Business growth creates new challenges. This is the case for plant engineers and maintenance managers responsible for the efficient operation of the most common form of dust collection equipment — pulse-jet baghouses — used in foundries across the globe. Many baghouses were designed and built to accommodate a certain amount of air flow that was sufficient for past demands. As foundries have increased production, these flow requirements have amplified and the original design of the baghouses are no longer suitable. Their obsolescence is perpetuated by raised scrutiny on emissions and the focus on the business community’s responsiveness as good corporate neighbors and stewards to a sustainable environment.
In this blog, we will explore pleated filter element (PFE) technology and examine how two foundries successfully upgraded their pulse-jet dust collectors by installing PFEs, resulting in:
The Environmental Protection Agency (EPA) and Occupational Safety & Health Administration (OSHA) regulations have become increasingly more stringent, requiring foundries to upgrade their current operational ventilation systems to comply with regulatory standards. Foundries have evaluated their furnaces, shakeout, pouring and cooling lines, sand handling systems, finishing areas and many other parts of their operations reliant on pulse-jet dust collectors for proper ventilation. Their evaluations have found a multitude of problems, including:
As a result, foundries are looking for ways to upgrade their dust collection. The most economical and preferred option is to modify existing baghouses rather than installing completely new systems, which would require significant capital investment. PFEs provide an effective solution to this challenge.
Pleated filter elements, such as those manufactured by Parker Hannifin, are filters that use either a molded polyurethane or metal top and bottom that are used as direct replacement for standard felted filter bag and cage assemblies in pulse-jet baghouses, as well as in new equipment. Spun-bonded polyester fabric is the most common media used in PFEs because of its tight pore structure and rigid physical properties that allow it to hold a self-supported pleat —providing as much as 200 to 300% more filtration area at 99.992% efficiency than a filter bag in the same tubesheet hole.
A major Midwest foundry used a three-compartment, 882-bag shaker baghouse to ventilate four induction furnaces, a scrap preheater system, and a magnesium inoculation station. The foundry struggled with the following problems in its dust collection system:
As a solution, the company converted the original shaker system to an engineered pulse-jet style cleaning system using BHA® PFEs manufactured by Parker Hannifin's Industrial Gas Filtration and Generation Division. The baghouse was retrofitted with a new tubesheet and a walk-in clean air plenum, to allow for a top-load design filter element. The baghouse has been operating consistently since the retrofit.
Since the retrofit, the baghouse has been operating consistently and the following results have been reported:
A large foundry that manufactures castings for the automotive industry had a top-load design pulse-jet baghouse that contained 650 felted filter bags and cages. The unit ventilated several shot blast cabinets, grinders, and other finishing equipment. The system was originally designed at an air-to-cloth ratio of 6.1:1. The filter bags measured 5.25 in. in diameter by 12 ft. in length, for a total cloth area of 16.5 ft2 per filter bag. The challenges the foundry was experiencing with the current design were:
The foundry engineering team determined that installing Parker BHA PFEs in the dust collector was the most cost-effective solution.
Post installation results include:
Pulse-jet dust collectors used in most foundry applications can be successfully upgraded with the installation of pleated filter elements. The case studies show that when aggressively designed to air-to-cloth ratios and demands for increased airflow capacity cause poor dust collector performance, the installation of PFEs can dramatically lower differential pressures, improve filtering efficiencies, reduce emissions and lower overall plant maintenance requirements.
This blog was contributed by the Filtration technology team, Parker Industrial Gas Filtration and Generation Division.
Gas turbine performance is affected by the environmental challenges of a specific power plant installation. In a recent project located in the Middle East, a filtration solution to protect the turbine needed to be designed to address each of the conditions faced, including varying amounts of:
The spectrum of potential hazards that could be faced at a turbine installation means one filter cannot meet all needs. Even the different forms of dust or moisture present need to be considered within the design of the filter house.
A brutal environment for gas turbines
In the Middle East, a mixture of sandstorms, heat, mist and moisture from random fog events, make for a brutal environment for a gas turbine. It is the combination of the moisture in thick fog combined with high dust concentrations that can be particularly challenging for a gas turbine filter system.
Without the correct design and implementation of a system, the installation is at risk of sudden pressure increases, gas turbine shutdowns, difficult and time-consuming maintenance and greatly shortened filter life. Indeed, as one operator was experiencing, it is not uncommon for pre-filters to require changing every two or three days and final filters to need replacement after just six or seven months, as opposed to a normal life expectancy of over two years. The increased labour and ongoing cost to keep operations running and reduced availability of the gas turbine were having a serious impact on the operation’s bottom line.
The gas turbine installation in question was at a power plant in a coastal, desert location in the Middle East. Seasonal fog events and extremely high levels of dust were causing havoc with the system. After careful review of the installation and specific environmental conditions, however, relatively simple changes led to a dramatic improvement in performance.
When to pulse – and when not to
One of the first areas to be considered was the pulse system settings. A pulse system removes dust build-up on the filter and tends to operate in one of two ways. In the first, it can be set to run continuously without regard for the differential pressure.
Alternatively, however, it can be configured to run when the differential pressure across the filter reaches a certain level. Once this level is seen, the pulse system turns on, cleans the filters and then turns off when a low differential pressure setpoint is met.
