Keeping Cooling Towers and Heat Exchangers Clean By Randy Simmons

Filtration Systems Can Reduce Maintenance and Downtime.

To strike an interesting analogy, your cooling tower and heat exchanger is what the lungs and heart are to the human body; when either aren't working properly, it effects other parts of the body and your health suffers. Similarly, when your cooling tower and heat exchanger isn't clean, the heat exchange process doesn't work efficiently and the health of your production and process cooling system suffers.

Process cooling systems that rely on cooling towers to dissipate heat from process cooling water accomplish this by drawing massive volumes of air into the cooling tower as the water travels through the fill material on its way back to the basin. Through the natural evaporative process, heat is dissipated from the water before it reaches the water basin from which it is re-circulated through the chiller then through the heat exchanger and back again (kind of like when you sweat while working and letting the air evaporate the perspiration to cool you down). It is important to realize that cooling towers are gigantic air scrubbers that capture all airborne debris that happen to be floating nearby, and if your system doesn't have effective filtration, the debris can clog the fill and get circulated and trapped in the heat exchanger where it can build-up, restrict water flow and cause your process equipment to malfunction due to overheating.

An example of this is illustrated by a major automotive assembly facility that had faced periodic downtime due to their robotic welding systems not holding tolerances and causing quality problems. After the robotic technicians spent several days trying to initially solve the problem, one of the maintenance workers opened the heat exchanger and discovered that it was impacted with cottonwood seed, insects and other debris - flow had been reduced and the robotic equipment was running hot. Now you might be asking yourself, whey didn't they have some sort of filtration equipment? The answer is simple; at the time the facility was built, the ambient conditions in that area didn't require a filtration system. However, as the years went by and the area became more developed and cottonwood tree populations grew, the need eventually surfaced.

The interesting thing to note about this situation is that even though cleaning the heat exchanger got the robotic welding system back on-line and running at peak performance, it didn't solve the problem. In fact, cleaning heat exchangers is like taking a cold capsule to relieve the symptoms of a cold. Unless you treat the root cause of the problem, the cooling system will suffer time and again. The root cause in this case and in most heat exchanger fouling situations is the cooling tower - stop the debris from getting into the cooling tower and it will protect the entire process cooling system including fill, cooling water, chiller and heat exchanger. With the proper filtration technology, your process cooling system will stay clean and running efficiently all season long.

Selecting The Right Filtration System

It is important to realize that optimizing the ecology and operational efficiency of your evaporative cooling system is best accomplished by combining a chemical treatment regimen with some type of filtration. The reason is that chemical treatment specifically targets suspended solids and particulates of 40 microns and below, while filtration systems are designed to stop larger debris, especially the kind that causes system clogging and fouling.

For cooling tower filtration, there are two general technologies: Water Based Systems for which there are a few different variations and Air Intake Filtration Systems. With water-based systems, the choices include basic water strainers that remove debris by simply passing water through a mesh strainer; sand filtration systems that remove debris by passing the water through sand and centrifugal separators that spin the water and remove the debris through centrifugal action. In contrast, Air Intake Filter Systems remove the debris by filtering the air as it is being drawn into the cooling tower, keeping the debris out of the system in the first place. When considering your filtration options, the following questions should be asked.

• What is the cost associated with downtime due to heat exchanger or cooling tower fouling or clogging? (Knowing this will help you justify your filtration system cost)
• What type of debris is most problematic (can you see it or is it microscopic)?
• Specifically what part of the system does the filter protect?
• Which system provides the greatest filtration surface area (this can directly impact frequency of cleaning - the smaller the filter the more frequently it needs cleaning)
• Can the system be installed without shutting down the cooling tower? (If the cooling tower must be shut down for installation, you need to factor lost productivity into the cost of your filtration system if it's not being installed during shutdown periods.)
• What is the cost associated with both the filter and installation?
• How easy is the system to install and maintain?

Answering the above questions will help you to fully understand your options and to make the best choice for your operation.

