Choosing between a refrigerated or desiccant air dryer is dependent on the acceptable moisture content or pressure dew point (PDP) requirement for your application.
Refrigerated air dryers are typically adequate for general purpose compressed air applications and will typically offer anywhere from a 35-40° F pressure dew point (PDP). Cost is typically much less than that of other drying technologies. Refrigerated dryers use a refrigeration compressor and heat exchanger to cool the compressed air and remove moisture. There are two types of refrigerated dryers. The first type is cycling, which is the more energy efficient option and typically used for higher flows and where the flow rate varies from shift to shift. The Cycling or VSD refrigerated dryer, cycles on and off to deliver the correct PDP at the varying flow rate. The other and less expensive option is a non-cycling type. Non-cycling dryers are on all the time and run at the same load as long as they are switched on. The difference between the two, is like running your home refrigerator. You only open it when needed, and thus it “cycles” on and off as needed. Leave the door open all the time, and now you have a “non-cycling” refrigerator. Both types of dryers should have a coalescing pre-filter to remove large quantities of water droplets and oil mist before going into the air dyer. This helps the air dryer to be more efficient in removing moisture from the compressed air. After the dryer, “after-filters” can clean up the remaining oil-mist, particles and hydrocarbons. The type of final filter(s) is dependent upon your air systems’ ISO Air Quality Standard.
Desiccant compressed air dryers are typically used when your application requires very dry compressed air or when the compressed air supply will run outside in cold environments. Desiccant dryers can achieve dew points as low as -100. In some facilities, a Desiccant Air Dryer may only be needed for certain applications and processes. As an example, an auto body shop generally will need only a refrigerate air dryer for the tools and general air uses, but will benefit from having very clean and dry air for the paint booth. Desiccant Air Dryers twin towers and passes the compressed air through a tower that is filled with desiccant. The desiccant attracts the moisture during the timed cycle and then purges, which releases the moisture to the atmosphere. While one tower is drying, the other is purging and regenerating. This type of dryer does use a portion of the dried compressed air as part of the purge cycle so you need to be sure to supply enough compressed air to supply for both your demand and the purge requirement.
The different types of desiccant dryers can include non-heated, heated purge and blower purge. More energy efficient Desiccant dryers will use heated ambient air to purge the off-line tower. Further energy savings can be achieved by using a PDP monitor connected to the dryer controller which will determine when to switch the towers to start the regeneration cycle of the spent tower. The added cost of a Blower Purge Dryer will be quickly off-set by the compressed air system energy savings in most cases.
Desiccant Air Dryers require a high-quality oil-mist removal pre-filter, and a particle filter to keep dust and very fine particles from the dryer bed from getting down-stream to the air distribution system
Everyone is always looking for ways to effectively cut costs to become more profitable. Air compression can be an expensive commodity if not properly maintained. Leaks and worn-down parts reduce the pressure your compressor can produce. Dilapidated seals and fractured piping can fail unexpectedly, creating blowouts. Unintended downtime costs money in lost production or emergency equipment hire. And then you run the risk of physical damage and personal injury claims will pile on the costs of a faulty air compressor.
Compressed air is one of the most widely used forms of energy throughout many industries, with approximately 70% of manufacturers using a compressed air system.
Compressed air can be one of the most expensive forms of energy for manufacturing plants, often using more energy than other equipment. One horsepower of compressed air requires eight horsepower of electricity. With many air compressors running at efficiencies as low as 10 percent, there’s often plenty of room for improvement. Fortunately, 50% of compressed air systems at small- to medium-sized industrial facilities have opportunities for low-cost energy conservation.
Learn how you can save money and keep your air compression working at a premium by downloading our "10 Ways You Can Optimize Your Air Compression and Save Money".
Small adjustments can reduce your operating pressure and energy costs while improving flow rates and output. Learn the final steps you can take to optimize your compressed air system and save energy costs. Make sure that you also know the first 5 things you can learn to "Save your Compressed Air System Operating Costs"
- Review Piping Infrastructure. Many systems aren't optimized.
A piping system design should optimize transfer of compressed air at the desired flow and pressure to the point of use. Increasing the size of a pipe from two to three inches can reduce pressure drop up to 50 percent. Shortening the distance air has to travel can further reduce pressure drops by about 20-40 percent.
The more flow through a pipe the greater the pressure drop will be. Pressure drop in a pipe increases with the square of the increase in flow, which means if the flow is doubled, the pressure drop will increase four times. Air distribution piping should be large enough in diameter to minimize pressure drop.
How can FSC features and benefits help with this step? If your compressed air piping system was installed years ago when your compressor was much smaller, this might be an indication that the distribution pipes are too small. A quick guide is to look at the air compressor outlet size. If your distribution piping is smaller than your air compressor outlet size, then it may be time to get your FS Curtis Distributor in to evaluate your piping system. If up-grades are needed, FS Curtis offers a modular, aluminum piping system that is easy to install and is a cost effective alternative to copper or steel piping.
- Change Filters Systematically. Not every once in a while.
Inspect and replace filters systematically to ensure the quality of your air and prevent pressure drops. Go beyond the air compressor and compressor room. There are several air-line and point-of-use filters within the facility. Those are just as important to maintain as the air compressor and air compressor room filters.
How can FSC features and benefits help with this step? Your FS Curtis Distributor will provide you with a complete Filter Package located on your compressed air system supply side. Your process and type of equipment used will determine the level of air quality needed. If you are not sure what you need, ask your FS Curtis Distributor who can guide your selection using an industry standard selection chart.