The site’s pulse system was set to run continuously. The issue this created, however, was that the fine dust in the area was leaving the filters in a dust cloud and simply becoming re-entrained on the filter. The system was changed to operate only when differential pressure reached a pre-set trigger level. The switching levels were established based on testing with the local environmental conditions and found to be optimized with the system turning on at 1.5” wg (water gauge) and off at 1.0” wg. This meant the filters were cleaned before pressure became an issue but not before a dust cake built up on them that enabled gravity to help the dust move down the filter house. Typical set points for pulse cleaning start around 3.0” wg and stop at 2.5 or 2.0” wg.
Handling the moisture from the fog
The next area to be considered were the coalescers, which were experiencing serious issues. Coalescers are used to remove moisture from the air flow prior to it reaching the filter. If there is a lot of moisture in the air flow when it reaches the filtration stages, small moisture droplets combine with the dust and sand to create blockages and sudden increases in differential pressure. The size of these droplets means they can also work their way into the matrix of the filter media and get stuck. Coalescers usually work to prevent this from happening by combining small moisture droplets to form bigger, heavier ones — many of which will then naturally fall out of the airflow.
The site in question had traditional coalescers installed, known as mat coalescers, which employ media similar to that used in dust filtration. The issue with these, however, was that the high volumes of dust were quickly clogging them and, with no path for the inlet air flow, they were being forced out of place. Once the air was able to completely bypass the coalescers, the moist air and dust were continuing to the filter and creating blockages. Placing the coalescing technology with a modern, fully washable, 100% synthetic mesh resolved this issue and, even after 12 months of operation, the coalescers remain firmly in place and doing the task for which they are installed.
Unlike the traditional mat equivalents, the new synthetic media coalescers had been specifically designed to allow the sand and dust to pass through. The new units work by using a two-stage coalescence configuration. The first stage is a moisture separator with coalescing efficiency down to 50 microns. The second stage, a clearcurrent TS1000 coalescer, has 99 percent coalescing efficiency for droplets down to 10 microns but which has limited dust removal capability. It is this deliberate limitation of dust removal capability which avoids blockages and significantly reduces the maintenance overheads where high levels of both dust and moisture are present. The dry dust is then easily handled by the filtration system, to prevent it from damaging the turbine.
Two simple changes equal huge improvements in performance
Following these two changes on site, pulse system settings and coalescer technology employed, the site has experienced no shutdowns because of problems with the filter system or sudden differential pressure increases. The self-cleaning filter life is exceeding the customer requirement of two years and maintenance intervals have been extended. This has reduced operating costs, limited manual labour interventions required, and increased production availability — significantly improving operating profits.
In regions where extreme conditions as found, such as in the Middle East, operators are advised to:
Success is not about paper specifications
Measurement of the success of a filtration solution cannot be measured by specification comparisons or laboratory testing, as these do not portray the real-world conditions of each installation. Instead, success criteria need to be based on critical factors such as the reduction in turbine downtime and outages for filter replacements.
The example given above shows that, with the correct experience and expertise, significant improvements to turbine performance can be gained with even relatively small solutions and adjustments. System design and settings need to be geared towards the real-world environment in which the solution is installed. Working with filtration experts, other turbine operators can benefit from evaluating total solution management of their inlet systems.
View the presentation given at Middle East Rotating Machinery Technology and Innovation Conference & Showcase (ROTIC) 2018
About Parker Gas Turbine Filtration
With more than 50 years of experience delivering innovative solutions for gas turbine inlet filtration and monitoring fleet-wide performance data, our industry and applications experts will select the appropriate filter for your site designed to meet your specific operating goals.
Parker Gas Turbine Filtration supplies a full range of inlet systems and filters engineered to meet your operating goals, including:
Through our Parker brands, altair® and clearcurrent®, we are the choice for advanced filtration for new units and replacement filters. Our inlet system designs include self-cleaning (pulse) and static inlet systems for all gas turbine OEMs. We supply a full range of filter types at all efficiency levels. The predictable and reliable performance of our air filters significantly reduces compressor contamination and the need for unplanned maintenance for gas turbines in power plant applications.
This article contributed by David Trisante and Dan Burch.
David Trisante is sales director at Parker Hannifin Gas Turbine Filtration division. Trisante earned his engineering degree in the prestigious Universitat Politecnica de Catalunya (Spain) and the Aalborg Univeritet i Esbjerg (Denmark). He holds more than 20 years’ experience in purification and air pollution control markets as well as in a variety of filtration equipment ranging from dust collectors, electrostatic precipitators or gas turbine air intake systems.
Dan Burch is pricing manager, Gas Turbine Filtration (GTF) Division, Parker Hannifin. He’s covered all aspects of the company’s filtration offerings, with a particular focus on developing marketing and pricing strategies for gas turbine inlet filtration products. He has 15 years of experience in marketing and journalism roles. Dan has a B.A. in journalism from Indiana University and an MBA in marketing from the University of Missouri-Kansas City (UMKC).