In the case of the automotive manufacturer, the solution they selected was the Air Intake Filter system. The reason was that they needed a system that would protect their entire process cooling system including fill material, cooling water, chiller and heat exchanger. When they evaluated water-based systems, they discovered that the options provided varying degrees of protection for the chiller and heat exchanger but didn't protect the cooling tower where the root of their problem was. If they had selected a water-based system, their cooling tower would have still drawn airborne debris into both the fill and water where the water filter would have captured the debris before it circulated throughout the system. From a maintenance standpoint, that would have solved the heat exchanger problem but it would have done little to reduce maintenance on the cooling tower. Further, when they compared the cost of water based filtration versus air intake filtration technologies, Air Intake Filtration was found to be the more cost effective approach for their operation.

If you are not currently using a filtration system as part of your process cooling system, then any filtration technology will give you more protection than you have now, however, selecting a solution best suited to your operation requires that you know what kind of debris is the problem and where it is getting into the system. As a rule of thumb, " don't select a small debris solution to solve a large debris problem". Conversely, "don't select a large debris solution to solve a small debris problem". There is clearly a place for both water based filtration and air intake filtration - be sure you're selecting the right filtration for your specific need.

If you are looking to protect only your chiller and heat exchanger from airborne debris, then one of the water-based filtration technologies in combination with a good water treatment program can help you manage the debris that gets into the cooling water. If on the other hand, you're looking for full process cooling system protection, then you should look at Air Intake Filtration - It will stop the debris from getting into your system in the first place.

Air Solution Company developed and patented the first Air Intake Filter specifically engineered to mount to the outside of cooling towers and other HVAC equipment for purposes of stopping the debris before it entered into the system. Since that time, Air Solution Company has been manufacturing and has introduced a variety of other innovative filter systems including its new Fine Mesh Filter which is engineered for use on small and medium size refrigeration coils and machine fan intake housing units. Air Solution Company Randy Simmons is with Air Solution Company, author of articles can be reached at http://www.airsolutioncompany.com

Article Source: http://EzineArticles.com/?expert=Randy_Simmons

What is a Heat Exchanger? By Martin Applebaum

A heat exchanger is a device that is used to transfer heat from one fluid to another fluid and at the same time preventing the two fluids from coming in contact with one another. There are three main types of heat exchanger. They are as follows:

• air-cooled
• shell and tube
• plate heat exchangers

Dividing the two fluids is usually a metal wall, which acts as a conductor. On one side of the wall is a hot solution, which, while flowing transfers its heat to the cooler solution that is flowing on the other side of the wall.

If the surface area of the heat exchanger is larger then it will create a faster heat transfer. Thermal energy will only flow from a hotter area to a cooler area in order to reach a point of equilibrium.

A heat exchanger can be known by other names as well. For example, in a car, the radiator that acts as an exchanger. The radiator cools the hot fluid by using the airflow over the surface of the radiator.

Other examples of some uses for these devices are swimming pool heating, air conditioners, refrigerators and hot water radiators.

Whether a heat exchanger is used in an industrial or a commercial setting, they are considered very important energy saving devices.

A heat exchanger is usually constructed of cast iron, aluminum, and steel, titanium, bronze or copper. Manufacturers find that one of the biggest problems with these devices is corrosion. This is due to the constant flowing of liquid in these devices.

Manufacturers are always looking for ways to prevent this from happening. The manufacturers are using tubing that is resistant to basic corrosion. They have been creating heat exchangers that feature fins to provide better thermal conductivity. They have found that this has been helping prevent some corrosion.

You will find a heat exchanger in many different types of industry. This would include pulp and paper, pharmaceutical, steel industries, marine, automotive and water treatment plants.

Your guide to everything you have ever wanted to know about a heat exchanger. We also provide information on various types and brands of heat exchangers. Visit our site today! http://www.theheatexchangers.com

By M. Applebaum

Article Source: http://EzineArticles.com/?expert=Martin_Applebaum

Industrial Refrigeration Equipment - Chiller Installation and Equipment By Christine OKelly

Chiller installation and equipment are vital components in many different businesses and industries. They are responsible for keeping buildings and rooms cooled, keeping equipment cool, and are even integrated directly into certain processes or procedures. In this article, we'll look at exactly what this industrial refrigeration equipment does, what kinds you have to choose from, and what they are used for.

