.
A newly constructed ethanol plant experienced control gap issues shortly after comissioning.  This article discusses the cause of the issue and how the problem was solved.
This article will talk about testing.  I will assume a “typical” system, a screw air compressor mix with regenerative dryers. Testing has to be done at several stages and locations, due to the cobbled-together nature of a compressed air system.
A pharmaceutical product manufacturer spends an estimated $137,443 annually on electricity to operate the oil-free air compressors in its compressed air system. The compressed air system operates well and is providing the level of purification required.  Our team visited the plant and identified a group of projects which could reduce compressed air demand and reduce energy costs by $42,248 – or 31% of current use.
A large pharmaceutical company needed huge flow rates of 30 psig air to aerate multiple fermentation processes which create food-grade materials.  Flow could vary from about 12,000 scfm to 35,000 scfm.  There were a variety of batch processes, mostly running independently.  An hour-by-hour schedule for anticipated air flow is developed every afternoon for the next day.  Based on that schedule, the boiler operators run the air compressors that can handle the load range for the whole day. In reality, the peak flow can be higher than anticipated.
Compressed Air Best Practices® Magazine interviewed Mr. Warwick Rampley, the National Sales Manager for Sydney (Australia) based, Basil V.R. Greatrex Pty Ltd. It’s not every day one is asked to deliver a system able to provide both a reliable compressed air dew point of -80°C (-112°F) and high purity nitrogen.  We work with some excellent technology suppliers and have engineered a rather interesting system.  Although our firm was founded in 1919, this application is one of the most demanding we’ve encountered. Basil V.R. Greatrex is a unique company as we focus only on compressed air measurement, compressed air quality and compressed air efficiency.
The Lafarge Cement Distribution terminal located in Winnipeg, Canada has significantly reduced the site electrical demand and energy charges by changing the way they transport their cement.  Two new low-pressure rotary screw air compressors have replaced two large high-pressure air compressors that previously powered their dense phase transport system.  The resulting power reduction has saved the company 46 percent in transport operating costs.
A centrifugal air compressor operates over a range of flows and discharge pressures. The operating performance curve is shaped by the selected individual internal components and affected by operating conditions such as inlet pressure, inlet temperature, and cooling water temperature. The process of dynamic compression, as applied in a centrifugal compressor operating stage, is velocity and kinetic energy converted to pressure and temperature as the flow is restricted. Another term for this process is mass flow – the power requirement to deliver the rated cfm of flow at the rated pressure (psig) is determined by the weight of the air.