The case study and paper were presented as part of the Middle East Rotary Machinery Technology 2018 conference.Related content
The consequences of failure during downstream processing are severe. Following the Affinity Chromotography stage, the value of the product increases significantly at every step. A failure at the final bulk filling stage, therefore, could lead to the waste of millions of dollars’ worth of drug product.
It’s vital, therefore, to safeguard the bulk filling process. But traditional methods of conducting bulk fill operations have several disadvantages including:
1. Manual handling
This introduces the possibility of human error to the bulk filling process. It is also labour intensive, meaning that process operators need to divert their resources into this task.
2. Operator training
When bulk filling is carried out manually, investment must be made in operator training. This can be costly, both financially and in terms of the time dedicated to it by personnel.
3. Supply chain complexity
By using a range of components from several different suppliers in the bulk filling process, there is more potential for variation – and more time must be spent on sourcing and ordering suitable components.
4. Laminar air flow (LAF) maintenance and validation
In traditional bulk fill operations, laminar air flow must be maintained and validated to protect the products from contamination. This requires time and resources.
5. Shipping issues
At the shipping stage, poor handling of bottles – and the use of unsuitable containers – can lead to damage to products before they even arrive at their destination.
6. Non-standard operations and process variability
Traditional methods of bulk filling introduce variability into the process. If bulk filling operations aren’t standardized, they can be subject to a number of factors which can impact the final product. Factors such as different flow rates applied by different operators come into play.
Automating and enclosing bulk fill operations can address the challenges detailed above and increase safety for operators. Parker Bioscience Filtration has developed the SciLog® SciPure FD system as an automated and integrated single-use system for final bulk filtration, filter integrity testing and dispensing into final bulk product containers.
Here are some of the benefits:
This reduces the risk of human error from manual handling and allows operators’ resources to be spent on other tasks.
Standardizing operations means that training can be simplified and variations in the process can be eliminated.
Enclosing the process allows operators to process highly potent molecules and protects both the operators and the process. And, as the flow path is completely enclosed, both filtration and dispensing can be performed in areas of lower classification, eliminating the requirement for vertical laminar flow cabinets.
The SciLog® SciPure FD system
The SciLog® SciPure FD system benefits from innovative component selection based around material science studies, improved filling accuracy (+/-1%), and greater flexibility in the scale of filling (from 50ml samples to 20L).
The system features include a barcode reader for manifold tracking, reverse flow and purge options to maximize product recovery and fully programmable alarms and interlocks to product and process.
A validated shipping solution
To reduce the risk of damage to the product when shipping, Parker Bioscience Filtration has designed a fully validated shipping solution to complement and extend the capabilities of the SciLog® SciPure FD System. Parker Bioscience Filtration has created a unique bottle design that offers manufacturers the confidence that bulk drug products will arrive at their final destinations without contamination.
Parker Bioscience Filtration drew on its extensive material science knowledge during the development of the bottle and material selection was based on an FMEA study. The bottle integrity has been validated down to -89˚C.
Parker Bioscience has also developed an anti-foaming device that eliminates foam and enables a higher filling speed.
The development of the SciLog® SciPure FD System is an example of the change in the vendor/end user relationship: by using a vendor such as Parker Bioscience Filtration, which can provide a complete solution, end users can increase their productivity and gain greater control and protection over their processes.
This post was contributed by Graeme Proctor, product manager (single-use technologies), Parker Bioscience Filtration, United Kingdom
Parker Bioscience Filtration specializes in automating and controlling single-use bioprocesses. By integrating sensory and automation technology into a process, a manufacturer can control the fluid more effectively, ensuring the quality of the final product. Visit www.parker.com/bioscience to find out more.
Mycoplasma contamination events, although rare, can have an enormous and immediate negative impact on biomanufacturers leading to reduced productivity and delays in products reaching patients.
Parker Bioscience Filtration will be examining how to implement a holistic approach to the prevention of Mycoplasma contamination in an upcoming webinar entitled: The Prevention and Control of Mycoplasma Contamination in Bioprocessing which will take place on January 15, 2019, at 3 p.m. London time/10 a.m. New York time.
Here presenters Guy Matthews, global market development manager, and Dr. Carolyn Heslop, technical support group team leader, answer common questions on the threat posed by Mycoplasma contamination and how this can be tackled by biopharmaceutical manufacturers.
What are the potential consequences of Mycoplasma contamination?
“Short-term consequences for a biopharmaceutical manufacturer can include unplanned downtime and lost batches. This can result in the supply of pharmaceutical products to patients being affected. In the long term, there may be financial consequences through a loss of confidence in the manufacturer and a resulting decline in the company’s stock value.”
— Guy Matthews
Why does Mycoplasma contamination pose such a risk in biopharmaceutical manufacturing processes?
“As Mycoplasma can infect mammalian cell cultures through adhesion and subsequent fusion to cell membranes, this allows them to exploit the conditions and synthesized molecules provided by the host cell. This means that detection and quarantine procedures must also be implemented around cell lines. Mycoplasma can vary in size and shape from 0.2 microns upwards, have no peptidoglycan cell wall and exhibit pleomorphism (the ability to alter size and shape in relation to environmental conditions). This means that they are capable of penetrating sterilizing grade filtration systems.”