What Is It?

Chiller installation involves the process of installing various pumps, condensers, piping, and other components to create a cooling system. This industrial refrigeration equipment uses either water vapor or absorption to pull the heat out of a liquid such as lithium bromide solution, glycol, inhibitors, water, or some other fluid. To cool this liquid, these systems use air, water, or evaporation.

Chiller Installation -- Types Of Systems

Absorption chiller installation involves machines with six main parts -- a solution pump, generator, heat exchanger, condenser, evaporator, and an absorber. Liquid is pumped to the heat exchanger where it is heated. From there, it flows past tubes filled with hot water or steam where it is heated to the boiling point, releasing steam into the condenser above. The lithium bromide from the solution goes back to the heat exchanger. The steam is cooled in the condenser, and the moisture collects at the bottom. At this point, the lithium bromide goes to the evaporator and the absorber where it heads back to the solution pump to complete the cooling cycle.

With vapor-compression industrial refrigeration equipment, the liquid is put under pressure and boiled in a boiler until it becomes dry, saturated vapor. Then, goes through a turbine where it cools and loses its pressure. From there, it is sent to a condenser where it becomes a saturated and cooled. These systems use five types of compressors powered by gas, electric, or steam turbines -- centrifugal, reciprocating, screw-driven, or scroll compressors.

Industrial Chiller Refrigeration Systems

These come in two main styles. A closed loop system pumps a fluid mixed with condition additives, which are held at a specific pressure and temperature, between the system and the tool in a continuous cycle. Along the way, the fluid travels through pumps, valves, and a condenser. Open loop industrial refrigeration equipment pumps the liquid from a large tank through the system and back to the tank in order to keep things cool. These systems often use water, but they can also use air to cool.

Industrial refrigeration equipment comes in many different styles and uses, but regardless of how they compare technically, they are still vital to the operation of many commercial and industrial businesses. This means you want to be certain chiller installation is done properly and that these systems are in top working order at all times. Knowing the basics will help you find a provider that can help you do just that.

Christine O'Kelly is the author for the industrial refrigeration equipment service provider, Andrews Martin Mechanical. For everything from chiller installation to process piping, they offer same day and 24-hour service calls with experienced and friendly professionals.

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Crack Down on Heat Exchanger Fouling By Mike Watson

Heat exchangers are the unsung heroes of many industrial processes and as such they tend to be taken for granted - nobody likes paying for what is often seen to be unnecessary maintenance. Heat exchangers provide duty for so long, that when they start to drop in efficiency, it's usually a gradual process that goes largely unnoticed - until their performance has deteriorated sufficiently to be a problem. Then it really is a problem - and one requiring urgent attention.

What aggravates the situation is the heat exchanger that has never been cleaned properly, coupled with the commercial need to keep it on-line. When the decision is made to carry out cleaning, often nobody knows what the performance of the exchanger is meant to be, either because the drawings have been lost, or no record of any improvement was made after the original cleaning.

When the exchanger finally is opened up to ascertain the extent of the fouling, it's not surprising to find it is so severe that cleaning takes a lot longer than planned. Any benefit that might have been gained by a quick traditional clean is offset by the extended cleaning duration and costs - and, of course, lost production.

If that sounds like a nightmare scenario, bear in mind that this is the sort of situation specialist cleaning companies encounter every week. Cleaning is often carried out without any firm knowledge of how much of an improvement the cleaning will give and how long its effects will last. Having to make 'finger in the wind' predictions clearly is not a satisfactory way to plan maintenance.

One of the most popular and widely-employed heat exchanger configurations in industry, is the straight or hairpin shell-and-tube exchanger. With hundreds or thousands of small-bore tubes bundled together, the extent of quite modest scaling can involve major work to return the exchanger to anything near its commissioned performance. If the outside of the bundle is heavily scaled as well, the cleaning challenge rises by an order of magnitude.

There is potential to bring about a significant improvement in heat exchanger accessibility and 'cleanability', by working more closely with the people who design heat exchangers and fabricate industrial plants.