- Recover Heat. Compressing air generates heat - reuse it!
It's simple physics that compressing air gives off heat, and as much as 90 percent of that heat can be recovered for use in your operation. For example, you can produce hot water for washrooms or direct warm air into a workspace, warehouse, loading dock, or entryway. The savings can really add up.
How can FSC features and benefits help with this step? A simple heat recovery step can be making sure the hot air from your compressor room is directed into a nearby work space. If you have a larger rotary screw compressor with and e-COOL® Technology, you may find capturing the exhaust air from your air compressor and ducting into your facility during the heating season. More aggressive heat recovery systems can be used to pre-heat water or process materials if you operate larger compressor systems.
- Emphasize Proper Maintenance. Ignoring maintenance costs more.
As with most industrial machinery, a compressor runs more efficiently when properly maintained. Proper compressor maintenance cuts energy costs around one percent and helps prevent breakdowns that result in downtime and lost production. Protect your reputation and profits with proper maintenance.
How can FSC features and benefits help with this step? Your FS Curtis i-Command® Touch Control will help monitor your compressor for items needing maintenance as well as sending signals showing maintenance alerts. Having your FS Curtis Distributor establish a scheduled service interval based on the number of hours your compressor runs per year will save you money in the long run. Take advantage of your Extended Warranty by using correct parts and lubricants at the correct time. If you skip service and don’t do maintenance, then you can expect that future warranty claims if needed, may be rejected. Just like you car, if you don’t take care of it, it won’t take care of you!
- Identify and Eliminate Inappropriate Uses of Compressed Air.
Inappropriate uses of compressed air include any application that can be done more effectively or more efficiently by a method other than compressed air. For example, high pressure air often is used for cooling or applications where much lower air pressure is required.
How can FSC features and benefits help with this step? Your FS Curtis Distributor can help you with this. If you have a Compressed Air Leak Survey scheduled, the Auditor normally is looking for inappropriate uses of compressed air at the same time. Common mis-uses are: blowing off a work station with an air gun instead of using a hand brush; using an air stream as a personal cooler instead of a fan; Plus many, many more ways…..
On our path to becoming the most trusted and dependable compressed air equipment provider in Norther America, we at FS-Curtis have just taken another major step forward.
FS-Curtis is proud to announce the newest addition of our Nx Rotary Screw Air Compressor Series. The Nx18-37 kW (25-50 hp), is now available in Variable Speed Drive! The NxV 18-37kW variable speed drive compressors are built on the same reliable platform as the fixed speed product introduced earlier this year. There are, however, some notable differences. These compressors are controlled by a variable speed drive to match energy consumption to demand, they utilize a robust direct drive arrangement, and the iCommand Touch controller is now standard on the 18-37 kW Variable Speed Drive units at no additional charge. With the standard iCommand-Touch, a full-color screen displays graphs which capture and track factual, real-time air usage by the hour, day, week and month. Historical data can be retrieved at any time with a touch of the screen. The data trending keeps your finger on the pulse of your entire compressed air system.
Introducing this new addition to the FS-Curtis Rotary Screw lineup continues to show that through the dependability of our people and our quality-focused manufacturing, FS-Curtis will continue to be a trusted name serving even more markets through our ever-growing global presence.
In order to help us grow in our mission, we welcome your feedback to help us improve and exceed your expectation.
The FS-Curtis Sales and Marketing Teams
How One Food Processing Plant Saved $150.000 Annually
According to the Advanced Manufacturing Office in the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), American industries spend $5 billion annually on compressed air. In the case of food plants, costs are not documented, leaving compressed air systems principal candidates for waste and abuse.
Follow these 5 steps to save your food processing plant enough money by the end of the year that you'll be glad you took five minutes to read this article.
- Examine and analyze your compressed air system
Note all the uses of compressed air in the plant and all the air compressors available by enlisting the help of engineers and technicians, and then:
Conduct a self-audit of your compressed air system
There are 10 most important targets to evaluate in a compressed air system audit:
- Estimate actions to repair deficienciesCorrect the problems that are the least expensive to repair. Using a Pareto diagram can be useful to help separate the “critical few” deficiencies from the “trivial many” possibilities that are available. For example, the Pareto diagram is shown in figure 1, where the solution for the problem is listed on the X-axis (Improvement). The Y-axis (Savings) shows the estimated savings (less costs) that would result from repairing the problem. Projects shown in the tallest bars should be choosen for implementation.
Figure 1: Pareto diagram helps to select the most effective actions.
- Implement the best solutionsAfter identifying the best alternatives in step three, it is time to execute. Beware that some processors postpone taking action because of time constrains, but it may be worthy to hire extra help to carry out recommended solutions right away. Every action should be measurable in terms of cost and savings.
- Track resultsAll solutions that were implemented should be reviewed regularly to ensure that the results are as expected, or to find out if something has changed or requires additional attention. Once recommnded changes are made, then the five-step process can be repeated to double check yourself.
If you think your company could benefit from having a compressed air system audit performed, viist this link to find a distributor in your area to inquire about scheduling an audit. You can also call our toll free number to talk with a customer service rep about locating an FS-Curtis distributor in your area: 800-925-5431.
Click icons to download product literature for compressors used in the food processing industry.
Check out this article: Food industry factory saves $154.000 in annual energy costs, to see how one plant was able to save over $150.000 annually in energy costs.