— Dr. Carolyn Heslop
What steps should biopharmaceutical manufacturers consider in combatting this threat?
“Start with the basics: employing the standards of Good Laboratory Practice. Considering factors such as the storage and packaging of media, and understanding the nature of the supply chain are all important factors in mitigating the risk of Mycoplasma contamination. Identifying where contamination is likely to originate from and mitigating the risk at the source can prevent problems further on in the process. Gamma irradiation or heat inactivation to eliminate Mycoplasma present on gamma or heat-stable incoming raw materials can be used to guard against contamination. However, not all media components can be heated or subjected to irradiation. Therefore, filtration has a vital role to play in combating contamination during the biopharmaceutical process. Biopharmaceutical manufacturers should consult with their filter suppliers on issues such as filter sizing to ensure that their filtration systems are optimized appropriately."
— Guy Matthews
What kind of filtration system is needed?
“In order to effectively control Mycoplasma, the use of a Mycoplasma retentive 0.1 micron filter – such as Parker's PROPOR MR – is recommended. However, as the filter is twice as tight as a standard 0.2 micron sterilizing grade filter, pressure levels in the process can be a major concern. Filters may not function effectively if the flow is too rapid – for instance when pressure peaks occur.”
— Dr Carolyn Heslop
Is there a solution to this challenge?
“Biopharmaceutical manufacturers could consider implementing an automated single-use system. This ensures that critical process parameters such as pressure levels can be constantly monitored, ensuring the process stays within the validated process limits. An automated single-use system will also remove the possibility of human error – and give manufacturers more control over the process.”
— Guy Matthews
Sign up for our webinar and learn how to mitigate the risk of Mycoplasma contamination
For more information on the advantages of single-use technology in mitigating the risk of Mycoplasma contamination and how to implement a holistic approach to the prevention of Mycoplasma contamination, register for Parker Bioscience Filtration’s forthcoming webinar: The Prevention and Control of Mycoplasma Contamination in Bioprocessing. The webinar will take place on January 15, 2019, at 3 p.m. London time/10 a.m. New York time.
This post was contributed by Guy Matthews, global market development manager, and Dr Carolyn Heslop, technical support group team leader, at Parker Bioscience Filtration, United Kingdom.
Parker Bioscience Filtration specializes in automating and controlling single-use processes. By integrating sensory and automation technology into a process, a biopharmaceutical manufacturer can control the fluid more effectively, ensuring the quality of the final product.
Many companies, including those in the food and beverage, pharmaceutical, cosmetics, manufacturing and electronics industries, recognize the negative effects on quality created by oil contact with their product during production. Product rejections and consumer safety concerns associated with oil contamination can have broad negative financial and commercial impacts on a company. However, an often overlooked source of oil in compressed air — ambient air — is frequently misunderstood, underestimated or ignored.
In this blog, we’ll examine the effect that ambient oil vapour levels can have on downstream compressed air quality and what to consider when looking for technically oil-free compressed air to ISO8573-1 Class 0 or Class 1 for total oil.
What is ambient air?
Ambient air is the air we breathe and it’s all around us. It’s also the air that is drawn in by air compressors. Ambient air is made up of approximately 78% nitrogen and 21% oxygen. The remaining 1% contains a mix of argon, carbon, helium and hydrogen as well as a variety of contaminants — oil vapour being one of them. Ambient air is an often overlooked source of contamination that can have a big impact on a compressed air system.
How is ambient air contaminated?
Ambient air quality is directly impacted by air pollution caused by industrial processes such as burning fossil fuels and emissions from vehicle exhaust, oil and gas fields, paints, and solvents.
Oil vapour in ambient air is made up of a combination of hydrocarbons and volatile organic compounds (VOC). Ambient air typically contains between 0.05mg/m3 and 0.5mg/m3 of oil vapor, however, levels can be higher in dense, urban or industrial environments or next to car parks and busy roadways.
These levels may seem negligible, but when it comes to compressed air contamination, we must consider the effect that compressing the air has on the ambient contamination, the amount flowing into the compressed air system, and the time the compressor is operating.
Compressing air – compounding the problem?
The process of compression, as well as flow rate and time, build the level of oil in the compressed air that travels through a production system — air that eventually finds its way to production equipment, instrumentation, products and packaging materials.
Compression, or pressurizing the compressed air, can significantly increase the volume of oil. The greater the operating pressure, the higher the potential level of oil in the compressed air. This is compounded by the flow rate and time of operation. Compressors are often designed to operate continuously. This means that the concentration of oil continues to multiply in the confined space of the compressed air system. In turn, it will only exit the system at points where the air is released. These exit points are often in areas where the contaminated air comes in contact with product, production equipment or instrumentation. So, what may seem like negligible levels of hydrocarbons and VOC in ambient air, can become a great concern when the same is drawn in and compressed for use in manufacturing.
Effect on quality
Once inside the compressed air system, oil vapour will cool and condense, mixing with water in the air. This contamination causes numerous problems to the compressed air storage and distribution system, production equipment and final product leading to:
Due to the financial and commercial impact of contaminated product, many companies specify the use of an oil-free compressor, in the mistaken belief that this will deliver oil-free compressed air to critical applications.