Better design would lead to improved cleaning - where improved means faster, cleaner and safer, possibly in-situ or even on-line and with better waste containment. It would then be easier and quicker to clean exchangers back to bare metal to return them to duty and their design performance faster.

Plants are generally specified and ordered on the basis of throughput, not accessibility and ease-of-cleaning. Suppliers are happy to comply with this and therefore tend to design heat exchangers with 30-40% excess capacity to ensure that they can continue to provide duty, even when quite extensively fouled. Heat exchangers the world over are currently designed and installed with a view to using one of three systems for cleaning: chemical, pressure jetting and/or mechanical and this approach has remained unchanged for over 50 years.

When it comes to maintenance, refineries - like most of industry - tend to compete on the same basis - a 21-day shutdown is decreed because it's been done that way for maybe the last 20 years. The same cleaning methods are generally used slavishly, with high-pressure water as the cleaning medium.

Most companies look at their heat exchangers in isolation and simply try to extend their run-time, instead of having them designed or re-designed so they can be cleaned more regularly, but faster and better. BP's Coryton refinery, for instance, managed to reduce cleaning time on one shell-and-tube heat exchanger from three days to three hours by applying a different approach to cleaning it.

If a plant is optimized for cleaning, almost full production can be maintained throughout the cleaning process. Relatively minor mechanical changes, such as adding isolating valves to heat exchangers, means that each exchanger, or bank of exchangers, can be taken down and cleaned while the others remain on-line. A redesign of the exchanger so that a header can be removed, means it can then be cleaned with a different system to the standard high-pressure water jetting, in a few hours instead of several days.

At Dow Corning's silicone plant in Barry, south Wales, a tubular boiler and fire tube in the Energy Recovery Unit (ERU) required the removal of a 5mm layer of deposit in as short a time as possible to minimize lost production. Another obstacle was that the unit, which carries waste gases, takes 48 hours to cool and prepare - even with the introduction of a chilled nitrogen purge - before personnel can enter to clean it manually.

The solution involved developing a bespoke remote de-scaler, which was inserted through a small 50cm man-way. Once inside, the de-scaler expanded to fit the hot fire tube, while reaching the full length of the carbon steel tube. With cooling time and man entry eliminated, the shutdown was reduced from five days to three and there was a noticeable improvement in performance of the ERU when it came back on line.

Improved cleaning cycles also mean the rate of future fouling build-up is reduced, which in turn reduces the risk of tubes corroding as a result of the exchanger being open to the atmosphere longer for cleaning.

Heat exchange surfaces therefore remain smoother and provide better heat transfer. If and when the exchanger does foul up, it's easier to clean next time around, using whichever system is preferred. This would represent a change of practice to what has been the norm since the 1980s, for instance, when what was then Mobil in the UK was one of the first refineries to decide that it would extend run-times by abandoning the annual clean and only clean every two years.

Today, typical service intervals have become stretched to three and even four years in some cases, but the apparent operational savings are actually a false economy. Shareholders are indeed happy, because they are getting longer run times, while competing refineries have little choice but to play the same game or lose millions during more frequent shutdowns. Four years down the line, however, the plant will have to come down for major cleaning and maintenance and it will experience a far higher capital replacement cost than ever before.

Mike Watson, Managing and Technical Director

Run by its founder and inventive visionary Mike Watson the company is supported by a wealth of hand selected department managers. With many years experience in developing engineered solutions to complex problems in industry, Mike’s belief is that convention should always be challenged in order to find a better way to achieve improved results. This “never say never” approach, led to him founding Tube Tech in the 1980s. Today, the company cleans the toughest cleaning projects the world can throw at it. Mike often says “If people say it can’t be done, its like a red rag to a bull to me. I will always find a solution”. Mike continues to invest in new technology development, leading the world in new cleaning methodology.

Article Source: http://EzineArticles.com/?expert=Mike_Watson

What is a Ground Source Heat Pump? By Martin Applebaum

What is a ground source heat pump? Many people are using heat pumps these days to heat and cool their homes. However, there are still a lot of people that do not know what these devices actually do. What we hope to do is educate people on the functionality of these machines.

