Do you know and track the annual generated nitrogen energy cost per SCFM? Do you know what factors drive this value and what action you can take to control the optimum lower levels? In this article we intend to illustrate the magnitude of potential wasted energy dollars when the compressed air system and the on-site nitrogen generation system are not properly monitored and controlled.
This article dealt with all the various conditions that can and do affect the performance capacity of various types of air compressors in actual flow capacity (SCFM at site conditions).
This is a two-part article looking at factors impacting decisions on whether to use air or water-cooled air compressors. It also provides heat recovery guidelines for both situations. Part 2 will provide a review of alternative cooling water system options and their approximate operating costs.
Over the last two decades, there has been a significant increase of manufacturing facilities deciding to produce their own nitrogen on-site, using compressed air systems and nitrogen generators. They are choosing on-site nitrogen generation, instead of purchasing and receiving deliveries of nitrogen by the cylinder or having a “Nitrogen Over the Fence” supplier.
This is a two-part article looking at factors impacting decisions on whether to use air or water-cooled air compressors. It also provides heat recovery guidelines for both situations. Part 1 will provide a brief history on air compressor cooling, a review of cooling water sources and costs, and some cooling cost comparisons between air and water-cooled air compressors.
This assessment identifies a path to reduce the energy consumption from $85,000 to $51,000 per year. This can be done with little capital by fixing poppet-valve control problems on the air compressors and reducing flow and pressure requirements. Due to article space limitations, this article does not provide detail on the flow reduction projects. It focuses only on the impact these projects have on the air compressors and provides readers with a template on the information they should have on their units, by shift.
The use of high performance boosters to raise low pressure air (100 psig) to high pressure air (500-600 psig) for blow molders is very power efficient and offers good operating performance and reliability when well applied.
Do the questions in the title seem like simple questions? There are many things that confuse the issue including air compressor condition, controls as applied, interconnecting pipe size and configuration and effective storage. All of these have been covered in many technical compressed air papers and articles. The topic many don’t use or understand is how to calculate the actual value of these initial questions at the operating sites and conditions.
The dust is collected on the bag or fingers, and when the cake of dust is of appropriate thickness and structure, a pulse or pulses of compressed air hits or shocks the bag and knocks the cake off. This pulse may sometimes be accompanied by physical shaking and even reverse air flows, depending on design.
In order for a compressed air system to be designed properly, altitude must be taken into consideration. In order to calculate the demand profile, tool air consumption must also be adjusted for altitude.
Just as many ambient air issues with regard to the actual equipment operating environment are created by personnel and can be corrected by personnel, inlet air contamination is always created by humans and there is almost always a correction that will either eliminate the issue or mitigate the effect.
Operating the vacuum system at higher levels (then necessary) affects the needed volumetric flow to compensate for leaks. This required compensation of volume (ACFM) must be added to the nominal production flow demand. The ambient air leak into the system will expand to the highest vacuum level, which is known as the “Expansion Ratio.”
What is vacuum as used in the manufacturing/industrial sector? The clearest answer is – a contained space with gaseous pressures much less than surrounding atmospheric pressure. Atmospheric pressure (ATM) is expressed in many units of measure. At room temperature a cubic foot of contained air at sea level – the random movement and molecular impact on the walls of the containment vessel equal a force of 14.7 psia for every square inch of the walls.
Often when you mention heat of compression the first thought generally relates to HOC desiccant dryers, which are also an under-applied opportunity for heat recovery. However, there are many other heat of compression recoverable energy savings opportunities in all compressed air and gas systems. This article reviews many opportunities in energy heat recovery and provides answer to commonly asked question.
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.
Plant personnel had experienced ongoing problems with its process grinder performance due to unstable compressed air pressure. This created potential problems in terms of product quality. Grinders do not work properly without the proper pressure. Additionally, plant staff wanted to address these concerns, prior to a proposed 30% increase in production, and suggested raising the header pressure from the current operating pressure of 98 psig to 125 psig. The thought behind this was if the pressure from the header to the grinder process was dropping to 63 psig, then raising the pressure to the process would give the grinders enough pressure to work through higher peak production times.
Introduced in the 1960s and operated successfully worldwide, the Heat of Compression (HOC) Desiccant Dryer has been a viable and successful compressed air drying technology for over 50 years. In our ongoing series on missed-demand opportunities, we’ll discuss basic operating parameters of HOC dryers and shed light on common misperceptions associated with the technology.
This major food manufacturing plant in the Midwest uses compressed air and onsite nitrogen generation to operate multiple snack production and packaging lines. The plant spends an estimated $430,344 annually on energy to operate its compressed air system based on an average rate of 4.5 cents per kWh.
On a recent project, at a polyethylene terephthalate (PET) blow-mold and filling operation, a very effective measurement plan resulted in a full synchronization of the supply side air to blow molds with significant reduction in total air use and increases in productivity and quality.
Whenever we start a compressed-air energy survey there are always two key topics plant personnel feel are paramount – leaks and reducing pressure. In this installment of our series on missed demand-side opportunities we’ll address the importance of compressed air system pressure.
Air Operated Double Diaphragm (AODD) Pumps are popular and versatile. Often, they also offer an excellent opportunity to lower the demand for compressed air, especially given the latest advances in controls and the energy savings to be realized.
In this ongoing column, we share insights into technologies that offer the opportunity to affordably and easily lower compressed air use and generate energy savings – all while achieving relatively quick payback. But finding these technologies on the production floor isn’t always easy or straightforward. In fact, there are many times when a technological solution is far less than obvious. Such is the case with cooling of control enclosures, which represent a significant area for high-energy savings with little upfront investment. Here is some out-of-the-box thinking… check that… inside-the-box thinking… for optimizing control of enclosure cooling and coming out ahead.
When the 18th Century Italian physicist Giovanni Venturi discovered when air is forced through a conical nozzle its velocity increases as the pressure decreases, neither he nor anyone could conceive it would ultimately spawn one of the most used and most highly controversial products in the industry today- the Venturi vacuum generator (aka, ejector).
In this series we covered some very common issues in the Compressed Air Generation or “Supply Side” with regard to misapplying some capacity controls and installing different types of air compressors with piping and/ or orientation. These can preclude any reduction in compressed air demand on the production side from effectively translating lower air usage into a commensurate level input energy.
This article is going to identify two air compressor control situations that will preclude translating air use reduction in the production area into lower input energy into the air compressor.