Oil-free compressed air systems are typically installed without downstream purification equipment intended to remove oil, as they are deemed unnecessary accompaniments. While it is true that oil-free compressed air systems will not contribute contamination in the manner that oil lubricated systems will, oil vapour from ambient air remains untreated.Considerations for technically oil-free air
Technically oil-free air, in accordance with ISO8573-1 (international standard for compressed air purity) Class 0 or Class 1 for Total Oil, can only be guaranteed through the proper application of downstream purification equipment. This equipment may include water separators and coalescing filters to remove liquid water and oil, aerosols of water and oil, and solid particulate as well as adsorption filters to treat oil vapour. Compressed air users seeking an oil-free source of air would be wise to consider these precautionary purification steps, whether they are used with oil-lubricated or oil-free compressed air systems.
In order to establish compliance with ISO8573-1 Class 0 or Class 1, the international standards categorizing oil level in compressed air, users must perform tests to assess both oil aerosol and oil vapor presence in their systems. The levels of each phase will combine to establish total oil in the compressed air system.
To conduct the tests, samples of each phase must be drawn through a solvent extraction process and analyzed using gas chromatography (GC) or Fourier transform infrared (FT-IR) technology. The combination of the two methods will provide an accurate reading down to 0.003mg/m3.
While there are other methods for testing oil levels, like Photo Ionisation Detector (PID), these will leave certain compounds undetected. To this end, they should be used for estimation purposes only. GC and FT-IR will provide results that can be related to ISO standards with reliable and complete accuracy.
Parker has recently introduced a new compressed air purification system. The OFAS Oil Free Air System is a fully integrated heatless compressed air dryer and filtration package suitable for use with any compressor type and can be installed in the compressor room or at the point of use. Fitted with a third adsorbent column for oil vapour removal, the OFAS has been third-party validated by Lloyds register to provide ISO 8573-1 Class 0, with respect to total oil from both oil-lubricated and oil free compressors, ensuring the highest quality air at the point of use for critical applications.
Compressed air is vital to any production process. Whether it comes into direct contact with the product or is used to automate a process, a clean, dry reliable compressed air supply is essential. If the compressed air contains oil, the consequences can be high both financially and in terms of brand damage.
This blog was contributed by Mark White, compressed air treatment applications manager, Parker Gas Separation and Filtration Division, EMEA.
One of the challenges faced in any biopharmaceutical process is bioburden control and containment — or how do you keep what is out, "out" and what is in, ‘"n".
For a stainless steel-based manufacturing system, the process is well understood. The lines are set up, the CIP and SIP cycles are run, the appropriate valves are closed and the system is pressurized and then left for a period of time, perhaps overnight, while it is monitored for pressure decay. If the pressure decay is minimal, you have an integral system.
If you tried this method with a single-use system, assuming the bag could take the pressure, at a minimum you would see losses from the tubing as it is a porous material which has a diffusion rate. Identifying a fail in a single-use system based on pressure decay, therefore, becomes difficult. The question is, is the decay due to a leak and therefore a faulty assembly or is it diffusion across the tubing material on an assembly that is intact and fit for use? Commercially available systems are now available which will provide the answers.
Integrity testers or leak detection systems?
A key point for discussion is: should the biopharma industry be talking about integrity testers or should we be talking about leak detection systems? This is an important difference due to the weight this industry places on the word integrity, especially if we talk about integrity tests.
If we use the language of integrity testing, it implies a level of security backed up by validation and a clear binary result. The meaning in this context is well defined and if a system fails an integrity test, a batch ultimately could be rejected, pending any rework or investigation.
At the post integrity testing stage, you can report that a sterilizing grade filter is integral or is not by using recognized and validated methods. However, it may be more difficult to make the same statement for a single-use assembly.
As an industry, we should be sure what integrity means in this context and how it should be described.
Leak detection on a system requires and allows for the interpretation of the results. Of course, if the interpretation is backed up by the manufacturer’s validation package then so much the better. The questions that are open are:
There is no need, however, to revert to stainless steel in bioprocessing operations. Stainless steel is not without its own challenges and potential points of weakness. The connections on a system, many of which are not used in a process — for example blanking ports on a vessel — all need to be assembled and tested. The stresses and strains, when going from ambient temperature to 121oC and back again, which are put on stainless steel systems, are avoided in single-use.
But we should be very clear about what we are testing and what those test results mean, so as not to create a false sense of security. The impact of simply assuming a single-use assembly is integral when there is no knowledge of how testing has been carried out can have serious consequences for a biopharmaceutical manufacturer.
We should also be challenging the vendors of single-use systems to ensure that the facilities and processes used to build and ship assemblies minimize any risk and that those processes are validated.
The old adage "you cannot test in quality, you must build it in", certainly rings true in this case.
Modified atmosphere packaging is now a prerequisite for many food products, extending shelf life, appearance and taste by preventing or retarding spoilage mechanisms. Quite simply, modified atmosphere packaging uses the main constituent gases that make up the Earth’s atmosphere – nitrogen, oxygen and carbon dioxide then alters the mix and or ratios to obtain beneficial qualities enabling extended food preservation.