A ground source heat pump uses ground water or the earth or both as its source of heat in the winter. The earth or ground water is the destination for heat removed from the home in the summer. Heat is taken from the earth through a liquid. This liquid is either ground water or antifreeze like solution. The pump then upgrades the liquid and transfers it to indoor air. It is quite a unique process. This is the process for the winter.

During the summer, the process works in reverse fashion. Heat is removed from the home and transferred to the earth through the ground water or antifreeze solution. A different type of ground source heat pump uses refrigerant instead of an antifreeze solution. This type of pump is referred to as the direct expansion earth energy system.

Some ground source heat pumps are designed differently from others. For example, a self-contained unit combines the compressor, heat exchanger, blower and the condenser coil in one single cabinet. A split unit allows the coil to be added to a forced-air furnace and it uses an existing furnace and blower as well.

When searching for the right ground source heat pump for your home, consult the energy efficiency ratings of the units you are looking at. Pumps are available with a wide variety of efficiency ratings.

Typically, it is not a good idea to use a ground source heat pump to provide all the heat you require. It is recommended that you size the unit to meet around sixty to seventy percent of your total demand for heat during the winter. If there is a need for extra heat due to a severe weather condition then a supplementary heating system can meet those occasional demands.

Most heating and cooling stores will carry different styles of the ground source heat pump. Online you will find many reviews on these devices. Reviews range from people who are very happy with their unit to people who are extremely disappointed with their particular heat pump. It pays to do your research before making a purchase of this magnitude.

We provide information for the consumer on heat pump prices along with information on different types of pumps such as a ground source heat pump as well as many other brands of heat pumps. Visit our site today for more information. http://www.heatpumpsrus.com
By M. Applebaum

Article Source: http://EzineArticles.com/?expert=Martin_Applebaum

What Makes a High Efficient Furnace So Efficient? By Mike Meincke

With today's rising energy demands, volatile financial & housing markets and a constant potential of increased living costs looming over our shoulders, catching a financial break anywhere we can as a consumer should be of keen interest to everybody. 90%+ Annual Fuel Utilization Efficiency (AFUE) furnaces may easily provide the solution and can easily off set a household bill or two with all of the energy being saved by this furnace in contrast to the conventional 60-80% AFUE furnace that is more than likely currently in your home even as you read this article. 90%+ AFUE furnaces have a 2 heat exchanger design to avoid wasting heat, in the past the product was problematic when it was first developed in the 90's, but has since been improved to near perfection today by most manufacturers to be a very reliable product and if sized properly and installed properly will save an incredible amount of money on the utility bill that you can capitalize on year in and year out.

The two heat exchanger design is the key feature that allows a 90%+ AFUE furnace to operate so efficiently. A primary heat exchanger handles the ignition of the furnace and the natural gas fire (propane, kerosene, heating oil or what ever the furnace burns) of the furnace burners. As the burners are engaged inside of the heat exchanger, the heat exchanger gets hot so that when the furnace blower turns on, forced air travels over the hot heat exchanger to allow for heat transfer to occur, sending warm air through your air ducts and to ultimately heat the air in your home. With a conventional 60-80% AFUE furnace that is all that is present for a heat exchanger, but through brilliant engineering furnace manufacturers realized that flue gases always creates hot moisture that is typically wasted out of the flue pipe and so they decided to capture this free energy by designing a better product. So engineers went to work to produce the two heat exchanger furnace and incorporated a secondary heat exchanger that looks like a coil to capture the hot flue gas moisture to re use this heat in a more efficient appliance, rather than wasting this heat out of the flue pipe.

Remarkably after 70 years of relatively little change in the heating market in terms of how a furnace basically operated, a vastly more efficient appliance emerged on the market. Two stage technology emerged as well, where engineers realized that a furnace did not necessarily have to high fire gas at all times to effectively heat your home, due to varying weather outside of your home. The two stage gas valve emerged to where a low fire predominately occurs on temperate (less cold) winter days saving an additional 25-35% on gas consumption and then when the weather gets real cold outside the furnace can engage a high fire to ensure that the appliance can keep up with heating your home only when high fire is truly needed, to ensure that the homeowner gets the best of both worlds; saving money and staying comfortable.

A conventional furnace is missing these features, because the conventional furnace can only fire in one stage and just wastes flue gas moisture out of the flue pipe. The venting of a 90%+ AFUE furnace is typically done with PVC piping material and most often is vented to the exterior side of a home. The 90%+ AFUE furnace burns and exhausts vastly more cleaner gases than a conventional furnace effectively lowering emissions as well, so you can feel good about doing your part in the environment when you have a 90%+ AFUE furnace installed in your home.

Some contractors are afraid to install a 90%+ AFUE furnace in your home due to lack of training and an inability to successfully repair furnaces in the first place. One legitimate complaint and or criticism that was true in the past, that these contractors would make, is that parts were more expensive on a 90%+ AFUE furnace and why on earth would you want an expensive repair bill they would ask. That all came to an end when Rheem manufacturing designed their new line of 95% AFUE 2 stage furnaces. All parts selected to make the Rheem 95% AFUE 2 stage furnace work are of quality durable design, but cost effective to repair after the furnace warranty expires.

This would not be the case with the expensive Carrier induced draft motors and chip boards or the expensive chip boards used by Trane and American Standard or all parts by Lennox being of higher expense in their product lines of 90%+ AFUE furnaces. Furthermore, Rheem realized that the primary heat exchanger was the most expensive part of the furnace, so they decided to make a primary heat exchanger tougher than any other manufacturers primary heat exchanger.

The Rheem primary heat exchanger is constructed of stainless steel and is of a tubular design with virtually no seam points present on the part, kind of like a car tail pipe, which rarely breaks. Eliminating seam points on the heat exchanger increases the life span of the part. On the contrary, the Lennox, Carrier, Trane and American Standard heat exchangers are a cheaper clam shell design that is no where near as strong as the tubular designed heat exchanger. The clam shell designed heat exchanger is designed to last a certain amount of years, but once enough time goes by these heat exchangers typically fail due to 4 sides of crimped seams separating the heat exchanger, leading to part failure.

Not only is the Rheem 90%+ AFUE line of furnaces tougher and built with cost effective parts in mind, but they even went as far as ensuring that all Rheem furnaces operate at a vastly lower decibal range making the Rheem furnace the quietest class of furnaces in the residential market today. Carrier, Trane, American Standard and Lennox furnaces will work and if sized and installed properly will last for many years, however when they break, you will surly pay a pretty penny to get them fixed.

When you call out an HVAC company or contractor to perform an in home estimate to install your 90%+ AFUE furnace, make sure that they are evaluating your whole house. Proper furnace sizing will involve an estimator to evaluate wall insulation type, attic insulation type, home exposure, window type, slab type, outdoor landscape, fire places present, duct sizing, how many people occupies the space as well as a few other factors too.

Be leery of the estimator that is in and out of your home in 30 minutes or less, because getting it right during the estimate phase will have a huge effect on achieving maximum efficiency of the furnace and your over all indoor comfort for many years to come. Most of the estimates that reputable heating and air conditioning companies perform may require between 1-2 hours to gather all necessary data, answer customer questions and to write an up front price to do the work.

There are many like minded good companies and contractors out there that conduct themselves that way as well. Your best bet would be to just call out an ACCA member company to perform the estimate, because an ACCA member company will operate professionally, follow higher HVAC standards and receives accredited support in training, up to date trade information and will be up to date with new techniques and standards in the HVAC field. Visit www.acca.org and use the contractor zip code locator to find an ACCA member company near you.

Article By: Mike Meincke. Managing Member of Lucky Duct, LLC. http://www.luckyduct.net.

Mike Meincke is the Managing Member of Lucky Duct, LLC. Lucky Duct, LLC is a full service heating and air conditioning company that operates in the Denver metro market. Lucky Duct, LLC also provides commercial and residential air duct cleaning services using the most powerful equipment in the industry. Mike Meincke is personally licensed for HVAC as a licensed HVAC Supervisor, is EPA certified for refrigeration, has attended numerous manufacturing training courses with Rheem, Goodman and American Standard and has a decade of hands on experience in the HVAC field.

Article Source: http://EzineArticles.com/?expert=Mike_Meincke