Food grade nitrogen within Europe is given an additive number, E941, as it is classed as a food additive when used for modified atmosphere packaging applications. Many other legislative authorities globally also adopt the European standard or have a very similar specification.
*99% including other inert gases such as noble gases (mainly argon)Impurities:
The main contaminant to consider within the specification is oxygen @ ≤1%, however, this is for the nitrogen gas itself whether produced from on-site generation or supplied via traditional methods such as high-pressure cylinders or bulk liquid. One important factor for gas generation is that the higher the acceptable level of maximum remaining oxygen content, (MROC), in the output N2 stream, the less compressed air is required to produce the gas and hence the lower the overall unit gas cost. Typically, to produce nitrogen from a gas generator at 10 ppm MROC is 3 times higher cost than at 0.5%.
Often the oxygen content within the finished gas flushed food pack is higher than 1% and the actual acceptable level is specified based on the type of food, designated shelf life, storage conditions and possible spoilage mechanisms.
Many food producers employ the services of expert independent food research establishments such as Campden BRI based in the UK for example. In these facilities, packing and storage conditions along with microbial assessment can be evaluated pertaining to the specific food product to establish the optimum modified atmosphere specification — including maximum remaining oxygen content within the finished pack.
A specific range of foods that have a long history of benefiting from modified atmosphere packaging are dried, powdered products such as coffee, infant formula and spices. These are routinely packaged using Vertical Form Fill and Seal, (VFFS), machinery, fitted with a dedicated nitrogen gas flushing system.
Parker has many nitrogen gas generators operating globally, employed for modified atmosphere packaging of dried powdered foods with VFFS machines. Establishing initial suitability can often be challenging if simple logic is not taken into consideration.
On-site nitrogen generation: a safe, low-cost alternative to traditional methods
Food producers that use MAP are rapidly realising the benefits of on-site generation as a safe, convenient, sustainable and low-cost alternative to traditional methods of supply. The change from purchased gas to self-produced might seem a little daunting to some and there is often insistence that the new generated supply must match the existing specification with regards to oxygen content.
MROC in purchased gas vs. a nitrogen generator
Sometimes an impasse is reached where a food producer wants to change to a Parker gas generator but insists on 99.999% (10ppm maximum remaining oxygen content) purity unless it can be proven that a slightly higher oxygen content gas will achieve exactly the same results, even though the acceptable oxygen level within the finished pack would typically be in the region of 2%.
Parker appreciates this stance and fully understands that for food producers there is a lot at stake in getting it right. However, considering using purchased gas at typically 10-20 ppm purity, does switching to generated gas at say 0.5% change the 2% MROC achievable in the finished pack?
In reality, it doesn’t and the reason for this is that it is almost impossible to flush all of the air out of the packs as they are rapidly and continuously formed within the packing machine, so some oxygen content from the residual ambient air always remains. Secondly, as the product is dropped into the pack from the multi-head weigher through the filling funnel, it pulls in ambient air, thus introducing a little more oxygen into the pack.
One possible way of confirming the suitability of an on-site supply of food grade nitrogen at various purities to establish the most suitable would be to install a small nitrogen generator system to run on a trial basis. This however in most instances is not logistically or physically viable.
Recently Parker UK was faced with the dilemma where a high-quality coffee producer desperately wanted to convert from an expensive and problematic long-standing bulk liquid supply to a NITROSource PSA on-site solution. The producer fully understood the huge cost savings that could be enjoyed by specifying 0.5% purity as opposed to 10ppm but wanted absolute proof that their reputation and produce would not be jeopardised by the change in purity.
To overcome the problems associated with the installation of a full-scale trial unit, Parker's nitrogen generation manufacturing GSFE Division UK and the Local UK Parker sales company devised a solution to introduce a small, fully variable quantity of food grade compressed air into the existing high purity nitrogen supply, thus enabling the ability to increase the MROC to any desired level. A calibrated independent oxygen analyser was installed at the device outlet to constantly monitor O2 levels.
A series of tests were carried out on one packing line where the device was installed and the producer’s quality assurance department was on hand to oversee the trial and sample the finished packs using a calibrated bench top pack analyser for MROC.
The machine was run at its standard 36 bags/min first with only the 10ppm liquid supply and then 2 levels of raised oxygen gas at 0.1% and 0.5% achieved through a small bleed in of food grade compressed air.
As can be seen from the table of results, there was virtually zero difference between the gas purities with regards to MROC in the pack and the target O2 level was maintained well below the limit.
The test was evaluated by the producer's decision-making team and a twin bank NITROSource PSA system was duly ordered and installed to fulfill the demand of the entire factory.
Interesting to note that on the day of change over from the existing liquid supply to Parker generated gas, the operatives and QA department were not informed so as to execute a blind test. We are happy to report that the system actually ran for 3 weeks without any detected difference before the parties concerned were eventually informed!
Considering the total cost of ownership including energy, maintenance and capital expenditure, the entire system is expected to realise pay-back within 2 years and reduce cost by up to 75% thereafter.
Now, watch this video to learn more about NITROSource:
For additional information on Parker NITROSource gas generators, download the product brochure. You can also contact Phil Green, the author, directly: email@example.com
This post was contributed by Phil Green, industrial gas application and training manager, Parker Gas Separation and Filtration Division EMEA.
There are numerous manufacturers in the water cooler market. Water coolers are also called chillers but it is important to draw a clear distinction between process water coolers and chillers for industrial or non-industrial cooling applications.
Many people think that all chillers for the industrial manufacturing sector are the same but there is a risk of making a huge error of judgment which could have an impact on the final choice for the application.
When referring to cooling and climate control systems, we mean systems that can control both the temperature and the humidity level of a space. They are usually used for cooling rooms, electrical cabinets or other places where the water cooling temperature does not have to be precise and constant.
Chillers for cooling process water, on the other hand, are compression water cooling units that can be sub-divided, depending on the fluid used for the cooling of the condenser, into air-cooled and water-cooled. The most common cooling power range for installed systems is between 2 and 750 kW.
Process coolers for industry provide a high and constant degree of precision of the output water temperature (in all atmospheric conditions) and keep the fluid clean to prevent damage to the end user. In fact, process chillers are used to cool industrial machinery that requires the cooling fluid to be uncontaminated and at a precise and constant temperature. For example, in all of the hydraulic circuits of machines, if the oil temperature exceeds a certain limit, the machine shuts down with a resulting loss of productivity. Therefore, precise and constant cooling is both necessary and crucial for speeding up and improving production processes. When there is a need for accuracy and a water temperature lower than the ambient temperature, precision process coolers offer the only solution. A precision cooling chiller is a machine designed to cool water using a cooling circuit. It is a closed circuit which must ensure:
Parker's Hyperchill Plus industrial water chiller is compact, easy to use, safe and reliable in all operating conditions — guaranteeing precise and accurate control of the water temperature. Cooling capacities range from 1.7kW to 23.6kW. The availability of a wide range of accessories and options makes Hyperchill Plus an extremely flexible solution which can satisfy demands in all industrial applications. Thanks to the non-ferrous hydraulic circuit, Hyperchill Plus ensures stable operating conditions, maintaining the highest possible quality and cleanliness, which has an ensuing positive impact on the efficiency and productivity of the process, reducing maintenance costs and system downtime. Each individual Hyperchill Plus is extensively tested in the factory to guarantee the highest possible levels of efficiency and reliability in all operating conditions.
Applications requiring cooling capacities from 28kW to 360kW
Parker's Hyperchill range of water chillers is designed specifically for industrial applications. Advanced solutions, the utmost attention to detail and a highly sophisticated production process have resulted in a compact, reliable and easy-to-use product that offers flexibility in a variety of conditions as well as precise control of the water temperature. The high level of efficiency and low operating costs make Hyperchill the perfect solution for the modern industry.
Parker is the leading supplier of water coolers for production processes which offer complete ease of use and a high degree of operational reliability thanks to the use of the latest technologies and the availability of a vast array of versions and accessories. The Parker liquid coolers range represents a simple but effective solution to most common problems arising from the use of water. The chart below contains general technical specifications.
To learn more about Hyperchill Plus download the brochure.
For information on Parker's complete compressed air and gas treatment solutions including the Hyperchill range of water chillers, download the brochure.
This article was contributed by Fabio Bruno, compressed air purification, gas generation & process cooling application engineer, Parker Gas Separation and Filtration Division EMEA.
In an industrial manufacturing plant, coalescing filters are probably the most important piece of purification equipment found in a compressed air system. They treat six of the ten main contaminants found in compressed air (atmospheric particulate, rust, pipe scale, micro-organisms and aerosols of oil and water). But more importantly, they are also used to protect refrigeration and adsorption (desiccant) air dryers from contamination.
This blog compares the benefits of installing a pair of coalescing filters in series versus a 2 in 1 filter in terms of differential pressure, dirt holding capacity, and total cost of ownership.Coalescing filters are usually installed in pairs but why is this so?
Typically, coalescing compressed air filters are installed close to where the compressor is located (either in the compressor room on larger installation or on the compressor itself for smaller fixed or portable compressors).
In order to effectively reduce the aerosols of oil and water, micro-organisms and particles to a level that will protect the compressed air dryer requires the use of a fine filter (treating contaminants down to 0.01 micron).
The particulate found in a compressed air system is of varying sizes and as this filter is very fine, it will block rapidly with large particles (especially rust and pipe scale).
As the filter blocks, the differential pressure across the filter increases. This not only reduces the available pressure downstream, it also requires the compressor to generate the compressed air at a higher pressure, resulting in higher operating costs.
On average, it is found that for every 1 bar additional generation pressure there is a loss of 7% in specific energy, therefore keeping pressure losses low helps reduce operating costs.
Running a compressed air filter with high differential pressure is therefore very costly and keeping pressure losses as low as possible is imperative. One way to keep the pressure losses low is to change the filter element on a frequent basis (every 3-6 months). Another way is to oversize the filter; however, making a filter too large has its own issues in terms of filtration performance, purchase cost and installation. Neither way is a cost-effective compressed air treatment solution.
If the fine filter could be protected, the pressure losses could be reduced, therefore the most cost-effective solution is to install a pair of coalescing filters in series.
Each filter will reduce the same 6 contaminants but to differing levels of purity. The first filter, a general purpose filter protects the second, a high-efficiency filter from bulk contamination. This not only improves filtration performance but more importantly, reduces pressure losses and operational costs. Additionally, it also extends the service life of the element from 3-6 months to 12 months.
Are there alternatives to the 2 filter installation?
Yes, there are single filter alternatives, but care has to be taken with this type of filter as they do not always provide the perceived benefits.2 in 1 filters
In an attempt to reduce the pressure losses associated with compressed air filters, a number of manufacturers are now offering 2 in 1 filters. These are claimed to reduce the pressure losses associated with having two filter housings (and therefore energy consumption) whilst providing the same level of purification (i.e. particulate retention & oil carryover down to 0.01 micron / 0.01 mg/m3 or lower). In theory, the thought process is a sound one, however, these types of filter do not always deliver in practice.Understanding differential pressure (dP)
In a compressed air filter, pressure losses are a combination of fixed pressure loss and incremental pressure loss. Fixed pressure losses are designed into the filter from the beginning and come from the filter housing and element endcap designs whereas incremental pressure losses come from the filter element as it starts operating. Pressure losses for compressed air purification equipment are stated as dP or differential Pressure.
Literature dP is often used to select one filter brand over another, however many users are unaware that this data is only indicative of a filter in a clean, “as new” condition and does not indicate how a filter blocks as it operates.
When selecting a filter, its blockage characteristics must also be considered as this is an indication as to the filters dirt holding capacity (and true operational cost).
Therefore, to show the real performance of the 2 in 1 type of filter and the true benefits of their new OIL-X filter range, a comparative test between a pair of Parker domnick hunter OIL-X coalescing filters (Grades AO + AA) and a single 2 in 1 filter was undertaken.
As the filters on test are coalescing filters, they were wetted out with oil aerosol (in accordance with ISO12500-1, the international standard for coalescing filter testing) to give an initial saturated dP representative of a new filter as it enters the first days of service. Oil carryover performance was also recorded.
Results of the initial ISO12500-1 testing showed that whilst the OIL-X AO + AA combination achieved the claimed literature performance for oil carryover and initial wet dP, the 2 in 1 filter oil carryover performance was 87% higher than literature claims and initial saturated dP 5% higher.
The second test determines the dirt loading characteristics of the two offerings by injecting and diffusing equal amounts of test particulate into the air stream and measuring the dP (this is done 12 times to simulate monthly particulate loading).
So whilst the initial performance of the two filters may look similar in literature, actual dirt load testing indicates otherwise as can be seen in the graph. Testing confirms that a pair of Parker domnick hunter OIL-X filters have a much higher dirt holding capacity than the 2 in 1 filter and will, therefore, have significantly lower operational costs.
From the test data, true operational costs can now be calculated and the table below shows the financial savings available by installing a pair of Parker OIL-X filters over a 2 in 1 filter.
Based upon 37kW compressor / Cost of electricity £0.10. Parker OIL-X savings will be greater with larger filter/compressor combinations.Total cost of ownership
The table highlights operational costs, however, when selecting compressed air purification equipment, the total cost of ownership (TCO) should always be considered (purchase price / operational costs/maintenance costs). The initial purchase price for the two Parker OIL-X filters is only 26% higher than the 2 in 1 filter whilst a pair of Parker OIL-X filter elements is 42% lower than a single element for the 2 in 1. As the 2 in 1 filter has a lower operating lifetime than OIL-X, it may require 2 element changes per year in which case the pair of OIL-X elements is 183% lower cost than a pair of 2 in 1 elements. What seems like a low-cost alternative may turn out to be a costly investment.Parker domnick hunter OIL-X filter range
The new OIL-X filter range is the latest addition to Parker's comprehensive line of compressed air and gas treatment product solutions. The new OIL-X technology has been designed to carefully balance the need for precise compressed air quality with the need for low dP, low energy consumption and low lifetime cost.
Parker domnick hunter OIL-X filters incorporate unique flow management devices to significantly reduce the pressure losses associated with poor housing designs whilst their filter elements use airflow management technology, specially selected filtration media, energy efficient coatings and unique deep pleated element construction. This not only ensures air quality, it also provides a high dirt holding capacity, culminating in a filter element dP that starts low and remains low for the 12-month lifetime of the filter element.
All Parker domnick hunter OIL-X filtration grades have performance 3rd party validated by Lloyds register in accordance with international standards and are backed up by an air quality guarantee.
For more information on Parker's compressed air treatment solutions, download the brochure.
This blog was contributed by Mark White, compressed air treatment applications manager, Parker Gas Separation and Filtration Division, EMEA.
During normal operation, a Parker nitrogen generator should not vent any significant volumes of oxygen or nitrogen gas within the installation location as long as the area is adequately sized and ventilated. This obviously depends on quite a few factors including but not limited to - the free volume of room where the system is installed or gas used within, potential exhaust/permeate flow, possible nitrogen vent capacity, and room ambient air volume change rate.
Ensure adequate ventilation and set vessel vent flow to ensure no oxygen depletion occurs. Alternatively, fit a suitable flexible hose of the correct pressure rating to the vessel drain connection and vent to a safe location.Labelling and warning notices